Perf(purescript): Lazy eval purescript (#2191)

* perf(purescript): evaluate version lazily

* fix(purescript): update format string; update tests

Co-authored-by: Moritz Vetter <mv@3yourmind.com>

3 files changed, 13 insertions, 12 deletions

diff --git a/docs/config/README.md b/docs/config/README.md
index 78f05d8f3..030ad77df 100644
--- a/docs/config/README.md
+++ b/docs/config/README.md
@@ -2000,12 +2000,12 @@ The module will be shown if any of the following conditions are met:
 
 ### Options
 
-| Option     | Default                            | Description                                                  |
-| ---------- | ---------------------------------- | ------------------------------------------------------------ |
-| `format`   | `"via [$symbol$version]($style) "` | The format for the module.                                   |
-| `symbol`   | `"<=> "`                           | The symbol used before displaying the version of PureScript. |
-| `style`    | `"bold white"`                     | The style for the module.                                    |
-| `disabled` | `false`                            | Disables the `purescript` module.                            |
+| Option     | Default                              | Description                                                  |
+| ---------- | ------------------------------------ | ------------------------------------------------------------ |
+| `format`   | `"via [$symbol($version )]($style)"` | The format for the module.                                   |
+| `symbol`   | `"<=> "`                             | The symbol used before displaying the version of PureScript. |
+| `style`    | `"bold white"`                       | The style for the module.                                    |
+| `disabled` | `false`                              | Disables the `purescript` module.                            |
 
 ### Variables
 
diff --git a/src/configs/purescript.rs b/src/configs/purescript.rs
index 4dc01b3d4..2696610b0 100644
--- a/src/configs/purescript.rs
+++ b/src/configs/purescript.rs
@@ -13,7 +13,7 @@ pub struct PureScriptConfig<'a> {
 impl<'a> RootModuleConfig<'a> for PureScriptConfig<'a> {
     fn new() -> Self {
         PureScriptConfig {
-            format: "via [$symbol$version]($style) ",
+            format: "via [$symbol($version )]($style)",
             symbol: "<=> ",
             style: "bold white",
             disabled: false,
diff --git a/src/modules/purescript.rs b/src/modules/purescript.rs
index 49dabc588..96d189bbd 100644
--- a/src/modules/purescript.rs
+++ b/src/modules/purescript.rs
@@ -20,8 +20,6 @@ pub fn module<'a>(context: &'a Context) -> Option<Module<'a>> {
         return None;
     }
 
-    let purs_version = utils::exec_cmd("purs", &["--version"])?.stdout;
-
     let mut module = context.new_module("purescript");
     let config: PureScriptConfig = PureScriptConfig::try_load(module.config);
 
@@ -36,7 +34,10 @@ pub fn module<'a>(context: &'a Context) -> Option<Module<'a>> {
                 _ => None,
             })
             .map(|variable| match variable {
-                "version" => Some(Ok(format!("v{}", purs_version.trim()))),
+                "version" => {
+                    let purs_version = utils::exec_cmd("purs", &["--version"])?.stdout;
+                    Some(Ok(format!("v{}", purs_version.trim())))
+                }
                 _ => None,
             })
             .parse(None)
@@ -75,7 +76,7 @@ mod tests {
         File::create(dir.path().join("Main.purs"))?.sync_all()?;
 
         let actual = ModuleRenderer::new("purescript").path(dir.path()).collect();
-        let expected = Some(format!("via {} ", Color::White.bold().paint("<=> v0.13.5")));
+        let expected = Some(format!("via {}", Color::White.bold().paint("<=> v0.13.5 ")));
         assert_eq!(expected, actual);
         dir.close()
     }
@@ -86,7 +87,7 @@ mod tests {
         File::create(dir.path().join("spago.dhall"))?.sync_all()?;
 
         let actual = ModuleRenderer::new("purescript").path(dir.path()).collect();
-        let expected = Some(format!("via {} ", Color::White.bold().paint("<=> v0.13.5")));
+        let expected = Some(format!("via {}", Color::White.bold().paint("<=> v0.13.5 ")));
         assert_eq!(expected, actual);
         dir.close()
     }