Auto merge of #9055 - simartin:issue_9042, r=Wafflespeanut

Issue #9042: Report incorrect number of spaces around => in the style checker

Fixes https://github.com/servo/servo/issues/9042

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7 files changed, 48 insertions, 38 deletions

diff --git a/components/devtools/actors/network_event.rs b/components/devtools/actors/network_event.rs
index 317dc096157..eb77f174a9d 100644
--- a/components/devtools/actors/network_event.rs
+++ b/components/devtools/actors/network_event.rs
@@ -359,7 +359,7 @@ impl NetworkEventActor {
         let mut mString = "".to_owned();
         if let Some(ref headers) = self.response.headers {
             mString = match headers.get() {
-                Some(&ContentType(ref mime)) =>  mime.to_string(),
+                Some(&ContentType(ref mime)) => mime.to_string(),
                 None => "".to_owned()
             };
         }
@@ -377,7 +377,7 @@ impl NetworkEventActor {
         let mut cookies_size = 0;
         if let Some(ref headers) = self.response.headers {
             cookies_size = match headers.get() {
-                Some(&Cookie(ref cookie)) =>  cookie.len(),
+                Some(&Cookie(ref cookie)) => cookie.len(),
                 None => 0
             };
         }
@@ -408,7 +408,7 @@ impl NetworkEventActor {
         let mut cookies_size = 0;
         if let Some(ref headers) = self.response.headers {
             cookies_size = match headers.get() {
-                Some(&Cookie(ref cookie)) =>  cookie.len(),
+                Some(&Cookie(ref cookie)) => cookie.len(),
                 None => 0
             };
         }
diff --git a/components/gfx/paint_context.rs b/components/gfx/paint_context.rs
index 0000c62f0ca..1270071825d 100644
--- a/components/gfx/paint_context.rs
+++ b/components/gfx/paint_context.rs
@@ -1251,9 +1251,9 @@ impl<'a> PaintContext<'a> {
                                                             0.5 * border.bottom,
                                                             0.5 * border.left);
         let is_groove = match style {
-                border_style::T::groove =>  true,
-                border_style::T::ridge  =>  false,
-                _ =>  panic!("invalid border style")
+                border_style::T::groove => true,
+                border_style::T::ridge  => false,
+                _ => panic!("invalid border style")
         };
 
         let lighter_color;
diff --git a/components/layout/display_list_builder.rs b/components/layout/display_list_builder.rs
index 7370723a4df..7cc1d3f6311 100644
--- a/components/layout/display_list_builder.rs
+++ b/components/layout/display_list_builder.rs
@@ -1137,7 +1137,7 @@ impl FragmentDisplayListBuilding for Fragment {
                 if width > 0 && height > 0 {
                     let layer_id = self.layer_id();
                     let canvas_data = match canvas_fragment_info.ipc_renderer {
-                        Some(ref ipc_renderer) =>  {
+                        Some(ref ipc_renderer) => {
                             let ipc_renderer = ipc_renderer.lock().unwrap();
                             let (sender, receiver) = ipc::channel().unwrap();
                             ipc_renderer.send(CanvasMsg::FromLayout(
diff --git a/components/script/dom/document.rs b/components/script/dom/document.rs
index d1e529f3bfa..6fe811ef168 100644
--- a/components/script/dom/document.rs
+++ b/components/script/dom/document.rs
@@ -381,32 +381,32 @@ impl Document {
     pub fn set_encoding_name(&self, name: DOMString) {
         *self.encoding_name.borrow_mut() = DOMString::from(
             match name.as_ref() {
-                "utf-8"         =>  "UTF-8",
-                "ibm866"        =>  "IBM866",
-                "iso-8859-2"    =>  "ISO-8859-2",
-                "iso-8859-3"    =>  "ISO-8859-3",
-                "iso-8859-4"    =>  "ISO-8859-4",
-                "iso-8859-5"    =>  "ISO-8859-5",
-                "iso-8859-6"    =>  "ISO-8859-6",
-                "iso-8859-7"    =>  "ISO-8859-7",
-                "iso-8859-8"    =>  "ISO-8859-8",
-                "iso-8859-8-i"  =>  "ISO-8859-8-I",
-                "iso-8859-10"   =>  "ISO-8859-10",
-                "iso-8859-13"   =>  "ISO-8859-13",
-                "iso-8859-14"   =>  "ISO-8859-14",
-                "iso-8859-15"   =>  "ISO-8859-15",
-                "iso-8859-16"   =>  "ISO-8859-16",
-                "koi8-r"        =>  "KOI8-R",
-                "koi8-u"        =>  "KOI8-U",
-                "gbk"           =>  "GBK",
-                "big5"          =>  "Big5",
-                "euc-jp"        =>  "EUC-JP",
-                "iso-2022-jp"   =>  "ISO-2022-JP",
-                "shift_jis"     =>  "Shift_JIS",
-                "euc-kr"        =>  "EUC-KR",
-                "utf-16be"      =>  "UTF-16BE",
-                "utf-16le"      =>  "UTF-16LE",
-                _               =>  &*name
+                "utf-8"         => "UTF-8",
+                "ibm866"        => "IBM866",
+                "iso-8859-2"    => "ISO-8859-2",
+                "iso-8859-3"    => "ISO-8859-3",
+                "iso-8859-4"    => "ISO-8859-4",
+                "iso-8859-5"    => "ISO-8859-5",
+                "iso-8859-6"    => "ISO-8859-6",
+                "iso-8859-7"    => "ISO-8859-7",
+                "iso-8859-8"    => "ISO-8859-8",
+                "iso-8859-8-i"  => "ISO-8859-8-I",
+                "iso-8859-10"   => "ISO-8859-10",
+                "iso-8859-13"   => "ISO-8859-13",
+                "iso-8859-14"   => "ISO-8859-14",
+                "iso-8859-15"   => "ISO-8859-15",
+                "iso-8859-16"   => "ISO-8859-16",
+                "koi8-r"        => "KOI8-R",
+                "koi8-u"        => "KOI8-U",
+                "gbk"           => "GBK",
+                "big5"          => "Big5",
+                "euc-jp"        => "EUC-JP",
+                "iso-2022-jp"   => "ISO-2022-JP",
+                "shift_jis"     => "Shift_JIS",
+                "euc-kr"        => "EUC-KR",
+                "utf-16be"      => "UTF-16BE",
+                "utf-16le"      => "UTF-16LE",
+                _               => &*name
         });
     }
 
