Merge branch 'main' into mktemp-set-dir-mode

.github/workflows/CICD.yml

@@ -24,7 +24,7 @@ jobs:
     name: Style/cargo-deny
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v2
+    - uses: actions/checkout@v3
     - uses: EmbarkStudios/cargo-deny-action@v1
 
   style_deps:
@@ -43,7 +43,7 @@ jobs:
           - { os: macos-latest   , features: "feat_Tier1,feat_require_unix,feat_require_unix_utmpx" }
           - { os: windows-latest , features: feat_os_windows }
     steps:
-    - uses: actions/checkout@v2
+    - uses: actions/checkout@v3
     - uses: Swatinem/rust-cache@v1
     - name: Initialize workflow variables
       id: vars
@@ -101,7 +101,7 @@ jobs:
         job:
           - { os: ubuntu-latest , features: feat_os_unix }
     steps:
-    - uses: actions/checkout@v2
+    - uses: actions/checkout@v3
     - uses: Swatinem/rust-cache@v1
     - name: Initialize workflow variables
       id: vars
@@ -165,7 +165,7 @@ jobs:
           - { os: macos-latest   , features: feat_os_macos }
           - { os: windows-latest , features: feat_os_windows }
     steps:
-    - uses: actions/checkout@v2
+    - uses: actions/checkout@v3
     - uses: Swatinem/rust-cache@v1
     - name: Initialize workflow variables
       id: vars
@@ -223,7 +223,7 @@ jobs:
         job:
           - { os: ubuntu-latest , features: feat_os_unix }
     steps:
-    - uses: actions/checkout@v2
+    - uses: actions/checkout@v3
     - uses: Swatinem/rust-cache@v1
     - name: Initialize workflow variables
       id: vars
@@ -275,7 +275,7 @@ jobs:
 #          - { os: macos-latest   , features: feat_os_macos }
 #          - { os: windows-latest , features: feat_os_windows }
     steps:
-    - uses: actions/checkout@v2
+    - uses: actions/checkout@v3
     - uses: Swatinem/rust-cache@v1
     - name: Initialize workflow variables
       id: vars
@@ -320,7 +320,7 @@ jobs:
         job:
           - { os: ubuntu-latest , features: feat_os_unix }
     steps:
-    - uses: actions/checkout@v2
+    - uses: actions/checkout@v3
     - uses: Swatinem/rust-cache@v1
     - name: Initialize workflow variables
       id: vars
@@ -397,7 +397,7 @@ jobs:
         job:
           - { os: ubuntu-latest , features: feat_os_unix }
     steps:
-    - uses: actions/checkout@v2
+    - uses: actions/checkout@v3
     - uses: Swatinem/rust-cache@v1
     - name: Install `rust` toolchain
       uses: actions-rs/toolchain@v1
@@ -422,7 +422,7 @@ jobs:
         job:
           - { os: ubuntu-latest , features: feat_os_unix }
     steps:
-    - uses: actions/checkout@v2
+    - uses: actions/checkout@v3
     - uses: Swatinem/rust-cache@v1
     - name: Install `rust` toolchain
       uses: actions-rs/toolchain@v1
@@ -452,7 +452,7 @@ jobs:
           - { os: macos-latest   , features: feat_os_macos }
           - { os: windows-latest , features: feat_os_windows }
     steps:
-    - uses: actions/checkout@v2
+    - uses: actions/checkout@v3
     - uses: Swatinem/rust-cache@v1
     - name: Install `rust` toolchain
       uses: actions-rs/toolchain@v1
@@ -478,7 +478,7 @@ jobs:
           - { os: macos-latest   , features: feat_os_macos }
           - { os: windows-latest , features: feat_os_windows }
     steps:
-    - uses: actions/checkout@v2
+    - uses: actions/checkout@v3
     - uses: Swatinem/rust-cache@v1
     - name: Install `rust` toolchain
       uses: actions-rs/toolchain@v1
@@ -502,7 +502,7 @@ jobs:
         job:
           - { os: ubuntu-latest , features: feat_os_unix }
     steps:
-    - uses: actions/checkout@v2
+    - uses: actions/checkout@v3
     - uses: Swatinem/rust-cache@v1
     - name: Install dependencies
       shell: bash
@@ -534,7 +534,7 @@ jobs:
               --arg size "$SIZE" \
               --arg multisize "$SIZEMULTI" \
               '{($date): { sha: $sha, size: $size, multisize: $multisize, }}' > size-result.json
-    - uses: actions/upload-artifact@v2
+    - uses: actions/upload-artifact@v3
       with:
         name: size-result
         path: size-result.json
@@ -568,7 +568,7 @@ jobs:
           - { os: windows-latest , target: x86_64-pc-windows-gnu       , features: feat_os_windows } ## note: requires rust >= 1.43.0 to link correctly
           - { os: windows-latest , target: x86_64-pc-windows-msvc      , features: feat_os_windows }
     steps:
-    - uses: actions/checkout@v2
+    - uses: actions/checkout@v3
     - uses: Swatinem/rust-cache@v1
     - name: Initialize workflow variables
       id: vars
@@ -762,7 +762,7 @@ jobs:
         args: --target=${{ matrix.job.target }} ${{ steps.vars.outputs.CARGO_TEST_OPTIONS}} ${{ matrix.job.cargo-options }} ${{ steps.dep_vars.outputs.CARGO_UTILITY_LIST_OPTIONS }}
         toolchain: ${{ env.RUST_MIN_SRV }}
     - name: Archive executable artifacts
-      uses: actions/upload-artifact@v2
+      uses: actions/upload-artifact@v3
       with:
         name: ${{ env.PROJECT_NAME }}-${{ matrix.job.target }}
         path: target/${{ matrix.job.target }}/release/${{ env.PROJECT_NAME }}${{ steps.vars.outputs.EXE_suffix }}
@@ -820,7 +820,7 @@ jobs:
         job:
           - { os: ubuntu-latest }
     steps:
-    - uses: actions/checkout@v2
+    - uses: actions/checkout@v3
     - uses: Swatinem/rust-cache@v1
     - name: Install/setup prerequisites
       shell: bash
@@ -857,9 +857,9 @@ jobs:
     env:
       TERMUX: v0.118.0
     steps:
-    - uses: actions/checkout@v2
+    - uses: actions/checkout@v3
     - name: AVD cache
-      uses: actions/cache@v2
+      uses: actions/cache@v3
       id: avd-cache
       with:
         path: |
@@ -911,11 +911,11 @@ jobs:
     env:
       mem: 2048
     steps:
-    - uses: actions/checkout@v2
+    - uses: actions/checkout@v3
     - uses: Swatinem/rust-cache@v1
     - name: Prepare, build and test
       ## spell-checker:ignore (ToDO) sshfs usesh vmactions
-      uses: vmactions/freebsd-vm@v0.1.5
+      uses: vmactions/freebsd-vm@v0.1.6
       with:
         usesh: true
         # sync: sshfs
@@ -979,7 +979,7 @@ jobs:
           - { os: macos-latest   , features: macos }
           - { os: windows-latest , features: windows }
     steps:
-    - uses: actions/checkout@v2
+    - uses: actions/checkout@v3
     - uses: Swatinem/rust-cache@v1
     # - name: Reattach HEAD ## may be needed for accurate code coverage info
     #   run: git checkout ${{ github.head_ref }}
@@ -1100,7 +1100,7 @@ jobs:
         grcov . --output-type lcov --output-path "${COVERAGE_REPORT_FILE}" --branch --ignore build.rs --ignore "vendor/*" --ignore "/*" --ignore "[a-zA-Z]:/*" --excl-br-line "^\s*((debug_)?assert(_eq|_ne)?!|#\[derive\()"
         echo ::set-output name=report::${COVERAGE_REPORT_FILE}
     - name: Upload coverage results (to Codecov.io)
-      uses: codecov/codecov-action@v1
+      uses: codecov/codecov-action@v3
       # if: steps.vars.outputs.HAS_CODECOV_TOKEN
       with:
         # token: ${{ secrets.CODECOV_TOKEN }}

.github/workflows/FixPR.yml

@@ -28,7 +28,7 @@ jobs:
         job:
           - { os: ubuntu-latest , features: feat_os_unix }
     steps:
-    - uses: actions/checkout@v2
+    - uses: actions/checkout@v3
     - uses: Swatinem/rust-cache@v1
     - name: Initialize job variables
       id: vars
@@ -80,7 +80,7 @@ jobs:
         ## * using the 'stable' toolchain is necessary to avoid "unexpected '--filter-platform'" errors
         RUSTUP_TOOLCHAIN=stable cargo-tree tree --locked --all --no-dev-dependencies --no-indent --features ${{ matrix.job.features }} | grep -vE "$PWD" | sort --unique
     - name: Commit any changes (to '${{ env.BRANCH_TARGET }}')
-      uses: EndBug/add-and-commit@v7
+      uses: EndBug/add-and-commit@v9
       with:
         branch: ${{ env.BRANCH_TARGET }}
         default_author: github_actions
@@ -100,7 +100,7 @@ jobs:
         job:
           - { os: ubuntu-latest , features: feat_os_unix }
     steps:
-    - uses: actions/checkout@v2
+    - uses: actions/checkout@v3
     - uses: Swatinem/rust-cache@v1
     - name: Initialize job variables
       id: vars
@@ -130,7 +130,7 @@ jobs:
         # `cargo fmt` of tests
         find tests -name "*.rs" -print0 | xargs -0 cargo fmt --
     - name: Commit any changes (to '${{ env.BRANCH_TARGET }}')
-      uses: EndBug/add-and-commit@v7
+      uses: EndBug/add-and-commit@v9
       with:
         branch: ${{ env.BRANCH_TARGET }}
         default_author: github_actions

.github/workflows/GnuTests.yml

@@ -41,11 +41,11 @@ jobs:
         TEST_FULL_SUMMARY_FILE='gnu-full-result.json'
         outputs SUITE_LOG_FILE TEST_FILESET_PREFIX TEST_FILESET_SUFFIX TEST_LOGS_GLOB TEST_SUMMARY_FILE TEST_FULL_SUMMARY_FILE
     - name: Checkout code (uutil)
-      uses: actions/checkout@v2
+      uses: actions/checkout@v3
       with:
         path: '${{ steps.vars.outputs.path_UUTILS }}'
     - name: Checkout code (GNU coreutils)
-      uses: actions/checkout@v2
+      uses: actions/checkout@v3
       with:
         repository: 'coreutils/coreutils'
         path: '${{ steps.vars.outputs.path_GNU }}'
@@ -146,22 +146,22 @@ jobs:
           # Compress logs before upload (fails otherwise)
           gzip ${{ steps.vars.outputs.TEST_LOGS_GLOB }}
     - name: Reserve SHA1/ID of 'test-summary'
-      uses: actions/upload-artifact@v2
+      uses: actions/upload-artifact@v3
       with:
         name: "${{ steps.summary.outputs.HASH }}"
         path: "${{ steps.vars.outputs.TEST_SUMMARY_FILE }}"
     - name: Reserve test results summary
-      uses: actions/upload-artifact@v2
+      uses: actions/upload-artifact@v3
       with:
         name: test-summary
         path: "${{ steps.vars.outputs.TEST_SUMMARY_FILE }}"
     - name: Reserve test logs
-      uses: actions/upload-artifact@v2
+      uses: actions/upload-artifact@v3
       with:
         name: test-logs
         path: "${{ steps.vars.outputs.TEST_LOGS_GLOB }}"
     - name: Upload full json results
-      uses: actions/upload-artifact@v2
+      uses: actions/upload-artifact@v3
       with:
         name: gnu-full-result.json
         path: ${{ steps.vars.outputs.TEST_FULL_SUMMARY_FILE }}
@@ -229,11 +229,11 @@ jobs:
     runs-on: ubuntu-latest
     steps:
     - name: Checkout code uutil
-      uses: actions/checkout@v2
+      uses: actions/checkout@v3
       with:
         path: 'uutils'
     - name: Checkout GNU coreutils
-      uses: actions/checkout@v2
+      uses: actions/checkout@v3
       with:
         repository: 'coreutils/coreutils'
         path: 'gnu'
@@ -293,7 +293,7 @@ jobs:
         grcov . --output-type lcov --output-path "${COVERAGE_REPORT_FILE}" --branch --ignore build.rs --ignore "vendor/*" --ignore "/*" --ignore "[a-zA-Z]:/*" --excl-br-line "^\s*((debug_)?assert(_eq|_ne)?!|#\[derive\()"
         echo ::set-output name=report::${COVERAGE_REPORT_FILE}
     - name: Upload coverage results (to Codecov.io)
-      uses: codecov/codecov-action@v2
+      uses: codecov/codecov-action@v3
       with:
         file: ${{ steps.coverage.outputs.report }}
         flags: gnutests

