Adjust when_changed to work with imported tasks.

internal/hash/hash.go

@@ -20,5 +20,5 @@ func Name(t *ast.Task) (string, error) {
 
 func Hash(t *ast.Task) (string, error) {
 	h, err := hashstructure.Hash(t, hashstructure.FormatV2, nil)
-	return fmt.Sprintf("%s:%d", t.Task, h), err
+	return fmt.Sprintf("%s:%s:%d", t.Location.Taskfile, t.LocalName(), h), err
 }

task_test.go

@@ -1851,6 +1851,29 @@ func TestRunOnceSharedDeps(t *testing.T) {
 	assert.Contains(t, buff.String(), `task: [service-b:build] echo "build b"`)
 }
 
+func TestRunWhenChanged(t *testing.T) {
+	t.Parallel()
+
+	const dir = "testdata/run_when_changed"
+
+	var buff bytes.Buffer
+	e := task.NewExecutor(
+		task.WithDir(dir),
+		task.WithStdout(&buff),
+		task.WithStderr(&buff),
+		task.WithForceAll(true),
+		task.WithSilent(true),
+	)
+	require.NoError(t, e.Setup())
+	require.NoError(t, e.Run(t.Context(), &task.Call{Task: "start"}))
+	expectedOutputOrder := strings.TrimSpace(`
+login server=fubar user=fubar
+login server=foo user=foo
+login server=bar user=bar
+`)
+	assert.Contains(t, buff.String(), expectedOutputOrder)
+}
+
 func TestDeferredCmds(t *testing.T) {
 	t.Parallel()
 

taskfile/ast/task.go

@@ -13,7 +13,7 @@ import (
 
 // Task represents a task
 type Task struct {
-	Task          string
+	Task          string `hash:"ignore"`
 	Cmds          []*Cmd
 	Deps          []*Dep
 	Label         string
@@ -36,18 +36,18 @@ type Task struct {
 	Interactive   bool
 	Internal      bool
 	Method        string
-	Prefix        string
+	Prefix        string `hash:"ignore"`
 	IgnoreError   bool
 	Run           string
 	Platforms     []*Platform
 	Watch         bool
 	Location      *Location
 	// Populated during merging
-	Namespace            string
+	Namespace            string `hash:"ignore"`
 	IncludeVars          *Vars
 	IncludedTaskfileVars *Vars
 
-	FullName string
+	FullName string `hash:"ignore"`
 }
 
 func (t *Task) Name() string {

testdata/run_when_changed/Taskfile.yml

@@ -0,0 +1,11 @@
+version: '3'
+
+includes:
+  service-a: ./service-a
+  service-b: ./service-b
+
+tasks:
+  start:
+    cmds:
+      - task: service-a:start
+      - task: service-b:start

testdata/run_when_changed/library/Taskfile.yml

@@ -0,0 +1,7 @@
+version: '3'
+
+tasks:
+  login:
+    run: when_changed
+    cmds:
+      - echo "login server={{.SERVER}} user={{.USER}}"

testdata/run_when_changed/service-a/Taskfile.yml

@@ -0,0 +1,18 @@
+version: '3'
+
+includes:
+  library:
+    taskfile: ../library/Taskfile.yml
+    dir: ../library
+
+tasks:
+  start:
+    cmds:
+      - task: library:login
+        vars:
+          SERVER: fubar
+          USER: fubar
+      - task: library:login
+        vars:
+          SERVER: foo
+          USER: foo

testdata/run_when_changed/service-b/Taskfile.yml

@@ -0,0 +1,18 @@
+version: '3'
+
+includes:
+  library:
+    taskfile: ../library/Taskfile.yml
+    dir: ../library
+
+tasks:
+  start:
+    cmds:
+      - task: library:login
+        vars:
+          SERVER: fubar
+          USER: fubar
+      - task: library:login
+        vars:
+          SERVER: bar
+          USER: bar