Add step over mode

browser/breakpoint.go

@@ -13,6 +13,7 @@ import (
 
 	"github.com/gorilla/websocket"
 
+	"github.com/grafana/sobek"
 	"github.com/grafana/xk6-browser/env"
 )
 
@@ -53,6 +54,12 @@ type breakpointRegistry struct {
 
 	muVariables sync.RWMutex
 	variables   []map[string]debugVarFunc
+
+	// stepOverMode is used to pause the script execution
+	// on each line whether the breakpoint is hit or not.
+	//
+	// resume(true) disables the stepOverMode.
+	stepOverMode bool
 }
 
 func newBreakpointRegistry() *breakpointRegistry {
@@ -67,7 +74,8 @@ func newBreakpointRegistry() *breakpointRegistry {
 		// 	Line: 32,
 		// },
 		// },
-		pauser: make(chan chan struct{}, 1),
+		pauser:       make(chan chan struct{}, 1),
+		stepOverMode: true,
 	}
 }
 
@@ -83,10 +91,23 @@ func (br *breakpointRegistry) update(breakpoints []breakpoint) {
 	br.breakpoints = breakpoints
 }
 
+func (br *breakpointRegistry) shouldResume() bool {
+	return br.stepOverMode
+}
+
 func (br *breakpointRegistry) matches(p position) (breakpoint, bool) {
 	br.muBreakpoints.RLock()
 	defer br.muBreakpoints.RUnlock()
 
+	// stepOverMode allows pausing the script execution
+	// on the remaining lines.
+	if br.stepOverMode {
+		return breakpoint{
+			File: p.Filename,
+			Line: p.Line,
+		}, true
+	}
+
 	// We need to compare between /path/to/test-script.js and file:///path/to/test-script.js
 	for _, b := range br.breakpoints {
 		if strings.Contains(p.Filename, b.File) && b.Line == p.Line {
@@ -111,9 +132,22 @@ func (br *breakpointRegistry) pause(b breakpoint, column int, funcName string) e
 }
 
 // resume resumes the script execution.
-func (br *breakpointRegistry) resume() {
-	c := <-br.pauser
-	close(c)
+func (br *breakpointRegistry) resume(stepOut bool) {
+	log.Printf("resuming: stepOut=%v", stepOut)
+	if stepOut {
+		br.setStepOverMode(false)
+	}
+	select {
+	case c := <-br.pauser:
+		close(c)
+	default:
+		log.Printf("resuming: nothing to resume")
+	}
+}
+
+func (br *breakpointRegistry) setStepOverMode(on bool) {
+	log.Printf("stepOverMode set to %v", on)
+	br.stepOverMode = on
 }
 
 // setVar adds a variable to the registry.
@@ -149,19 +183,21 @@ func (br *breakpointRegistry) vars() []map[string]debugVarFunc {
 
 // pauseOnBreakpoint is a helper that pauses the script execution
 // when a breakpoint is hit in the script.
-func pauseOnBreakpoint(vu moduleVU) {
-	bp := vu.breakpointRegistry
+func pauseOnBreakpoint(bp *breakpointRegistry, rt *sobek.Runtime) {
 	if !bp.isActive() {
 		return
 	}
 
-	pos := getCurrentLineNumber(vu)
+	pos := getCurrentLineNumber(rt)
 	log.Printf("current line: %v", pos)
 
 	b, ok := bp.matches(pos)
 	if !ok {
 		return
 	}
+	if bp.shouldResume() {
+		bp.resume(false)
+	}
 
 	log.Printf("pausing at %v:%v", pos.Filename, pos.Line)
 	if err := bp.pause(b, pos.Column, pos.FuncName); err != nil {
@@ -172,7 +208,7 @@ func pauseOnBreakpoint(vu moduleVU) {
 type breakpointUpdateResumer interface {
 	update(breakpoints []breakpoint)
 	vars() []map[string]debugVarFunc
-	resume()
+	resume(stepOut bool)
 }
 
 type breakpointClient struct {
@@ -251,10 +287,14 @@ func (bc *breakpointClient) updateBreakpoints(data []byte) {
 }
 
 func (bc *breakpointClient) handleResume() {
-	bc.registry.resume()
+	bc.registry.resume(true)
 }
 
 func (bc *breakpointClient) sendPause(b breakpoint, column int, funcName string) error {
+	if bc == nil {
+		return nil
+	}
+
 	type variable struct {
 		Name  string `json:"name"`
 		Value any    `json:"value"`

browser/breakpoint_test.go

@@ -26,10 +26,11 @@ func (bpt *breakpointTest) update(breakpoints []breakpoint) {
 	bpt.updated = breakpoints
 }
 