Cargo.lock

@@ -273,9 +273,9 @@ dependencies = [
 
 [[package]]
 name = "clap_complete"
-version = "3.1.3"
+version = "3.1.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "1d7ca9141e27e6ebc52e3c378b0c07f3cea52db46ed1cc5861735fb697b56356"
+checksum = "da92e6facd8d73c22745a5d3cbb59bdf8e46e3235c923e516527d8e81eec14a4"
 dependencies = [
  "clap 3.1.15",
 ]
@@ -2027,9 +2027,9 @@ checksum = "8ccb82d61f80a663efe1f787a51b16b5a51e3314d6ac365b08639f52387b33f3"
 
 [[package]]
 name = "unindent"
-version = "0.1.8"
+version = "0.1.9"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "514672a55d7380da379785a4d70ca8386c8883ff7eaae877be4d2081cebe73d8"
+checksum = "52fee519a3e570f7df377a06a1a7775cdbfb7aa460be7e08de2b1f0e69973a44"
 
 [[package]]
 name = "unix_socket"

src/uu/base32/src/base_common.rs

@@ -123,7 +123,12 @@ pub fn base_app<'a>(about: &'a str, usage: &'a str) -> Command<'a> {
         )
         // "multiple" arguments are used to check whether there is more than one
         // file passed in.
-        .arg(Arg::new(options::FILE).index(1).multiple_occurrences(true))
+        .arg(
+            Arg::new(options::FILE)
+                .index(1)
+                .multiple_occurrences(true)
+                .value_hint(clap::ValueHint::FilePath),
+        )
 }
 
 pub fn get_input<'a>(config: &Config, stdin_ref: &'a Stdin) -> UResult<Box<dyn Read + 'a>> {

src/uu/basename/src/basename.rs

@@ -102,6 +102,7 @@ pub fn uu_app<'a>() -> Command<'a> {
         .arg(
             Arg::new(options::NAME)
                 .multiple_occurrences(true)
+                .value_hint(clap::ValueHint::AnyPath)
                 .hide(true),
         )
         .arg(

src/uu/cat/src/cat.rs

@@ -249,7 +249,8 @@ pub fn uu_app<'a>() -> Command<'a> {
         .arg(
             Arg::new(options::FILE)
                 .hide(true)
-                .multiple_occurrences(true),
+                .multiple_occurrences(true)
+                .value_hint(clap::ValueHint::FilePath),
         )
         .arg(
             Arg::new(options::SHOW_ALL)

src/uu/chcon/src/chcon.rs

@@ -197,6 +197,7 @@ pub fn uu_app<'a>() -> Command<'a> {
                 .long(options::REFERENCE)
                 .takes_value(true)
                 .value_name("RFILE")
+                .value_hint(clap::ValueHint::FilePath)
                 .conflicts_with_all(&[options::USER, options::ROLE, options::TYPE, options::RANGE])
                 .help(
                     "Use security context of RFILE, rather than specifying \
@@ -210,6 +211,7 @@ pub fn uu_app<'a>() -> Command<'a> {
                 .long(options::USER)
                 .takes_value(true)
                 .value_name("USER")
+                .value_hint(clap::ValueHint::Username)
                 .help("Set user USER in the target security context.")
                 .allow_invalid_utf8(true),
         )
@@ -294,6 +296,7 @@ pub fn uu_app<'a>() -> Command<'a> {
         .arg(
             Arg::new("FILE")
                 .multiple_occurrences(true)
+                .value_hint(clap::ValueHint::FilePath)
                 .min_values(1)
                 .allow_invalid_utf8(true),
         )

src/uu/chgrp/src/chgrp.rs

@@ -113,6 +113,7 @@ pub fn uu_app<'a>() -> Command<'a> {
             Arg::new(options::REFERENCE)
                 .long(options::REFERENCE)
                 .value_name("RFILE")
+                .value_hint(clap::ValueHint::FilePath)
                 .help("use RFILE's group rather than specifying GROUP values")
                 .takes_value(true)
                 .multiple_occurrences(false),

src/uu/chmod/src/chmod.rs

@@ -157,6 +157,7 @@ pub fn uu_app<'a>() -> Command<'a> {
             Arg::new(options::REFERENCE)
                 .long("reference")
                 .takes_value(true)
+                .value_hint(clap::ValueHint::FilePath)
                 .help("use RFILE's mode instead of MODE values"),
         )
         .arg(
@@ -170,7 +171,8 @@ pub fn uu_app<'a>() -> Command<'a> {
         .arg(
             Arg::new(options::FILE)
                 .required_unless_present(options::MODE)
-                .multiple_occurrences(true),
+                .multiple_occurrences(true)
+                .value_hint(clap::ValueHint::AnyPath),
         )
 }
 

src/uu/chown/src/chown.rs

@@ -134,6 +134,7 @@ pub fn uu_app<'a>() -> Command<'a> {
                 .long(options::REFERENCE)
                 .help("use RFILE's owner and group rather than specifying OWNER:GROUP values")
                 .value_name("RFILE")
+                .value_hint(clap::ValueHint::FilePath)
                 .min_values(1),
         )
         .arg(
@@ -167,17 +168,18 @@ pub fn uu_app<'a>() -> Command<'a> {
         )
 }
 
-/// Parse the username and groupname
+/// Parse the owner/group specifier string into a user ID and a group ID.
 ///
-/// In theory, it should be username:groupname
+/// The `spec` can be of the form:
-/// but ...
-/// it can user.name:groupname
-/// or username.groupname
 ///
-/// # Arguments
+/// * `"owner:group"`,
+/// * `"owner"`,
+/// * `":group"`,
 ///
-/// * `spec` - The input from the user
+/// and the owner or group can be specified either as an ID or a
-/// * `sep` - Should be ':' or '.'
+/// name. The `sep` argument specifies which character to use as a
+/// separator between the owner and group; calling code should set
+/// this to `':'`.
 fn parse_spec(spec: &str, sep: char) -> UResult<(Option<u32>, Option<u32>)> {
     assert!(['.', ':'].contains(&sep));
     let mut args = spec.splitn(2, sep);
@@ -197,10 +199,17 @@ fn parse_spec(spec: &str, sep: char) -> UResult<(Option<u32>, Option<u32>)> {
                     // So, try to parse it this way
                     return parse_spec(spec, '.');
                 } else {
-                    return Err(USimpleError::new(
+                    // It's possible that the `user` string contains a
-                        1,
+                    // numeric user ID, in which case, we respect that.
-                        format!("invalid user: {}", spec.quote()),
+                    match user.parse() {
-                    ));
+                        Ok(uid) => uid,
+                        Err(_) => {
+                            return Err(USimpleError::new(
+                                1,
+                                format!("invalid user: {}", spec.quote()),
+                            ))
+                        }
+                    }
                 }
             }
         })
@@ -208,11 +217,18 @@ fn parse_spec(spec: &str, sep: char) -> UResult<(Option<u32>, Option<u32>)> {
         None
     };
     let gid = if !group.is_empty() {
-        Some(
+        Some(match Group::locate(group) {
-            Group::locate(group)
+            Ok(g) => g.gid,
-                .map_err(|_| USimpleError::new(1, format!("invalid group: {}", spec.quote())))?
+            Err(_) => match group.parse() {
-                .gid,
+                Ok(gid) => gid,
-        )
+                Err(_) => {
+                    return Err(USimpleError::new(
+                        1,
+                        format!("invalid group: {}", spec.quote()),
+                    ));
+                }
+            },
+        })
     } else {
         None
     };
@@ -231,4 +247,17 @@ mod test {
         assert!(format!("{}", parse_spec("::", ':').err().unwrap()).starts_with("invalid group: "));
         assert!(format!("{}", parse_spec("..", ':').err().unwrap()).starts_with("invalid group: "));
     }
+
+    /// Test for parsing IDs that don't correspond to a named user or group.
+    #[test]
+    fn test_parse_spec_nameless_ids() {
+        // This assumes that there is no named user with ID 12345.
+        assert!(matches!(parse_spec("12345", ':'), Ok((Some(12345), None))));
+        // This assumes that there is no named group with ID 54321.
+        assert!(matches!(parse_spec(":54321", ':'), Ok((None, Some(54321)))));
+        assert!(matches!(
+            parse_spec("12345:54321", ':'),
+            Ok((Some(12345), Some(54321)))
+        ));
+    }
 }

src/uu/chroot/src/chroot.rs

@@ -102,6 +102,7 @@ pub fn uu_app<'a>() -> Command<'a> {
         .infer_long_args(true)
         .arg(
             Arg::new(options::NEWROOT)
+                .value_hint(clap::ValueHint::DirPath)
                 .hide(true)
                 .required(true)
                 .index(1),
@@ -139,6 +140,7 @@ pub fn uu_app<'a>() -> Command<'a> {
         )
         .arg(
             Arg::new(options::COMMAND)
+                .value_hint(clap::ValueHint::CommandName)
                 .hide(true)
                 .multiple_occurrences(true)
                 .index(2),

src/uu/cksum/src/cksum.rs

@@ -150,6 +150,7 @@ pub fn uu_app<'a>() -> Command<'a> {
         .arg(
             Arg::new(options::FILE)
                 .hide(true)
-                .multiple_occurrences(true),
+                .multiple_occurrences(true)
+                .value_hint(clap::ValueHint::FilePath),
         )
 }

src/uu/comm/src/comm.rs

@@ -173,6 +173,14 @@ pub fn uu_app<'a>() -> Command<'a> {
                 .default_value(options::DELIMITER_DEFAULT)
                 .hide_default_value(true),
         )
-        .arg(Arg::new(options::FILE_1).required(true))
+        .arg(
-        .arg(Arg::new(options::FILE_2).required(true))
+            Arg::new(options::FILE_1)
+                .required(true)
+                .value_hint(clap::ValueHint::FilePath),
+        )
+        .arg(
+            Arg::new(options::FILE_2)
+                .required(true)
+                .value_hint(clap::ValueHint::FilePath),
+        )
 }

src/uu/cp/src/cp.rs

@@ -314,6 +314,7 @@ pub fn uu_app<'a>() -> Command<'a> {
              .conflicts_with(options::NO_TARGET_DIRECTORY)
              .long(options::TARGET_DIRECTORY)
              .value_name(options::TARGET_DIRECTORY)
+             .value_hint(clap::ValueHint::DirPath)
              .takes_value(true)
              .validator(|s| {
                  if Path::new(s).is_dir() {
@@ -464,7 +465,8 @@ pub fn uu_app<'a>() -> Command<'a> {
         // END TODO
 
