feat(config): add shell to watch_files run

docs/hooks.md

@@ -110,7 +110,19 @@ patterns = ["src/**/*.rs"]
 run = "cargo fmt"
 ```
 
-You can also reference a mise task instead of an inline script:
+By default, `run` uses the configured inline shell:
+[`unix_default_inline_shell_args`](/configuration/settings.html#unix_default_inline_shell_args)
+or [`windows_default_inline_shell_args`](/configuration/settings.html#windows_default_inline_shell_args).
+Add `shell = "bash -c"` to choose a different inline shell command for a watch file hook:
+
+```toml
+[[watch_files]]
+patterns = ["*.js"]
+run = "eslint --fix ."
+shell = "bash -c"
+```
+
+`shell` only applies to `run` hooks. You can also reference a mise task instead of an inline script:
 
 ```toml
 [[watch_files]]

e2e/config/test_schema_tombi

@@ -39,6 +39,11 @@ cat >"$HOME/workdir/mise.toml" <<'TOML'
 env_file = ".env"
 env_path = "./bin"
 
+[[watch_files]]
+patterns = ["src/**/*.rs"]
+run = "cargo fmt"
+shell = "bash -c"
+
 [task_templates.base]
 quiet = true
 dir = "{{config_root}}"
@@ -119,7 +124,7 @@ strict = true
 
 [[schemas]]
 path = "file://$SCHEMA_PATH"
-include = ["mise-bad.toml", "mise-bad-age.toml", "mise-bad-env-directive.toml", "mise-bad-tmpl.toml", "mise-bad-os.toml"]
+include = ["mise-bad.toml", "mise-bad-age.toml", "mise-bad-env-directive.toml", "mise-bad-tmpl.toml", "mise-bad-os.toml", "mise-bad-watch-files.toml"]
 
 [[schemas]]
 path = "file://$TASK_SCHEMA_PATH"
@@ -160,6 +165,15 @@ TOML
 
 assert_fail "$TOMBI_LINT mise-bad-os.toml"
 
+cat >"$HOME/workdir/mise-bad-watch-files.toml" <<'TOML'
+[[watch_files]]
+patterns = ["uv.lock"]
+task = "sync-deps"
+shell = "bash -c"
+TOML
+
+assert_fail "$TOMBI_LINT mise-bad-watch-files.toml"
+
 cat >"$HOME/workdir/mise-bad-task-os.toml" <<'TOML'
 [build]
 run = "echo ok"

e2e/config/test_watch_files_shell

@@ -0,0 +1,49 @@
+#!/usr/bin/env bash
+
+cat >"$HOME/watch-fallback-shell" <<'SCRIPT'
+#!/usr/bin/env bash
+if [[ $1 != "-c" ]]; then
+  exit 99
+fi
+echo WATCH_FALLBACK_SHELL
+exec bash -c "$2"
+SCRIPT
+chmod +x "$HOME/watch-fallback-shell"
+
+cat >"$HOME/watch-explicit-shell" <<'SCRIPT'
+#!/usr/bin/env bash
+if [[ $1 != "-c" ]]; then
+  exit 99
+fi
+echo WATCH_EXPLICIT_SHELL
+exec bash -c "$2"
+SCRIPT
+chmod +x "$HOME/watch-explicit-shell"
+
+cat <<EOF >mise.toml
+[settings]
+unix_default_inline_shell_args = "$HOME/watch-fallback-shell -c"
+
+[[watch_files]]
+patterns = ["fallback.txt"]
+run = "echo WATCH_FALLBACK_RUN"
+
+[[watch_files]]
+patterns = ["explicit.txt"]
+run = "echo WATCH_EXPLICIT_RUN"
+shell = "$HOME/watch-explicit-shell -c"
+EOF
+
+touch fallback.txt explicit.txt
+eval "$(mise hook-env)"
+
+sleep 1
+printf "changed" >>fallback.txt
+printf "changed" >>explicit.txt
+
+mise hook-env >hook-env.out 2>&1
+
+assert_contains "cat hook-env.out" "WATCH_FALLBACK_SHELL"
+assert_contains "cat hook-env.out" "WATCH_FALLBACK_RUN"
+assert_contains "cat hook-env.out" "WATCH_EXPLICIT_SHELL"
+assert_contains "cat hook-env.out" "WATCH_EXPLICIT_RUN"

