use "search_result" style to colorize matching strings (fixes #9275) (#9326)

This change introduces new `search_result` style supported in the color
config. The change also removes obsolete check for `config.ls_colors`
for computing the style. `config.ls_colors` has been removed last year,
so this removes the reference to the obsolete flag, along with a cleanup
that removes all the code that used to rely on ls_colors for
highlighting search results.


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crates/nu-cmd-lang/src/core_commands/help.rs

@@ -2,10 +2,7 @@ use crate::help_aliases::help_aliases;
 use crate::help_commands::help_commands;
 use crate::help_modules::help_modules;
 use fancy_regex::Regex;
-use nu_ansi_term::{
+use nu_ansi_term::Style;
-    Color::{Red, White},
-    Style,
-};
 use nu_engine::CallExt;
 use nu_protocol::{
     ast::Call,
@@ -141,6 +138,7 @@ pub fn highlight_search_in_table(
     search_string: &str,
     searched_cols: &[&str],
     string_style: &Style,
+    highlight_style: &Style,
 ) -> Result<Vec<Value>, ShellError> {
     let orig_search_string = search_string;
     let search_string = search_string.to_lowercase();
@@ -164,7 +162,12 @@ pub fn highlight_search_in_table(
                     if let Value::String { val: s, span } = val {
                         if s.to_lowercase().contains(&search_string) {
                             *val = Value::String {
-                                val: highlight_search_string(s, orig_search_string, string_style)?,
+                                val: highlight_search_string(
+                                    s,
+                                    orig_search_string,
+                                    string_style,
+                                    highlight_style,
+                                )?,
                                 span: *span,
                             };
                             Ok(true)
@@ -200,6 +203,7 @@ pub fn highlight_search_string(
     haystack: &str,
     needle: &str,
     string_style: &Style,
+    highlight_style: &Style,
 ) -> Result<String, ShellError> {
     let regex_string = format!("(?i){needle}");
     let regex = match Regex::new(&regex_string) {
@@ -217,7 +221,6 @@ pub fn highlight_search_string(
     // strip haystack to remove existing ansi style
     let stripped_haystack = nu_utils::strip_ansi_likely(haystack);
     let mut last_match_end = 0;
-    let style = Style::new().fg(White).on(Red);
     let mut highlighted = String::new();
 
     for cap in regex.captures_iter(stripped_haystack.as_ref()) {
@@ -236,7 +239,11 @@ pub fn highlight_search_string(
                         .paint(&stripped_haystack[last_match_end..start])
                         .to_string(),
                 );
-                highlighted.push_str(&style.paint(&stripped_haystack[start..end]).to_string());
+                highlighted.push_str(
+                    &highlight_style
+                        .paint(&stripped_haystack[start..end])
+                        .to_string(),
+                );
                 last_match_end = end;
             }
             Err(e) => {

crates/nu-cmd-lang/src/core_commands/help_aliases.rs

@@ -84,11 +84,18 @@ pub fn help_aliases(
     // Also note that this sample string is passed into user-written code (the closure that may or may not be
     // defined for "string").
     let string_style = style_computer.compute("string", &Value::string("search result", head));
+    let highlight_style =
+        style_computer.compute("search_result", &Value::string("search result", head));
 
     if let Some(f) = find {
         let all_cmds_vec = build_help_aliases(engine_state, stack, head);
-        let found_cmds_vec =
+        let found_cmds_vec = highlight_search_in_table(
-            highlight_search_in_table(all_cmds_vec, &f.item, &["name", "usage"], &string_style)?;
+            all_cmds_vec,
+            &f.item,
+            &["name", "usage"],
+            &string_style,
+            &highlight_style,
+        )?;
 
         return Ok(found_cmds_vec
             .into_iter()

crates/nu-cmd-lang/src/core_commands/help_commands.rs

@@ -65,6 +65,8 @@ pub fn help_commands(
     // Also note that this sample string is passed into user-written code (the closure that may or may not be
     // defined for "string").
     let string_style = style_computer.compute("string", &Value::string("search result", head));
+    let highlight_style =
+        style_computer.compute("search_result", &Value::string("search result", head));
 
     if let Some(f) = find {
         let all_cmds_vec = build_help_commands(engine_state, head);
@@ -73,6 +75,7 @@ pub fn help_commands(
             &f.item,
             &["name", "usage", "search_terms"],
             &string_style,
+            &highlight_style,
         )?;
 
         return Ok(found_cmds_vec

crates/nu-cmd-lang/src/core_commands/help_externs.rs

@@ -84,11 +84,18 @@ pub fn help_externs(
     // Also note that this sample string is passed into user-written code (the closure that may or may not be
     // defined for "string").
     let string_style = style_computer.compute("string", &Value::string("search result", head));
+    let highlight_style =
+        style_computer.compute("search_result", &Value::string("search result", head));
 
     if let Some(f) = find {
         let all_cmds_vec = build_help_externs(engine_state, stack, head);
-        let found_cmds_vec =
+        let found_cmds_vec = highlight_search_in_table(
-            highlight_search_in_table(all_cmds_vec, &f.item, &["name", "usage"], &string_style)?;
+            all_cmds_vec,
+            &f.item,
+            &["name", "usage"],
+            &string_style,
+            &highlight_style,
+        )?;
 
         return Ok(found_cmds_vec
             .into_iter()

crates/nu-cmd-lang/src/core_commands/help_modules.rs

@@ -90,11 +90,18 @@ pub fn help_modules(
     // Also note that this sample string is passed into user-written code (the closure that may or may not be
     // defined for "string").
     let string_style = style_computer.compute("string", &Value::string("search result", head));
+    let highlight_style =
+        style_computer.compute("search_result", &Value::string("search result", head));
 
     if let Some(f) = find {
         let all_cmds_vec = build_help_modules(engine_state, stack, head);
-        let found_cmds_vec =
+        let found_cmds_vec = highlight_search_in_table(
-            highlight_search_in_table(all_cmds_vec, &f.item, &["name", "usage"], &string_style)?;
+            all_cmds_vec,
+            &f.item,
+            &["name", "usage"],
+            &string_style,
+            &highlight_style,
+        )?;
 
         return Ok(found_cmds_vec
             .into_iter()

crates/nu-color-config/src/style_computer.rs

@@ -163,6 +163,7 @@ impl<'a> StyleComputer<'a> {
             ("list".to_string(), ComputableStyle::Static(Color::White.normal())),
             ("block".to_string(), ComputableStyle::Static(Color::White.normal())),
             ("hints".to_string(), ComputableStyle::Static(Color::DarkGray.normal())),
+            ("search_result".to_string(), ComputableStyle::Static(Color::White.normal().on(Color::Red))),
         ]);
 
         for (key, value) in &config.color_config {

crates/nu-command/src/filters/find.rs

@@ -1,17 +1,15 @@
 use nu_cmd_lang::help::highlight_search_string;
 
 use fancy_regex::Regex;
-use lscolors::{Color as LsColors_Color, LsColors, Style as LsColors_Style};
+use nu_ansi_term::Style;
-use nu_ansi_term::{Color, Style};
 use nu_color_config::StyleComputer;
-use nu_engine::{env_to_string, CallExt};
+use nu_engine::CallExt;
 use nu_protocol::{
     ast::Call,
     engine::{Command, EngineState, Stack},
     Category, Config, Example, IntoInterruptiblePipelineData, IntoPipelineData, ListStream,
     PipelineData, ShellError, Signature, Span, SyntaxShape, Type, Value,
 };
-use nu_utils::get_ls_colors;
 
 #[derive(Clone)]
 pub struct Find;
@@ -300,7 +298,7 @@ fn highlight_terms_in_record_with_search_columns(
     config: &Config,
     terms: &[Value],
     string_style: Style,
-    ls_colors: &LsColors,
+    highlight_style: Style,
 ) -> Value {
     let cols_to_search = if search_cols.is_empty() {
         cols.to_vec()
@@ -316,18 +314,11 @@ fn highlight_terms_in_record_with_search_columns(
             let term_str = term.into_string("", config);
             let output_value =
                 if contains_ignore_case(&val_str, &term_str) && cols_to_search.contains(cur_col) {
-                    let (value_to_highlight, highlight_string_style) = if config.use_ls_colors {
-                        // Get the original LS_COLORS color
-                        get_colored_value_and_string_style(ls_colors, &val_str, &string_style)
-                    } else {
-                        // No LS_COLORS support, so just use the original value
-                        (val_str.clone(), string_style)
-                    };
-
                     let highlighted_str = match highlight_search_string(
-                        &value_to_highlight,
+                        &val_str,
                         &term_str,
-                        &highlight_string_style,
+                        &string_style,
+                        &highlight_style,
                     ) {
                         Ok(highlighted_str) => highlighted_str,
                         Err(_) => string_style.paint(term_str).to_string(),
@@ -350,24 +341,6 @@ fn highlight_terms_in_record_with_search_columns(
     }
 }
 
