[DevTools] New harness for inspector-protocol layout tests

third_party/WebKit/LayoutTests/inspector-protocol/resources/tracing-test.js

+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+(function initialize_tracingHarness(testRunner, session) {
+
+  class TracingHelper {
+    startTracing(callback) {
+      this.startTracingWithArguments({ "categories": "-*,disabled-by-default-devtools.timeline,devtools.timeline", "type": "", "options": "" }, callback);
+    }
+
+    startTracingAndSaveAsStream(callback) {
+      var args = {
+        "categories": "-*,disabled-by-default-devtools.timeline,devtools.timeline",
+        "type": "",
+        "options": "",
+        "transferMode": "ReturnAsStream"
+      };
+      this.startTracingWithArguments(args, callback);
+    }
+
+    startTracingWithArguments(args, callback) {
+      session.protocol.Tracing.start(args).then(onStart);
+      function onStart(response) {
+        testRunner.log("Recording started");
+        callback();
+      }
+    }
+
+    stopTracing(callback) {
+      this.devtoolsEvents = [];
+      var dataCollected = reply => {
+        var allEvents = reply.params.value;
+        this.devtoolsEvents = this.devtoolsEvents.concat(allEvents.filter(function(e) {
+          return /devtools.timeline/.test(e.cat);
+        }));
+      };
+
+      var tracingComplete = event => {
+        testRunner.log("Tracing complete");
+        session.protocol.Tracing.offTracingComplete(tracingComplete);
+        session.protocol.Tracing.offDataCollected(dataCollected);
+        callback(this.devtoolsEvents);
+      };
+
+      session.protocol.Tracing.onTracingComplete(tracingComplete);
+      session.protocol.Tracing.onDataCollected(dataCollected);
+      session.protocol.Tracing.end();
+    }
+
+    stopTracingAndReturnStream(callback) {
+      session.protocol.Tracing.onTracingComplete(tracingComplete);
+      session.protocol.Tracing.onDataCollected(dataCollected);
+      session.protocol.Tracing.end();
+
+      function dataCollected(reply) {
+        testRunner.log("FAIL: dataCollected event should not be fired when returning trace as stream.");
+      }
+
+      function tracingComplete(event) {
+        testRunner.log("Tracing complete");
+        session.protocol.Tracing.offTracingComplete(tracingComplete);
+        session.protocol.Tracing.offDataCollected(dataCollected);
+        callback(event.params.stream);
+      }
+    }
+
+    retrieveStream(streamHandle, offset, chunkSize, callback) {
+      var result = "";
+      var had_eof = false;
+
+      var readArguments = { handle: streamHandle };
+      if (typeof chunkSize === "number")
+        readArguments.size = chunkSize;
+      var firstReadArguments = JSON.parse(JSON.stringify(readArguments));
+      if (typeof offset === "number")
+        firstReadArguments.offset = 0;
+      session.protocol.IO.read(firstReadArguments).then(message => onChunkRead(message.result));
+      // Assure multiple in-lfight reads are fine (also, save on latencies).
+      session.protocol.IO.read(readArguments).then(message => onChunkRead(message.result));
+
+      function onChunkRead(response) {
+        if (had_eof)
+          return;
+        result += response.data;
+        if (response.eof) {
+          // Ignore stray callbacks from proactive read requests.
+          had_eof = true;
+          callback(result);
+          return;
+        }
+        session.protocol.IO.read(readArguments).then(message => onChunkRead(message.result));
+      }
+    }
+
+    findEvents(name, ph, condition) {
+      return this.devtoolsEvents.filter(e => e.name === name && e.ph === ph && (!condition || condition(e)));
+    }
+
+    findEvent(name, ph, condition) {
+      var events = this.findEvents(name, ph, condition);
+      if (events.length)
+        return events[0];
+      throw new Error("Couldn't find event " + name + " / " + ph + "\n\n in " + JSON.stringify(this.devtoolsEvents, null, 2));
+    }
+
+    invokeAsyncWithTracing(functionName, callback) {
+      this.startTracing(async () => {
+        var data = await session.evaluateAsync(functionName + "()");
+        this.stopTracing(devtoolsEvents => callback(devtoolsEvents, data));
+      });
+    }
+  }
+
+  return new TracingHelper();
+})