perf: Vendor textwrap parts we need

The immediate benefit is binary size but this also makes us more
flexible on the implementation, like allowing wrapping of `StyledStr`.

This removed 12 KiB from `.text`

This helps towards #1365 and probably #2037

Cargo.lock

@@ -113,7 +113,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "a0610544180c38b88101fecf2dd634b174a62eef6946f84dfc6a7127512b381c"
 dependencies = [
  "bitflags",
- "textwrap 0.11.0",
+ "textwrap",
  "unicode-width",
 ]
 
@@ -133,8 +133,7 @@ dependencies = [
  "static_assertions",
  "strsim",
  "termcolor",
- "terminal_size 0.2.1",
+ "terminal_size",
- "textwrap 0.15.0",
  "trybuild",
  "trycmd",
  "unic-emoji-char",
@@ -931,16 +930,6 @@ dependencies = [
  "winapi-util",
 ]
 
-[[package]]
-name = "terminal_size"
-version = "0.1.17"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "633c1a546cee861a1a6d0dc69ebeca693bf4296661ba7852b9d21d159e0506df"
-dependencies = [
- "libc",
- "winapi",
-]
-
 [[package]]
 name = "terminal_size"
 version = "0.2.1"
@@ -960,16 +949,6 @@ dependencies = [
  "unicode-width",
 ]
 
-[[package]]
-name = "textwrap"
-version = "0.15.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "b1141d4d61095b28419e22cb0bbf02755f5e54e0526f97f1e3d1d160e60885fb"
-dependencies = [
- "terminal_size 0.1.17",
- "unicode-width",
-]
-
 [[package]]
 name = "tinytemplate"
 version = "1.2.1"

Cargo.toml

@@ -71,9 +71,9 @@ suggestions = ["dep:strsim"]
 deprecated = ["clap_derive?/deprecated"] # Guided experience to prepare for next breaking release (at different stages of development, this may become default)
 derive = ["clap_derive"]
 cargo = [] # Disable if you're not using Cargo, enables Cargo-env-var-dependent macros
-wrap_help = ["dep:terminal_size", "textwrap/terminal_size"]
+wrap_help = ["dep:terminal_size"]
 env = [] # Use environment variables during arg parsing
-unicode = ["textwrap/unicode-width", "dep:unicode-width", "dep:unicase"]  # Support for unicode characters in arguments and help messages
+unicode = ["dep:unicode-width", "dep:unicase"]  # Support for unicode characters in arguments and help messages
 perf = [] # Optimize for runtime performance
 
 # In-work features
@@ -88,7 +88,6 @@ bench = false
 clap_derive = { path = "./clap_derive", version = "=4.0.0-alpha.0", optional = true }
 clap_lex = { path = "./clap_lex", version = "0.2.2" }
 bitflags = "1.2"
-textwrap = { version = "0.15.0", default-features = false, features = [] }
 unicase = { version = "2.6", optional = true }
 strsim = { version = "0.10",  optional = true }
 atty = { version = "0.2",  optional = true }

src/output/help.rs

@@ -10,6 +10,7 @@ use crate::builder::Str;
 use crate::builder::StyledStr;
 use crate::builder::{render_arg_val, Arg, Command};
 use crate::output::display_width;
+use crate::output::wrap;
 use crate::output::Usage;
 use crate::util::FlatSet;
 use crate::ArgAction;
@@ -355,7 +356,7 @@ impl<'cmd, 'writer> Help<'cmd, 'writer> {
             self.cmd.get_before_help()
         };
         if let Some(output) = before_help {
-            self.none(text_wrapper(
+            self.none(wrap(
                 &output.unwrap_none().replace("{n}", "\n"),
                 self.term_w,
             ));
@@ -374,7 +375,7 @@ impl<'cmd, 'writer> Help<'cmd, 'writer> {
         };
         if let Some(output) = after_help {
             self.none("\n\n");
-            self.none(text_wrapper(
+            self.none(wrap(
                 &output.unwrap_none().replace("{n}", "\n"),
                 self.term_w,
             ));
@@ -415,7 +416,7 @@ impl<'cmd, 'writer> Help<'cmd, 'writer> {
             // Determine how many newlines we need to insert
             let avail_chars = self.term_w - spaces;
             debug!("Help::help: Usable space...{}", avail_chars);
-            help = text_wrapper(&help.replace("{n}", "\n"), avail_chars);
+            help = wrap(&help.replace("{n}", "\n"), avail_chars);
         } else {
             debug!("No");
         }
@@ -498,7 +499,7 @@ impl<'cmd, 'writer> Help<'cmd, 'writer> {
                             usize::MAX
                         };
 
