Auto merge of #12409 - Manishearth:clippy, r=nox

Update clippy, improve clippy integration

This makes it much easier to run rustfix on servo

(rustfix is still pretty buggy though)

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12 files changed, 43 insertions, 26 deletions

diff --git a/components/plugins/Cargo.toml b/components/plugins/Cargo.toml
index 331adbe5845..c60cc48b779 100644
--- a/components/plugins/Cargo.toml
+++ b/components/plugins/Cargo.toml
@@ -12,10 +12,10 @@ plugin = true
 [dependencies]
 tenacious = "0.2.0"
 
-[dependencies.clippy]
-git = "https://github.com/Manishearth/rust-clippy"
-rev = "9dca15de3e8ea266d3e7e868c0f358ed4fa5f195"
+[dependencies.clippy_lints]
+version = "0.0.77"
 optional = true
 
 [features]
 default = []
+clippy = ["clippy_lints"]
diff --git a/components/plugins/lib.rs b/components/plugins/lib.rs
index 9ee553145a5..52bfad7e049 100644
--- a/components/plugins/lib.rs
+++ b/components/plugins/lib.rs
@@ -18,7 +18,7 @@
 #![deny(unsafe_code)]
 
 #[cfg(feature = "clippy")]
-extern crate clippy;
+extern crate clippy_lints;
 #[macro_use]
 extern crate rustc;
 extern crate rustc_plugin;
@@ -44,12 +44,14 @@ mod utils;
 #[plugin_registrar]
 pub fn plugin_registrar(reg: &mut Registry) {
     reg.register_syntax_extension(intern("dom_struct"), MultiModifier(box jstraceable::expand_dom_struct));
-    reg.register_syntax_extension(intern("derive_JSTraceable"), MultiDecorator(box jstraceable::expand_jstraceable));
-    reg.register_syntax_extension(intern("_generate_reflector"), MultiDecorator(box reflector::expand_reflector));
-    reg.register_late_lint_pass(box lints::transmute_type::TransmutePass);
+    reg.register_syntax_extension(intern("derive_JSTraceable"),
+                                  MultiDecorator(box jstraceable::expand_jstraceable));
+    reg.register_syntax_extension(intern("_generate_reflector"),
+                                  MultiDecorator(box reflector::expand_reflector));
     reg.register_late_lint_pass(box lints::unrooted_must_root::UnrootedPass::new());
     reg.register_late_lint_pass(box lints::privatize::PrivatizePass);
     reg.register_late_lint_pass(box lints::inheritance_integrity::InheritancePass);
+    reg.register_late_lint_pass(box lints::transmute_type::TransmutePass);
     reg.register_early_lint_pass(box lints::ban::BanPass);
     reg.register_late_lint_pass(box tenacious::TenaciousPass);
     reg.register_attribute("must_root".to_string(), Whitelisted);
@@ -60,7 +62,7 @@ pub fn plugin_registrar(reg: &mut Registry) {
 
