fix(task): don't panic with filter on missing task argument

cli/tools/task.rs

@@ -78,14 +78,6 @@ pub async fn execute_script(
   let packages_task_configs: Vec<PackageTaskInfo> = if let Some(filter) =
     &task_flags.filter
   {
-    let task_name = task_flags.task.as_ref().unwrap();
-
-    // Filter based on package name
-    let package_regex = arg_to_regex(filter)?;
-    let task_regex = arg_to_regex(task_name)?;
-
-    let mut packages_task_info: Vec<PackageTaskInfo> = vec![];
-
     fn matches_package(
       config: &FolderConfigs,
       force_use_pkg_json: bool,
@@ -112,7 +104,55 @@ pub async fn execute_script(
       false
     }
 
+    // Filter based on package name
+    let package_regex = arg_to_regex(filter)?;
     let workspace = cli_options.workspace();
+
+    let Some(task_name) = &task_flags.task else {
+      let mut matched = false;
+      for folder in workspace.config_folders() {
+        if !matches_package(folder.1, force_use_pkg_json, &package_regex) {
+          continue;
+        }
+        matched = true;
+
+        let member_dir = workspace.resolve_member_dir(folder.0);
+        let mut tasks_config = member_dir.to_tasks_config()?;
+
+        let mut pkg_name = folder
+          .1
+          .deno_json
+          .as_ref()
+          .and_then(|deno| deno.json.name.clone())
+          .or(folder.1.pkg_json.as_ref().and_then(|pkg| pkg.name.clone()));
+
+        if force_use_pkg_json {
+          tasks_config = tasks_config.with_only_pkg_json();
+          pkg_name =
+            folder.1.pkg_json.as_ref().and_then(|pkg| pkg.name.clone());
+        }
+
+        print_available_tasks(
+          &mut std::io::stdout(),
+          &cli_options.start_dir,
+          &tasks_config,
+          pkg_name,
+        )?;
+      }
+
+      if !matched {
+        log::warn!(
+          "{}",
+          colors::red(format!("No package name matched the filter '{}' in available 'deno.json' or 'package.json' files.", filter))
+        );
+      }
+
+      return Ok(0);
+    };
+
+    let task_regex = arg_to_regex(task_name)?;
+    let mut packages_task_info: Vec<PackageTaskInfo> = vec![];
+
     for folder in workspace.config_folders() {
       if !matches_package(folder.1, force_use_pkg_json, &package_regex) {
         continue;
@@ -198,6 +238,7 @@ pub async fn execute_script(
         &mut std::io::stdout(),
         &cli_options.start_dir,
         &tasks_config,
+        None,
       )?;
       return Ok(0);
     };
@@ -310,6 +351,7 @@ impl<'a> TaskRunner<'a> {
       &mut std::io::stderr(),
       &self.cli_options.start_dir,
       tasks_config,
+      None,
     )
   }
 
@@ -662,8 +704,15 @@ fn print_available_tasks(
   writer: &mut dyn std::io::Write,
   workspace_dir: &Arc<WorkspaceDirectory>,
   tasks_config: &WorkspaceTasksConfig,
+  pkg_name: Option<String>,
 ) -> Result<(), std::io::Error> {
-  writeln!(writer, "{}", colors::green("Available tasks:"))?;
+  let heading = if let Some(s) = pkg_name {
+    format!("Available tasks ({}):", colors::cyan(s))
+  } else {
+    "Available tasks:".to_string()
+  };
+
+  writeln!(writer, "{}", colors::green(heading))?;
   let is_cwd_root_dir = tasks_config.root.is_none();
 
   if tasks_config.is_empty() {

tests/specs/task/filter/__test__.jsonc

@@ -30,6 +30,16 @@
       "args": "task --filter @foo/* dev",
       "output": "npm_workspace_order.out"
     },
+    "npm_filter_no_match_no_task": {
+      "cwd": "./npm",
+      "args": "task --filter @asdf",
+      "output": "npm_filter_no_match_no_task.out"
+    },
+    "npm_filter_no_task": {
+      "cwd": "./npm",
+      "args": "task --filter *",
+      "output": "npm_filter_no_task.out"
+    },
     "deno_all": {
       "cwd": "./deno",
       "args": "task --filter * dev",
@@ -54,6 +64,16 @@
       "cwd": "./deno_workspace_order",
       "args": "task --filter @foo/* dev",
       "output": "deno_workspace_order.out"
+    },
+    "deno_filter_no_match_no_task": {
+      "cwd": "./deno",
+      "args": "task --filter @asdf",
+      "output": "deno_filter_no_match_no_task.out"
+    },
+    "deno_filter_no_task": {
+      "cwd": "./deno",
+      "args": "task --filter *",
+      "output": "deno_filter_no_task.out"
     }
   }
 }

tests/specs/task/filter/deno_filter_no_match_no_task.out

@@ -0,0 +1 @@
+No package name matched the filter '@asdf' in available 'deno.json' or 'package.json' files.

tests/specs/task/filter/deno_filter_no_task.out

@@ -0,0 +1,6 @@
+Available tasks (@deno/bar):
+- dev
+    echo '@deno/bar'
+Available tasks (@deno/foo):
+- dev
+    echo '@deno/foo'

tests/specs/task/filter/npm_filter_no_match_no_task.out

@@ -0,0 +1 @@
+No package name matched the filter '@asdf' in available 'deno.json' or 'package.json' files.

tests/specs/task/filter/npm_filter_no_task.out

@@ -0,0 +1,6 @@
+Available tasks (bar):
+- dev (package.json)
+    echo 'bar'
+Available tasks (foo):
+- dev (package.json)
+    echo 'foo'