Add tests for GUI

gui/gui.go

@@ -16,7 +16,13 @@ import (
 
 const rootID = "root"
 
+type runner func(ctx context.Context, t terminalapi.Terminal, c *container.Container, opts ...termdash.Option) error
+
 func Run() error {
+	return run(termdash.Run)
+}
+
+func run(r runner) error {
 	ctx, cancel := context.WithCancel(context.Background())
 	defer cancel()
 
@@ -55,7 +61,7 @@ func Run() error {
 
 	k := keybinds(ctx, cancel, d)
 
-	return termdash.Run(ctx, t, c, termdash.KeyboardSubscriber(k), termdash.RedrawInterval(redrawInterval))
+	return r(ctx, t, c, termdash.KeyboardSubscriber(k), termdash.RedrawInterval(redrawInterval))
 }
 
 func gridLayout(w *widgets) ([]container.Option, error) {

gui/gui_test.go

@@ -0,0 +1,46 @@
+package gui
+
+import (
+	"context"
+	"fmt"
+	"testing"
+
+	"github.com/mum4k/termdash"
+	"github.com/mum4k/termdash/container"
+	"github.com/mum4k/termdash/terminal/terminalapi"
+	"github.com/stretchr/testify/assert"
+)
+
+// TODO: Ensure to kill all goroutine when running unit tests.
+/*func TestMain(m *testing.M) {
+	goleak.VerifyTestMain(m)
+}*/
+
+func TestRun(t *testing.T) {
+	tests := []struct {
+		name    string
+		r       runner
+		wantErr bool
+	}{
+		{
+			name: "successful running",
+			r: func(context.Context, terminalapi.Terminal, *container.Container, ...termdash.Option) error {
+				return nil
+			},
+			wantErr: false,
+		},
+		{
+			name: "failed running",
+			r: func(context.Context, terminalapi.Terminal, *container.Container, ...termdash.Option) error {
+				return fmt.Errorf("error")
+			},
+			wantErr: true,
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			err := run(tt.r)
+			assert.Equal(t, tt.wantErr, err != nil)
+		})
+	}
+}