 #[cfg(feature = "clippy")]
 fn register_clippy(reg: &mut Registry) {
-    ::clippy::plugin_registrar(reg);
+    ::clippy_lints::register_plugins(reg);
 }
 #[cfg(not(feature = "clippy"))]
 fn register_clippy(_reg: &mut Registry) {
diff --git a/components/servo/Cargo.lock b/components/servo/Cargo.lock
index abcd86d8e07..6d293b3a476 100644
--- a/components/servo/Cargo.lock
+++ b/components/servo/Cargo.lock
@@ -2240,6 +2240,7 @@ dependencies = [
  "log 0.3.6 (registry+https://github.com/rust-lang/crates.io-index)",
  "matches 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "num-traits 0.1.32 (registry+https://github.com/rust-lang/crates.io-index)",
+ "plugins 0.0.1",
  "rand 0.3.14 (registry+https://github.com/rust-lang/crates.io-index)",
  "rustc-serialize 0.3.19 (registry+https://github.com/rust-lang/crates.io-index)",
  "selectors 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -2464,6 +2465,7 @@ dependencies = [
  "lazy_static 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "log 0.3.6 (registry+https://github.com/rust-lang/crates.io-index)",
  "num_cpus 0.2.13 (registry+https://github.com/rust-lang/crates.io-index)",
+ "plugins 0.0.1",
  "rustc-serialize 0.3.19 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde 0.7.11 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde_macros 0.7.11 (registry+https://github.com/rust-lang/crates.io-index)",
diff --git a/components/style/Cargo.toml b/components/style/Cargo.toml
index 049dd560eeb..d20d529b93b 100644
--- a/components/style/Cargo.toml
+++ b/components/style/Cargo.toml
@@ -16,7 +16,7 @@ servo = ["serde", "serde/nightly", "serde_macros", "heapsize", "heapsize_plugin"
          "style_traits/servo", "app_units/plugins", "euclid/plugins",
          "cssparser/heap_size", "cssparser/serde-serialization",
          "selectors/heap_size", "selectors/unstable", "string_cache/heap_size",
-         "url/heap_size"]
+         "url/heap_size", "plugins"]
 
 [dependencies]
 app_units = "0.2.5"
@@ -45,6 +45,7 @@ style_traits = {path = "../style_traits"}
 time = "0.1"
 url = "1.0.0"
 util = {path = "../util"}
+plugins = {path = "../plugins", optional = true}
 
 [target.'cfg(windows)'.dependencies]
 kernel32-sys = "0.2"
diff --git a/components/style/attr.rs b/components/style/attr.rs
index 409f6bdbd56..6ca278d7d2c 100644
--- a/components/style/attr.rs
+++ b/components/style/attr.rs
@@ -490,7 +490,7 @@ pub fn parse_length(mut value: &str) -> LengthOrPercentageOrAuto {
     }
 
     // Step 5
-    if value.starts_with("+") {
+    if value.starts_with('+') {
         value = &value[1..]
     }
 
diff --git a/components/style/custom_properties.rs b/components/style/custom_properties.rs
index db7316fa0c0..5a7109f77ac 100644
--- a/components/style/custom_properties.rs
+++ b/components/style/custom_properties.rs
@@ -194,7 +194,7 @@ fn parse_declaration_value_block(input: &mut Parser,
                 let token_slice = input.slice_from(token_start);
                 if !token_slice.ends_with("*/") {
                     missing_closing_characters.push_str(
-                        if token_slice.ends_with("*") { "/" } else { "*/" })
+                        if token_slice.ends_with('*') { "/" } else { "*/" })
                 }
                 token.serialization_type()
             }
diff --git a/components/style/lib.rs b/components/style/lib.rs
index d92524c8877..813a24af14e 100644
--- a/components/style/lib.rs
+++ b/components/style/lib.rs
@@ -27,6 +27,7 @@
 #![cfg_attr(feature = "servo", feature(custom_derive))]
 #![cfg_attr(feature = "servo", feature(plugin))]
 #![cfg_attr(feature = "servo", plugin(heapsize_plugin))]
+#![cfg_attr(feature = "servo", plugin(plugins))]
 #![cfg_attr(feature = "servo", plugin(serde_macros))]
 
 #![deny(unsafe_code)]
diff --git a/components/style/matching.rs b/components/style/matching.rs
index 251d46d70b6..194e58907fb 100644
--- a/components/style/matching.rs
+++ b/components/style/matching.rs
@@ -602,17 +602,14 @@ pub trait ElementMatchMethods : TElement
         }
 