         .arg(Arg::new(options::PATHS)
-             .multiple_occurrences(true))
+             .multiple_occurrences(true)
+             .value_hint(clap::ValueHint::AnyPath))
 }
 
 #[uucore::main]

src/uu/csplit/src/csplit.rs

@@ -797,7 +797,12 @@ pub fn uu_app<'a>() -> Command<'a> {
                 .long(options::ELIDE_EMPTY_FILES)
                 .help("remove empty output files"),
         )
-        .arg(Arg::new(options::FILE).hide(true).required(true))
+        .arg(
+            Arg::new(options::FILE)
+                .hide(true)
+                .required(true)
+                .value_hint(clap::ValueHint::FilePath),
+        )
         .arg(
             Arg::new(options::PATTERN)
                 .hide(true)

src/uu/cut/src/cut.rs

@@ -614,6 +614,7 @@ pub fn uu_app<'a>() -> Command<'a> {
         .arg(
             Arg::new(options::FILE)
             .hide(true)
-                .multiple_occurrences(true)
+            .multiple_occurrences(true)
+            .value_hint(clap::ValueHint::FilePath)
         )
 }

src/uu/date/src/date.rs

@@ -272,6 +272,7 @@ pub fn uu_app<'a>() -> Command<'a> {
                 .short('f')
                 .long(OPT_FILE)
                 .takes_value(true)
+                .value_hint(clap::ValueHint::FilePath)
                 .help("like --date; once for each line of DATEFILE"),
         )
         .arg(
@@ -303,6 +304,7 @@ pub fn uu_app<'a>() -> Command<'a> {
                 .short('r')
                 .long(OPT_REFERENCE)
                 .takes_value(true)
+                .value_hint(clap::ValueHint::AnyPath)
                 .help("display the last modification time of FILE"),
         )
         .arg(

src/uu/dd/src/dd.rs

@@ -742,6 +742,7 @@ pub fn uu_app<'a>() -> Command<'a> {
                 .long(options::INFILE)
                 .overrides_with(options::INFILE)
                 .takes_value(true)
+                .value_hint(clap::ValueHint::FilePath)
                 .require_equals(true)
                 .value_name("FILE")
                 .help("(alternatively if=FILE) specifies the file used for input. When not specified, stdin is used instead")
@@ -751,6 +752,7 @@ pub fn uu_app<'a>() -> Command<'a> {
                 .long(options::OUTFILE)
                 .overrides_with(options::OUTFILE)
                 .takes_value(true)
+                .value_hint(clap::ValueHint::FilePath)
                 .require_equals(true)
                 .value_name("FILE")
                 .help("(alternatively of=FILE) specifies the file used for output. When not specified, stdout is used instead")

src/uu/df/src/blocks.rs

@@ -7,7 +7,10 @@ use crate::OPT_BLOCKSIZE;
 use clap::ArgMatches;
 use std::{env, fmt};
 
-use uucore::parse_size::{parse_size, ParseSizeError};
+use uucore::{
+    display::Quotable,
+    parse_size::{parse_size, ParseSizeError},
+};
 
 /// The first ten powers of 1024.
 const IEC_BASES: [u128; 10] = [
@@ -167,6 +170,15 @@ pub(crate) enum BlockSize {
     Bytes(u64),
 }
 
+impl BlockSize {
+    /// Returns the associated value
+    pub(crate) fn as_u64(&self) -> u64 {
+        match *self {
+            Self::Bytes(n) => n,
+        }
+    }
+}
+
 impl Default for BlockSize {
     fn default() -> Self {
         if env::var("POSIXLY_CORRECT").is_ok() {
@@ -180,7 +192,13 @@ impl Default for BlockSize {
 pub(crate) fn block_size_from_matches(matches: &ArgMatches) -> Result<BlockSize, ParseSizeError> {
     if matches.is_present(OPT_BLOCKSIZE) {
         let s = matches.value_of(OPT_BLOCKSIZE).unwrap();
-        Ok(BlockSize::Bytes(parse_size(s)?))
+        let bytes = parse_size(s)?;
+
+        if bytes > 0 {
+            Ok(BlockSize::Bytes(bytes))
+        } else {
+            Err(ParseSizeError::ParseFailure(format!("{}", s.quote())))
+        }
     } else {
         Ok(Default::default())
     }

src/uu/df/src/df.rs

@@ -12,6 +12,7 @@ mod filesystem;
 mod table;
 
 use blocks::{HumanReadable, SizeFormat};
+use table::HeaderMode;
 use uucore::display::Quotable;
 use uucore::error::{UError, UResult, USimpleError};
 use uucore::fsext::{read_fs_list, MountInfo};
@@ -72,6 +73,7 @@ struct Options {
     show_all_fs: bool,
     size_format: SizeFormat,
     block_size: BlockSize,
+    header_mode: HeaderMode,
 
     /// Optional list of filesystem types to include in the output table.
     ///
@@ -99,6 +101,7 @@ impl Default for Options {
             show_all_fs: Default::default(),
             block_size: Default::default(),
             size_format: Default::default(),
+            header_mode: Default::default(),
             include: Default::default(),
             exclude: Default::default(),
             show_total: Default::default(),
@@ -176,6 +179,21 @@ impl Options {
                 ),
                 ParseSizeError::ParseFailure(s) => OptionsError::InvalidBlockSize(s),
             })?,
+            header_mode: {
+                if matches.is_present(OPT_HUMAN_READABLE_BINARY)
+                    || matches.is_present(OPT_HUMAN_READABLE_DECIMAL)
+                {
+                    HeaderMode::HumanReadable
+                } else if matches.is_present(OPT_PORTABILITY) {
+                    HeaderMode::PosixPortability
+                // is_present() doesn't work here, it always returns true because OPT_OUTPUT has
+                // default values and hence is always present
+                } else if matches.occurrences_of(OPT_OUTPUT) > 0 {
+                    HeaderMode::Output
+                } else {
+                    HeaderMode::Default
+                }
+            },
             size_format: {
                 if matches.is_present(OPT_HUMAN_READABLE_BINARY) {
                     SizeFormat::HumanReadable(HumanReadable::Binary)
@@ -565,7 +583,11 @@ pub fn uu_app<'a>() -> Command<'a> {
                 .multiple_occurrences(true)
                 .help("limit listing to file systems not of type TYPE"),
         )
-        .arg(Arg::new(OPT_PATHS).multiple_occurrences(true))
+        .arg(
+            Arg::new(OPT_PATHS)
+                .multiple_occurrences(true)
+                .value_hint(clap::ValueHint::AnyPath),
+        )
 }
 
 #[cfg(test)]

src/uu/df/src/table.rs

@@ -233,7 +233,7 @@ impl<'a> RowFormatter<'a> {
             SizeFormat::HumanReadable(h) => self.scaled_human_readable(size, h),
             SizeFormat::StaticBlockSize => {
                 let BlockSize::Bytes(d) = self.options.block_size;
-                (size / d).to_string()
+                (size as f64 / d as f64).ceil().to_string()
             }
         }
     }
@@ -289,6 +289,23 @@ impl<'a> RowFormatter<'a> {
     }
 }
 
+/// A HeaderMode defines what header labels should be shown.
+pub(crate) enum HeaderMode {
+    Default,
+    // the user used -h or -H
+    HumanReadable,
+    // the user used -P
+    PosixPortability,
+    // the user used --output
+    Output,
+}
+
+impl Default for HeaderMode {
+    fn default() -> Self {
+        Self::Default
+    }
+}
+
 /// The data of the header row.
 struct Header {}
 
@@ -302,15 +319,22 @@ impl Header {
         for column in &options.columns {
             let header = match column {
                 Column::Source => String::from("Filesystem"),
-                Column::Size => match options.size_format {
+                Column::Size => match options.header_mode {
-                    SizeFormat::HumanReadable(_) => String::from("Size"),
+                    HeaderMode::HumanReadable => String::from("Size"),
-                    SizeFormat::StaticBlockSize => {
+                    HeaderMode::PosixPortability => {
-                        format!("{}-blocks", options.block_size)
+                        format!("{}-blocks", options.block_size.as_u64())
                     }
+                    _ => format!("{}-blocks", options.block_size),
                 },
                 Column::Used => String::from("Used"),
-                Column::Avail => String::from("Available"),
+                Column::Avail => match options.header_mode {
-                Column::Pcent => String::from("Use%"),
+                    HeaderMode::HumanReadable | HeaderMode::Output => String::from("Avail"),
+                    _ => String::from("Available"),
+                },
+                Column::Pcent => match options.header_mode {
+                    HeaderMode::PosixPortability => String::from("Capacity"),
+                    _ => String::from("Use%"),
+                },
                 Column::Target => String::from("Mounted on"),
                 Column::Itotal => String::from("Inodes"),
                 Column::Iused => String::from("IUsed"),
@@ -428,7 +452,7 @@ mod tests {
 
     use crate::blocks::{HumanReadable, SizeFormat};
     use crate::columns::Column;
-    use crate::table::{Header, Row, RowFormatter};
+    use crate::table::{Header, HeaderMode, Row, RowFormatter};
     use crate::{BlockSize, Options};
 
     const COLUMNS_WITH_FS_TYPE: [Column; 7] = [
@@ -548,37 +572,49 @@ mod tests {
     }
 
     #[test]
-    fn test_header_with_human_readable_binary() {
+    fn test_human_readable_header() {
         let options = Options {
-            size_format: SizeFormat::HumanReadable(HumanReadable::Binary),
+            header_mode: HeaderMode::HumanReadable,
+            ..Default::default()
+        };
+        assert_eq!(
+            Header::get_headers(&options),
+            vec!("Filesystem", "Size", "Used", "Avail", "Use%", "Mounted on")
+        );
+    }
+
+    #[test]
+    fn test_posix_portability_header() {
+        let options = Options {
+            header_mode: HeaderMode::PosixPortability,
             ..Default::default()
         };
         assert_eq!(
             Header::get_headers(&options),
             vec!(
                 "Filesystem",
-                "Size",
+                "1024-blocks",
                 "Used",
                 "Available",
-                "Use%",
+                "Capacity",
                 "Mounted on"
             )
         );
     }
 