diff --git a/components/script/dom/htmlformelement.rs b/components/script/dom/htmlformelement.rs
index 6515eb58471..a8f9ce28db5 100644
--- a/components/script/dom/htmlformelement.rs
+++ b/components/script/dom/htmlformelement.rs
@@ -464,7 +464,7 @@ pub enum FormSubmittableElement {
 impl FormSubmittableElement {
     fn as_event_target(&self) -> &EventTarget {
         match *self {
-            FormSubmittableElement::ButtonElement(ref button) =>  button.r().upcast(),
+            FormSubmittableElement::ButtonElement(ref button) => button.r().upcast(),
             FormSubmittableElement::InputElement(ref input) => input.r().upcast(),
             FormSubmittableElement::ObjectElement(ref object) => object.r().upcast(),
             FormSubmittableElement::SelectElement(ref select) => select.r().upcast(),
diff --git a/components/util/debug_utils.rs b/components/util/debug_utils.rs
index 8c1954c78ba..631c7dad4ca 100644
--- a/components/util/debug_utils.rs
+++ b/components/util/debug_utils.rs
@@ -15,7 +15,7 @@ fn hexdump_slice(buf: &[u8]) {
         stderr.write_all(output.as_bytes()).unwrap();
         match i % 16 {
             15 => { stderr.write_all(b"\n    ").unwrap(); },
-            7 =>  { stderr.write_all(b"   ").unwrap(); },
+             7 => { stderr.write_all(b"   ").unwrap(); },
              _ => ()
         }
         stderr.flush().unwrap();
diff --git a/python/tidy.py b/python/tidy.py
index d974a89a1b8..d1a10522d4a 100644
--- a/python/tidy.py
+++ b/python/tidy.py
@@ -314,6 +314,16 @@ def check_rust(file_name, contents):
         if match:
             yield (idx + 1, "missing space after ->")
 
+        line_len = len(line)
+        arrow_pos = line.find("=>")
+        if arrow_pos != -1:
+            if arrow_pos and line[arrow_pos - 1] != ' ':
+                yield (idx + 1, "missing space before =>")
+            if arrow_pos + 2 < line_len and line[arrow_pos + 2] != ' ':
+                yield (idx + 1, "missing space after =>")
+            elif arrow_pos + 3 < line_len and line[arrow_pos + 3] == ' ':
+                yield (idx + 1, "extra space after =>")
+
         # Avoid flagging ::crate::mod and `trait Foo : Bar`
         match = line.find(" :")
         if match != -1:
@@ -344,7 +354,7 @@ def check_rust(file_name, contents):
         # check extern crates
         if line.startswith("extern crate "):
             crate_name = line[len("extern crate "):-1]
-            indent = len(original_line) - len(line)
+            indent = len(original_line) - line_len
             if indent not in prev_crate:
                 prev_crate[indent] = ""
             if prev_crate[indent] > crate_name:
@@ -358,7 +368,7 @@ def check_rust(file_name, contents):
         elif line.startswith("use "):
             import_block = True
             use = line[4:]
-            indent = len(original_line) - len(line)
+            indent = len(original_line) - line_len
             if not use.endswith(";"):
                 yield (idx + 1, "use statement spans multiple lines")
             current_use = use[:len(use) - 1]
@@ -378,7 +388,7 @@ def check_rust(file_name, contents):
 
         # modules must be in the same line and alphabetically sorted
         if line.startswith("mod ") or line.startswith("pub mod "):
-            indent = len(original_line) - len(line)
+            indent = len(original_line) - line_len
             mod = line[4:] if line.startswith("mod ") else line[8:]
 
             if idx < 0 or "#[macro_use]" not in contents[idx - 1]: