Respect RequireCLI option for explicit manager selection

detector.go

@@ -52,7 +52,7 @@ func (d *Detector) sortDefinitions() {
 
 func (d *Detector) Detect(dir string, opts DetectOptions) (Manager, error) {
 	if opts.Manager != "" {
-		return d.detectExplicit(dir, opts.Manager)
+		return d.detectExplicit(dir, opts.Manager, opts.RequireCLI)
 	}
 
 	files, err := os.ReadDir(dir)
@@ -100,10 +100,10 @@ func (d *Detector) Detect(dir string, opts DetectOptions) (Manager, error) {
 	return nil, ErrNoManifest{Dir: dir}
 }
 
-func (d *Detector) detectExplicit(dir, managerName string) (Manager, error) {
+func (d *Detector) detectExplicit(dir, managerName string, requireCLI bool) (Manager, error) {
 	for _, def := range d.definitions {
 		if def.Name == managerName {
-			return d.buildManager(def, dir, nil, true)
+			return d.buildManager(def, dir, nil, requireCLI)
 		}
 	}
 	return nil, ErrNoManifest{Dir: dir}

detector_test.go

@@ -0,0 +1,54 @@
+package managers
+
+import (
+	"testing"
+
+	"github.com/git-pkgs/managers/definitions"
+)
+
+func TestDetectExplicit_RequireCLI(t *testing.T) {
+	translator := NewTranslator()
+	runner := NewMockRunner()
+	detector := NewDetector(translator, runner)
+
+	def := &definitions.Definition{
+		Name:   "fakepkg",
+		Binary: "binary-that-does-not-exist",
+	}
+	detector.Register(def)
+
+	t.Run("require CLI fails when binary missing", func(t *testing.T) {
+		_, err := detector.Detect("/tmp", DetectOptions{
+			Manager:    "fakepkg",
+			RequireCLI: true,
+		})
+		if err == nil {
+			t.Fatal("expected error when binary not found")
+		}
+		var cliErr ErrCLINotFound
+		if !isErrCLINotFound(err, &cliErr) {
+			t.Fatalf("expected ErrCLINotFound, got: %v", err)
+		}
+	})
+
+	t.Run("no CLI required succeeds without binary", func(t *testing.T) {
+		mgr, err := detector.Detect("/tmp", DetectOptions{
+			Manager:    "fakepkg",
+			RequireCLI: false,
+		})
+		if err != nil {
+			t.Fatalf("unexpected error: %v", err)
+		}
+		if mgr == nil {
+			t.Fatal("expected manager, got nil")
+		}
+	})
+}
+
+func isErrCLINotFound(err error, target *ErrCLINotFound) bool {
+	e, ok := err.(ErrCLINotFound)
+	if ok {
+		*target = e
+	}
+	return ok
+}