     #[test]
-    fn test_header_with_human_readable_si() {
+    fn test_output_header() {
         let options = Options {
-            size_format: SizeFormat::HumanReadable(HumanReadable::Decimal),
+            header_mode: HeaderMode::Output,
             ..Default::default()
         };
         assert_eq!(
             Header::get_headers(&options),
             vec!(
                 "Filesystem",
-                "Size",
+                "1K-blocks",
                 "Used",
-                "Available",
+                "Avail",
                 "Use%",
                 "Mounted on"
             )
@@ -757,4 +793,28 @@ mod tests {
         let fmt = RowFormatter::new(&row, &options);
         assert_eq!(fmt.get_values(), vec!("26%"));
     }
+
+    #[test]
+    fn test_row_formatter_with_round_up_byte_values() {
+        fn get_formatted_values(bytes: u64, bytes_used: u64, bytes_avail: u64) -> Vec<String> {
+            let options = Options {
+                block_size: BlockSize::Bytes(1000),
+                columns: vec![Column::Size, Column::Used, Column::Avail],
+                ..Default::default()
+            };
+
+            let row = Row {
+                bytes,
+                bytes_used,
+                bytes_avail,
+                ..Default::default()
+            };
+            RowFormatter::new(&row, &options).get_values()
+        }
+
+        assert_eq!(get_formatted_values(100, 100, 0), vec!("1", "1", "0"));
+        assert_eq!(get_formatted_values(100, 99, 1), vec!("1", "1", "1"));
+        assert_eq!(get_formatted_values(1000, 1000, 0), vec!("1", "1", "0"));
+        assert_eq!(get_formatted_values(1001, 1000, 1), vec!("2", "1", "1"));
+    }
 }

src/uu/dircolors/src/dircolors.rs

@@ -187,6 +187,7 @@ pub fn uu_app<'a>() -> Command<'a> {
         .arg(
             Arg::new(options::FILE)
                 .hide(true)
+                .value_hint(clap::ValueHint::FilePath)
                 .multiple_occurrences(true),
         )
 }

src/uu/dirname/src/dirname.rs

@@ -88,5 +88,10 @@ pub fn uu_app<'a>() -> Command<'a> {
                 .short('z')
                 .help("separate output with NUL rather than newline"),
         )
-        .arg(Arg::new(options::DIR).hide(true).multiple_occurrences(true))
+        .arg(
+            Arg::new(options::DIR)
+                .hide(true)
+                .multiple_occurrences(true)
+                .value_hint(clap::ValueHint::AnyPath),
+        )
 }

src/uu/du/src/du.rs

@@ -884,6 +884,7 @@ pub fn uu_app<'a>() -> Command<'a> {
                 .short('X')
                 .long("exclude-from")
                 .value_name("FILE")
+                .value_hint(clap::ValueHint::FilePath)
                 .help("exclude files that match any pattern in FILE")
                 .multiple_occurrences(true)
 
@@ -913,6 +914,7 @@ pub fn uu_app<'a>() -> Command<'a> {
         .arg(
             Arg::new(options::FILE)
                 .hide(true)
+                .value_hint(clap::ValueHint::AnyPath)
                 .multiple_occurrences(true)
         )
 }

src/uu/env/src/env.rs

@@ -144,6 +144,7 @@ pub fn uu_app<'a>() -> Command<'a> {
             .takes_value(true)
             .number_of_values(1)
             .value_name("DIR")
+            .value_hint(clap::ValueHint::DirPath)
             .help("change working directory to DIR"))
         .arg(Arg::new("null")
             .short('0')
@@ -156,6 +157,7 @@ pub fn uu_app<'a>() -> Command<'a> {
             .takes_value(true)
             .number_of_values(1)
             .value_name("PATH")
+            .value_hint(clap::ValueHint::FilePath)
             .multiple_occurrences(true)
             .help("read and set variables from a \".env\"-style configuration file (prior to any \
                     unset and/or set)"))

src/uu/expand/src/expand.rs

@@ -207,6 +207,7 @@ pub fn uu_app<'a>() -> Command<'a> {
                 .multiple_occurrences(true)
                 .hide(true)
                 .takes_value(true)
+                .value_hint(clap::ValueHint::FilePath)
         )
 }
 

src/uu/fmt/src/fmt.rs

@@ -344,6 +344,7 @@ pub fn uu_app<'a>() -> Command<'a> {
         .arg(
             Arg::new(ARG_FILES)
                 .multiple_occurrences(true)
-                .takes_value(true),
+                .takes_value(true)
+                .value_hint(clap::ValueHint::FilePath),
         )
 }

src/uu/fold/src/fold.rs

@@ -99,7 +99,8 @@ pub fn uu_app<'a>() -> Command<'a> {
         .arg(
             Arg::new(options::FILE)
                 .hide(true)
-                .multiple_occurrences(true),
+                .multiple_occurrences(true)
+                .value_hint(clap::ValueHint::FilePath),
         )
 }
 

src/uu/groups/src/groups.rs

@@ -112,6 +112,7 @@ pub fn uu_app<'a>() -> Command<'a> {
             Arg::new(options::USERS)
                 .multiple_occurrences(true)
                 .takes_value(true)
-                .value_name(options::USERS),
+                .value_name(options::USERS)
+                .value_hint(clap::ValueHint::Username),
         )
 }

src/uu/hashsum/src/hashsum.rs

@@ -423,6 +423,7 @@ pub fn uu_app_common<'a>() -> Command<'a> {
                 .index(1)
                 .multiple_occurrences(true)
                 .value_name("FILE")
+                .value_hint(clap::ValueHint::FilePath)
                 .allow_invalid_utf8(true),
         )
 }

src/uu/head/src/head.rs

@@ -107,7 +107,11 @@ pub fn uu_app<'a>() -> Command<'a> {
                 .help("line delimiter is NUL, not newline")
                 .overrides_with(options::ZERO_NAME),
         )
-        .arg(Arg::new(options::FILES_NAME).multiple_occurrences(true))
+        .arg(
+            Arg::new(options::FILES_NAME)
+                .multiple_occurrences(true)
+                .value_hint(clap::ValueHint::FilePath),
+        )
 }
 
 #[derive(Debug, PartialEq)]

src/uu/hostname/src/hostname.rs

@@ -105,7 +105,11 @@ pub fn uu_app<'a>() -> Command<'a> {
                 .overrides_with_all(&[OPT_DOMAIN, OPT_IP_ADDRESS, OPT_FQDN, OPT_SHORT])
                 .help("Display the short hostname (the portion before the first dot) if possible"),
         )
-        .arg(Arg::new(OPT_HOST).allow_invalid_utf8(true))
+        .arg(
+            Arg::new(OPT_HOST)
+                .allow_invalid_utf8(true)
+                .value_hint(clap::ValueHint::Hostname),
+        )
 }
 
 fn display_hostname(matches: &ArgMatches) -> UResult<()> {

src/uu/id/src/id.rs

@@ -443,7 +443,8 @@ pub fn uu_app<'a>() -> Command<'a> {
             Arg::new(options::ARG_USERS)
                 .multiple_occurrences(true)
                 .takes_value(true)
-                .value_name(options::ARG_USERS),
+                .value_name(options::ARG_USERS)
+                .value_hint(clap::ValueHint::Username),
         )
 }
 

src/uu/install/src/install.rs

@@ -248,6 +248,7 @@ pub fn uu_app<'a>() -> Command<'a> {
                 .help("set ownership (super-user only)")
                 .value_name("OWNER")
                 .takes_value(true)
+                .value_hint(clap::ValueHint::Username)
         )
         .arg(
             Arg::new(OPT_PRESERVE_TIMESTAMPS)
@@ -266,6 +267,7 @@ pub fn uu_app<'a>() -> Command<'a> {
                 .long(OPT_STRIP_PROGRAM)
                 .help("program used to strip binaries (no action Windows)")
                 .value_name("PROGRAM")
+                .value_hint(clap::ValueHint::CommandName)
         )
         .arg(
             backup_control::arguments::suffix()
@@ -277,6 +279,7 @@ pub fn uu_app<'a>() -> Command<'a> {
                 .long(OPT_TARGET_DIRECTORY)
                 .help("move all SOURCE arguments into DIRECTORY")
                 .value_name("DIRECTORY")
+                .value_hint(clap::ValueHint::DirPath)
         )
         .arg(
             // TODO implement flag
@@ -307,7 +310,13 @@ pub fn uu_app<'a>() -> Command<'a> {
                 .help("(unimplemented) set security context of files and directories")
                 .value_name("CONTEXT")
         )
-        .arg(Arg::new(ARG_FILES).multiple_occurrences(true).takes_value(true).min_values(1))
+        .arg(
+            Arg::new(ARG_FILES)
+                .multiple_occurrences(true)
+                .takes_value(true)
+                .min_values(1)
+                .value_hint(clap::ValueHint::AnyPath)
+        )
 }
 
 /// Check for unimplemented command line arguments.

src/uu/join/src/join.rs

@@ -801,12 +801,14 @@ FILENUM is 1 or 2, corresponding to FILE1 or FILE2",
             Arg::new("file1")
                 .required(true)
                 .value_name("FILE1")
+                .value_hint(clap::ValueHint::FilePath)
                 .hide(true),
         )
         .arg(
             Arg::new("file2")
                 .required(true)
                 .value_name("FILE2")
+                .value_hint(clap::ValueHint::FilePath)
                 .hide(true),
         )
 }

src/uu/link/src/link.rs

@@ -46,6 +46,7 @@ pub fn uu_app<'a>() -> Command<'a> {
                 .min_values(2)
                 .max_values(2)
                 .takes_value(true)
+                .value_hint(clap::ValueHint::AnyPath)
                 .allow_invalid_utf8(true),
         )
 }

src/uu/ln/src/ln.rs

@@ -232,6 +232,7 @@ pub fn uu_app<'a>() -> Command<'a> {
                 .long(options::TARGET_DIRECTORY)
                 .help("specify the DIRECTORY in which to create the links")
                 .value_name("DIRECTORY")
+                .value_hint(clap::ValueHint::DirPath)
                 .conflicts_with(options::NO_TARGET_DIRECTORY),
         )
         .arg(
@@ -257,6 +258,7 @@ pub fn uu_app<'a>() -> Command<'a> {
             Arg::new(ARG_FILES)
                 .multiple_occurrences(true)
                 .takes_value(true)
+                .value_hint(clap::ValueHint::AnyPath)
                 .required(true)
                 .min_values(1),
         )

src/uu/ls/src/ls.rs

@@ -1402,7 +1402,8 @@ pub fn uu_app<'a>() -> Command<'a> {
                 Arg::new(options::PATHS)
                     .multiple_occurrences(true)
                     .takes_value(true)
-                    .allow_invalid_utf8(true),
+                    .value_hint(clap::ValueHint::AnyPath)
+                    .allow_invalid_utf8(true)
             )
             .after_help(
                 "The TIME_STYLE argument can be full-iso, long-iso, iso. \

src/uu/mkdir/src/mkdir.rs

@@ -137,7 +137,8 @@ pub fn uu_app<'a>() -> Command<'a> {
                 .multiple_occurrences(true)
                 .takes_value(true)
                 .min_values(1)
-                .allow_invalid_utf8(true),
+                .allow_invalid_utf8(true)
+                .value_hint(clap::ValueHint::DirPath),
         )
 }
 

src/uu/mkfifo/src/mkfifo.rs

@@ -102,6 +102,7 @@ pub fn uu_app<'a>() -> Command<'a> {
         .arg(
             Arg::new(options::FIFO)
                 .hide(true)
-                .multiple_occurrences(true),
+                .multiple_occurrences(true)
+                .value_hint(clap::ValueHint::AnyPath),
         )
 }

src/uu/mknod/src/mknod.rs

@@ -162,7 +162,8 @@ pub fn uu_app<'a>() -> Command<'a> {
                 .value_name("NAME")
                 .help("name of the new file")
                 .required(true)
-                .index(1),
+                .index(1)
+                .value_hint(clap::ValueHint::AnyPath),
         )
         .arg(
             Arg::new("type")

src/uu/mktemp/src/mktemp.rs

@@ -13,12 +13,16 @@ use uucore::display::{println_verbatim, Quotable};
 use uucore::error::{FromIo, UError, UResult};
 use uucore::format_usage;
 
