feat(shlvl): add repeat_offset for repeated symbol (#5289)

Signed-off-by: Vivek Kushwaha <yoursvivek@users.noreply.github.com>

.github/config-schema.json

@@ -1499,6 +1499,7 @@
         "disabled": true,
         "format": "[$symbol$shlvl]($style) ",
         "repeat": false,
+        "repeat_offset": 0,
         "style": "bold yellow",
         "symbol": "↕️  ",
         "threshold": 2
@@ -5243,6 +5244,12 @@
           "default": false,
           "type": "boolean"
         },
+        "repeat_offset": {
+          "default": 0,
+          "type": "integer",
+          "format": "uint64",
+          "minimum": 0.0
+        },
         "style": {
           "default": "bold yellow",
           "type": "string"

docs/config/README.md

@@ -3773,11 +3773,12 @@ set to a number and meets or exceeds the specified threshold.
 ### Options
 
 | Option          | Default                      | Description                                                         |
-| ----------- | ---------------------------- | ------------------------------------------------------------- |
+| --------------- | ---------------------------- | ------------------------------------------------------------------- |
 | `threshold`     | `2`                          | Display threshold.                                                  |
 | `format`        | `'[$symbol$shlvl]($style) '` | The format for the module.                                          |
 | `symbol`        | `'↕️  '`                      | The symbol used to represent the `SHLVL`.                           |
 | `repeat`        | `false`                      | Causes `symbol` to be repeated by the current `SHLVL` amount.       |
+| `repeat_offset` | `0`                          | Decrements number of times `symbol` is repeated by the offset value |
 | `style`         | `'bold yellow'`              | The style for the module.                                           |
 | `disabled`      | `true`                       | Disables the `shlvl` module.                                        |
 
@@ -3802,6 +3803,22 @@ format = '$shlvl level(s) down'
 threshold = 3
 ```
 
+Using `repeat` and `repeat_offset` along with `character` module, one can get
+prompt like `❯❯❯` where last character is colored appropriately for return
+status code and preceeding characters are provided by `shlvl`.
+
+```toml
+# ~/.config/starship.toml
+
+[shlvl]
+disabled = false
+format = '[$symbol$shlvl]($style)'
+repeat = true
+symbol = '❯'
+repeat_offset = 1
+threshold = 0
+```
+
 ## Singularity
 
 The `singularity` module shows the current [Singularity](https://sylabs.io/singularity/) image, if inside a container

src/configs/shlvl.rs

@@ -12,6 +12,7 @@ pub struct ShLvlConfig<'a> {
     pub format: &'a str,
     pub symbol: &'a str,
     pub repeat: bool,
+    pub repeat_offset: u64,
     pub style: &'a str,
     pub disabled: bool,
 }
@@ -23,6 +24,7 @@ impl<'a> Default for ShLvlConfig<'a> {
             format: "[$symbol$shlvl]($style) ",
             symbol: "↕️  ", // extra space for emoji
             repeat: false,
+            repeat_offset: 0,
             style: "bold yellow",
             disabled: true,
         }

src/modules/shlvl.rs

@@ -22,11 +22,20 @@ pub fn module<'a>(context: &'a Context) -> Option<Module<'a>> {
 
     let shlvl_str = &shlvl.to_string();
 
-    let repeat_count = if config.repeat {
+    let mut repeat_count: usize = if config.repeat {
         shlvl.try_into().unwrap_or(1)
     } else {
         1
     };
+
+    if config.repeat_offset > 0 {
+        repeat_count =
+            repeat_count.saturating_sub(config.repeat_offset.try_into().unwrap_or(usize::MAX));
+        if repeat_count == 0 {
+            return None;
+        }
+    }
+
     let symbol = if repeat_count != 1 {
         Cow::Owned(config.symbol.repeat(repeat_count))
     } else {
@@ -219,4 +228,33 @@ mod tests {
 
         assert_eq!(expected, actual);
     }
+
+    #[test]
+    fn repeat_offset() {
+        fn get_actual(shlvl: usize, repeat_offset: usize, threshold: usize) -> Option<String> {
+            ModuleRenderer::new("shlvl")
+                .config(toml::toml! {
+                    [shlvl]
+                    format = "[$symbol]($style)"
+                    symbol = "~"
+                    repeat = true
+                    repeat_offset = repeat_offset
+                    disabled = false
+                    threshold = threshold
+                })
+                .env(SHLVL_ENV_VAR, format!("{}", shlvl))
+                .collect()
+        }
+
+        assert_eq!(
+            get_actual(2, 0, 0),
+            Some(format!("{}", style().paint("~~")))
+        );
+        assert_eq!(get_actual(2, 1, 0), Some(format!("{}", style().paint("~"))));
+        assert_eq!(get_actual(2, 2, 0), None); // offset same as shlvl; hide
+        assert_eq!(get_actual(2, 3, 0), None); // offset larger than shlvl; hide
+        assert_eq!(get_actual(2, 1, 3), None); // high threshold; hide
+                                               // threshold not high enough; hide
+        assert_eq!(get_actual(2, 1, 2), Some(format!("{}", style().paint("~"))));
+    }
 }