diff --git a/src/uu/tr/src/tr.rs b/src/uu/tr/src/tr.rs index 09c4304a5..e04737a45 100644 --- a/src/uu/tr/src/tr.rs +++ b/src/uu/tr/src/tr.rs @@ -151,6 +151,35 @@ impl SymbolTranslator for TranslateOperation { } } +struct TranslateAndSqueezeOperation { + translate: TranslateOperation, + squeeze: SqueezeOperation, +} + +impl TranslateAndSqueezeOperation { + fn new( + set1: ExpandSet, + set2: &mut ExpandSet, + set2_: ExpandSet, + truncate: bool, + complement: bool, + ) -> TranslateAndSqueezeOperation { + TranslateAndSqueezeOperation { + translate: TranslateOperation::new(set1, set2, truncate), + squeeze: SqueezeOperation::new(set2_, complement), + } + } +} + +impl SymbolTranslator for TranslateAndSqueezeOperation { + fn translate(&self, c: char, prev_c: char) -> Option { + // `unwrap()` will never panic because `Translate.translate()` + // always returns `Some`. + self.squeeze + .translate(self.translate.translate(c, 0 as char).unwrap(), prev_c) + } +} + fn translate_input( input: &mut dyn BufRead, output: &mut dyn Write, @@ -168,8 +197,11 @@ fn translate_input( // isolation to make borrow checker happy let filtered = buf.chars().filter_map(|c| { let res = translator.translate(c, prev_c); + // Set `prev_c` to the post-translate character. This + // allows the squeeze operation to correctly function + // after the translate operation. if res.is_some() { - prev_c = c; + prev_c = res.unwrap(); } res }); @@ -282,53 +314,16 @@ pub fn uumain(args: impl uucore::Args) -> i32 { let op = SqueezeOperation::new(set1, complement_flag); translate_input(&mut locked_stdin, &mut buffered_stdout, op); } else { - // Define a closure that computes the translation using a hash map. - // - // The `unwrap()` should never panic because the - // `TranslateOperation.translate()` method always returns - // `Some`. let mut set2 = ExpandSet::new(sets[1].as_ref()); - let translator = TranslateOperation::new(set1, &mut set2, truncate_flag); - let translate = |c| translator.translate(c, 0 as char).unwrap(); - - // Prepare some variables to be used for the closure that - // computes the squeeze operation. - // - // The `squeeze()` closure needs to be defined anew for - // each line of input, but these variables do not change - // while reading the input so they can be defined before - // the `while` loop. - let set2 = ExpandSet::new(sets[1].as_ref()); - let squeezer = SqueezeOperation::new(set2, complement_flag); - - // Prepare some memory to read each line of the input (`buf`) and to write - let mut buf = String::with_capacity(BUFFER_LEN + 4); - - // Loop over each line of stdin. - while let Ok(length) = locked_stdin.read_line(&mut buf) { - if length == 0 { - break; - } - - // Define a closure that computes the squeeze operation. - // - // We keep track of the previously seen character on - // each call to `squeeze()`, but we need to reset the - // `prev_c` variable at the beginning of each line of - // the input. That's why we define the closure inside - // the `while` loop. - let mut prev_c = 0 as char; - let squeeze = |c| { - let result = squeezer.translate(c, prev_c); - prev_c = c; - result - }; - - // First translate, then squeeze each character of the input line. - let filtered: String = buf.chars().map(translate).filter_map(squeeze).collect(); - buf.clear(); - buffered_stdout.write_all(filtered.as_bytes()).unwrap(); - } + let set2_ = ExpandSet::new(sets[1].as_ref()); + let op = TranslateAndSqueezeOperation::new( + set1, + &mut set2, + set2_, + complement_flag, + truncate_flag, + ); + translate_input(&mut locked_stdin, &mut buffered_stdout, op); } } else { let mut set2 = ExpandSet::new(sets[1].as_ref());