schema/mise.json

@@ -2127,29 +2127,43 @@
       "items": {
         "type": "object",
         "description": "file to watch for changes",
-        "unevaluatedProperties": false,
-        "properties": {
-          "run": {
-            "type": "string",
-            "description": "script to run when file changes"
-          },
-          "task": {
-            "type": "string",
-            "description": "mise task to run when file changes"
-          },
-          "patterns": {
-            "type": "array",
-            "description": "patterns to watch for",
-            "items": {
-              "type": "string"
-            }
-          }
-        },
         "oneOf": [
           {
+            "unevaluatedProperties": false,
+            "properties": {
+              "run": {
+                "type": "string",
+                "description": "script to run when file changes"
+              },
+              "shell": {
+                "type": "string",
+                "description": "inline shell command used to run script when file changes"
+              },
+              "patterns": {
+                "type": "array",
+                "description": "patterns to watch for",
+                "items": {
+                  "type": "string"
+                }
+              }
+            },
             "required": ["run"]
           },
           {
+            "unevaluatedProperties": false,
+            "properties": {
+              "task": {
+                "type": "string",
+                "description": "mise task to run when file changes"
+              },
+              "patterns": {
+                "type": "array",
+                "description": "patterns to watch for",
+                "items": {
+                  "type": "string"
+                }
+              }
+            },
             "required": ["task"]
           }
         ]

src/config/config_file/mise_toml.rs

@@ -945,6 +945,11 @@ impl ConfigFile for MiseToml {
                         .as_ref()
                         .map(|r| self.parse_template(r))
                         .transpose()?,
+                    shell: wf
+                        .shell
+                        .as_ref()
+                        .map(|s| self.parse_template(s))
+                        .transpose()?,
                     task: wf
                         .task
                         .as_ref()

src/watch_files.rs

@@ -17,6 +17,8 @@ pub struct WatchFile {
     pub patterns: Vec<String>,
     #[serde(default)]
     pub run: Option<String>,
+    #[serde(default)]
+    pub shell: Option<String>,
     pub task: Option<String>,
 }
 
@@ -45,10 +47,13 @@ pub async fn execute_runs(config: &Arc<Config>, ts: &Toolset) {
                 if wf.task.is_some() && wf.run.is_some() {
                     warn!("watch_file hook has both run and task set, using task");
                 }
+                if wf.task.is_some() && wf.shell.is_some() {
+                    warn!("watch_file hook has both shell and task set, ignoring shell");
+                }
                 let result = if let Some(task_name) = &wf.task {
                     execute_task(config, ts, &root, task_name, files).await
                 } else if let Some(run) = &wf.run {
-                    execute(config, ts, &root, run, files).await
+                    execute(config, ts, &root, run, wf.shell.as_deref(), files).await
                 } else {
                     warn!("watch_file hook has neither run nor task set, skipping");
                     continue;
@@ -69,18 +74,26 @@ async fn execute(
     ts: &Toolset,
     root: &Path,
     run: &str,
+    shell: Option<&str>,
     files: Vec<&PathBuf>,
 ) -> Result<()> {
     Settings::get().ensure_experimental("watch_file_hooks")?;
     let modified_files_var = files
         .iter()
         .map(|f| f.to_string_lossy().replace(':', "\\:"))
         .join(":");
-    let shell = Settings::get().default_inline_shell()?;
+    let shell = match shell {
+        Some(shell) => shell_words::split(shell)?,
+        None => Settings::get().default_inline_shell()?,
+    };
+    let (program, shell_args) = shell.split_first().ok_or_else(|| {
+        eyre::eyre!(
+            "inline shell is empty; check watch_files.shell or unix_default_inline_shell_args / windows_default_inline_shell_args"
+        )
+    })?;
 
-    let args = shell
+    let args = shell_args
         .iter()
-        .skip(1)
         .map(|s| s.as_str())
         .chain(once(run))
         .collect_vec();
@@ -98,7 +111,7 @@ async fn execute(
     );
     // TODO: this should be different but I don't have easy access to it
     // env.insert("MISE_CONFIG_ROOT".to_string(), root.to_string_lossy().to_string());
-    cmd(&shell[0], args)
+    cmd(program, args)
         .stdout_to_stderr()
         // .dir(root)
         .full_env(env)