-                        let help = text_wrapper(help.unwrap_none(), avail_chars);
+                        let help = wrap(help.unwrap_none(), avail_chars);
                         let mut help = help.lines();
 
                         self.none(help.next().unwrap_or_default());
@@ -657,7 +658,7 @@ impl<'cmd, 'writer> Help<'cmd, 'writer> {
             if before_new_line {
                 self.none("\n");
             }
-            self.none(text_wrapper(output.unwrap_none(), self.term_w));
+            self.none(wrap(output.unwrap_none(), self.term_w));
             if after_new_line {
                 self.none("\n");
             }
@@ -669,7 +670,7 @@ impl<'cmd, 'writer> Help<'cmd, 'writer> {
             if before_new_line {
                 self.none("\n");
             }
-            self.none(text_wrapper(author, self.term_w));
+            self.none(wrap(author, self.term_w));
             if after_new_line {
                 self.none("\n");
             }
@@ -682,7 +683,7 @@ impl<'cmd, 'writer> Help<'cmd, 'writer> {
             .get_version()
             .or_else(|| self.cmd.get_long_version());
         if let Some(output) = version {
-            self.none(text_wrapper(output, self.term_w));
+            self.none(wrap(output, self.term_w));
         }
     }
 }
@@ -906,7 +907,7 @@ impl<'cmd, 'writer> Help<'cmd, 'writer> {
     fn write_display_name(&mut self) {
         debug!("Help::write_display_name");
 
-        let display_name = text_wrapper(
+        let display_name = wrap(
             &self
                 .cmd
                 .get_display_name()
@@ -926,10 +927,10 @@ impl<'cmd, 'writer> Help<'cmd, 'writer> {
                 // In case we're dealing with subcommands i.e. git mv is translated to git-mv
                 bn.replace(' ', "-")
             } else {
-                text_wrapper(&self.cmd.get_name().replace("{n}", "\n"), self.term_w)
+                wrap(&self.cmd.get_name().replace("{n}", "\n"), self.term_w)
             }
         } else {
-            text_wrapper(&self.cmd.get_name().replace("{n}", "\n"), self.term_w)
+            wrap(&self.cmd.get_name().replace("{n}", "\n"), self.term_w)
         };
         self.good(&bin_name);
     }
@@ -1071,16 +1072,6 @@ fn should_show_subcommand(subcommand: &Command) -> bool {
     !subcommand.is_hide_set()
 }
 
-fn text_wrapper(help: &str, width: usize) -> String {
-    let wrapper = textwrap::Options::new(width)
-        .break_words(false)
-        .word_splitter(textwrap::WordSplitter::NoHyphenation);
-    help.lines()
-        .map(|line| textwrap::fill(line, &wrapper))
-        .collect::<Vec<String>>()
-        .join("\n")
-}
-
 #[cfg(test)]
 mod test {
     use super::*;
@@ -1088,7 +1079,7 @@ mod test {
     #[test]
     fn wrap_help_last_word() {
         let help = String::from("foo bar baz");
-        assert_eq!(text_wrapper(&help, 5), "foo\nbar\nbaz");
+        assert_eq!(wrap(&help, 5), "foo\nbar\nbaz");
     }
 
