Add --no-* negation flags for boolean CLI options

src/cli.rs

@@ -96,13 +96,16 @@ pub struct Opt {
     /// See: <https://docs.rs/chrono/latest/chrono/format/strftime/index.html>
     pub blame_timestamp_output_format: Option<String>,
 
-    #[arg(long = "color-only")]
+    #[arg(long = "color-only", overrides_with = "no_color_only")]
     /// Do not alter the input structurally in any way.
     ///
     /// But color and highlight hunk lines according to your delta configuration. This is mainly
     /// intended for other tools that use delta.
     pub color_only: bool,
 
+    #[arg(long = "no-color-only", overrides_with = "color_only", hide = true)]
+    pub no_color_only: bool,
+
     #[arg(long = "config", default_value = "", value_name = "PATH", value_hint = ValueHint::FilePath)]
     /// Load the config file at PATH instead of ~/.gitconfig.
     pub config: String,
@@ -184,18 +187,32 @@ pub struct Opt {
     /// doesn't support it, then delta will fall back to `diff` instead of `git diff`.
     pub diff_args: String,
 
-    #[arg(long = "diff-highlight")]
+    #[arg(long = "diff-highlight", overrides_with = "no_diff_highlight")]
     /// Emulate diff-highlight.
     ///
     /// <https://github.com/git/git/tree/master/contrib/diff-highlight>
     pub diff_highlight: bool,
 
-    #[arg(long = "diff-so-fancy")]
+    #[arg(
+        long = "no-diff-highlight",
+        overrides_with = "diff_highlight",
+        hide = true
+    )]
+    pub no_diff_highlight: bool,
+
+    #[arg(long = "diff-so-fancy", overrides_with = "no_diff_so_fancy")]
     /// Emulate diff-so-fancy.
     ///
     /// <https://github.com/so-fancy/diff-so-fancy>
     pub diff_so_fancy: bool,
 
+    #[arg(
+        long = "no-diff-so-fancy",
+        overrides_with = "diff_so_fancy",
+        hide = true
+    )]
+    pub no_diff_so_fancy: bool,
+
     #[arg(long = "diff-stat-align-width", default_value = "48", value_name = "N")]
     /// Width allocated for file paths in a diff stat section.
     ///
@@ -406,7 +423,7 @@ pub struct Opt {
     /// Used in the default value of navigate-regex.
     pub hunk_label: String,
 
-    #[arg(long = "hyperlinks")]
+    #[arg(long = "hyperlinks", overrides_with = "no_hyperlinks")]
     /// Render commit hashes, file names, and line numbers as hyperlinks.
     ///
     /// Following the hyperlink spec for terminal emulators:
@@ -420,6 +437,9 @@ pub struct Opt {
     /// <https://github.com/dandavison/tmux>).
     pub hyperlinks: bool,
 
+    #[arg(long = "no-hyperlinks", overrides_with = "hyperlinks", hide = true)]
+    pub no_hyperlinks: bool,
+
     #[arg(long = "hyperlinks-commit-link-format", value_name = "FMT")]
     /// Format string for commit hyperlinks (requires --hyperlinks).
     ///
@@ -466,13 +486,23 @@ pub struct Opt {
     /// Git's --color-moved feature. Set this to "false" to disable this behavior.
     pub inspect_raw_lines: String,
 
-    #[arg(long = "keep-plus-minus-markers")]
+    #[arg(
+        long = "keep-plus-minus-markers",
+        overrides_with = "no_keep_plus_minus_markers"
+    )]
     /// Prefix added/removed lines with a +/- character, as git does.
     ///
     /// By default, delta does not emit any prefix, so code can be copied directly from delta's
     /// output.
     pub keep_plus_minus_markers: bool,
 
+    #[arg(
+        long = "no-keep-plus-minus-markers",
+        overrides_with = "keep_plus_minus_markers",
+        hide = true
+    )]
+    pub no_keep_plus_minus_markers: bool,
+
     #[arg(long = "light")]
     /// Use default colors appropriate for a light terminal background.
     ///
@@ -497,12 +527,15 @@ pub struct Opt {
     /// --width=variable is given.
     pub line_fill_method: Option<String>,
 
-    #[arg(short = 'n', long = "line-numbers")]
+    #[arg(short = 'n', long = "line-numbers", overrides_with = "no_line_numbers")]
     /// Display line numbers next to the diff.
     ///
     /// See LINE NUMBERS section.
     pub line_numbers: bool,
 
