Add GetComputedRole to ChromeDriver

* Add `GetComputedRole` to Element in ChromeDriver

Bug: chromedriver:3507
Change-Id: Id3e3dc2fa99ca05286d17323c9c03cbf4f36ece7
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2416381
Reviewed-by: Sigurd Schneider <sigurds@chromium.org>
Reviewed-by: Shengfa Lin <shengfa@google.com>
Reviewed-by: John Chen <johnchen@chromium.org>
Reviewed-by: Mathias Bynens <mathias@chromium.org>
Commit-Queue: Maksim Sadym <sadym@chromium.org>
Cr-Commit-Position: refs/heads/master@{#809890}

chrome/test/chromedriver/client/command_executor.py

@@ -81,6 +81,8 @@ class Command(object):
       _Method.GET, '/session/:sessionId/element/:id/property/:name')
   GET_ELEMENT_COMPUTED_LABEL = (
       _Method.GET, '/session/:sessionId/element/:id/computedlabel')
+  GET_ELEMENT_COMPUTED_ROLE = (
+      _Method.GET, '/session/:sessionId/element/:id/computedrole')
   ELEMENT_EQUALS = (
       _Method.GET, '/session/:sessionId/element/:id/equals/:other')
   GET_COOKIES = (_Method.GET, '/session/:sessionId/cookie')

chrome/test/chromedriver/client/webelement.py

@@ -37,6 +37,9 @@ class WebElement(object):
   def GetComputedLabel(self):
     return self._Execute(Command.GET_ELEMENT_COMPUTED_LABEL)
 
+  def GetComputedRole(self):
+    return self._Execute(Command.GET_ELEMENT_COMPUTED_ROLE)
+
   def Click(self):
     self._Execute(Command.CLICK_ELEMENT)
 

chrome/test/chromedriver/element_commands.cc

@@ -744,47 +744,20 @@ Status ExecuteGetComputedLabel(Session* session,
                                const std::string& element_id,
                                const base::DictionaryValue& params,
                                std::unique_ptr<base::Value>* value) {
-  Status status = CheckElement(element_id);
+  std::unique_ptr<base::Value> axNode;
+  Status status = GetAXNodeByElementId(session, web_view, element_id, &axNode);
   if (status.IsError())
     return status;
 
-  int node_id;
-  std::unique_ptr<base::DictionaryValue> element(CreateElement(element_id));
-  status = web_view->GetNodeIdByElement(session->GetCurrentFrameId(), *element,
-                                        &node_id);
-
-  if (status.IsError())
-    return status;
-
-  base::DictionaryValue body;
-  body.SetInteger("nodeId", node_id);
-  body.SetBoolean("fetchRelatives", false);
-
-  std::unique_ptr<base::Value> result;
-
-  status = web_view->SendCommandAndGetResult("Accessibility.getPartialAXTree",
-                                             body, &result);
-  if (status.IsError())
-    return status;
-
-  base::Optional<base::Value> nodes = result->ExtractKey("nodes");
-  if (!nodes)
-    return Status(kUnknownError, "No `nodes` found in CDP response");
-
-  base::Value::ListView nodesList = nodes->GetList();
-  if (nodesList.size() != 1)
-    return Status(kUnknownError, "`nodes` in CDP response is not a list");
-
-  base::Value* node = &nodesList[0];
   // Computed label stores as `name` in the AXTree.
-  base::Optional<base::Value> name = node->ExtractKey("name");
-  if (!name) {
+  base::Optional<base::Value> nameNode = axNode->ExtractKey("name");
+  if (!nameNode) {
     // No computed label found. Return empty string.
     *value = std::make_unique<base::Value>("");
     return Status(kOk);
   }
 
-  base::Optional<base::Value> nameVal = name->ExtractKey("value");
+  base::Optional<base::Value> nameVal = nameNode->ExtractKey("value");
   if (!nameVal)
     return Status(kUnknownError,
                   "No name value found in the node in CDP response");
@@ -794,6 +767,33 @@ Status ExecuteGetComputedLabel(Session* session,
   return Status(kOk);
 }
 
