diff --git a/src/uu/tr/src/tr.rs b/src/uu/tr/src/tr.rs index 6c1c0746a..09c4304a5 100644 --- a/src/uu/tr/src/tr.rs +++ b/src/uu/tr/src/tr.rs @@ -278,8 +278,58 @@ pub fn uumain(args: impl uucore::Args) -> i32 { translate_input(&mut locked_stdin, &mut buffered_stdout, op); } } else if squeeze_flag { - let op = SqueezeOperation::new(set1, complement_flag); - translate_input(&mut locked_stdin, &mut buffered_stdout, op); + if sets.len() < 2 { + 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(); + } + } } else { let mut set2 = ExpandSet::new(sets[1].as_ref()); let op = TranslateOperation::new(set1, &mut set2, truncate_flag); diff --git a/tests/by-util/test_tr.rs b/tests/by-util/test_tr.rs index 630c305c6..5d044a187 100644 --- a/tests/by-util/test_tr.rs +++ b/tests/by-util/test_tr.rs @@ -63,6 +63,24 @@ fn test_squeeze_complement() { .stdout_is("aaBcDcc"); } +#[test] +fn test_translate_and_squeeze() { + new_ucmd!() + .args(&["-s", "x", "y"]) + .pipe_in("xx") + .run() + .stdout_is("y"); +} + +#[test] +fn test_translate_and_squeeze_multiple_lines() { + new_ucmd!() + .args(&["-s", "x", "y"]) + .pipe_in("xxaax\nxaaxx") + .run() + .stdout_is("yaay\nyaay"); +} + #[test] fn test_delete_and_squeeze() { new_ucmd!()