fix(task): support tasks without commands (#27191)

Support running tasks that have no command and only dependencies. This
is useful for when you want to group tasks only.

Cargo.toml

@@ -51,7 +51,7 @@ deno_ast = { version = "=0.44.0", features = ["transpiling"] }
 deno_core = { version = "0.326.0" }
 
 deno_bench_util = { version = "0.178.0", path = "./bench_util" }
-deno_config = { version = "=0.39.3", features = ["workspace", "sync"] }
+deno_config = { version = "=0.40.0", features = ["workspace", "sync"] }
 deno_lockfile = "=0.23.2"
 deno_media_type = { version = "0.2.0", features = ["module_specifier"] }
 deno_npm = "=0.26.0"

cli/lsp/language_server.rs

@@ -3793,7 +3793,7 @@ impl Inner {
         for (name, command) in scripts {
           result.push(TaskDefinition {
             name: name.clone(),
-            command: command.clone(),
+            command: Some(command.clone()),
             source_uri: url_to_uri(&package_json.specifier())
               .map_err(|_| LspError::internal_error())?,
           });

cli/lsp/lsp_custom.rs

@@ -14,7 +14,7 @@ pub const LATEST_DIAGNOSTIC_BATCH_INDEX: &str =
 #[serde(rename_all = "camelCase")]
 pub struct TaskDefinition {
   pub name: String,
-  pub command: String,
+  pub command: Option<String>,
   pub source_uri: lsp::Uri,
 }
 

cli/schemas/config-file.v1.json

@@ -446,7 +446,6 @@
                 },
                 "command": {
                   "type": "string",
-                  "required": true,
                   "description": "The task to execute"
                 },
                 "dependencies": {

cli/tools/task.rs

@@ -231,7 +231,7 @@ pub async fn execute_script(
           &Url::from_directory_path(cli_options.initial_cwd()).unwrap(),
           "",
           &TaskDefinition {
-            command: task_flags.task.as_ref().unwrap().to_string(),
+            command: Some(task_flags.task.as_ref().unwrap().to_string()),
             dependencies: vec![],
             description: None,
           },
@@ -448,6 +448,16 @@ impl<'a> TaskRunner<'a> {
     kill_signal: KillSignal,
     argv: &'a [String],
   ) -> Result<i32, deno_core::anyhow::Error> {
+    let Some(command) = &definition.command else {
+      log::info!(
+        "{} {} {}",
+        colors::green("Task"),
+        colors::cyan(task_name),
+        colors::gray("(no command)")
+      );
+      return Ok(0);
+    };
+
     if let Some(npm_resolver) = self.npm_resolver.as_managed() {
       npm_resolver.ensure_top_level_package_json_install().await?;
       npm_resolver
@@ -469,7 +479,7 @@ impl<'a> TaskRunner<'a> {
     self
       .run_single(RunSingleOptions {
         task_name,
-        script: &definition.command,
+        script: command,
         cwd: &cwd,
         custom_commands,
         kill_signal,
@@ -837,7 +847,7 @@ fn print_available_tasks(
           is_deno: false,
           name: name.to_string(),
           task: deno_config::deno_json::TaskDefinition {
-            command: script.to_string(),
+            command: Some(script.to_string()),
             dependencies: vec![],
             description: None,
           },
@@ -873,11 +883,13 @@ fn print_available_tasks(
         )?;
       }
     }
-    writeln!(
-      writer,
-      "    {}",
-      strip_ansi_codes_and_escape_control_chars(&desc.task.command)
-    )?;
+    if let Some(command) = &desc.task.command {
+      writeln!(
+        writer,
+        "    {}",
+        strip_ansi_codes_and_escape_control_chars(command)
+      )?;
+    };
     if !desc.task.dependencies.is_empty() {
       let dependencies = desc
         .task

tests/specs/task/dependencies/__test__.jsonc

@@ -61,6 +61,18 @@
       "cwd": "arg_task_with_deps",
       "args": "task a a",
       "output": "./arg_task_with_deps.out"
+    },
+    "no_command": {
+      "cwd": "no_command",
+      "args": "task a",
+      "output": "./no_command.out",
+      "exitCode": 0
+    },
+    "no_command_list": {
+      "cwd": "no_command",
+      "args": "task",
+      "output": "./no_command_list.out",
+      "exitCode": 0
     }
   }
 }

tests/specs/task/dependencies/no_command.out

@@ -0,0 +1,5 @@
+Task b echo 'b'
+b
+Task c echo 'c'
+c
+Task a (no command)

tests/specs/task/dependencies/no_command/deno.json

@@ -0,0 +1,13 @@
+{
+  "tasks": {
+    "a": {
+      "dependencies": ["b", "c"]
+    },
+    "b": {
+      "command": "echo 'b'"
+    },
+    "c": {
+      "command": "echo 'c'"
+    }
+  }
+}

tests/specs/task/dependencies/no_command_list.out

@@ -0,0 +1,7 @@
+Available tasks:
+- a
+    depends on: b, c
+- b
+    echo 'b'
+- c
+    echo 'c'