Refactor VR e2e tests

chrome/android/javatests/src/org/chromium/chrome/browser/vr_shell/VrTestBase.java

Index: chrome/android/javatests/src/org/chromium/chrome/browser/vr_shell/VrTestBase.java
diff --git a/chrome/android/javatests/src/org/chromium/chrome/browser/vr_shell/VrTestBase.java b/chrome/android/javatests/src/org/chromium/chrome/browser/vr_shell/VrTestBase.java
new file mode 100644
index 0000000000000000000000000000000000000000..d0bc08084143402e9b66f1f3ff95a3d957fc5ca4
--- /dev/null
+++ b/chrome/android/javatests/src/org/chromium/chrome/browser/vr_shell/VrTestBase.java
@@ -0,0 +1,212 @@
+// Copyright 2017 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.
+
+package org.chromium.chrome.browser.vr_shell;
+
+import static org.chromium.chrome.browser.vr_shell.VrUtils.POLL_CHECK_INTERVAL_LONG_MS;
+import static org.chromium.chrome.browser.vr_shell.VrUtils.POLL_CHECK_INTERVAL_SHORT_MS;
+import static org.chromium.chrome.browser.vr_shell.VrUtils.POLL_TIMEOUT_LONG_MS;
+import static org.chromium.chrome.browser.vr_shell.VrUtils.POLL_TIMEOUT_SHORT_MS;
+
+import org.chromium.base.Log;
+import org.chromium.base.test.util.UrlUtils;
+import org.chromium.chrome.test.ChromeTabbedActivityTestBase;
+import org.chromium.content.browser.test.util.ClickUtils;
+import org.chromium.content.browser.test.util.Criteria;
+import org.chromium.content.browser.test.util.CriteriaHelper;
+import org.chromium.content.browser.test.util.JavaScriptUtils;
+import org.chromium.content_public.browser.WebContents;
+
+import java.util.concurrent.Callable;
+import java.util.concurrent.TimeUnit;
+import java.util.concurrent.TimeoutException;
+
+/**
+ * This is a workaround for testing aspects of WebVR that aren't testable with
+ * WebVR's mocked layout tests, such as E2E tests.
+ *
+ * The general test flow is:
+ * - Load the HTML file containing the test, which:
+ *   - Loads the WebVR boilerplate code and some test functions
+ *   - Sets up common elements like the canvas and synchronization variable
+ *   - Sets up any steps that need to be triggered by the Java code
+ * - Check if any VRDisplay objects were found and fail the test if it doesn't
+ *       match what we expect for that test
+ * - Repeat:
+ *   - Run any necessary Java-side code, e.g. trigger a user action
+ *   - Trigger the next JavaScript test step and wait for it to finish
+ *
+ * The JavaScript code will automatically process test results once all
+ * testharness.js tests are done, just like in layout tests. Once the results
+ * are processed, the JavaScript code will automatically signal the Java code,
+ * which can then grab the results and pass/fail the instrumentation test.
+ */
+public class VrTestBase extends ChromeTabbedActivityTestBase {
+    private static final String TAG = "VrTestBase";
+    protected static final String TEST_DIR = "chrome/test/data/android/webvr_instrumentation";
+    protected static final int PAGE_LOAD_TIMEOUT_S = 10;
+
+    protected WebContents mWebContents;
+
+    @Override
+    protected void setUp() throws Exception {
+        super.setUp();
+        mWebContents = getActivity().getActivityTab().getWebContents();
+    }
+
+    @Override
+    public void startMainActivity() throws InterruptedException {
+        startMainActivityOnBlankPage();
+    }
+
+    /**
+     * Gets the file:// URL to the test file
+     * @param testName The name of the test whose file will be retrieved
+     * @return The file:// URL to the specified test file
+     */
+    protected String getHtmlTestFile(String testName) {
+        return "file://" + UrlUtils.getIsolatedTestFilePath(TEST_DIR) + "/html/" + testName
+                + ".html";
+    }
+
+    /**
+     * Blocks until the promise returned by nagivator.getVRDisplays() resolves,
+     * then checks whether a VRDisplay was actually found.
+     * @param webContents The WebContents to run the JavaScript through
+     * @return Whether a VRDisplay was found
+     */
+    protected boolean vrDisplayFound(WebContents webContents) {
+        pollJavaScriptBoolean("vrDisplayPromiseDone", POLL_TIMEOUT_SHORT_MS, webContents);
+        return !runJavaScriptOrFail("vrDisplay", POLL_TIMEOUT_SHORT_MS, webContents).equals("null");
+    }
+
+    /**
+     * Use to tap in the middle of the screen, triggering the canvas' onclick
+     * to fulfil WebVR's gesture requirement for presenting.
+     */
+    protected void enterVrTap() {
+        ClickUtils.mouseSingleClickView(
+                getInstrumentation(), getActivity().getWindow().getDecorView().getRootView());
+    }
+
+    /**
+     * Taps in the middle of the screen then waits for the JavaScript step to finish.
