fix: include flatten with a default task

task_test.go

@@ -1240,6 +1240,8 @@ func TestIncludesFlatten(t *testing.T) {
 		expectedOutput string
 	}{
 		{name: "included flatten", taskfile: "Taskfile.yml", task: "gen", expectedOutput: "gen from included\n"},
+		{name: "included flatten with default", taskfile: "Taskfile.yml", task: "default", expectedOutput: "default from included flatten\n"},
+		{name: "included flatten can call entrypoint tasks", taskfile: "Taskfile.yml", task: "from_entrypoint", expectedOutput: "from entrypoint\n"},
 		{name: "included flatten with deps", taskfile: "Taskfile.yml", task: "with_deps", expectedOutput: "gen from included\nwith_deps from included\n"},
 		{name: "included flatten nested", taskfile: "Taskfile.yml", task: "from_nested", expectedOutput: "from nested\n"},
 		{name: "included flatten multiple same task", taskfile: "Taskfile.multiple.yml", task: "gen", expectedErr: true, expectedOutput: "task: Found multiple tasks (gen) included by \"included\"\""},

taskfile/ast/tasks.go

@@ -112,12 +112,12 @@ func (t1 *Tasks) Merge(t2 Tasks, include *Include, includedTaskfileVars *Vars) e
 		return nil
 	})
 
-	// If the included Taskfile has a default task and the parent namespace has
+	// If the included Taskfile has a default task, being not flattened and the parent namespace has
 	// no task with a matching name, we can add an alias so that the user can
 	// run the included Taskfile's default task without specifying its full
 	// name. If the parent namespace has aliases, we add another alias for each
 	// of them.
-	if t2.Get("default") != nil && t1.Get(include.Namespace) == nil {
+	if t2.Get("default") != nil && t1.Get(include.Namespace) == nil && !include.Flatten {
 		defaultTaskName := fmt.Sprintf("%s:default", include.Namespace)
 		t1.Get(defaultTaskName).Aliases = append(t1.Get(defaultTaskName).Aliases, include.Namespace)
 		t1.Get(defaultTaskName).Aliases = slices.Concat(t1.Get(defaultTaskName).Aliases, include.Aliases)

testdata/includes_flatten/Taskfile.with_default.yml

@@ -0,0 +1,3 @@
+version: '3'
+tasks:
+  default: echo "default from included flatten"

testdata/includes_flatten/Taskfile.yml

@@ -5,9 +5,11 @@ includes:
     taskfile: ./included
     dir: ./included
     flatten: true
+  with_default:
+    taskfile: ./Taskfile.with_default.yml
+    flatten: true
 
 tasks:
-  default:
-    cmds:
-      - echo root_directory > root_directory.txt
+  from_entrypoint: echo "from entrypoint"
+