Auto merge of #8564 - jgraham:webdriver_attr, r=Ms2ger

Implement Get Element Attribute WebDriver command

This intentionally doesn't implement the special handling for boolean
attributes yet, since that requires some kind of exhaustive list of all
such attributes

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2 files changed, 17 insertions, 0 deletions

diff --git a/components/script/script_task.rs b/components/script/script_task.rs
index 5a12d9e004f..5f881601bd7 100644
--- a/components/script/script_task.rs
+++ b/components/script/script_task.rs
@@ -1092,6 +1092,8 @@ impl ScriptTask {
                 webdriver_handlers::handle_get_active_element(&page, pipeline_id, reply),
             WebDriverScriptCommand::GetElementTagName(node_id, reply) =>
                 webdriver_handlers::handle_get_name(&page, pipeline_id, node_id, reply),
+            WebDriverScriptCommand::GetElementAttribute(node_id, name, reply) =>
+                webdriver_handlers::handle_get_attribute(&page, pipeline_id, node_id, name, reply),
             WebDriverScriptCommand::GetElementText(node_id, reply) =>
                 webdriver_handlers::handle_get_text(&page, pipeline_id, node_id, reply),
             WebDriverScriptCommand::GetFrameId(frame_id, reply) =>
diff --git a/components/script/webdriver_handlers.rs b/components/script/webdriver_handlers.rs
index cd49c8126f7..0bf2ede1aeb 100644
--- a/components/script/webdriver_handlers.rs
+++ b/components/script/webdriver_handlers.rs
@@ -203,6 +203,21 @@ pub fn handle_get_name(page: &Rc<Page>,
     }).unwrap();
 }
 
+pub fn handle_get_attribute(page: &Rc<Page>,
+                            pipeline: PipelineId,
+                            node_id: String,
+                            name: String,
+                            reply: IpcSender<Result<Option<String>, ()>>) {
+    reply.send(match find_node_by_unique_id(&*page, pipeline, node_id) {
+        Some(node) => {
+            Ok(node.downcast::<Element>().unwrap().GetAttribute(DOMString::from(name))
+               .map(String::from))
+        },
+        None => Err(())
+    }).unwrap();
+}
+
+
 pub fn handle_get_url(page: &Rc<Page>,
                       _pipeline: PipelineId,
                       reply: IpcSender<Url>) {