+use std::env;
 use std::error::Error;
 use std::fmt::Display;
 use std::iter;
-use std::os::unix::prelude::PermissionsExt;
 use std::path::{is_separator, Path, PathBuf};
-use std::{env, fs};
+
+#[cfg(unix)]
+use std::fs;
+#[cfg(unix)]
+use std::os::unix::prelude::PermissionsExt;
 
 use rand::Rng;
 use tempfile::Builder;
@@ -42,7 +46,12 @@ enum MkTempError {
     PersistError(PathBuf),
     MustEndInX(String),
     TooFewXs(String),
-    ContainsDirSeparator(String),
+
+    /// The template prefix contains a path separator (e.g. `"a/bXXX"`).
+    PrefixContainsDirSeparator(String),
+
+    /// The template suffix contains a path separator (e.g. `"XXXa/b"`).
+    SuffixContainsDirSeparator(String),
     InvalidTemplate(String),
 }
 
@@ -57,7 +66,14 @@ impl Display for MkTempError {
             PersistError(p) => write!(f, "could not persist file {}", p.quote()),
             MustEndInX(s) => write!(f, "with --suffix, template {} must end in X", s.quote()),
             TooFewXs(s) => write!(f, "too few X's in template {}", s.quote()),
-            ContainsDirSeparator(s) => {
+            PrefixContainsDirSeparator(s) => {
+                write!(
+                    f,
+                    "invalid template, {}, contains directory separator",
+                    s.quote()
+                )
+            }
+            SuffixContainsDirSeparator(s) => {
                 write!(
                     f,
                     "invalid suffix {}, contains directory separator",
@@ -191,7 +207,8 @@ pub fn uu_app<'a>() -> Command<'a> {
                      be an absolute name; unlike with -t, TEMPLATE may contain \
                      slashes, but mktemp creates only the final component",
                 )
-                .value_name("DIR"),
+                .value_name("DIR")
+                .value_hint(clap::ValueHint::DirPath),
         )
         .arg(Arg::new(OPT_T).short('t').help(
             "Generate a template (using the supplied prefix and TMPDIR (TMP on windows) if set) \
@@ -253,8 +270,12 @@ fn parse_template<'a>(
         }
     };
 
+    if prefix.chars().any(is_separator) {
+        return Err(MkTempError::PrefixContainsDirSeparator(temp.into()));
+    }
+
     if suf.chars().any(is_separator) {
-        return Err(MkTempError::ContainsDirSeparator(suf.into()));
+        return Err(MkTempError::SuffixContainsDirSeparator(suf.into()));
     }
 
     Ok((prefix, rand, suf))
@@ -358,11 +379,7 @@ mod tests {
 
     #[test]
     fn test_parse_template_errors() {
-        // TODO This should be an error as well, but we are not
+        assert!(parse_template("a/bXXX", None).is_err());
-        // catching it just yet. A future commit will correct this.
-        //
-        //     assert!(parse_template("a/bXXX", None).is_err());
-        //
         assert!(parse_template("XXXa/b", None).is_err());
         assert!(parse_template("XX", None).is_err());
         assert!(parse_template("XXXabc", Some("def")).is_err());

src/uu/more/src/more.rs

@@ -183,7 +183,8 @@ pub fn uu_app<'a>() -> Command<'a> {
             Arg::new(options::FILES)
                 .required(false)
                 .multiple_occurrences(true)
-                .help("Path to the files to be read"),
+                .help("Path to the files to be read")
+                .value_hint(clap::ValueHint::FilePath),
         )
 }
 

src/uu/mv/src/mv.rs

@@ -156,14 +156,15 @@ pub fn uu_app<'a>() -> Command<'a> {
         .help("move all SOURCE arguments into DIRECTORY")
         .takes_value(true)
         .value_name("DIRECTORY")
+        .value_hint(clap::ValueHint::DirPath)
         .conflicts_with(OPT_NO_TARGET_DIRECTORY)
         .allow_invalid_utf8(true)
     )
     .arg(
             Arg::new(OPT_NO_TARGET_DIRECTORY)
             .short('T')
-            .long(OPT_NO_TARGET_DIRECTORY).
+            .long(OPT_NO_TARGET_DIRECTORY)
-            help("treat DEST as a normal file")
+            .help("treat DEST as a normal file")
     )
     .arg(
             Arg::new(OPT_UPDATE)
@@ -183,6 +184,7 @@ pub fn uu_app<'a>() -> Command<'a> {
             .min_values(2)
             .required(true)
             .allow_invalid_utf8(true)
+            .value_hint(clap::ValueHint::AnyPath)
         )
 }
 

src/uu/nice/src/nice.rs

@@ -117,5 +117,9 @@ pub fn uu_app<'a>() -> Command<'a> {
                 .takes_value(true)
                 .allow_hyphen_values(true),
         )
-        .arg(Arg::new(options::COMMAND).multiple_occurrences(true))
+        .arg(
+            Arg::new(options::COMMAND)
+                .multiple_occurrences(true)
+                .value_hint(clap::ValueHint::CommandName),
+        )
 }

src/uu/nl/src/nl.rs

@@ -154,7 +154,8 @@ pub fn uu_app<'a>() -> Command<'a> {
         .arg(
             Arg::new(options::FILE)
                 .hide(true)
-                .multiple_occurrences(true),
+                .multiple_occurrences(true)
+                .value_hint(clap::ValueHint::FilePath),
         )
         .arg(
             Arg::new(options::BODY_NUMBERING)

src/uu/nohup/src/nohup.rs

@@ -126,7 +126,8 @@ pub fn uu_app<'a>() -> Command<'a> {
             Arg::new(options::CMD)
                 .hide(true)
                 .required(true)
-                .multiple_occurrences(true),
+                .multiple_occurrences(true)
+                .value_hint(clap::ValueHint::CommandName),
         )
         .trailing_var_arg(true)
         .infer_long_args(true)

src/uu/od/src/od.rs

@@ -512,7 +512,8 @@ pub fn uu_app<'a>() -> Command<'a> {
         .arg(
             Arg::new(options::FILENAME)
                 .hide(true)
-                .multiple_occurrences(true),
+                .multiple_occurrences(true)
+                .value_hint(clap::ValueHint::FilePath),
         )
 }
 

src/uu/paste/src/paste.rs

@@ -71,7 +71,8 @@ pub fn uu_app<'a>() -> Command<'a> {
             Arg::new(options::FILE)
                 .value_name("FILE")
                 .multiple_occurrences(true)
-                .default_value("-"),
+                .default_value("-")
+                .value_hint(clap::ValueHint::FilePath),
         )
 }
 

src/uu/pathchk/src/pathchk.rs

@@ -108,7 +108,8 @@ pub fn uu_app<'a>() -> Command<'a> {
         .arg(
             Arg::new(options::PATH)
                 .hide(true)
-                .multiple_occurrences(true),
+                .multiple_occurrences(true)
+                .value_hint(clap::ValueHint::AnyPath),
         )
 }
 

src/uu/pinky/src/pinky.rs

@@ -179,7 +179,8 @@ pub fn uu_app<'a>() -> Command<'a> {
         .arg(
             Arg::new(options::USER)
                 .takes_value(true)
-                .multiple_occurrences(true),
+                .multiple_occurrences(true)
+                .value_hint(clap::ValueHint::Username),
         )
         .arg(
             // Redefine the help argument to not include the short flag

src/uu/pr/src/pr.rs

@@ -372,6 +372,7 @@ pub fn uu_app<'a>() -> Command<'a> {
             Arg::new(options::FILES)
                 .multiple_occurrences(true)
                 .multiple_values(true)
+                .value_hint(clap::ValueHint::FilePath)
         )
 }
 

src/uu/ptx/src/ptx.rs

@@ -754,7 +754,8 @@ pub fn uu_app<'a>() -> Command<'a> {
         .arg(
             Arg::new(options::FILE)
                 .hide(true)
-                .multiple_occurrences(true),
+                .multiple_occurrences(true)
+                .value_hint(clap::ValueHint::FilePath),
         )
         .arg(
             Arg::new(options::AUTO_REFERENCE)
@@ -826,7 +827,8 @@ pub fn uu_app<'a>() -> Command<'a> {
                 .long(options::BREAK_FILE)
                 .help("word break characters in this FILE")
                 .value_name("FILE")
-                .takes_value(true),
+                .takes_value(true)
+                .value_hint(clap::ValueHint::FilePath),
         )
         .arg(
             Arg::new(options::IGNORE_CASE)
@@ -849,7 +851,8 @@ pub fn uu_app<'a>() -> Command<'a> {
                 .long(options::IGNORE_FILE)
                 .help("read ignore word list from FILE")
                 .value_name("FILE")
-                .takes_value(true),
+                .takes_value(true)
+                .value_hint(clap::ValueHint::FilePath),
         )
         .arg(
             Arg::new(options::ONLY_FILE)
@@ -857,7 +860,8 @@ pub fn uu_app<'a>() -> Command<'a> {
                 .long(options::ONLY_FILE)
                 .help("read only word list from this FILE")
                 .value_name("FILE")
-                .takes_value(true),
+                .takes_value(true)
+                .value_hint(clap::ValueHint::FilePath),
         )
         .arg(
             Arg::new(options::REFERENCES)

src/uu/readlink/src/readlink.rs

@@ -161,7 +161,8 @@ pub fn uu_app<'a>() -> Command<'a> {
         .arg(
             Arg::new(ARG_FILES)
                 .multiple_occurrences(true)
-                .takes_value(true),
+                .takes_value(true)
+                .value_hint(clap::ValueHint::AnyPath),
         )
 }
 

src/uu/realpath/src/realpath.rs

@@ -130,7 +130,8 @@ pub fn uu_app<'a>() -> Command<'a> {
                 .multiple_occurrences(true)
                 .takes_value(true)
                 .required(true)
-                .min_values(1),
+                .min_values(1)
+                .value_hint(clap::ValueHint::AnyPath),
         )
 }
 

src/uu/relpath/src/relpath.rs

@@ -87,6 +87,15 @@ pub fn uu_app<'a>() -> Command<'a> {
         .arg(Arg::new(options::DIR).short('d').takes_value(true).help(
             "If any of FROM and TO is not subpath of DIR, output absolute path instead of relative",
         ))
-        .arg(Arg::new(options::TO).required(true).takes_value(true))
+        .arg(
-        .arg(Arg::new(options::FROM).takes_value(true))
+            Arg::new(options::TO)
+                .required(true)
+                .takes_value(true)
+                .value_hint(clap::ValueHint::AnyPath),
+        )
+        .arg(
+            Arg::new(options::FROM)
+                .takes_value(true)
+                .value_hint(clap::ValueHint::AnyPath),
+        )
 }

src/uu/rm/src/rm.rs

@@ -227,6 +227,7 @@ pub fn uu_app<'a>() -> Command<'a> {
             .multiple_occurrences(true)
             .takes_value(true)
             .min_values(1)
+            .value_hint(clap::ValueHint::AnyPath)
         )
 }
 