-func (bpt *breakpointTest) resume() {
+func (bpt *breakpointTest) resume(stepOut bool) {
 	bpt.mu.Lock()
 	defer bpt.mu.Unlock()
 	bpt.resumeCalled = true
+	_ = stepOut
 }
 
 func (bpt *breakpointTest) vars() []map[string]debugVarFunc {
@@ -143,3 +144,72 @@ func TestBreakpointClient_SendPause(t *testing.T) {
 		t.Fatalf("timeout waiting for server to handle the pause message")
 	}
 }
+
+func TestBreakpoint_Stepover(t *testing.T) {
+	t.Run("stepover", func(t *testing.T) {
+		reg := newBreakpointRegistry()
+		reg.setStepOverMode(true)
+		bp, ok := reg.matches(position{Filename: "foo.js", Line: 1})
+		assert.True(t, ok)
+		assert.Equal(t, breakpoint{File: "foo.js", Line: 1}, bp)
+	})
+
+	t.Run("stepover_off", func(t *testing.T) {
+		reg := newBreakpointRegistry()
+		reg.setStepOverMode(false)
+		_, ok := reg.matches(position{Filename: "foo.js", Line: 1})
+		assert.False(t, ok)
+	})
+
+	t.Run("stepover_off_with_breakpoint", func(t *testing.T) {
+		reg := newBreakpointRegistry()
+		reg.setStepOverMode(false)
+		reg.update([]breakpoint{{File: "foo.js", Line: 1}})
+		bp, ok := reg.matches(position{Filename: "foo.js", Line: 1})
+		assert.True(t, ok)
+		assert.Equal(t, breakpoint{File: "foo.js", Line: 1}, bp)
+	})
+
+	t.Run("pause_stepover_on", func(t *testing.T) {
+		reg := newBreakpointRegistry()
+		reg.setStepOverMode(true)
+
+		bp := breakpoint{File: "foo.js", Line: 1}
+
+		err := make(chan error)
+		go func() {
+			err <- reg.pause(bp, 0, "bar")
+		}()
+		go func() {
+			reg.resume(false)
+		}()
+		select {
+		case err := <-err:
+			require.NoError(t, err)
+		case <-time.After(5 * time.Second):
+			t.Fatalf("timeout waiting for pause to be called")
+		}
+		require.True(t, reg.stepOverMode)
+	})
+	t.Run("pause_stepover_off", func(t *testing.T) {
+		reg := newBreakpointRegistry()
+		reg.setStepOverMode(true)
+
+		bp := breakpoint{File: "foo.js", Line: 1}
+
+		err := make(chan error)
+		go func() {
+			err <- reg.pause(bp, 0, "bar")
+		}()
+		go func() {
+			reg.resume(true)
+		}()
+		select {
+		case err := <-err:
+			require.NoError(t, err)
+		case <-time.After(5 * time.Second):
+			t.Fatalf("timeout waiting for pause to be called")
+		}
+		require.False(t, reg.stepOverMode)
+	})
+}

browser/browser_context_mapping.go

@@ -71,7 +71,7 @@ func mapBrowserContext(vu moduleVU, bc *common.BrowserContext) mapping { //nolin
 			})
 		},
 		"cookies": func(urls ...string) *sobek.Promise {
-			pauseOnBreakpoint(vu)
+			pauseOnBreakpoint(vu.breakpointRegistry, vu.Runtime())
 
 			return k6ext.Promise(vu.Context(), func() (any, error) {
 				return bc.Cookies(urls...) //nolint:wrapcheck

browser/browser_mapping.go

@@ -36,7 +36,7 @@ func mapBrowser(vu moduleVU) mapping { //nolint:funlen,cyclop,gocognit
 			return b.IsConnected(), nil
 		},
 		"newContext": func(opts sobek.Value) (*sobek.Promise, error) {
-			pauseOnBreakpoint(vu)
+			pauseOnBreakpoint(vu.breakpointRegistry, vu.Runtime())
 
 			popts, err := parseBrowserContextOptions(vu.Runtime(), opts)
 			if err != nil {
@@ -73,7 +73,7 @@ func mapBrowser(vu moduleVU) mapping { //nolint:funlen,cyclop,gocognit
 			return b.Version(), nil
 		},
 		"newPage": func(opts sobek.Value) (*sobek.Promise, error) {
-			pauseOnBreakpoint(vu)
+			pauseOnBreakpoint(vu.breakpointRegistry, vu.Runtime())
 
 			popts, err := parseBrowserContextOptions(vu.Runtime(), opts)
 			if err != nil {

browser/helpers.go

@@ -69,8 +69,7 @@ func sobekEmptyString(v sobek.Value) bool {
 	return !sobekValueExists(v) || strings.TrimSpace(v.String()) == ""
 }
 
-func getCurrentLineNumber(vu moduleVU) position {
-	rt := vu.Runtime()
+func getCurrentLineNumber(rt *sobek.Runtime) position {
 	// var parent string
 	var buf [2]sobek.StackFrame
 	frames := rt.CaptureCallStack(2, buf[:0])