change Run to allow many actions

This can simplify some common use cases, like running a few actions
directly, or running no actions at all. It's also an almost entirely
backwards compatible change, as all Run call sites should continue to
compile and work.

Leave Tasks, as it can still be useful for functions to return complex
sequences of actions as a single Action.

allocate_test.go

@@ -20,10 +20,10 @@ func TestExecAllocator(t *testing.T) {
 
 	want := "insert"
 	var got string
-	if err := Run(taskCtx, Tasks{
-		Navigate(testdataDir + "/form.html"),
+	if err := Run(taskCtx,
+		Navigate(testdataDir+"/form.html"),
 		Text("#foo", &got, ByID),
-	}); err != nil {
+	); err != nil {
 		t.Fatal(err)
 	}
 	if got != want {
@@ -52,7 +52,7 @@ func TestExecAllocatorCancelParent(t *testing.T) {
 	// processes and browsers.
 
 	taskCtx, _ := NewContext(poolCtx)
-	if err := Run(taskCtx, Tasks{}); err != nil {
+	if err := Run(taskCtx); err != nil {
 		t.Fatal(err)
 	}
 

context.go

@@ -60,7 +60,7 @@ func FromContext(ctx context.Context) *Context {
 // Run runs an action against the provided context. The provided context must
 // contain a valid Allocator; typically, that will be created via NewContext or
 // NewAllocator.
-func Run(ctx context.Context, action Action) error {
+func Run(ctx context.Context, actions ...Action) error {
 	c := FromContext(ctx)
 	if c == nil || c.Allocator == nil {
 		return ErrInvalidContext
@@ -77,7 +77,7 @@ func Run(ctx context.Context, action Action) error {
 			return err
 		}
 	}
-	return action.Do(ctx, c.Target)
+	return Tasks(actions).Do(ctx, c.Target)
 }
 
 func (c *Context) newSession(ctx context.Context) error {

example_test.go

@@ -16,11 +16,11 @@ func ExampleTitle() {
 	defer cancel()
 
 	var title string
-	if err := chromedp.Run(ctx, chromedp.Tasks{
+	if err := chromedp.Run(ctx,
 		chromedp.Navigate("https://github.com/chromedp/chromedp/issues"),
 		chromedp.WaitVisible("#start-of-content", chromedp.ByID),
 		chromedp.Title(&title),
-	}); err != nil {
+	); err != nil {
 		panic(err)
 	}
 
@@ -57,7 +57,7 @@ func ExampleExecAllocatorOption() {
 	defer cancel()
 
 	// ensure that the browser process is started
-	if err := chromedp.Run(taskCtx, chromedp.Tasks{}); err != nil {
+	if err := chromedp.Run(taskCtx); err != nil {
 		panic(err)
 	}
 
@@ -83,7 +83,7 @@ func ExampleManyTabs() {
 	defer cancel()
 
 	// ensure the first tab is created
-	if err := chromedp.Run(ctx1, chromedp.Tasks{}); err != nil {
+	if err := chromedp.Run(ctx1); err != nil {
 		panic(err)
 	}
 
@@ -91,7 +91,7 @@ func ExampleManyTabs() {
 	ctx2, _ := chromedp.NewContext(ctx1)
 
 	// ensure the second tab is created
-	if err := chromedp.Run(ctx2, chromedp.Tasks{}); err != nil {
+	if err := chromedp.Run(ctx2); err != nil {
 		panic(err)
 	}
 

nav_test.go

@@ -73,11 +73,11 @@ func TestNavigationEntries(t *testing.T) {
 
 	expIdx, expEntries := 1, 2
 	for i, test := range tests {
-		if err := Run(ctx, Tasks{
-			Navigate(testdataDir + "/" + test.file),
+		if err := Run(ctx,
+			Navigate(testdataDir+"/"+test.file),
 			WaitVisible(test.waitID, ByID),
 			NavigationEntries(&index, &entries),
-		}); err != nil {
+		); err != nil {
 			t.Fatal(err)
 		}
 		if len(entries) != expEntries {
@@ -100,22 +100,22 @@ func TestNavigateToHistoryEntry(t *testing.T) {
 
 	var entries []*page.NavigationEntry
 	var index int64
-	if err := Run(ctx, Tasks{
+	if err := Run(ctx,
 		WaitVisible(`#icon-brankas`, ByID), // for image.html
 		NavigationEntries(&index, &entries),
 