     #[test]

src/output/mod.rs

@@ -6,4 +6,5 @@ pub(crate) mod fmt;
 
 pub(crate) use self::help::Help;
 pub(crate) use self::textwrap::core::display_width;
+pub(crate) use self::textwrap::wrap;
 pub(crate) use self::usage::Usage;

src/output/textwrap/mod.rs

@@ -1 +1,113 @@
+//! Fork of `textwrap` crate
+//!
+//! Benefits of forking:
+//! - Pull in only what we need rather than relying on the compiler to remove what we don't need
+//! - `LineWrapper` is able to incrementally wrap which will help with `StyledStr
+
 pub(crate) mod core;
+pub(crate) mod word_separators;
+pub(crate) mod wrap_algorithms;
+
+pub(crate) fn wrap(content: &str, hard_width: usize) -> String {
+    let mut wrapper = wrap_algorithms::LineWrapper::new(hard_width);
+    let mut total = Vec::new();
+    for line in content.split_inclusive('\n') {
+        wrapper.reset();
+        let line = word_separators::find_words_ascii_space(line).collect::<Vec<_>>();
+        total.extend(wrapper.wrap(line));
+    }
+    total.join("")
+}
+
+#[cfg(test)]
+mod test {
+    /// Compatibility shim to keep textwrap's tests
+    fn wrap(content: &str, hard_width: usize) -> Vec<String> {
+        super::wrap(content, hard_width)
+            .trim_end()
+            .split('\n')
+            .map(|s| s.to_owned())
+            .collect::<Vec<_>>()
+    }
+
+    #[test]
+    fn no_wrap() {
+        assert_eq!(wrap("foo", 10), vec!["foo"]);
+    }
+
+    #[test]
+    fn wrap_simple() {
+        assert_eq!(wrap("foo bar baz", 5), vec!["foo", "bar", "baz"]);
+    }
+
+    #[test]
+    fn to_be_or_not() {
+        assert_eq!(
+            wrap("To be, or not to be, that is the question.", 10),
+            vec!["To be, or", "not to be,", "that is", "the", "question."]
+        );
+    }
+
+    #[test]
+    fn multiple_words_on_first_line() {
+        assert_eq!(wrap("foo bar baz", 10), vec!["foo bar", "baz"]);
+    }
+
+    #[test]
+    fn long_word() {
+        assert_eq!(wrap("foo", 0), vec!["foo"]);
+    }
+
+    #[test]
+    fn long_words() {
+        assert_eq!(wrap("foo bar", 0), vec!["foo", "bar"]);
+    }
+
+    #[test]
+    fn max_width() {
+        assert_eq!(wrap("foo bar", usize::MAX), vec!["foo bar"]);
+
+        let text = "Hello there! This is some English text. \
+                    It should not be wrapped given the extents below.";
+        assert_eq!(wrap(text, usize::MAX), vec![text]);
+    }
+
+    #[test]
+    fn leading_whitespace() {
+        assert_eq!(wrap("  foo bar", 6), vec!["  foo", "bar"]);
+    }
+
+    #[test]
+    fn leading_whitespace_empty_first_line() {
+        // If there is no space for the first word, the first line
+        // will be empty. This is because the string is split into
+        // words like [" ", "foobar ", "baz"], which puts "foobar " on
+        // the second line. We never output trailing whitespace
+        assert_eq!(wrap(" foobar baz", 6), vec!["", "foobar", "baz"]);
+    }
+
+    #[test]
+    fn trailing_whitespace() {
+        // Whitespace is only significant inside a line. After a line
+        // gets too long and is broken, the first word starts in
+        // column zero and is not indented.
+        assert_eq!(wrap("foo     bar     baz  ", 5), vec!["foo", "bar", "baz"]);
+    }
+
+    #[test]
+    fn issue_99() {
+        // We did not reset the in_whitespace flag correctly and did
+        // not handle single-character words after a line break.
+        assert_eq!(
+            wrap("aaabbbccc x yyyzzzwww", 9),
+            vec!["aaabbbccc", "x", "yyyzzzwww"]
+        );
+    }
+
+    #[test]
+    fn issue_129() {
+        // The dash is an em-dash which takes up four bytes. We used
+        // to panic since we tried to index into the character.
+        assert_eq!(wrap("x – x", 1), vec!["x", "–", "x"]);
+    }
+}

