Auto merge of #23581 - georgeroman:implement_get_page_source_wd_command, r=jdm

Implement GetPageSource WebDriver command

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- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors

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- [X] There are tests for these changes

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components/script/script_thread.rs

@@ -1902,6 +1902,9 @@ impl ScriptThread {
             WebDriverScriptCommand::GetActiveElement(reply) => {
                 webdriver_handlers::handle_get_active_element(&*documents, pipeline_id, reply)
             },
+            WebDriverScriptCommand::GetPageSource(reply) => {
+                webdriver_handlers::handle_get_page_source(&*documents, pipeline_id, reply)
+            },
             WebDriverScriptCommand::GetCookies(reply) => {
                 webdriver_handlers::handle_get_cookies(&*documents, pipeline_id, reply)
             },

components/script/webdriver_handlers.rs

@@ -10,6 +10,7 @@ use crate::dom::bindings::codegen::Bindings::HTMLInputElementBinding::HTMLInputE
 use crate::dom::bindings::codegen::Bindings::HTMLOptionElementBinding::HTMLOptionElementMethods;
 use crate::dom::bindings::codegen::Bindings::NodeBinding::NodeMethods;
 use crate::dom::bindings::codegen::Bindings::WindowBinding::WindowMethods;
+use crate::dom::bindings::codegen::Bindings::XMLSerializerBinding::XMLSerializerMethods;
 use crate::dom::bindings::conversions::{
     ConversionResult, FromJSValConvertible, StringificationBehavior,
 };
@@ -24,6 +25,7 @@ use crate::dom::htmlinputelement::HTMLInputElement;
 use crate::dom::htmloptionelement::HTMLOptionElement;
 use crate::dom::node::{window_from_node, Node, ShadowIncluding};
 use crate::dom::window::Window;
+use crate::dom::xmlserializer::XMLSerializer;
 use crate::script_thread::Documents;
 use cookie::Cookie;
 use euclid::{Point2D, Rect, Size2D};
@@ -281,6 +283,31 @@ pub fn handle_get_active_element(
         .unwrap();
 }
 
+pub fn handle_get_page_source(
+    documents: &Documents,
+    pipeline: PipelineId,
+    reply: IpcSender<Result<String, ()>>,
+) {
+    reply
+        .send(documents.find_document(pipeline).ok_or(()).and_then(|doc| {
+            match doc.GetDocumentElement() {
+                Some(elem) => match elem.GetOuterHTML() {
+                    Ok(source) => Ok(source.to_string()),
+                    Err(_) => {
+                        match XMLSerializer::new(doc.window())
+                            .SerializeToString(elem.upcast::<Node>())
+                        {
+                            Ok(source) => Ok(source.to_string()),
+                            Err(_) => Err(()),
+                        }
+                    },
+                },
+                None => Err(()),
+            }
+        }))
+        .unwrap();
+}
+
 pub fn handle_get_cookies(
     documents: &Documents,
     pipeline: PipelineId,

components/script_traits/webdriver_msg.rs

@@ -39,6 +39,7 @@ pub enum WebDriverScriptCommand {
     GetElementText(String, IpcSender<Result<String, ()>>),
     GetBrowsingContextId(WebDriverFrameId, IpcSender<Result<BrowsingContextId, ()>>),
     GetUrl(IpcSender<ServoUrl>),
+    GetPageSource(IpcSender<Result<String, ()>>),
     IsEnabled(String, IpcSender<Result<bool, ()>>),
     IsSelected(String, IpcSender<Result<bool, ()>>),
     GetTitle(IpcSender<String>),

components/webdriver_server/lib.rs

@@ -1188,6 +1188,23 @@ impl Handler {
         Ok(WebDriverResponse::Void)
     }
 
+    fn handle_get_page_source(&self) -> WebDriverResult<WebDriverResponse> {
+        let (sender, receiver) = ipc::channel().unwrap();
+
+        let cmd = WebDriverScriptCommand::GetPageSource(sender);
+        self.browsing_context_script_command(cmd)?;
+
+        match receiver.recv().unwrap() {
+            Ok(source) => Ok(WebDriverResponse::Generic(ValueResponse(
+                serde_json::to_value(source)?,
+            ))),
+            Err(_) => Err(WebDriverError::new(
+                ErrorStatus::UnknownError,
+                "Unknown error",
+            )),
+        }
+    }
+
     fn handle_execute_script(
         &self,
         parameters: &JavascriptCommandParameters,
@@ -1457,6 +1474,7 @@ impl WebDriverHandler<ServoExtensionRoute> for Handler {
             WebDriverCommand::GetCSSValue(ref element, ref name) => {
                 self.handle_element_css(element, name)
             },
+            WebDriverCommand::GetPageSource => self.handle_get_page_source(),
             WebDriverCommand::ExecuteScript(ref x) => self.handle_execute_script(x),
             WebDriverCommand::ExecuteAsyncScript(ref x) => self.handle_execute_async_script(x),
             WebDriverCommand::ElementSendKeys(ref element, ref keys) => {

tests/wpt/metadata/webdriver/tests/get_page_source/source.py.ini

@@ -1,2 +1,4 @@
 [source.py]
-  disabled: Unimplemented WebDriver command
+  [test_no_browsing_context]
+    expected: ERROR
+