[debugger] Various break-related functionality in test wrapper

test/debugger/test-api.js

 // Copyright 2016 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // If true, prints all messages sent and received by inspector.
 const printProtocolMessages = false;
 
 // The active wrapper instance.
 let activeWrapper = undefined;
 
@@ skipping 15 matching lines @@
 class DebugWrapper {
   constructor() {
     // Message dictionary storing {id, message} pairs.
     this.receivedMessages = {};
 
     // Each message dispatched by the Debug wrapper is assigned a unique number
     // using nextMessageId.
     this.nextMessageId = 0;
 
     // The listener method called on certain events.
-    this.listener = () => undefined;
+    this.listener = undefined;
 
     // Register as the active wrapper.
     assertTrue(activeWrapper === undefined);
     activeWrapper = this;
   }
 
-  enable() {
-    const {msgid, msg} = this.createMessage("Debugger.enable");
+  enable() { this.sendMessageForMethodChecked("Debugger.enable"); }
+  disable() { this.sendMessageForMethodChecked("Debugger.disable"); }
+
+  setListener(listener) { this.listener = listener; }
+
+  stepOver() { this.sendMessageForMethodChecked("Debugger.stepOver"); }
+  stepInto() { this.sendMessageForMethodChecked("Debugger.stepInto"); }
+  stepOut() { this.sendMessageForMethodChecked("Debugger.stepOut"); }
+
+  // Returns the resulting breakpoint id.
+  setBreakPoint(func, opt_line, opt_column, opt_condition) {
+    assertTrue(%IsFunction(func));
+    assertFalse(%FunctionIsAPIFunction(func));
+
+    // TODO(jgruber): We handle only script breakpoints for now.
+    // TODO(jgruber): Handle conditions.
+
+    const script = %FunctionGetScript(func);
+    assertTrue(!!script.id);

[Yang, 2016/10/28 05:51:06]

This still relies on the script wrapper object, which we want to eventually
remove from messages.js

Could we have a %FunctionGetScriptId that returns the script id directly, and
mark %FunctionGetScript as to-be-removed with a TODO?

[jgruber, 2016/10/28 07:36:27]

Done.

+
+    const offset = %FunctionGetScriptSourcePosition(func);
+    const loc = %ScriptLocationFromLine(script, opt_line, opt_column, offset);
+
+    const {msgid, msg} = this.createMessage(
+        "Debugger.setBreakpoint",
+        { location : { scriptId : script.id.toString()
+                     , lineNumber : loc.line
+                     , columnNumber : loc.column
+                     }
+        });
+    this.sendMessage(msg);
+
+    const reply = this.receivedMessages[msgid];
+    const breakid = reply.result.breakpointId;
+    assertTrue(breakid !== undefined);
+
+    return breakid;
+  }
+
+  clearBreakPoint(breakid) {
+    const {msgid, msg} = this.createMessage(
+        "Debugger.removeBreakpoint", { breakpointId : breakid });
     this.sendMessage(msg);
     assertTrue(this.receivedMessages[msgid] !== undefined);
   }
 
-  disable() {
-    const {msgid, msg} = this.createMessage("Debugger.disable");
+  // Returns the serialized result of the given expression. For example:
+  // {"type":"number", "value":33, "description":"33"}.
+  evaluate(frameid, expression) {
+    const {msgid, msg} = this.createMessage(
+        "Debugger.evaluateOnCallFrame",
+        { callFrameId : frameid
+        , expression : expression
+        });
     this.sendMessage(msg);
-    assertTrue(this.receivedMessages[msgid] !== undefined);
-  }
 
-  setListener(listener) {
-    this.listener = listener;
+    const reply = this.receivedMessages[msgid];
+    return reply.result.result;
   }
 
   // --- Internal methods. -----------------------------------------------------
 
   getNextMessageId() {
     return this.nextMessageId++;
   }
 
   createMessage(method, params) {
     const id = this.getNextMessageId();
@@ skipping 14 matching lines @@
     }
 
     this.dispatchMessage(parsedMessage);
   }
 
   sendMessage(message) {
     if (printProtocolMessages) print(message);
     send(message);
   }
 
+  sendMessageForMethodChecked(method) {
+    const {msgid, msg} = this.createMessage(method);
+    this.sendMessage(msg);
+    assertTrue(this.receivedMessages[msgid] !== undefined);
+  }
+
   // --- Message handlers. -----------------------------------------------------
 
   dispatchMessage(message) {
     const method = message.method;
-    if (method == "Debugger.scriptParsed") {
+    if (method == "Debugger.paused") {
+      this.handleDebuggerPaused(message);
+    } else if (method == "Debugger.scriptParsed") {
       this.handleDebuggerScriptParsed(message);
     }
   }
 
+  handleDebuggerPaused(message) {
+    const params = message.params;
+
+    // TODO(jgruber): Arguments as needed.
+    let execState = { frames: params.callFrames };
+    this.invokeListener(DebugEvent.Break, execState);
+  }
+
   handleDebuggerScriptParsed(message) {
     const params = message.params;
     let eventData = { scriptId : params.scriptId
                     , eventType : DebugEvent.AfterCompile
                     }
 
     // TODO(jgruber): Arguments as needed. Still completely missing exec_state,
     // and eventData used to contain the script mirror instead of its id.
-    this.listener(DebugEvent.AfterCompile, undefined, eventData, undefined);
+    this.invokeListener(DebugEvent.AfterCompile, undefined, eventData,
+                        undefined);
+  }
+
+  invokeListener(event, exec_state, event_data, data) {
+    if (this.listener) {
+      this.listener(event, exec_state, event_data, data);
+    }
   }
 }