-fn get_colored_value_and_string_style(
-    ls_colors: &LsColors,
-    val_str: &str,
-    string_style: &Style,
-) -> (String, Style) {
-    let style = ls_colors.style_for_path(val_str);
-    let ansi_style = style
-        .map(LsColors_Style::to_nu_ansi_term_style)
-        .unwrap_or_default();
-
-    let ls_colored_val = ansi_style.paint(val_str).to_string();
-
-    let ansi_term_style = style
-        .map(to_nu_ansi_term_style)
-        .unwrap_or_else(|| *string_style);
-    (ls_colored_val, ansi_term_style)
-}
-
 fn contains_ignore_case(string: &str, substring: &str) -> bool {
     string.to_lowercase().contains(&substring.to_lowercase())
 }
@@ -401,12 +374,8 @@ fn find_with_rest_and_highlight(
     // Also note that this sample string is passed into user-written code (the closure that may or may not be
     // defined for "string").
     let string_style = style_computer.compute("string", &Value::string("search result", span));
-
+    let highlight_style =
-    let ls_colors_env_str = match stack.get_env_var(&engine_state, "LS_COLORS") {
+        style_computer.compute("search_result", &Value::string("search result", span));
-        Some(v) => Some(env_to_string("LS_COLORS", &v, &engine_state, stack)?),
-        None => None,
-    };
-    let ls_colors = get_ls_colors(ls_colors_env_str);
 
     let cols_to_search_in_map = match call.get_flag(&engine_state, stack, "columns")? {
         Some(cols) => cols,
@@ -429,7 +398,7 @@ fn find_with_rest_and_highlight(
                             &config,
                             &terms,
                             string_style,
-                            &ls_colors,
+                            highlight_style,
                         )
                     }
                     _ => x,
@@ -461,7 +430,7 @@ fn find_with_rest_and_highlight(
                             &config,
                             &terms,
                             string_style,
-                            &ls_colors,
+                            highlight_style,
                         )
                     }
                     _ => x,
@@ -504,6 +473,7 @@ fn find_with_rest_and_highlight(
                                                 line,
                                                 &term_str,
                                                 &string_style,
+                                                &highlight_style,
                                             )?,
                                             span,
                                         })
@@ -622,47 +592,6 @@ fn record_matches_term(
     })
 }
 
-fn to_nu_ansi_term_style(style: &LsColors_Style) -> Style {
-    fn to_nu_ansi_term_color(color: &LsColors_Color) -> Color {
-        match *color {
-            LsColors_Color::Fixed(n) => Color::Fixed(n),
-            LsColors_Color::RGB(r, g, b) => Color::Rgb(r, g, b),
-            LsColors_Color::Black => Color::Black,
-            LsColors_Color::Red => Color::Red,
-            LsColors_Color::Green => Color::Green,
-            LsColors_Color::Yellow => Color::Yellow,
-            LsColors_Color::Blue => Color::Blue,
-            LsColors_Color::Magenta => Color::Magenta,
-            LsColors_Color::Cyan => Color::Cyan,
-            LsColors_Color::White => Color::White,
-
-            // Below items are a rough translations to 256 colors as
-            // nu-ansi-term do not have bright variants
-            LsColors_Color::BrightBlack => Color::Fixed(8),
-            LsColors_Color::BrightRed => Color::Fixed(9),
-            LsColors_Color::BrightGreen => Color::Fixed(10),
-            LsColors_Color::BrightYellow => Color::Fixed(11),
-            LsColors_Color::BrightBlue => Color::Fixed(12),
-            LsColors_Color::BrightMagenta => Color::Fixed(13),
-            LsColors_Color::BrightCyan => Color::Fixed(14),
-            LsColors_Color::BrightWhite => Color::Fixed(15),
-        }
-    }
-
-    Style {
-        foreground: style.foreground.as_ref().map(to_nu_ansi_term_color),
-        background: style.background.as_ref().map(to_nu_ansi_term_color),
-        is_bold: style.font_style.bold,
-        is_dimmed: style.font_style.dimmed,
-        is_italic: style.font_style.italic,
-        is_underline: style.font_style.underline,
-        is_blink: style.font_style.slow_blink || style.font_style.rapid_blink,
-        is_reverse: style.font_style.reverse,
-        is_hidden: style.font_style.hidden,
-        is_strikethrough: style.font_style.strikethrough,
-    }
-}
-
 #[cfg(test)]
 mod tests {
     use super::*;

crates/nu-utils/src/sample_config/default_config.nu

@@ -52,6 +52,7 @@ let dark_theme = {
     list: white
     block: white
     hints: dark_gray
+    search_result: {bg: red fg: white}
 
     shape_and: purple_bold
     shape_binary: purple_bold
@@ -136,6 +137,7 @@ let light_theme = {
     list: white
     block: white
     hints: dark_gray
+    search_result: {fg: white bg: red}
 
     shape_and: purple_bold
     shape_binary: purple_bold