feat(shell): Add style config for shell module (#3108)

* add style config for shell module

* update shell docs

* fix formatting

* update tests

3 files changed, 64 insertions, 22 deletions

diff --git a/docs/config/README.md b/docs/config/README.md
index fbabf80dd..68ffac0b8 100644
--- a/docs/config/README.md
+++ b/docs/config/README.md
@@ -2707,25 +2707,29 @@ To enable it, set `disabled` to `false` in your configuration file.
 
 ### Options
 
-| Option                 | Default         | Description                                                  |
-| ---------------------- | --------------- | ------------------------------------------------------------ |
-| `bash_indicator`       | `"bsh"`         | A format string used to represent bash.                      |
-| `fish_indicator`       | `"fsh"`         | A format string used to represent fish.                      |
-| `zsh_indicator`        | `"zsh"`         | A format string used to represent zsh.                       |
-| `powershell_indicator` | `"psh"`         | A format string used to represent powershell.                |
-| `ion_indicator`        | `"ion"`         | A format string used to represent ion.                       |
-| `elvish_indicator`     | `"esh"`         | A format string used to represent elvish.                    |
-| `tcsh_indicator`       | `"tsh"`         | A format string used to represent tcsh.                      |
-| `xonsh_indicator`      | `"xsh"`         | A format string used to represent xonsh.                     |
-| `unknown_indicator`    | `""`            | The default value to be displayed when the shell is unknown. |
-| `format`               | `"$indicator "` | The format for the module.                                   |
-| `disabled`             | `true`          | Disables the `shell` module.                                 |
+| Option                 | Default                   | Description                                                  |
+| ---------------------- | ------------------------- | ------------------------------------------------------------ |
+| `bash_indicator`       | `bsh`                     | A format string used to represent bash.                      |
+| `fish_indicator`       | `fsh`                     | A format string used to represent fish.                      |
+| `zsh_indicator`        | `zsh`                     | A format string used to represent zsh.                       |
+| `powershell_indicator` | `psh`                     | A format string used to represent powershell.                |
+| `ion_indicator`        | `ion`                     | A format string used to represent ion.                       |
+| `elvish_indicator`     | `esh`                     | A format string used to represent elvish.                    |
+| `tcsh_indicator`       | `tsh`                     | A format string used to represent tcsh.                      |
+| `xonsh_indicator`      | `xsh`                     | A format string used to represent xonsh.                     |
+| `unknown_indicator`    |                           | The default value to be displayed when the shell is unknown. |
+| `format`               | `"[$indicator]($style) "` | The format for the module.                                   |
+| `style`                | `"white bold"`            | The style for the module.                                    |
+| `disabled`             | `true`                    | Disables the `shell` module.                                 |
 
 ### Variables
 
 | Variable    | Default | Description                                                |
 | ----------- | ------- | ---------------------------------------------------------- |
 | indicator   |         | Mirrors the value of `indicator` for currently used shell. |
+| style\*     |         | Mirrors the value of option `style`.                       |
+
+\*: This variable can only be used as a part of a style string
 
