Auto merge of #8685 - jmr0:master, r=Ms2ger

tidy rule to warn against use of &String and refactoring

Fixes #8681

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4 files changed, 11 insertions, 7 deletions

diff --git a/components/net/mime_classifier.rs b/components/net/mime_classifier.rs
index 948425890e3..29f559a4738 100644
--- a/components/net/mime_classifier.rs
+++ b/components/net/mime_classifier.rs
@@ -129,8 +129,8 @@ impl MIMEClassifier {
         }
     }
 
-    fn get_media_type(media_type: &String,
-                          media_subtype: &String) -> Option<MediaType> {
+    fn get_media_type(media_type: &str,
+                          media_subtype: &str) -> Option<MediaType> {
         if MIMEClassifier::is_xml(media_type, media_subtype) {
             Some(MediaType::Xml)
         } else if MIMEClassifier::is_html(media_type, media_subtype) {
diff --git a/components/profile/mem.rs b/components/profile/mem.rs
index 0bd91f7afed..becd2d05554 100644
--- a/components/profile/mem.rs
+++ b/components/profile/mem.rs
@@ -225,7 +225,7 @@ impl ReportsTree {
 
     // Searches the tree's children for a path_seg match, and returns the index if there is a
     // match.
-    fn find_child(&self, path_seg: &String) -> Option<usize> {
+    fn find_child(&self, path_seg: &str) -> Option<usize> {
         for (i, child) in self.children.iter().enumerate() {
             if child.path_seg == *path_seg {
                 return Some(i);
diff --git a/components/webdriver_server/lib.rs b/components/webdriver_server/lib.rs
index 9bad724d164..22acb46d52d 100644
--- a/components/webdriver_server/lib.rs
+++ b/components/webdriver_server/lib.rs
@@ -525,11 +525,11 @@ impl Handler {
         }
     }
 
-    fn handle_element_attribute(&self, element: &WebElement, name: &String) -> WebDriverResult<WebDriverResponse> {
+    fn handle_element_attribute(&self, element: &WebElement, name: &str) -> WebDriverResult<WebDriverResponse> {
         let pipeline_id = try!(self.frame_pipeline());
 
         let (sender, receiver) = ipc::channel().unwrap();
-        let cmd = WebDriverScriptCommand::GetElementAttribute(element.id.clone(), name.clone(), sender);
+        let cmd = WebDriverScriptCommand::GetElementAttribute(element.id.clone(), name.to_owned(), sender);
         let cmd_msg = WebDriverCommandMsg::ScriptCommand(pipeline_id, cmd);
         self.constellation_chan.send(ConstellationMsg::WebDriverCommand(cmd_msg)).unwrap();
         match receiver.recv().unwrap() {
@@ -539,11 +539,11 @@ impl Handler {
         }
     }
 
-    fn handle_element_css(&self, element: &WebElement, name: &String) -> WebDriverResult<WebDriverResponse> {
+    fn handle_element_css(&self, element: &WebElement, name: &str) -> WebDriverResult<WebDriverResponse> {
         let pipeline_id = try!(self.frame_pipeline());
 
         let (sender, receiver) = ipc::channel().unwrap();
-        let cmd = WebDriverScriptCommand::GetElementCSS(element.id.clone(), name.clone(), sender);
+        let cmd = WebDriverScriptCommand::GetElementCSS(element.id.clone(), name.to_owned(), sender);
         let cmd_msg = WebDriverCommandMsg::ScriptCommand(pipeline_id, cmd);
         self.constellation_chan.send(ConstellationMsg::WebDriverCommand(cmd_msg)).unwrap();
         match receiver.recv().unwrap() {
diff --git a/python/tidy.py b/python/tidy.py
index dd2ef9d29cc..499fb8c5efc 100644
--- a/python/tidy.py
+++ b/python/tidy.py
@@ -369,6 +369,10 @@ def check_rust(file_name, contents):
         if ": &Vec<" in line:
             yield (idx + 1, "use &[T] instead of &Vec<T>")
 
+        # No benefit over using &str
+        if ": &String" in line:
+            yield (idx + 1, "use &str instead of &String")
+
 
 # Avoid flagging <Item=Foo> constructs
 def is_associated_type(match, line, index):