From dad7761be96e18bb66d3ff50642fab36fb242955 Mon Sep 17 00:00:00 2001
From: electricboogie <32370782+electricboogie@users.noreply.github.com>
Date: Sun, 18 Apr 2021 13:43:41 -0500
Subject: [PATCH] Add test

---
 src/uu/sort/src/ext_sorter.rs | 72 +++++++++++++++++++++++++++++++++++
 src/uu/sort/src/sort.rs       |  6 +--
 tests/by-util/test_sort.rs    | 25 +++++-------
 3 files changed, 83 insertions(+), 20 deletions(-)

diff --git a/src/uu/sort/src/ext_sorter.rs b/src/uu/sort/src/ext_sorter.rs
index d607cbd3e..00fe9b401 100644
--- a/src/uu/sort/src/ext_sorter.rs
+++ b/src/uu/sort/src/ext_sorter.rs
@@ -74,6 +74,18 @@ impl ExternalSorter {
         self
     }
 
+    /// Sorts a given iterator, returning a new iterator with items
+    pub fn sort<T, I>(
+        &self,
+        iterator: I,
+    ) -> Result<SortedIterator<T, impl Fn(&T, &T) -> Ordering + Send + Sync>, Error>
+    where
+        T: Sortable + Ord,
+        I: Iterator<Item = T>,
+    {
+        self.sort_by(iterator, |a, b| a.cmp(b))
+    }
+    
     /// Sorts a given iterator with a comparator function, returning a new iterator with items
     pub fn sort_by<T, I, F>(&self, iterator: I, cmp: F) -> Result<SortedIterator<T, F>, Error>
     where
@@ -255,3 +267,63 @@ impl<T: Sortable, F: Fn(&T, &T) -> Ordering> Iterator for SortedIterator<T, F> {
         })
     }
 }
+
+#[cfg(test)]
+pub mod test {
+    use super::*;
+
+    use byteorder::{ReadBytesExt, WriteBytesExt};
+
+    #[test]
+    fn test_smaller_than_segment() {
+        let sorter = ExternalSorter::new();
+        let data: Vec<u32> = (0..100u32).collect();
+        let data_rev: Vec<u32> = data.iter().rev().cloned().collect();
+
+        let sorted_iter = sorter.sort(data_rev.into_iter()).unwrap();
+
+        // should not have used any segments (all in memory)
+        assert_eq!(sorted_iter.segments_file.len(), 0);
+        let sorted_data: Vec<u32> = sorted_iter.collect();
+
+        assert_eq!(data, sorted_data);
+    }
+
+    #[test]
+    fn test_multiple_segments() {
+        let sorter = ExternalSorter::new().with_segment_size(100);
+        let data: Vec<u32> = (0..1000u32).collect();
+
+        let data_rev: Vec<u32> = data.iter().rev().cloned().collect();
+        let sorted_iter = sorter.sort(data_rev.into_iter()).unwrap();
+        assert_eq!(sorted_iter.segments_file.len(), 10);
+
+        let sorted_data: Vec<u32> = sorted_iter.collect();
+        assert_eq!(data, sorted_data);
+    }
+
+    #[test]
+    fn test_parallel() {
+        let sorter = ExternalSorter::new()
+            .with_segment_size(100)
+            .with_parallel_sort();
+        let data: Vec<u32> = (0..1000u32).collect();
+
+        let data_rev: Vec<u32> = data.iter().rev().cloned().collect();
+        let sorted_iter = sorter.sort(data_rev.into_iter()).unwrap();
+        assert_eq!(sorted_iter.segments_file.len(), 10);
+
+        let sorted_data: Vec<u32> = sorted_iter.collect();
+        assert_eq!(data, sorted_data);
+    }
+
+    impl Sortable for u32 {
+        fn encode<W: Write>(&self, writer: &mut W) {
+            writer.write_u32::<byteorder::LittleEndian>(*self).unwrap();
+        }
+
+        fn decode<R: Read>(reader: &mut R) -> Option<u32> {
+            reader.read_u32::<byteorder::LittleEndian>().ok()
+        }
+    }
+}
diff --git a/src/uu/sort/src/sort.rs b/src/uu/sort/src/sort.rs
index fab712978..4854990e6 100644
--- a/src/uu/sort/src/sort.rs
+++ b/src/uu/sort/src/sort.rs
@@ -90,7 +90,7 @@ static NEGATIVE: char = '-';
 static POSITIVE: char = '+';
 
 static DEFAULT_TMPDIR: &str = r"/tmp";
-// 16GB buffer for Vec<Lines> before we dump to disk
+// 16GB buffer for Vec<Line> before we dump to disk
 static DEFAULT_BUF_SIZE: usize = 16000000000;
 
 #[derive(Eq, Ord, PartialEq, PartialOrd, Clone)]
@@ -890,11 +890,7 @@ pub fn uumain(args: impl uucore::Args) -> i32 {
                 .map(String::from)
                 .unwrap_or(format!("{}", DEFAULT_BUF_SIZE));
 
-            if human_numeric_convert(&input) < 128000 {
-                panic!("sort will not operate with less than 128K of memory.");
-            } else {
                 human_numeric_convert(&input)
-            }
         }
     }
 
diff --git a/tests/by-util/test_sort.rs b/tests/by-util/test_sort.rs
index a4a9a383c..0ca917a86 100644
--- a/tests/by-util/test_sort.rs
+++ b/tests/by-util/test_sort.rs
@@ -8,6 +8,16 @@ fn test_helper(file_name: &str, args: &str) {
         .stdout_is_fixture(format!("{}.expected", file_name));
 }
 
+#[test]
+fn test_larger_than_specified_segment() {
+    new_ucmd!()
+        .arg("-n")
+        .arg("-S 100")
+        .arg("numeric_unsorted_ints.txt")
+        .succeeds()
+        .stdout_is_fixture(format!("{}", "numeric_unsorted_ints.expected"));
+}
+
 #[test]
 fn test_months_whitespace() {
     test_helper("months-whitespace", "-M");
@@ -100,21 +110,6 @@ fn test_random_shuffle_two_runs_not_the_same() {
     assert_ne!(result, unexpected);
 }
 
-#[test]
-fn test_random_shuffle_contains_two_runs_not_the_same() {
-    // check to verify that two random shuffles are not equal; this has the
-    // potential to fail in the unlikely event that random order is the same
-    // as the starting order, or if both random sorts end up having the same order.
-    const FILE: &'static str = "default_unsorted_ints.expected";
-    let (at, _ucmd) = at_and_ucmd!();
-    let result = new_ucmd!().arg("-R").arg(FILE).run().stdout_move_str();
-    let expected = at.read(FILE);
-    let unexpected = new_ucmd!().arg("-R").arg(FILE).run().stdout_move_str();
-
-    assert_ne!(result, expected);
-    assert_ne!(result, unexpected);
-}
-
 #[test]
 fn test_numeric_floats_and_ints() {
     test_helper("numeric_floats_and_ints", "-n");