src/uu/rmdir/src/rmdir.rs

@@ -197,6 +197,7 @@ pub fn uu_app<'a>() -> Command<'a> {
                 .takes_value(true)
                 .min_values(1)
                 .required(true)
-                .allow_invalid_utf8(true),
+                .allow_invalid_utf8(true)
+                .value_hint(clap::ValueHint::DirPath),
         )
 }

src/uu/runcon/src/runcon.rs

@@ -156,7 +156,8 @@ pub fn uu_app<'a>() -> Command<'a> {
         .arg(
             Arg::new("ARG")
                 .multiple_occurrences(true)
-                .allow_invalid_utf8(true),
+                .allow_invalid_utf8(true)
+                .value_hint(clap::ValueHint::CommandName),
         )
         // Once "ARG" is parsed, everything after that belongs to it.
         //

src/uu/shred/src/shred.rs

@@ -374,7 +374,8 @@ pub fn uu_app<'a>() -> Command<'a> {
         .arg(
             Arg::new(options::FILE)
                 .hide(true)
-                .multiple_occurrences(true),
+                .multiple_occurrences(true)
+                .value_hint(clap::ValueHint::FilePath),
         )
 }
 

src/uu/shuf/src/shuf.rs

@@ -158,14 +158,16 @@ pub fn uu_app<'a>() -> Command<'a> {
                 .long(options::OUTPUT)
                 .takes_value(true)
                 .value_name("FILE")
-                .help("write result to FILE instead of standard output"),
+                .help("write result to FILE instead of standard output")
+                .value_hint(clap::ValueHint::FilePath),
         )
         .arg(
             Arg::new(options::RANDOM_SOURCE)
                 .long(options::RANDOM_SOURCE)
                 .takes_value(true)
                 .value_name("FILE")
-                .help("get random bytes from FILE"),
+                .help("get random bytes from FILE")
+                .value_hint(clap::ValueHint::FilePath),
         )
         .arg(
             Arg::new(options::REPEAT)
@@ -179,7 +181,11 @@ pub fn uu_app<'a>() -> Command<'a> {
                 .long(options::ZERO_TERMINATED)
                 .help("line delimiter is NUL, not newline"),
         )
-        .arg(Arg::new(options::FILE).takes_value(true))
+        .arg(
+            Arg::new(options::FILE)
+                .takes_value(true)
+                .value_hint(clap::ValueHint::FilePath),
+        )
 }
 
 fn read_input_file(filename: &str) -> UResult<Vec<u8>> {

src/uu/sort/src/sort.rs

@@ -1397,7 +1397,8 @@ pub fn uu_app<'a>() -> Command<'a> {
                 .long(options::OUTPUT)
                 .help("write output to FILENAME instead of stdout")
                 .takes_value(true)
-                .value_name("FILENAME"),
+                .value_name("FILENAME")
+                .value_hint(clap::ValueHint::FilePath),
         )
         .arg(
             Arg::new(options::REVERSE)
@@ -1461,13 +1462,15 @@ pub fn uu_app<'a>() -> Command<'a> {
                 .long(options::TMP_DIR)
                 .help("use DIR for temporaries, not $TMPDIR or /tmp")
                 .takes_value(true)
-                .value_name("DIR"),
+                .value_name("DIR")
+                .value_hint(clap::ValueHint::DirPath),
         )
         .arg(
             Arg::new(options::COMPRESS_PROG)
                 .long(options::COMPRESS_PROG)
                 .help("compress temporary files with PROG, decompress with PROG -d; PROG has to take input from stdin and output to stdout")
-                .value_name("PROG"),
+                .value_name("PROG")
+                .value_hint(clap::ValueHint::CommandName),
         )
         .arg(
             Arg::new(options::BATCH_SIZE)
@@ -1482,7 +1485,8 @@ pub fn uu_app<'a>() -> Command<'a> {
                 .takes_value(true)
                 .value_name("NUL_FILES")
                 .multiple_occurrences(true)
-                .allow_invalid_utf8(true),
+                .allow_invalid_utf8(true)
+                .value_hint(clap::ValueHint::FilePath),
         )
         .arg(
             Arg::new(options::DEBUG)
@@ -1493,7 +1497,8 @@ pub fn uu_app<'a>() -> Command<'a> {
             Arg::new(options::FILES)
                 .multiple_occurrences(true)
                 .takes_value(true)
-                .allow_invalid_utf8(true),
+                .allow_invalid_utf8(true)
+                .value_hint(clap::ValueHint::FilePath),
         )
 }
 

src/uu/split/src/split.rs

@@ -111,9 +111,11 @@ pub fn uu_app<'a>() -> Command<'a> {
             Arg::new(OPT_FILTER)
                 .long(OPT_FILTER)
                 .takes_value(true)
+                .value_name("COMMAND")
+                .value_hint(clap::ValueHint::CommandName)
                 .help(
-                "write to shell COMMAND file name is $FILE (Currently not implemented for Windows)",
+                    "write to shell COMMAND; file name is $FILE (Currently not implemented for Windows)",
-            ),
+                ),
         )
         .arg(
             Arg::new(OPT_ELIDE_EMPTY_FILES)
@@ -162,7 +164,8 @@ pub fn uu_app<'a>() -> Command<'a> {
             Arg::new(ARG_INPUT)
                 .takes_value(true)
                 .default_value("-")
-                .index(1),
+                .index(1)
+                .value_hint(clap::ValueHint::FilePath),
         )
         .arg(
             Arg::new(ARG_PREFIX)

src/uu/stat/src/stat.rs

@@ -19,7 +19,9 @@ use uucore::{entries, format_usage};
 use clap::{crate_version, Arg, ArgMatches, Command};
 use std::borrow::Cow;
 use std::convert::AsRef;
+use std::ffi::{OsStr, OsString};
 use std::os::unix::fs::{FileTypeExt, MetadataExt};
+use std::os::unix::prelude::OsStrExt;
 use std::path::Path;
 use std::{cmp, fs, iter};
 
@@ -221,7 +223,7 @@ pub struct Stater {
     follow: bool,
     show_fs: bool,
     from_user: bool,
-    files: Vec<String>,
+    files: Vec<OsString>,
     mount_list: Option<Vec<String>>,
     default_tokens: Vec<Token>,
     default_dev_tokens: Vec<Token>,
@@ -471,24 +473,10 @@ impl Stater {
     }
 
     fn new(matches: &ArgMatches) -> UResult<Self> {
-        let mut files: Vec<String> = matches
+        let files = matches
-            .values_of(ARG_FILES)
+            .values_of_os(ARG_FILES)
-            .map(|v| v.map(ToString::to_string).collect())
+            .map(|v| v.map(OsString::from).collect())
             .unwrap_or_default();
-        #[cfg(unix)]
-        if files.contains(&String::from("-")) {
-            let redirected_path = Path::new("/dev/stdin")
-                .canonicalize()
-                .expect("unable to canonicalize /dev/stdin")
-                .into_os_string()
-                .into_string()
-                .unwrap();
-            for file in &mut files {
-                if file == "-" {
-                    *file = redirected_path.clone();
-                }
-            }
-        }
         let format_str = if matches.is_present(options::PRINTF) {
             matches
                 .value_of(options::PRINTF)
@@ -550,19 +538,37 @@ impl Stater {
     }
 
     fn exec(&self) -> i32 {
+        let mut stdin_is_fifo = false;
+        if cfg!(unix) {
+            if let Ok(md) = fs::metadata("/dev/stdin") {
+                stdin_is_fifo = md.file_type().is_fifo();
+            }
+        }
+
         let mut ret = 0;
         for f in &self.files {
-            ret |= self.do_stat(f.as_str());
+            ret |= self.do_stat(f, stdin_is_fifo);
         }
         ret
     }
 
-    fn do_stat(&self, file: &str) -> i32 {
+    fn do_stat(&self, file: &OsStr, stdin_is_fifo: bool) -> i32 {
-        if !self.show_fs {
+        let display_name = file.to_string_lossy();
-            let result = if self.follow {
+        let file: OsString = if cfg!(unix) && display_name.eq("-") {
-                fs::metadata(file)
+            if let Ok(p) = Path::new("/dev/stdin").canonicalize() {
+                p.into_os_string()
             } else {
-                fs::symlink_metadata(file)
+                OsString::from("/dev/stdin")
+            }
+        } else {
+            OsString::from(file)
+        };
+
+        if !self.show_fs {
+            let result = if self.follow || stdin_is_fifo && display_name.eq("-") {
+                fs::metadata(&file)
+            } else {
+                fs::symlink_metadata(&file)
             };
             match result {
                 Ok(meta) => {
@@ -658,28 +664,32 @@ impl Stater {
 
                                     // mount point
                                     'm' => {
-                                        arg = self.find_mount_point(file).unwrap();
+                                        arg = self.find_mount_point(&file).unwrap();
                                         output_type = OutputType::Str;
                                     }
 
                                     // file name
                                     'n' => {
-                                        arg = file.to_owned();
+                                        arg = display_name.to_string();
                                         output_type = OutputType::Str;
                                     }
                                     // quoted file name with dereference if symbolic link
                                     'N' => {
                                         if file_type.is_symlink() {
-                                            let dst = match fs::read_link(file) {
+                                            let dst = match fs::read_link(&file) {
                                                 Ok(path) => path,
                                                 Err(e) => {
                                                     println!("{}", e);
                                                     return 1;
                                                 }
                                             };
-                                            arg = format!("{} -> {}", file.quote(), dst.quote());
+                                            arg = format!(
+                                                "{} -> {}",
+                                                display_name.quote(),
+                                                dst.quote()
+                                            );
                                         } else {
-                                            arg = file.to_string();
+                                            arg = display_name.to_string();
                                         }
                                         output_type = OutputType::Str;
                                     }
@@ -771,12 +781,16 @@ impl Stater {
                     }
                 }
                 Err(e) => {
-                    show_error!("cannot stat {}: {}", file.quote(), e);
+                    show_error!("cannot stat {}: {}", display_name.quote(), e);
                     return 1;
                 }
             }
         } else {
-            match statfs(file) {
+            #[cfg(unix)]
+            let p = file.as_bytes();
+            #[cfg(not(unix))]
+            let p = file.into_string().unwrap();
+            match statfs(p) {
                 Ok(meta) => {
                     let tokens = &self.default_tokens;
 