+Status ExecuteGetComputedRole(Session* session,
+                              WebView* web_view,
+                              const std::string& element_id,
+                              const base::DictionaryValue& params,
+                              std::unique_ptr<base::Value>* value) {
+  std::unique_ptr<base::Value> axNode;
+  Status status = GetAXNodeByElementId(session, web_view, element_id, &axNode);
+  if (status.IsError())
+    return status;
+
+  base::Optional<base::Value> roleNode = axNode->ExtractKey("role");
+  if (!roleNode) {
+    // No computed role found. Return empty string.
+    *value = std::make_unique<base::Value>("");
+    return Status(kOk);
+  }
+
+  base::Optional<base::Value> roleVal = roleNode->ExtractKey("value");
+  if (!roleVal)
+    return Status(kUnknownError,
+                  "No role value found in the node in CDP response");
+
+  *value = std::make_unique<base::Value>(std::move(*roleVal));
+
+  return Status(kOk);
+}
+
 Status ExecuteIsElementDisplayed(Session* session,
                                  WebView* web_view,
                                  const std::string& element_id,

chrome/test/chromedriver/element_commands.h

@@ -154,6 +154,12 @@ Status ExecuteGetComputedLabel(Session* session,
                                const base::DictionaryValue& params,
                                std::unique_ptr<base::Value>* value);
 
+Status ExecuteGetComputedRole(Session* session,
+                              WebView* web_view,
+                              const std::string& element_id,
+                              const base::DictionaryValue& params,
+                              std::unique_ptr<base::Value>* value);
+
 Status ExecuteIsElementDisplayed(Session* session,
                                  WebView* web_view,
                                  const std::string& element_id,

chrome/test/chromedriver/element_util.cc

@@ -906,3 +906,45 @@ Status GetElementLocationInViewCenter(Session* session,
   *location = center_location;
   return Status(kOk);
 }
+
+Status GetAXNodeByElementId(Session* session,
+                            WebView* web_view,
+                            const std::string& element_id,
+                            std::unique_ptr<base::Value>* axNode) {
+  Status status = CheckElement(element_id);
+  if (status.IsError())
+    return status;
+
+  int node_id;
+  std::unique_ptr<base::DictionaryValue> element(CreateElement(element_id));
+  status = web_view->GetNodeIdByElement(session->GetCurrentFrameId(), *element,
+                                        &node_id);
+
+  if (status.IsError())
+    return status;
+
+  base::DictionaryValue body;
+  body.SetInteger("nodeId", node_id);
+  body.SetBoolean("fetchRelatives", false);
+
+  std::unique_ptr<base::Value> result;
+
+  status = web_view->SendCommandAndGetResult("Accessibility.getPartialAXTree",
+                                             body, &result);
+  if (status.IsError())
+    return status;
+
+  base::Optional<base::Value> nodes = result->ExtractKey("nodes");
+  if (!nodes)
+    return Status(kUnknownError, "No `nodes` found in CDP response");
+
+  base::Value::ListView nodesList = nodes->GetList();
+  if (nodesList.size() < 1)
+    return Status(kUnknownError, "Empty nodes list in CDP response");
+
+  if (nodesList.size() > 1)
+    return Status(kUnknownError, "Non-unique node in CDP response");
+
+  *axNode = std::make_unique<base::Value>(std::move(nodesList[0]));
+  return Status(kOk);
+}

chrome/test/chromedriver/element_util.h

@@ -164,4 +164,9 @@ Status GetElementLocationInViewCenter(Session* session,
                                       const std::string& element_id,
                                       WebPoint* location);
 
