Merge pull request #3812 from greymoth-jp/fix/list-languages-narrow-width-underflow

fix: avoid usize underflow in --list-languages at narrow terminal width

CHANGELOG.md

@@ -46,6 +46,7 @@
 - Fixed syntax tests path, see #3610 (@foxfromworld)
 - Fix zsh tab completion word-splitting language names containing spaces (e.g. `HTML (Jinja2)`, `Apache Conf`), see #3693 (@YoshKoz)
 - Fix zsh tab completion offering invalid `-l` arguments (file globs, paths, hidden filenames) sourced from the second column of `--list-languages`. Closes #3735, see #3737 (@truffle-dev)
+- Fix `usize` underflow in `--list-languages` when `--terminal-width` is smaller than the longest language name, see #3812 (@greymoth-jp)
 
 ## Other
 - Use git version of cross. See #3533 (@OctopusET)

src/bin/bat/main.rs

@@ -152,7 +152,14 @@ pub fn get_languages(config: &Config, cache_dir: &Path) -> Result<String> {
         let comma_separator = ", ";
         let separator = " ";
         // Line-wrapping for the possible file extension overflow.
-        let desired_width = config.term_width - longest - separator.len();
+        // Clamp instead of subtracting: a tiny `--terminal-width` (smaller than the
+        // longest language name) would otherwise underflow `usize` and wrap to a huge
+        // value, silently disabling wrapping (and panicking in debug/overflow-checked
+        // builds). Mirrors the `saturating_sub` fix applied to `print_snip` in #3804.
+        let desired_width = config
+            .term_width
+            .saturating_sub(longest)
+            .saturating_sub(separator.len());
 
         let style = if config.colored_output {
             Green.normal()