+    #[arg(long = "no-line-numbers", overrides_with = "line_numbers", hide = true)]
+    pub no_line_numbers: bool,
+
     #[arg(
         long = "line-numbers-left-format",
         default_value = "{nm:^4}⋮",
@@ -722,13 +755,16 @@ pub struct Opt {
     /// See STYLES section.
     pub minus_style: String,
 
-    #[arg(long = "navigate")]
+    #[arg(long = "navigate", overrides_with = "no_navigate")]
     /// Activate diff navigation.
     ///
     /// Use n to jump forwards and N to jump backwards. To change the file labels used see
     /// --file-added-label, --file-copied-label, --file-modified-label, --file-removed-label, --file-renamed-label.
     pub navigate: bool,
 
+    #[arg(long = "no-navigate", overrides_with = "navigate", hide = true)]
+    pub no_navigate: bool,
+
     #[arg(long = "navigate-regex", value_name = "REGEX")]
     /// Regular expression defining navigation stop points.
     pub navigate_regex: Option<String>,
@@ -805,18 +841,28 @@ pub struct Opt {
     /// See STYLES section.
     pub plus_style: String,
 
-    #[arg(long = "raw")]
+    #[arg(long = "raw", overrides_with = "no_raw")]
     /// Do not alter the input in any way.
     ///
     /// This is mainly intended for testing delta.
     pub raw: bool,
 
-    #[arg(long = "relative-paths")]
+    #[arg(long = "no-raw", overrides_with = "raw", hide = true)]
+    pub no_raw: bool,
+
+    #[arg(long = "relative-paths", overrides_with = "no_relative_paths")]
     /// Output all file paths relative to the current directory.
     ///
     /// This means that they will resolve correctly when clicked on or used in shell commands.
     pub relative_paths: bool,
 
+    #[arg(
+        long = "no-relative-paths",
+        overrides_with = "relative_paths",
+        hide = true
+    )]
+    pub no_relative_paths: bool,
+
     #[arg(long = "right-arrow", default_value = "⟶  ", value_name = "STRING")]
     /// Text to display with a changed file path.
     ///
@@ -856,10 +902,13 @@ pub struct Opt {
     /// shown, use --dark or --light, or both, on the command line together with this option.
     pub show_themes: bool,
 
-    #[arg(short = 's', long = "side-by-side")]
+    #[arg(short = 's', long = "side-by-side", overrides_with = "no_side_by_side")]
     /// Display diffs in side-by-side layout.
     pub side_by_side: bool,
 
+    #[arg(long = "no-side-by-side", overrides_with = "side_by_side", hide = true)]
+    pub no_side_by_side: bool,
+
     #[arg(long = "syntax-theme", value_name = "SYNTAX_THEME")]
     /// The syntax-highlighting theme to use.
     ///

src/handlers/blame.rs

@@ -313,8 +313,9 @@ pub fn format_blame_line_number(
     let mut result = String::new();
 
     // depends on defaults being set when parsing arguments
-    let line_number = if let Some(width) = format.width {
-        format::pad(line_number, width, format.alignment_spec.unwrap(), None)
+    let line_number = if let (Some(width), Some(alignment)) = (format.width, format.alignment_spec)
+    {
+        format::pad(line_number, width, alignment, None)
     } else {
         String::new()
     };

src/options/set.rs

@@ -50,6 +50,17 @@ macro_rules! set_options {
                 "dark",
                 "light",
                 "syntax-theme",
+                // --no-* negation flags (handled in apply_no_flag_overrides)
+                "no-color-only",
+                "no-diff-highlight",
+                "no-diff-so-fancy",
+                "no-hyperlinks",
+                "no-keep-plus-minus-markers",
+                "no-line-numbers",
+                "no-navigate",
+                "no-raw",
+                "no-relative-paths",
+                "no-side-by-side",
             ]);
             let expected_option_names: HashSet<_> = $expected_option_name_map
                 .values()
@@ -234,6 +245,10 @@ pub fn set_options(
         true
     );
 
+    // Apply --no-* flag overrides. When a --no-* flag is user-supplied, it forces
+    // the corresponding option to false, overriding any gitconfig value.
+    apply_no_flag_overrides(opt, arg_matches);
+
     // Setting ComputedValues
     set_widths_and_isatty(opt);
     set_true_color(opt);
@@ -253,6 +268,26 @@ pub fn set_options(
     }
 }
 