+Status GetAXNodeByElementId(Session* session,
+                            WebView* web_view,
+                            const std::string& element_id,
+                            std::unique_ptr<base::Value>* axNode);
+
 #endif  // CHROME_TEST_CHROMEDRIVER_ELEMENT_UTIL_H_

chrome/test/chromedriver/server/http_handler.cc

@@ -304,6 +304,9 @@ HttpHandler::HttpHandler(
       CommandMapping(kGet, "session/:sessionId/element/:id/computedlabel",
                      WrapToCommand("GetComputedLabel",
                                    base::Bind(&ExecuteGetComputedLabel))),
+      CommandMapping(kGet, "session/:sessionId/element/:id/computedrole",
+                     WrapToCommand("GetComputedRole",
+                                   base::Bind(&ExecuteGetComputedRole))),
       CommandMapping(kPost, "session/:sessionId/element/:id/click",
                      WrapToCommand("ClickElement",
                                    base::BindRepeating(&ExecuteClickElement))),

chrome/test/chromedriver/test/run_py_tests.py

@@ -538,13 +538,37 @@ class ChromeDriverTest(ChromeDriverBaseTestWithWebServer):
   def testStartStop(self):
     pass
 
-  def testGetComputedLabel(self):
-    self._driver.Load(self.GetHttpUrlForFile(
-        '/chromedriver/accessibility.html'))
-    element = self._driver.FindElement('css selector', '#first-header')
-    # print >> sys.stdout, "element.GetText: ", element.GetText()
-    computedLabel = element.GetComputedLabel()
-    self.assertEquals(computedLabel, 'header content')
+  def testGetComputedAttributes(self):
+    self._driver.Load(
+      self.GetHttpUrlForFile('/chromedriver/accessibility.html'))
+
+    firstHeaderElement = self._driver.FindElement(
+      'css selector', '#first-header')
+
+    self.assertEquals(firstHeaderElement.GetComputedLabel(), 'header content')
+    self.assertEquals(firstHeaderElement.GetComputedRole(), 'heading')
+
+  def testGetComputedAttributesForIgnoredNode(self):
+    self._driver.Load(
+      self.GetHttpUrlForFile('/chromedriver/accessibility.html'))
+
+    ignoredHeaderElement = self._driver.FindElement(
+      'css selector', '#ignored-header')
+
+    # GetComputedLabel for ignored node should return empty string.
+    self.assertEquals(ignoredHeaderElement.GetComputedLabel(), '')
+    self.assertEquals(ignoredHeaderElement.GetComputedRole(), 'Ignored')
+
+  def testGetComputedAttributesForUnrenderedNode(self):
+    self._driver.Load(
+      self.GetHttpUrlForFile('/chromedriver/accessibility.html'))
+
+    unrenderedHeaderElement = self._driver.FindElement(
+      'css selector', '#unrendered-header')
+
+    # GetComputedLabel for unrendered node should return empty string.
+    self.assertEquals(unrenderedHeaderElement.GetComputedLabel(), '')
+    self.assertEquals(unrenderedHeaderElement.GetComputedRole(), 'Ignored')
 
   def testLoadUrl(self):
     self._driver.Load(self.GetHttpUrlForFile('/chromedriver/empty.html'))

chrome/test/data/chromedriver/accessibility.html

@@ -1,3 +1,5 @@
 <!DOCTYPE html>
-    <title>Test</title>
-    <h1 id="first-header">header content</h1>
+<title>Test</title>
+<h1 id="first-header">header content</h1>
+<h1 id="ignored-header" role=presentation>ignored header content</h1>
+<h1 id="unrendered-header" hidden>unrendered header content</h1>

docs/chromedriver_status.md

@@ -41,6 +41,7 @@ Below is a list of all WebDriver commands and their current support in ChromeDri
 | GET    | /session/{session id}/element/{element id}/rect                | Get Element Rect           | Complete           |
 | GET    | /session/{session id}/element/{element id}/enabled             | Is Element Enabled         | Complete           |
 | GET    | /session/{session id}/element/{element id}/computedlabel       | Get Computed Label         | Complete           |
+| GET    | /session/{session id}/element/{element id}/computedrole        | Get Computed Role          | Complete           |
 | POST   | /session/{session id}/element/{element id}/click               | Element Click              | Partially Complete | [1996](https://bugs.chromium.org/p/chromedriver/issues/detail?id=1996)
 | POST   | /session/{session id}/element/{element id}/clear               | Element Clear              | Complete           |
 | POST   | /session/{session id}/element/{element id}/value               | Element Send Keys          | Partially Complete | [1999](https://bugs.chromium.org/p/chromedriver/issues/detail?id=1999)