+     * @param webContents The WebContents for the tab the JavaScript step is in
+     */
+    protected void enterVrTapAndWait(WebContents webContents) {
+        enterVrTap();
+        waitOnJavaScriptStep(webContents);
+    }
+
+    /**
+     * Use to simulate a Daydream View NFC scan without blocking afterwards
+     */
+    protected void simNfcScan() {
+        VrUtils.simNfc(getActivity());
+    }
+
+    /**
+     * Simulate an NFC scan and wait for the JavaScript code in the given
+     * WebContents to signal that it is done with the step.
+     * @param webContents The WebContents for the JavaScript that will be polled
+     */
+    protected void simNfcScanAndWait(WebContents webContents) {
+        simNfcScan();
+        waitOnJavaScriptStep(webContents);
+    }
+
+    /**
+     * Helper function to run the given JavaScript, return the return value,
+     * and fail if a timeout/interrupt occurs so we don't have to catch or
+     * declare exceptions all the time.
+     * @param js The JavaScript to run
+     * @param timeout The timeout in milliseconds before a failure
+     * @param webContents The WebContents object to run the JavaScript in
+     * @return The return value of the JavaScript
+     */
+    protected String runJavaScriptOrFail(String js, int timeout, WebContents webContents) {
+        try {
+            return JavaScriptUtils.executeJavaScriptAndWaitForResult(
+                    webContents, js, timeout, TimeUnit.MILLISECONDS);
+        } catch (InterruptedException | TimeoutException e) {
+            fail("Fatal interruption or timeout running JavaScript: " + js);
+        }
+        return "Not reached";
+    }
+
+    /**
+     * Ends the test harness test and checks whether there it passed
+     * @param webContents The WebContents for the tab to check results in
+     * @return "Passed" if test passed, String with failure reason otherwise
+     */
+    protected String checkResults(WebContents webContents) {
+        if (runJavaScriptOrFail("testPassed", POLL_TIMEOUT_SHORT_MS, webContents).equals("true")) {
+            return "Passed";
+        }
+        return runJavaScriptOrFail("resultString", POLL_TIMEOUT_SHORT_MS, webContents);
+    }
+
+    /**
+     * Helper function to end the test harness test and assert that it passed,
+     * setting the failure reason as the description if it didn't.
+     * @param webContents The WebContents for the tab to check test results in
+     */
+    protected void endTest(WebContents webContents) {
+        assertEquals("Passed", checkResults(webContents));
+    }
+
+    /**
+     * Polls the provided JavaScript boolean until the timeout is reached or
+     * the boolean is true.
+     * @param boolName The name of the JavaScript boolean or expression to poll
+     * @param timeoutMs The polling timeout in milliseconds
+     * @param webContents The WebContents to run the JavaScript through
+     * @return True if the boolean evaluated to true, false if timed out
+     */
+    protected boolean pollJavaScriptBoolean(
+            final String boolName, int timeoutMs, final WebContents webContents) {
+        try {
+            CriteriaHelper.pollInstrumentationThread(Criteria.equals(true, new Callable<Boolean>() {
+                @Override
+                public Boolean call() {
+                    String result = "false";
+                    try {
+                        result = JavaScriptUtils.executeJavaScriptAndWaitForResult(webContents,
+                                boolName, POLL_CHECK_INTERVAL_SHORT_MS, TimeUnit.MILLISECONDS);
+                    } catch (InterruptedException | TimeoutException e) {
+                        // Expected to happen regularly, do nothing
+                    }
+                    return Boolean.parseBoolean(result);
+                }
+            }), timeoutMs, POLL_CHECK_INTERVAL_LONG_MS);
+        } catch (AssertionError e) {
+            Log.d(TAG, "pollJavaScriptBoolean() timed out");
+            return false;
+        }
+        return true;
+    }
+
+    /**
+     * Waits for a JavaScript step to finish, asserting that the step finished
+     * instead of timing out.
+     * @param webContents The WebContents for the tab the JavaScript step is in
+     */
+    protected void waitOnJavaScriptStep(WebContents webContents) {
+        assertTrue("Polling JavaScript boolean javascriptDone succeeded",
+                pollJavaScriptBoolean("javascriptDone", POLL_TIMEOUT_LONG_MS, webContents));
+        // Reset the synchronization boolean
+        runJavaScriptOrFail("javascriptDone = false", POLL_TIMEOUT_SHORT_MS, webContents);
+    }
+
+    /**
+     * Executes a JavaScript step function using the given WebContents.
+     * @param stepFunction The JavaScript step function to call
+     * @param webContents The WebContents for the tab the JavaScript is in
+     */
+    protected void executeStepAndWait(String stepFunction, WebContents webContents) {
+        // Run the step and block
+        JavaScriptUtils.executeJavaScript(webContents, stepFunction);
+        waitOnJavaScriptStep(webContents);
+    }
+}