+fn apply_no_flag_overrides(opt: &mut cli::Opt, arg_matches: &clap::ArgMatches) {
+    macro_rules! apply_no_flag {
+        ($no_field:ident, $field:ident) => {
+            if config::user_supplied_option(stringify!($no_field), arg_matches) {
+                opt.$field = false;
+            }
+        };
+    }
+    apply_no_flag!(no_color_only, color_only);
+    apply_no_flag!(no_diff_highlight, diff_highlight);
+    apply_no_flag!(no_diff_so_fancy, diff_so_fancy);
+    apply_no_flag!(no_hyperlinks, hyperlinks);
+    apply_no_flag!(no_keep_plus_minus_markers, keep_plus_minus_markers);
+    apply_no_flag!(no_line_numbers, line_numbers);
+    apply_no_flag!(no_navigate, navigate);
+    apply_no_flag!(no_raw, raw);
+    apply_no_flag!(no_relative_paths, relative_paths);
+    apply_no_flag!(no_side_by_side, side_by_side);
+}
+
 #[allow(non_snake_case)]
 fn set__light__dark__syntax_theme__options(
     opt: &mut cli::Opt,
@@ -373,28 +408,28 @@ fn gather_features(
 
     // Gather builtin feature flags supplied on command line.
     // TODO: Iterate over programmatically-obtained names of builtin features.
-    if opt.raw {
+    if opt.raw && !opt.no_raw {
         gather_builtin_features_recursively("raw", &mut features, builtin_features, opt);
     }
-    if opt.color_only {
+    if opt.color_only && !opt.no_color_only {
         gather_builtin_features_recursively("color-only", &mut features, builtin_features, opt);
     }
-    if opt.diff_highlight {
+    if opt.diff_highlight && !opt.no_diff_highlight {
         gather_builtin_features_recursively("diff-highlight", &mut features, builtin_features, opt);
     }
-    if opt.diff_so_fancy {
+    if opt.diff_so_fancy && !opt.no_diff_so_fancy {
         gather_builtin_features_recursively("diff-so-fancy", &mut features, builtin_features, opt);
     }
-    if opt.hyperlinks {
+    if opt.hyperlinks && !opt.no_hyperlinks {
         gather_builtin_features_recursively("hyperlinks", &mut features, builtin_features, opt);
     }
-    if opt.line_numbers {
+    if opt.line_numbers && !opt.no_line_numbers {
         gather_builtin_features_recursively("line-numbers", &mut features, builtin_features, opt);
     }
-    if opt.navigate {
+    if opt.navigate && !opt.no_navigate {
         gather_builtin_features_recursively("navigate", &mut features, builtin_features, opt);
     }
-    if opt.side_by_side {
+    if opt.side_by_side && !opt.no_side_by_side {
         gather_builtin_features_recursively("side-by-side", &mut features, builtin_features, opt);
     }
 
@@ -806,6 +841,64 @@ pub mod tests {
         remove_file(git_config_path).unwrap();
     }
 
+    #[test]
+    fn test_no_flags_override_gitconfig() {
+        let git_config_contents = b"
+[delta]
+    side-by-side = true
+    line-numbers = true
+    navigate = true
+    hyperlinks = true
+    keep-plus-minus-markers = true
+    raw = true
+    relative-paths = true
+";
+        let git_config_path = "delta__test_no_flags_override_gitconfig.gitconfig";
+
+        let opt = integration_test_utils::make_options_from_args_and_git_config(
+            &[
+                "--no-side-by-side",
+                "--no-line-numbers",
+                "--no-navigate",
+                "--no-hyperlinks",
+                "--no-keep-plus-minus-markers",
+                "--no-raw",
+                "--no-relative-paths",
+            ],
+            Some(git_config_contents),
+            Some(git_config_path),
+        );
+
+        assert!(!opt.side_by_side);
+        assert!(!opt.line_numbers);
+        assert!(!opt.navigate);
+        assert!(!opt.hyperlinks);
+        assert!(!opt.keep_plus_minus_markers);
+        assert!(!opt.raw);
+        assert!(!opt.relative_paths);
+
+        remove_file(git_config_path).unwrap();
+    }
+
+    #[test]
+    fn test_no_flags_last_flag_wins() {
+        // --no-side-by-side followed by --side-by-side should enable it
+        let opt = integration_test_utils::make_options_from_args_and_git_config(
+            &["--no-side-by-side", "--side-by-side"],
+            None,
+            None,
+        );
+        assert!(opt.side_by_side);
+
+        // --side-by-side followed by --no-side-by-side should disable it
+        let opt = integration_test_utils::make_options_from_args_and_git_config(
+            &["--side-by-side", "--no-side-by-side"],
+            None,
+            None,
+        );
+        assert!(!opt.side_by_side);
+    }
+
     #[test]
     fn test_width_in_git_config_is_honored() {
         let git_config_contents = b"