Move web_js_test.h upstream

ios/web/public/test/web_js_test.h

Index: ios/web/public/test/web_js_test.h
diff --git a/ios/web/public/test/web_js_test.h b/ios/web/public/test/web_js_test.h
new file mode 100644
index 0000000000000000000000000000000000000000..74550e4de0784e1929b62adaee6b0345717b43c1
--- /dev/null
+++ b/ios/web/public/test/web_js_test.h
@@ -0,0 +1,123 @@
+// Copyright 2013 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.
+
+#ifndef IOS_INTERNAL_CHROME_BROWSER_WEB_WEB_JS_TEST_H_
+#define IOS_INTERNAL_CHROME_BROWSER_WEB_WEB_JS_TEST_H_
+
+#import <Foundation/Foundation.h>
+
+#import "base/mac/bundle_locations.h"
+#import "base/mac/scoped_nsobject.h"
+#include "testing/gtest_mac.h"
+
+class GURL;
+
+namespace web {
+
+// Base fixture mixin for testing JavaScripts.
+template <class WebTestT>
+class WebJsTest : public WebTestT {
+ public:
+  WebJsTest(NSArray* java_script_paths)
+      : java_script_paths_([java_script_paths retain]) {}

[Eugene But (OOO till 7-30), 2016/07/13 15:22:27]

NIT: Consider copying array since the input can be mutable.

+
+ protected:
+  // Loads |html| and inject JavaScripts at |javaScriptPaths_|.
+  void LoadHtmlAndInject(NSString* html) {
+    WebTestT::LoadHtml(html);
+    Inject();
+  }
+
+  // Returns a NSString representation of the JavaScript's evaluation results;
+  // the JavaScript is passed in as a |format| and its arguments.
+  NSString* EvaluateJavaScriptWithFormat(NSString* format, ...)
+      __attribute__((format(__NSString__, 2, 3)));
+
+  // Helper method that EXPECTs the |java_script| evaluation results on each
+  // element obtained by scripts in |get_element_javas_cripts|; the expected
+  // result is the corresponding entry in |expected_results|.
+  void EvaluateJavaScriptOnElementsAndCheck(NSString* java_script,
+                                            NSArray* get_element_java_scripts,
+                                            NSArray* expected_results);
+
+  // Helper method that EXPECTs the |java_script| evaluation results on each
+  // element obtained by JavaScripts in |get_element_java_scripts|. The
+  // expected results are boolean and are true only for elements in
+  // |get_element_java_scripts_expecting_true| which is subset of
+  // |get_element_java_scripts|.
+  void EvaluateBooleanJavaScriptOnElementsAndCheck(
+      NSString* java_script,
+      NSArray* get_element_java_scripts,
+      NSArray* get_element_java_scripts_expecting_true);
+
+ private:
+  // Injects JavaScript at |java_script_paths_|.
+  void Inject();
+
+  base::scoped_nsobject<NSArray> java_script_paths_;
+};
+
+template <class WebTestT>
+void WebJsTest<WebTestT>::Inject() {
+  // Wait until main web injection has occured.

[Eugene But (OOO till 7-30), 2016/07/13 15:22:27]

Do we still need this "wait"? I would assume that web JS is injected immediately
into WKWebView.

+  NSString* beacon = nil;
+  do {
+    beacon = WebTestT::EvaluateJavaScriptAsString(@"typeof __gCrWeb");
+  } while (![beacon isEqualToString:@"object"]);
+  for (NSString* java_script_path in java_script_paths_.get()) {
+    NSString* path =
+        [base::mac::FrameworkBundle() pathForResource:java_script_path
+                                               ofType:@"js"];
+    WebTestT::EvaluateJavaScriptAsString([NSString

[Eugene But (OOO till 7-30), 2016/07/13 15:22:27]

NIT: EvaluateJavaScriptAsString is marked as deprecated. Can you replace this
with |ExecuteJavaScript|?

We plan to clean this up later, so if you prefer to leave the code as it is it's
fine.

+        stringWithContentsOfFile:path
+                        encoding:NSUTF8StringEncoding
+                           error:nil]);
+  }
+}
+
+template <class WebTestT>
+NSString* WebJsTest<WebTestT>::EvaluateJavaScriptWithFormat(NSString* format,
+                                                            ...) {
+  va_list args;
+  va_start(args, format);
+  base::scoped_nsobject<NSString> java_script(
+      [[NSString alloc] initWithFormat:format arguments:args]);
+  va_end(args);
+
+  return WebTestT::EvaluateJavaScriptAsString(java_script);
+}
+
+template <class WebTestT>
+void WebJsTest<WebTestT>::EvaluateJavaScriptOnElementsAndCheck(
+    NSString* java_script,
+    NSArray* get_element_java_scripts,
+    NSArray* expected_results) {
+  for (NSUInteger i = 0; i < get_element_java_scripts.count; ++i) {
+    EXPECT_NSEQ(
+        expected_results[i],
+        EvaluateJavaScriptWithFormat(java_script, get_element_java_scripts[i]));
+  }
+}
+
+template <class WebTestT>
+void WebJsTest<WebTestT>::EvaluateBooleanJavaScriptOnElementsAndCheck(
+    NSString* java_script,
+    NSArray* get_element_java_scripts,
+    NSArray* get_element_java_scripts_expecting_true) {
+  for (NSUInteger index = 0; index < get_element_java_scripts.count; ++index) {
+    NSString* get_element_java_script = get_element_java_scripts[index];
+    NSString* expected = [get_element_java_scripts_expecting_true
+                             containsObject:get_element_java_script]
+                             ? @"true"
+                             : @"false";
+    EXPECT_NSEQ(expected, EvaluateJavaScriptWithFormat(java_script,
+                                                       get_element_java_script))
+        << [NSString stringWithFormat:@"%@ on %@ should return %@", java_script,
+                                      get_element_java_script, expected];
+  }
+}
+
+}  // namespace web
+
+#endif  // IOS_INTERNAL_CHROME_BROWSER_WEB_WEB_JS_TEST_H_