@@ -829,7 +843,7 @@ impl Stater {
                                     }
                                     // file name
                                     'n' => {
-                                        arg = file.to_owned();
+                                        arg = display_name.to_string();
                                         output_type = OutputType::Str;
                                     }
                                     // block size (for faster transfers)
@@ -866,7 +880,7 @@ impl Stater {
                 Err(e) => {
                     show_error!(
                         "cannot read file system information for {}: {}",
-                        file.quote(),
+                        display_name.quote(),
                         e
                     );
                     return 1;
@@ -1028,6 +1042,8 @@ pub fn uu_app<'a>() -> Command<'a> {
             Arg::new(ARG_FILES)
                 .multiple_occurrences(true)
                 .takes_value(true)
-                .min_values(1),
+                .allow_invalid_utf8(true)
+                .min_values(1)
+                .value_hint(clap::ValueHint::FilePath),
         )
 }

src/uu/stdbuf/src/stdbuf.rs

@@ -232,6 +232,7 @@ pub fn uu_app<'a>() -> Command<'a> {
                 .multiple_occurrences(true)
                 .takes_value(true)
                 .hide(true)
-                .required(true),
+                .required(true)
+                .value_hint(clap::ValueHint::CommandName),
         )
 }

src/uu/sum/src/sum.rs

@@ -150,7 +150,8 @@ pub fn uu_app<'a>() -> Command<'a> {
         .arg(
             Arg::new(options::FILE)
                 .multiple_occurrences(true)
-                .hide(true),
+                .hide(true)
+                .value_hint(clap::ValueHint::FilePath),
         )
         .arg(
             Arg::new(options::BSD_COMPATIBLE)

src/uu/sync/src/sync.rs

@@ -217,7 +217,8 @@ pub fn uu_app<'a>() -> Command<'a> {
         .arg(
             Arg::new(ARG_FILES)
                 .multiple_occurrences(true)
-                .takes_value(true),
+                .takes_value(true)
+                .value_hint(clap::ValueHint::AnyPath),
         )
 }
 

src/uu/tac/src/tac.rs

@@ -91,7 +91,8 @@ pub fn uu_app<'a>() -> Command<'a> {
         .arg(
             Arg::new(options::FILE)
                 .hide(true)
-                .multiple_occurrences(true),
+                .multiple_occurrences(true)
+                .value_hint(clap::ValueHint::FilePath),
         )
 }
 

src/uu/tail/src/tail.rs

@@ -351,7 +351,8 @@ pub fn uu_app<'a>() -> Command<'a> {
             Arg::new(options::ARG_FILES)
                 .multiple_occurrences(true)
                 .takes_value(true)
-                .min_values(1),
+                .min_values(1)
+                .value_hint(clap::ValueHint::FilePath),
         )
 }
 

src/uu/tee/src/tee.rs

@@ -74,7 +74,11 @@ pub fn uu_app<'a>() -> Command<'a> {
                 .short('i')
                 .help("ignore interrupt signals (ignored on non-Unix platforms)"),
         )
-        .arg(Arg::new(options::FILE).multiple_occurrences(true))
+        .arg(
+            Arg::new(options::FILE)
+                .multiple_occurrences(true)
+                .value_hint(clap::ValueHint::FilePath),
+        )
 }
 
 #[cfg(unix)]

src/uu/timeout/src/timeout.rs

@@ -170,6 +170,7 @@ pub fn uu_app<'a>() -> Command<'a> {
                 .index(2)
                 .required(true)
                 .multiple_occurrences(true)
+                .value_hint(clap::ValueHint::CommandName)
         )
         .trailing_var_arg(true)
         .infer_long_args(true)

src/uu/touch/src/touch.rs

@@ -219,7 +219,8 @@ pub fn uu_app<'a>() -> Command<'a> {
                 .long(options::sources::REFERENCE)
                 .help("use this file's times instead of the current time")
                 .value_name("FILE")
-                .allow_invalid_utf8(true),
+                .allow_invalid_utf8(true)
+                .value_hint(clap::ValueHint::AnyPath),
         )
         .arg(
             Arg::new(options::TIME)
@@ -238,7 +239,8 @@ pub fn uu_app<'a>() -> Command<'a> {
                 .multiple_occurrences(true)
                 .takes_value(true)
                 .min_values(1)
-                .allow_invalid_utf8(true),
+                .allow_invalid_utf8(true)
+                .value_hint(clap::ValueHint::AnyPath),
         )
         .group(ArgGroup::new(options::SOURCES).args(&[
             options::sources::CURRENT,

src/uu/tr/src/tr.rs

@@ -143,7 +143,6 @@ pub fn uu_app<'a>() -> Command<'a> {
         .about(ABOUT)
         .override_usage(format_usage(USAGE))
         .infer_long_args(true)
-        .infer_long_args(true)
         .arg(
             Arg::new(options::COMPLEMENT)
                 .visible_short_alias('C')

src/uu/truncate/src/truncate.rs

@@ -162,6 +162,7 @@ pub fn uu_app<'a>() -> Command<'a> {
             .required_unless_present(options::SIZE)
             .help("base the size of each file on the size of RFILE")
             .value_name("RFILE")
+            .value_hint(clap::ValueHint::FilePath)
         )
         .arg(
             Arg::new(options::SIZE)
@@ -176,7 +177,8 @@ pub fn uu_app<'a>() -> Command<'a> {
              .multiple_occurrences(true)
              .takes_value(true)
              .required(true)
-             .min_values(1))
+             .min_values(1)
+             .value_hint(clap::ValueHint::FilePath))
 }
 
 /// Truncate the named file to the specified size.

src/uu/tsort/src/tsort.rs

@@ -99,7 +99,12 @@ pub fn uu_app<'a>() -> Command<'a> {
         .override_usage(format_usage(USAGE))
         .about(SUMMARY)
         .infer_long_args(true)
-        .arg(Arg::new(options::FILE).default_value("-").hide(true))
+        .arg(
+            Arg::new(options::FILE)
+                .default_value("-")
+                .hide(true)
+                .value_hint(clap::ValueHint::FilePath),
+        )
 }
 
 // We use String as a representation of node here

src/uu/unexpand/src/unexpand.rs

@@ -109,7 +109,12 @@ pub fn uu_app<'a>() -> Command<'a> {
         .override_usage(format_usage(USAGE))
         .about(SUMMARY)
         .infer_long_args(true)
-        .arg(Arg::new(options::FILE).hide(true).multiple_occurrences(true))
+        .arg(
+            Arg::new(options::FILE)
+                .hide(true)
+                .multiple_occurrences(true)
+                .value_hint(clap::ValueHint::FilePath)
+        )
         .arg(
             Arg::new(options::ALL)
                 .short('a')

src/uu/uniq/src/uniq.rs

@@ -392,7 +392,8 @@ pub fn uu_app<'a>() -> Command<'a> {
             Arg::new(ARG_FILES)
                 .multiple_occurrences(true)
                 .takes_value(true)
-                .max_values(2),
+                .max_values(2)
+                .value_hint(clap::ValueHint::FilePath),
         )
 }
 

src/uu/unlink/src/unlink.rs

@@ -36,6 +36,7 @@ pub fn uu_app<'a>() -> Command<'a> {
             Arg::new(OPT_PATH)
                 .required(true)
                 .hide(true)
-                .allow_invalid_utf8(true),
+                .allow_invalid_utf8(true)
+                .value_hint(clap::ValueHint::AnyPath),
         )
 }

src/uu/users/src/users.rs

@@ -64,5 +64,10 @@ pub fn uu_app<'a>() -> Command<'a> {
         .about(ABOUT)
         .override_usage(format_usage(USAGE))
         .infer_long_args(true)
-        .arg(Arg::new(ARG_FILES).takes_value(true).max_values(1))
+        .arg(
+            Arg::new(ARG_FILES)
+                .takes_value(true)
+                .max_values(1)
+                .value_hint(clap::ValueHint::FilePath),
+        )
 }

src/uu/wc/src/wc.rs

@@ -210,7 +210,8 @@ pub fn uu_app<'a>() -> Command<'a> {
                     "read input from the files specified by
     NUL-terminated names in file F;
     If F is - then read names from standard input",
-                ),
+                )
+                .value_hint(clap::ValueHint::FilePath),
         )
         .arg(
             Arg::new(options::LINES)
@@ -234,7 +235,8 @@ pub fn uu_app<'a>() -> Command<'a> {
             Arg::new(ARG_FILES)
                 .multiple_occurrences(true)
                 .takes_value(true)
-                .allow_invalid_utf8(true),
+                .allow_invalid_utf8(true)
+                .value_hint(clap::ValueHint::FilePath),
         )
 }
 

src/uu/who/src/who.rs

@@ -250,7 +250,8 @@ pub fn uu_app<'a>() -> Command<'a> {
             Arg::new(options::FILE)
                 .takes_value(true)
                 .min_values(1)
-                .max_values(2),
+                .max_values(2)
+                .value_hint(clap::ValueHint::FilePath),
         )
 }
 

src/uucore/src/lib/features/fsext.rs

@@ -85,6 +85,7 @@ use std::ffi::CString;
 use std::io::Error as IOError;
 #[cfg(unix)]
 use std::mem;
+#[cfg(not(unix))]
 use std::path::Path;
 use std::time::UNIX_EPOCH;
 
@@ -709,9 +710,9 @@ impl FsMeta for StatFs {
 }
 
 #[cfg(unix)]
-pub fn statfs<P: AsRef<Path>>(path: P) -> Result<StatFs, String>
+pub fn statfs<P>(path: P) -> Result<StatFs, String>
 where
-    Vec<u8>: From<P>,
+    P: Into<Vec<u8>>,
 {
     match CString::new(path) {
         Ok(p) => {

src/uucore/src/lib/features/perms.rs

@@ -92,22 +92,25 @@ pub fn wrap_chown<P: AsRef<Path>>(
                 );
                 if level == VerbosityLevel::Verbose {
                     out = if verbosity.groups_only {
+                        let gid = meta.gid();
                         format!(
                             "{}\nfailed to change group of {} from {} to {}",
                             out,
                             path.quote(),
-                            entries::gid2grp(meta.gid()).unwrap(),
+                            entries::gid2grp(gid).unwrap_or_else(|_| gid.to_string()),
-                            entries::gid2grp(dest_gid).unwrap()
+                            entries::gid2grp(dest_gid).unwrap_or_else(|_| dest_gid.to_string())
                         )
                     } else {
+                        let uid = meta.uid();
+                        let gid = meta.gid();
                         format!(
                             "{}\nfailed to change ownership of {} from {}:{} to {}:{}",
                             out,
                             path.quote(),
-                            entries::uid2usr(meta.uid()).unwrap(),
+                            entries::uid2usr(uid).unwrap_or_else(|_| uid.to_string()),
-                            entries::gid2grp(meta.gid()).unwrap(),
+                            entries::gid2grp(gid).unwrap_or_else(|_| gid.to_string()),
-                            entries::uid2usr(dest_uid).unwrap(),
+                            entries::uid2usr(dest_uid).unwrap_or_else(|_| dest_uid.to_string()),
-                            entries::gid2grp(dest_gid).unwrap()
+                            entries::gid2grp(dest_gid).unwrap_or_else(|_| dest_gid.to_string())
                         )
                     };
                 };
@@ -119,21 +122,24 @@ pub fn wrap_chown<P: AsRef<Path>>(
         if changed {
             match verbosity.level {
                 VerbosityLevel::Changes | VerbosityLevel::Verbose => {
+                    let gid = meta.gid();
                     out = if verbosity.groups_only {
                         format!(
                             "changed group of {} from {} to {}",
                             path.quote(),
-                            entries::gid2grp(meta.gid()).unwrap(),
+                            entries::gid2grp(gid).unwrap_or_else(|_| gid.to_string()),
-                            entries::gid2grp(dest_gid).unwrap()
+                            entries::gid2grp(dest_gid).unwrap_or_else(|_| dest_gid.to_string())
                         )
                     } else {
+                        let gid = meta.gid();
+                        let uid = meta.uid();
                         format!(
                             "changed ownership of {} from {}:{} to {}:{}",
                             path.quote(),
-                            entries::uid2usr(meta.uid()).unwrap(),
+                            entries::uid2usr(uid).unwrap_or_else(|_| uid.to_string()),
-                            entries::gid2grp(meta.gid()).unwrap(),
+                            entries::gid2grp(gid).unwrap_or_else(|_| gid.to_string()),
-                            entries::uid2usr(dest_uid).unwrap(),
+                            entries::uid2usr(dest_uid).unwrap_or_else(|_| dest_uid.to_string()),
-                            entries::gid2grp(dest_gid).unwrap()
+                            entries::gid2grp(dest_gid).unwrap_or_else(|_| dest_gid.to_string())
                         )
                     };
                 }
@@ -150,8 +156,8 @@ pub fn wrap_chown<P: AsRef<Path>>(
                 format!(
                     "ownership of {} retained as {}:{}",
                     path.quote(),
-                    entries::uid2usr(dest_uid).unwrap(),
+                    entries::uid2usr(dest_uid).unwrap_or_else(|_| dest_uid.to_string()),
-                    entries::gid2grp(dest_gid).unwrap()
+                    entries::gid2grp(dest_gid).unwrap_or_else(|_| dest_gid.to_string())
                 )
             };
         }
@@ -456,6 +462,7 @@ pub fn chown_base<'a>(
     command = command.arg(
         Arg::new(options::ARG_FILES)
             .value_name(options::ARG_FILES)
+            .value_hint(clap::ValueHint::FilePath)
             .multiple_occurrences(true)
             .takes_value(true)
             .required(true)

tests/by-util/test_chown.rs

@@ -418,6 +418,29 @@ fn test_chown_only_user_id() {
         .stderr_contains(&"failed to change");
 }
 