src/output/textwrap/word_separators.rs

@@ -0,0 +1,91 @@
+pub(crate) fn find_words_ascii_space(line: &str) -> impl Iterator<Item = &'_ str> + '_ {
+    let mut start = 0;
+    let mut in_whitespace = false;
+    let mut char_indices = line.char_indices();
+
+    std::iter::from_fn(move || {
+        for (idx, ch) in char_indices.by_ref() {
+            if in_whitespace && ch != ' ' {
+                let word = &line[start..idx];
+                start = idx;
+                in_whitespace = ch == ' ';
+                return Some(word);
+            }
+
+            in_whitespace = ch == ' ';
+        }
+
+        if start < line.len() {
+            let word = &line[start..];
+            start = line.len();
+            return Some(word);
+        }
+
+        None
+    })
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    macro_rules! test_find_words {
+        ($ascii_name:ident,
+         $([ $line:expr, $ascii_words:expr ]),+) => {
+            #[test]
+            fn $ascii_name() {
+                $(
+                    let expected_words: Vec<&str> = $ascii_words.to_vec();
+                    let actual_words = find_words_ascii_space($line)
+                        .collect::<Vec<_>>();
+                    assert_eq!(actual_words, expected_words, "Line: {:?}", $line);
+                )+
+            }
+        };
+    }
+
+    test_find_words!(ascii_space_empty, ["", []]);
+
+    test_find_words!(ascii_single_word, ["foo", ["foo"]]);
+
+    test_find_words!(ascii_two_words, ["foo bar", ["foo ", "bar"]]);
+
+    test_find_words!(
+        ascii_multiple_words,
+        ["foo bar", ["foo ", "bar"]],
+        ["x y z", ["x ", "y ", "z"]]
+    );
+
+    test_find_words!(ascii_only_whitespace, [" ", [" "]], ["    ", ["    "]]);
+
+    test_find_words!(
+        ascii_inter_word_whitespace,
+        ["foo   bar", ["foo   ", "bar"]]
+    );
+
+    test_find_words!(ascii_trailing_whitespace, ["foo   ", ["foo   "]]);
+
+    test_find_words!(ascii_leading_whitespace, ["   foo", ["   ", "foo"]]);
+
+    test_find_words!(
+        ascii_multi_column_char,
+        ["\u{1f920}", ["\u{1f920}"]] // cowboy emoji 🤠
+    );
+
+    test_find_words!(
+        ascii_hyphens,
+        ["foo-bar", ["foo-bar"]],
+        ["foo- bar", ["foo- ", "bar"]],
+        ["foo - bar", ["foo ", "- ", "bar"]],
+        ["foo -bar", ["foo ", "-bar"]]
+    );
+
+    test_find_words!(ascii_newline, ["foo\nbar", ["foo\nbar"]]);
+
+    test_find_words!(ascii_tab, ["foo\tbar", ["foo\tbar"]]);
+
+    test_find_words!(
+        ascii_non_breaking_space,
+        ["foo\u{00A0}bar", ["foo\u{00A0}bar"]]
+    );
+}

src/output/textwrap/wrap_algorithms.rs

@@ -0,0 +1,44 @@
+use super::core::display_width;
+
+#[derive(Debug)]
+pub(crate) struct LineWrapper {
+    line_width: usize,
+    hard_width: usize,
+}
+
+impl LineWrapper {
+    pub(crate) fn new(hard_width: usize) -> Self {
+        Self {
+            line_width: 0,
+            hard_width,
+        }
+    }
+
+    pub(crate) fn reset(&mut self) {
+        self.line_width = 0;
+    }
+
+    pub(crate) fn wrap<'w>(&mut self, mut words: Vec<&'w str>) -> Vec<&'w str> {
+        let mut i = 0;
+        while i < words.len() {
+            let word = &words[i];
+            let trimmed = word.trim_end();
+            let word_width = display_width(trimmed);
+            let trimmed_delta = word.len() - trimmed.len();
+            if i != 0 && self.hard_width < self.line_width + word_width {
+                if 0 < i {
+                    let last = i - 1;
+                    let trimmed = words[last].trim_end();
+                    words[last] = trimmed;
+                }
+                words.insert(i, "\n");
+                i += 1;
+                self.reset();
+            }
+            self.line_width += word_width + trimmed_delta;
+
+            i += 1;
+        }
+        words
+    }
+}