simplify the code ScrollScreenshot

must.go

@@ -387,9 +387,9 @@ func (p *Page) MustScreenshotFullPage(toFile ...string) []byte {
 	return bin
 }
 
-// MustScrollScreenshotPage is similar to [Page.ScrollScreenshot].
+// MustScrollScreenshot is similar to [Page.ScrollScreenshot].
 // If the toFile is "", it Page.will save output to "tmp/screenshots" folder, time as the file name.
-func (p *Page) MustScrollScreenshotPage(toFile ...string) []byte {
+func (p *Page) MustScrollScreenshot(toFile ...string) []byte {
 	bin, err := p.ScrollScreenshot(nil)
 	p.e(err)
 	p.e(saveFile(saveFileTypeScreenshot, bin, toFile))

page.go

@@ -489,7 +489,7 @@ type ScrollScreenshotOptions struct {
 // but achieves it by scrolling and capturing screenshots in a loop, and then stitching them together.
 // Note that this method also has a flaw: when there are elements with fixed
 // positioning on the page (usually header navigation components),
-// these elements will appear repeatedly,	you can set the FixedTop parameter to optimize it.
+// these elements will appear repeatedly, you can set the FixedTop parameter to optimize it.
 //
 // Only support png and jpeg format yet, webP is not supported because no suitable processing
 // library was found in golang.
@@ -517,34 +517,20 @@ func (p *Page) ScrollScreenshot(opt *ScrollScreenshotOptions) ([]byte, error) {
 	var images []utils.ImgWithBox
 
 	for {
-		var clip *proto.PageViewport
+		clip := &proto.PageViewport{
+			X:     0,
+			Y:     scrollTop,
+			Width: metrics.CSSVisualViewport.ClientWidth,
+			Scale: 1,
+		}
 
 		scrollY := viewpointHeight - (opt.FixedTop + opt.FixedBottom)
 		if scrollTop+viewpointHeight > contentHeight {
-			clip = &proto.PageViewport{
-				X:      0,
-				Y:      scrollTop,
-				Width:  metrics.CSSVisualViewport.ClientWidth,
-				Height: contentHeight - scrollTop,
-				Scale:  1,
-			}
+			clip.Height = contentHeight - scrollTop
 		} else {
-			if scrollTop == 0 {
-				clip = &proto.PageViewport{
-					X:      0,
-					Y:      scrollTop,
-					Width:  metrics.CSSVisualViewport.ClientWidth,
-					Height: scrollY,
-					Scale:  1,
-				}
-			} else {
-				clip = &proto.PageViewport{
-					X:      0,
-					Y:      scrollTop + opt.FixedTop,
-					Width:  metrics.CSSVisualViewport.ClientWidth,
-					Height: scrollY,
-					Scale:  1,
-				}
+			clip.Height = scrollY
+			if scrollTop != 0 {
+				clip.Y += opt.FixedTop
 			}
 		}
 
@@ -567,6 +553,7 @@ func (p *Page) ScrollScreenshot(opt *ScrollScreenshotOptions) ([]byte, error) {
 		if scrollTop >= contentHeight {
 			break
 		}
+
 		err = p.Mouse.Scroll(0, scrollY, 1)
 		if err != nil {
 			return nil, fmt.Errorf("scroll error: %w", err)

page_test.go

@@ -777,12 +777,12 @@ func TestScreenshotFullPage(t *testing.T) {
 	})
 }
 
-func TestScrollScreenshotPage(t *testing.T) {
+func TestScrollScreenshot(t *testing.T) {
 	g := setup(t)
 
 	p := g.page.MustNavigate(g.srcFile("fixtures/scroll-y.html"))
 	p.MustElement("button")
-	data := p.MustScrollScreenshotPage()
+	data := p.MustScrollScreenshot()
 	img, err := png.Decode(bytes.NewBuffer(data))
 	g.E(err)
 	res := p.MustEval(`() => ({w: document.documentElement.scrollWidth, h: document.documentElement.scrollHeight})`)
@@ -797,53 +797,58 @@ func TestScrollScreenshotPage(t *testing.T) {
 	g.Eq(1280, res.Get("w").Int())
 	g.Eq(800, res.Get("h").Int())
 
-	p.MustScrollScreenshotPage()
+	p.MustScrollScreenshot()
 
 	noEmulation := g.newPage(g.blank())
 	g.E(noEmulation.SetViewport(nil))
-	noEmulation.MustScrollScreenshotPage()
+	noEmulation.MustScrollScreenshot()
+}
+
+func TestScrollScreenshotErrors(t *testing.T) {
+	g := setup(t)
+	g.cancelTimeout()
+
+	p := g.page.MustNavigate(g.srcFile("fixtures/scroll-y.html"))
 
 	g.Panic(func() {
 		// mock error for get CSSContentSize
 		g.mc.stubErr(1, proto.PageGetLayoutMetrics{})
-		p.MustScrollScreenshotPage()
+		p.MustScrollScreenshot()
 	})
 	g.Panic(func() {
 		g.mc.stub(1, proto.PageGetLayoutMetrics{}, func(_ StubSend) (gson.JSON, error) {
 			return gson.New(proto.PageGetLayoutMetricsResult{
 				CSSVisualViewport: &proto.PageVisualViewport{},
 			}), nil
 		})
-		p.MustScrollScreenshotPage()
+		p.MustScrollScreenshot()
 	})
 	g.Panic(func() {
 		g.mc.stub(1, proto.PageGetLayoutMetrics{}, func(_ StubSend) (gson.JSON, error) {
 			return gson.New(proto.PageGetLayoutMetricsResult{
 				CSSContentSize: &proto.DOMRect{},
 			}), nil
 		})
-		p.MustScrollScreenshotPage()
+		p.MustScrollScreenshot()
 	})
 	g.Panic(func() {
 		// mock error for scroll
 		g.mc.stubErr(1, proto.InputDispatchMouseEvent{})
-		p.MustScrollScreenshotPage()
+		p.MustScrollScreenshot()
 	})
-
 	g.Panic(func() {
 		// mock error for Screenshot
 		g.mc.stubErr(1, proto.PageCaptureScreenshot{})
-		p.MustScrollScreenshotPage()
+		p.MustScrollScreenshot()
 	})
-
 	g.Panic(func() {
 		// mock error for WaitStable
 		g.mc.stubErr(1, proto.DOMSnapshotCaptureSnapshot{})
-		p.MustScrollScreenshotPage()
+		p.MustScrollScreenshot()
 	})
 
 	// test unsupported format
-	_, err = p.ScrollScreenshot(&rod.ScrollScreenshotOptions{
+	_, err := p.ScrollScreenshot(&rod.ScrollScreenshotOptions{
 		/* cspell: disable-next-line */
 		Format:  proto.PageCaptureScreenshotFormatWebp,
 		Quality: gson.Int(10),