Improve TestPageFill comment

tests/element_handle_test.go

@@ -299,8 +299,7 @@ func TestElementHandleIsChecked(t *testing.T) {
 }
 
 func TestElementHandleQueryAll(t *testing.T) {
-	// tests are faster than parallel execution.
-	// do not make this test parallel.
+	t.Parallel()
 
 	const (
 		wantLiLen = 2
@@ -316,6 +315,8 @@ func TestElementHandleQueryAll(t *testing.T) {
   	`, nil)
 
 	t.Run("element_handle", func(t *testing.T) {
+		t.Parallel()
+
 		el, err := p.Query("#aul")
 		require.NoError(t, err)
 
@@ -325,12 +326,16 @@ func TestElementHandleQueryAll(t *testing.T) {
 		assert.Equal(t, wantLiLen, len(els))
 	})
 	t.Run("page", func(t *testing.T) {
+		t.Parallel()
+
 		els, err := p.QueryAll(query)
 		require.NoError(t, err)
 
 		assert.Equal(t, wantLiLen, len(els))
 	})
 	t.Run("frame", func(t *testing.T) {
+		t.Parallel()
+
 		els, err := p.MainFrame().QueryAll(query)
 		require.NoError(t, err)
 		assert.Equal(t, wantLiLen, len(els))

tests/page_test.go

@@ -350,17 +350,11 @@ func TestPageInputSpecialCharacters(t *testing.T) {
 }
 
 func TestPageFill(t *testing.T) {
-	// these tests are not parallel by intention because
-	// they're testing the same page instance and they're
-	// faster when run sequentially.
+	t.Parallel()
 
-	p := newTestBrowser(t).NewPage(nil)
-	p.SetContent(`
-		<input id="text" type="text" value="something" />
-		<input id="date" type="date" value="2012-03-12"/>
-		<input id="number" type="number" value="42"/>
-		<input id="unfillable" type="radio" />
-	`, nil)
+	// Subtests race with each other since they change the same page content.
+	// We could make each subtest to create and run their own browsers
+	// (and not share them), but that would make the test run 2X.
 
 	happy := []struct{ name, selector, value string }{
 		{name: "text", selector: "#text", value: "fill me up"},
@@ -373,13 +367,34 @@ func TestPageFill(t *testing.T) {
 		{name: "unfillable", selector: "#unfillable", value: "can't touch this"},
 	}
 	for _, tt := range happy {
+		tt := tt
 		t.Run("happy/"+tt.name, func(t *testing.T) {
+			t.Parallel()
+
+			p := newTestBrowser(t).NewPage(nil)
+			p.SetContent(`
+				<input id="text" type="text" value="something" />
+				<input id="date" type="date" value="2012-03-12"/>
+				<input id="number" type="number" value="42"/>
+				<input id="unfillable" type="radio" />
+			`, nil)
+
 			p.Fill(tt.selector, tt.value, nil)
 			require.Equal(t, tt.value, p.InputValue(tt.selector, nil))
 		})
 	}
 	for _, tt := range sad {
+		tt := tt
 		t.Run("sad/"+tt.name, func(t *testing.T) {
+			t.Parallel()
+
+			p := newTestBrowser(t).NewPage(nil)
+			p.SetContent(`
+				<input id="text" type="text" value="something" />
+				<input id="date" type="date" value="2012-03-12"/>
+				<input id="number" type="number" value="42"/>
+				<input id="unfillable" type="radio" />
+			`, nil)
 			require.Panics(t, func() { p.Fill(tt.selector, tt.value, nil) })
 		})
 	}