+/// Test for setting the owner to a user ID for a user that does not exist.
+///
+/// For example:
+///
+///     $ touch f && chown 12345 f
+///
+/// succeeds with exit status 0 and outputs nothing. The owner of the
+/// file is set to 12345, even though no user with that ID exists.
+///
+/// This test must be run as root, because only the root user can
+/// transfer ownership of a file.
+#[test]
+fn test_chown_only_user_id_nonexistent_user() {
+    let ts = TestScenario::new(util_name!());
+    let at = ts.fixtures.clone();
+    at.touch("f");
+    if let Ok(result) = run_ucmd_as_root(&ts, &["12345", "f"]) {
+        result.success().no_stdout().no_stderr();
+    } else {
+        print!("Test skipped; requires root user");
+    }
+}
+
 #[test]
 // FixME: stderr = chown: ownership of 'test_chown_file1' retained as cuuser:wheel
 #[cfg(not(target_os = "freebsd"))]
@@ -461,6 +484,29 @@ fn test_chown_only_group_id() {
         .stderr_contains(&"failed to change");
 }
 
+/// Test for setting the group to a group ID for a group that does not exist.
+///
+/// For example:
+///
+///     $ touch f && chown :12345 f
+///
+/// succeeds with exit status 0 and outputs nothing. The group of the
+/// file is set to 12345, even though no group with that ID exists.
+///
+/// This test must be run as root, because only the root user can
+/// transfer ownership of a file.
+#[test]
+fn test_chown_only_group_id_nonexistent_group() {
+    let ts = TestScenario::new(util_name!());
+    let at = ts.fixtures.clone();
+    at.touch("f");
+    if let Ok(result) = run_ucmd_as_root(&ts, &[":12345", "f"]) {
+        result.success().no_stdout().no_stderr();
+    } else {
+        print!("Test skipped; requires root user");
+    }
+}
+
 #[test]
 fn test_chown_owner_group_id() {
     // test chown 1111:1111 file.txt

tests/by-util/test_df.rs

@@ -73,7 +73,7 @@ fn test_df_output() {
             "Filesystem",
             "Size",
             "Used",
-            "Available",
+            "Avail",
             "Capacity",
             "Use%",
             "Mounted",
@@ -84,7 +84,7 @@ fn test_df_output() {
             "Filesystem",
             "Size",
             "Used",
-            "Available",
+            "Avail",
             "Use%",
             "Mounted",
             "on",
@@ -107,7 +107,7 @@ fn test_df_output_overridden() {
             "Filesystem",
             "Size",
             "Used",
-            "Available",
+            "Avail",
             "Capacity",
             "Use%",
             "Mounted",
@@ -118,7 +118,7 @@ fn test_df_output_overridden() {
             "Filesystem",
             "Size",
             "Used",
-            "Available",
+            "Avail",
             "Use%",
             "Mounted",
             "on",
@@ -134,6 +134,46 @@ fn test_df_output_overridden() {
     assert_eq!(actual, expected);
 }
 
+#[test]
+fn test_default_headers() {
+    let expected = if cfg!(target_os = "macos") {
+        vec![
+            "Filesystem",
+            "1K-blocks",
+            "Used",
+            "Available",
+            "Capacity",
+            "Use%",
+            "Mounted",
+            "on",
+        ]
+    } else {
+        vec![
+            "Filesystem",
+            "1K-blocks",
+            "Used",
+            "Available",
+            "Use%",
+            "Mounted",
+            "on",
+        ]
+    };
+    let output = new_ucmd!().succeeds().stdout_move_str();
+    let actual = output.lines().take(1).collect::<Vec<&str>>()[0];
+    let actual = actual.split_whitespace().collect::<Vec<_>>();
+    assert_eq!(actual, expected);
+}
+
+#[test]
+fn test_precedence_of_human_readable_header_over_output_header() {
+    let output = new_ucmd!()
+        .args(&["-H", "--output=size"])
+        .succeeds()
+        .stdout_move_str();
+    let header = output.lines().next().unwrap().to_string();
+    assert_eq!(header.trim(), "Size");
+}
+
 #[test]
 fn test_total_option_with_single_dash() {
     // These should fail because `-total` should have two dashes,
@@ -395,6 +435,30 @@ fn test_default_block_size() {
     assert_eq!(header, "512B-blocks");
 }
 
+#[test]
+fn test_default_block_size_in_posix_portability_mode() {
+    fn get_header(s: &str) -> String {
+        s.lines()
+            .next()
+            .unwrap()
+            .to_string()
+            .split_whitespace()
+            .nth(1)
+            .unwrap()
+            .to_string()
+    }
+
+    let output = new_ucmd!().arg("-P").succeeds().stdout_move_str();
+    assert_eq!(get_header(&output), "1024-blocks");
+
+    let output = new_ucmd!()
+        .arg("-P")
+        .env("POSIXLY_CORRECT", "1")
+        .succeeds()
+        .stdout_move_str();
+    assert_eq!(get_header(&output), "512-blocks");
+}
+
 #[test]
 fn test_block_size_1024() {
     fn get_header(block_size: u64) -> String {
@@ -443,6 +507,31 @@ fn test_block_size_with_suffix() {
     assert_eq!(get_header("1GB"), "1GB-blocks");
 }
 
+#[test]
+fn test_block_size_in_posix_portability_mode() {
+    fn get_header(block_size: &str) -> String {
+        let output = new_ucmd!()
+            .args(&["-P", "-B", block_size])
+            .succeeds()
+            .stdout_move_str();
+        output
+            .lines()
+            .next()
+            .unwrap()
+            .to_string()
+            .split_whitespace()
+            .nth(1)
+            .unwrap()
+            .to_string()
+    }
+
+    assert_eq!(get_header("1024"), "1024-blocks");
+    assert_eq!(get_header("1K"), "1024-blocks");
+    assert_eq!(get_header("1KB"), "1000-blocks");
+    assert_eq!(get_header("1M"), "1048576-blocks");
+    assert_eq!(get_header("1MB"), "1000000-blocks");
+}
+
 #[test]
 fn test_too_large_block_size() {
     fn run_command(size: &str) {
@@ -465,6 +554,16 @@ fn test_invalid_block_size() {
         .arg("--block-size=x")
         .fails()
         .stderr_contains("invalid --block-size argument 'x'");
+
+    new_ucmd!()
+        .arg("--block-size=0")
+        .fails()
+        .stderr_contains("invalid --block-size argument '0'");
+
+    new_ucmd!()
+        .arg("--block-size=0K")
+        .fails()
+        .stderr_contains("invalid --block-size argument '0K'");
 }
 
 #[test]

tests/by-util/test_mktemp.rs

@@ -2,6 +2,8 @@
 
 use crate::common::util::*;
 
+use uucore::display::Quotable;
+
 use std::path::PathBuf;
 use tempfile::tempdir;
 
@@ -497,3 +499,15 @@ fn test_directory_permissions() {
     assert!(metadata.is_dir());
     assert_eq!(metadata.permissions().mode(), 0o40700);
 }
+
+/// Test that a template with a path separator is invalid.
+#[test]
+fn test_template_path_separator() {
+    new_ucmd!()
+        .args(&["-t", "a/bXXX"])
+        .fails()
+        .stderr_only(format!(
+            "mktemp: invalid template, {}, contains directory separator\n",
+            "a/bXXX".quote()
+        ));
+}

tests/by-util/test_stat.rs

@@ -346,14 +346,25 @@ fn test_printf() {
     ts.ucmd().args(&args).succeeds().stdout_is(expected_stdout);
 }
 
-#[cfg(unix)]
 #[test]
-#[cfg(disable_until_fixed)]
+#[cfg(unix)]
+fn test_pipe_fifo() {
+    let (at, mut ucmd) = at_and_ucmd!();
+    at.mkfifo("FIFO");
+    ucmd.arg("FIFO")
+        .run()
+        .no_stderr()
+        .stdout_contains("fifo")
+        .stdout_contains("File: FIFO")
+        .succeeded();
+}
+
+#[test]
+#[cfg(all(unix, not(target_os = "android")))]
 fn test_stdin_pipe_fifo1() {
     // $ echo | stat -
     // File: -
     // Size: 0               Blocks: 0          IO Block: 4096   fifo
-    // use std::process::{Command, Stdio};
     new_ucmd!()
         .arg("-")
         .set_stdin(std::process::Stdio::piped())
@@ -362,17 +373,25 @@ fn test_stdin_pipe_fifo1() {
         .stdout_contains("fifo")
         .stdout_contains("File: -")
         .succeeded();
+    new_ucmd!()
+        .args(&["-L", "-"])
+        .set_stdin(std::process::Stdio::piped())
+        .run()
+        .no_stderr()
+        .stdout_contains("fifo")
+        .stdout_contains("File: -")
+        .succeeded();
 }
 
-#[cfg(unix)]
 #[test]
-#[cfg(disable_until_fixed)]
+#[cfg(all(unix, not(target_os = "android")))]
 fn test_stdin_pipe_fifo2() {
     // $ stat -
     // File: -
     // Size: 0               Blocks: 0          IO Block: 1024   character special file
     new_ucmd!()
         .arg("-")
+        .set_stdin(std::process::Stdio::null())
         .run()
         .no_stderr()
         .stdout_contains("character special file")
@@ -380,20 +399,18 @@ fn test_stdin_pipe_fifo2() {
         .succeeded();
 }
 
-#[cfg(unix)]
 #[test]
-#[cfg(disable_until_fixed)]
+#[cfg(all(unix, not(any(target_os = "android", target_os = "macos"))))]
 fn test_stdin_redirect() {
     // $ touch f && stat - < f
     // File: -
     // Size: 0               Blocks: 0          IO Block: 4096   regular empty file
-
     let ts = TestScenario::new(util_name!());
     let at = &ts.fixtures;
     at.touch("f");
-    new_ucmd!()
+    ts.ucmd()
         .arg("-")
-        .set_stdin(std::fs::File::open("f").unwrap())
+        .set_stdin(std::fs::File::open(at.plus("f")).unwrap())
         .run()
         .no_stderr()
         .stdout_contains("regular empty file")