 ### Examples
 
@@ -2736,6 +2740,7 @@ To enable it, set `disabled` to `false` in your configuration file.
 fish_indicator = ""
 powershell_indicator = "_"
 unknown_indicator = "mystery shell"
+style = "cyan bold"
 disabled = false
 ```
 
diff --git a/src/configs/shell.rs b/src/configs/shell.rs
index 818130ae3..9e5c7b18d 100644
--- a/src/configs/shell.rs
+++ b/src/configs/shell.rs
@@ -16,13 +16,14 @@ pub struct ShellConfig<'a> {
     pub nu_indicator: &'a str,
     pub xonsh_indicator: &'a str,
     pub unknown_indicator: &'a str,
+    pub style: &'a str,
     pub disabled: bool,
 }
 
 impl<'a> Default for ShellConfig<'a> {
     fn default() -> Self {
         ShellConfig {
-            format: "$indicator ",
+            format: "[$indicator]($style) ",
             bash_indicator: "bsh",
             fish_indicator: "fsh",
             zsh_indicator: "zsh",
@@ -33,6 +34,7 @@ impl<'a> Default for ShellConfig<'a> {
             nu_indicator: "nu",
             xonsh_indicator: "xsh",
             unknown_indicator: "",
+            style: "white bold",
             disabled: true,
         }
     }
diff --git a/src/modules/shell.rs b/src/modules/shell.rs
index 0b141ec8a..9e99cd3e0 100644
--- a/src/modules/shell.rs
+++ b/src/modules/shell.rs
@@ -30,6 +30,10 @@ pub fn module<'a>(context: &'a Context) -> Option<Module<'a>> {
                 },
                 _ => None,
             })
+            .map_style(|variable| match variable {
+                "style" => Some(Ok(config.style)),
+                _ => None,
+            })
             .map(|var| match var {
                 "bash_indicator" => Some(Ok(config.bash_indicator)),
                 "fish_indicator" => Some(Ok(config.fish_indicator)),
@@ -80,7 +84,7 @@ mod tests {
 
     #[test]
     fn test_bash_default_format() {
-        let expected = Some(format!("{} ", "bsh"));
+        let expected = Some(format!("{} ", Color::White.bold().paint("bsh")));
         let actual = ModuleRenderer::new("shell")
             .shell(Shell::Bash)
             .config(toml::toml! {
@@ -109,7 +113,7 @@ mod tests {
 
     #[test]
     fn test_fish_default_format() {
-        let expected = Some(format!("{} ", "fsh"));
+        let expected = Some(format!("{} ", Color::White.bold().paint("fsh")));
         let actual = ModuleRenderer::new("shell")
             .shell(Shell::Fish)
             .config(toml::toml! {
@@ -138,7 +142,7 @@ mod tests {
 
     #[test]
     fn test_zsh_default_format() {
-        let expected = Some(format!("{} ", "zsh"));
+        let expected = Some(format!("{} ", Color::White.bold().paint("zsh")));
         let actual = ModuleRenderer::new("shell")
             .shell(Shell::Zsh)
             .config(toml::toml! {
@@ -167,7 +171,7 @@ mod tests {
 
     #[test]
     fn test_powershell_default_format() {
-        let expected = Some(format!("{} ", "psh"));
+        let expected = Some(format!("{} ", Color::White.bold().paint("psh")));
         let actual = ModuleRenderer::new("shell")
             .shell(Shell::PowerShell)
             .config(toml::toml! {
@@ -196,7 +200,7 @@ mod tests {
 
     #[test]
     fn test_ion_default_format() {
-        let expected = Some(format!("{} ", "ion"));
+        let expected = Some(format!("{} ", Color::White.bold().paint("ion")));
         let actual = ModuleRenderer::new("shell")
             .shell(Shell::Ion)
             .config(toml::toml! {
@@ -225,7 +229,7 @@ mod tests {
 
     #[test]
     fn test_elvish_default_format() {
-        let expected = Some(format!("{} ", "esh"));
+        let expected = Some(format!("{} ", Color::White.bold().paint("esh")));
         let actual = ModuleRenderer::new("shell")
             .shell(Shell::Elvish)
             .config(toml::toml! {
@@ -254,7 +258,7 @@ mod tests {
 
     #[test]
     fn test_nu_default_format() {
-        let expected = Some(format!("{} ", "nu"));
+        let expected = Some(format!("{} ", Color::White.bold().paint("nu")));
         let actual = ModuleRenderer::new("shell")
             .shell(Shell::Nu)
             .config(toml::toml! {
@@ -283,7 +287,7 @@ mod tests {
 
     #[test]
     fn test_xonsh_default_format() {
-        let expected = Some(format!("{} ", "xsh"));
+        let expected = Some(format!("{} ", Color::White.bold().paint("xsh")));
         let actual = ModuleRenderer::new("shell")
             .shell(Shell::Xonsh)
             .config(toml::toml! {
@@ -341,4 +345,35 @@ mod tests {
 
         assert_eq!(expected, actual);
     }
+
+    #[test]
+    fn test_default_style() {
+        let expected = Some(format!("{}", Color::White.bold().paint("fish")));
+        let actual = ModuleRenderer::new("shell")
+            .shell(Shell::Fish)
+            .config(toml::toml! {
+                [shell]
+                format = "[fish]($style)"
+                disabled = false
+            })
+            .collect();
+
+        assert_eq!(expected, actual);
+    }
+
+    #[test]
+    fn test_custom_style() {
+        let expected = Some(format!("{}", Color::Cyan.bold().paint("fish")));
+        let actual = ModuleRenderer::new("shell")
+            .shell(Shell::Fish)
+            .config(toml::toml! {
+                [shell]
+                format = "[fish]($style)"
+                style = "cyan bold"
+                disabled = false
+            })
+            .collect();
+
+        assert_eq!(expected, actual);
+    }
 }