-		Navigate(testdataDir + "/form.html"),
+		Navigate(testdataDir+"/form.html"),
 		WaitVisible(`#form`, ByID), // for form.html
-	}); err != nil {
+	); err != nil {
 		t.Fatal(err)
 	}
 
 	var title string
-	if err := Run(ctx, Tasks{
+	if err := Run(ctx,
 		NavigateToHistoryEntry(entries[index].ID),
 		WaitVisible(`#icon-brankas`, ByID), // for image.html
 		Title(&title),
-	}); err != nil {
+	); err != nil {
 		t.Fatal(err)
 	}
 	if title != entries[index].Title {
@@ -130,17 +130,17 @@ func TestNavigateBack(t *testing.T) {
 	defer cancel()
 
 	var title, exptitle string
-	if err := Run(ctx, Tasks{
+	if err := Run(ctx,
 		WaitVisible(`#form`, ByID), // for form.html
 		Title(&exptitle),
 
-		Navigate(testdataDir + "/image.html"),
+		Navigate(testdataDir+"/image.html"),
 		WaitVisible(`#icon-brankas`, ByID), // for image.html
 
 		NavigateBack(),
 		WaitVisible(`#form`, ByID), // for form.html
 		Title(&title),
-	}); err != nil {
+	); err != nil {
 		t.Fatal(err)
 	}
 
@@ -156,10 +156,10 @@ func TestNavigateForward(t *testing.T) {
 	defer cancel()
 
 	var title, exptitle string
-	if err := Run(ctx, Tasks{
+	if err := Run(ctx,
 		WaitVisible(`#form`, ByID), // for form.html
 
-		Navigate(testdataDir + "/image.html"),
+		Navigate(testdataDir+"/image.html"),
 		WaitVisible(`#icon-brankas`, ByID), // for image.html
 		Title(&exptitle),
 
@@ -169,7 +169,7 @@ func TestNavigateForward(t *testing.T) {
 		NavigateForward(),
 		WaitVisible(`#icon-brankas`, ByID), // for image.html
 		Title(&title),
-	}); err != nil {
+	); err != nil {
 		t.Fatal(err)
 	}
 
@@ -211,7 +211,7 @@ func TestReload(t *testing.T) {
 	defer cancel()
 
 	var title, exptitle string
-	if err := Run(ctx, Tasks{
+	if err := Run(ctx,
 		Navigate(s.URL),
 		WaitReady(`#count0`, ByID),
 		Title(&exptitle),
@@ -219,7 +219,7 @@ func TestReload(t *testing.T) {
 		Reload(),
 		WaitReady(`#count1`, ByID),
 		Title(&title),
-	}); err != nil {
+	); err != nil {
 		t.Fatal(err)
 	}
 
@@ -237,11 +237,11 @@ func TestCaptureScreenshot(t *testing.T) {
 	// set the viewport size, to know what screenshot size to expect
 	width, height := 650, 450
 	var buf []byte
-	if err := Run(ctx, Tasks{
+	if err := Run(ctx,
 		emulation.SetDeviceMetricsOverride(int64(width), int64(height), 1.0, false),
 		WaitVisible(`#icon-brankas`, ByID), // for image.html
 		CaptureScreenshot(&buf),
-	}); err != nil {
+	); err != nil {
 		t.Fatal(err)
 	}
 
@@ -315,10 +315,10 @@ func TestLocation(t *testing.T) {
 	defer cancel()
 
 	var urlstr string
-	if err := Run(ctx, Tasks{
+	if err := Run(ctx,
 		WaitVisible(`#form`, ByID), // for form.html
 		Location(&urlstr),
-	}); err != nil {
+	); err != nil {
 		t.Fatal(err)
 	}
 
@@ -334,10 +334,10 @@ func TestTitle(t *testing.T) {
 	defer cancel()
 
 	var title string
-	if err := Run(ctx, Tasks{
+	if err := Run(ctx,
 		WaitVisible(`#icon-brankas`, ByID), // for image.html
 		Title(&title),
-	}); err != nil {
+	); err != nil {
 		t.Fatal(err)
 	}
 

query_test.go

@@ -994,12 +994,12 @@ func TestFileUpload(t *testing.T) {
 			defer cancel()
 
 			var result string
-			if err := Run(ctx, Tasks{
+			if err := Run(ctx,
 				Navigate(s.URL),
 				test.a,
 				Click(`input[name="submit"]`),
 				Text(`#result`, &result, ByID, NodeVisible),
-			}); err != nil {
+			); err != nil {
 				t.Fatalf("test %d expected no error, got: %v", i, err)
 			}