         for (i, &(ref candidate, ())) in style_sharing_candidate_cache.iter().enumerate() {
-            match self.share_style_with_candidate_if_possible(parent.clone(), candidate) {
-                Some(shared_style) => {
-                    // Yay, cache hit. Share the style.
-                    let node = self.as_node();
-                    let style = &mut node.mutate_data().unwrap().style;
-                    let damage = <<Self as TElement>::ConcreteNode as TNode>
-                                     ::ConcreteRestyleDamage::compute((*style).as_ref(), &*shared_style);
-                    *style = Some(shared_style);
-                    return StyleSharingResult::StyleWasShared(i, damage)
-                }
-                None => {}
+            if let Some(shared_style) = self.share_style_with_candidate_if_possible(parent.clone(), candidate) {
+                // Yay, cache hit. Share the style.
+                let node = self.as_node();
+                let style = &mut node.mutate_data().unwrap().style;
+                let damage = <<Self as TElement>::ConcreteNode as TNode>
+                                 ::ConcreteRestyleDamage::compute((*style).as_ref(), &*shared_style);
+                *style = Some(shared_style);
+                return StyleSharingResult::StyleWasShared(i, damage)
             }
         }
 
diff --git a/components/util/Cargo.toml b/components/util/Cargo.toml
index 3a9478a49b3..b9954763d24 100644
--- a/components/util/Cargo.toml
+++ b/components/util/Cargo.toml
@@ -11,7 +11,7 @@ path = "lib.rs"
 [features]
 # servo as opposed to geckolib
 servo = ["serde", "serde_macros", "backtrace", "ipc-channel", "app_units/plugins",
-         "euclid/plugins", "euclid/unstable", "url/heap_size", "url/serde"]
+         "euclid/plugins", "euclid/unstable", "url/heap_size", "url/serde", "plugins"]
 
 [dependencies]
 app_units = "0.2.5"
@@ -28,6 +28,7 @@ rustc-serialize = "0.3"
 serde = {version = "0.7.11", optional = true}
 serde_macros = {version = "0.7.11", optional = true}
 url = "1.0.0"
+plugins = {path = "../plugins", optional = true}
 
 [target.'cfg(all(unix, not(target_os = "macos"), not(target_os = "ios"), not(target_os = "android")))'.dependencies]
 xdg = "2.0"
diff --git a/components/util/lib.rs b/components/util/lib.rs
index 2e57d5a5f4b..6b906f83c8d 100644
--- a/components/util/lib.rs
+++ b/components/util/lib.rs
@@ -7,6 +7,7 @@
 #![cfg_attr(feature = "servo", feature(plugin))]
 #![cfg_attr(feature = "servo", feature(reflect_marker))]
 #![cfg_attr(feature = "servo", plugin(serde_macros))]
+#![cfg_attr(feature = "servo", plugin(plugins))]
 
 #![deny(unsafe_code)]
 
diff --git a/ports/cef/Cargo.lock b/ports/cef/Cargo.lock
index 443ca6ec95d..1cdd57c7f1e 100644
--- a/ports/cef/Cargo.lock
+++ b/ports/cef/Cargo.lock
@@ -2125,6 +2125,7 @@ dependencies = [
  "log 0.3.6 (registry+https://github.com/rust-lang/crates.io-index)",
  "matches 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
  "num-traits 0.1.32 (registry+https://github.com/rust-lang/crates.io-index)",
+ "plugins 0.0.1",
  "rand 0.3.14 (registry+https://github.com/rust-lang/crates.io-index)",
  "rustc-serialize 0.3.19 (registry+https://github.com/rust-lang/crates.io-index)",
  "selectors 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -2333,6 +2334,7 @@ dependencies = [
  "lazy_static 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "log 0.3.6 (registry+https://github.com/rust-lang/crates.io-index)",
  "num_cpus 0.2.13 (registry+https://github.com/rust-lang/crates.io-index)",
+ "plugins 0.0.1",
  "rustc-serialize 0.3.19 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde 0.7.11 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde_macros 0.7.11 (registry+https://github.com/rust-lang/crates.io-index)",
diff --git a/python/servo/devenv_commands.py b/python/servo/devenv_commands.py
index 2619827c226..a4bfa5c5df1 100644
--- a/python/servo/devenv_commands.py
+++ b/python/servo/devenv_commands.py
@@ -94,11 +94,21 @@ class MachCommands(CommandBase):
     @Command('clippy',
              description='Run Clippy',
              category='devenv')
-    def clippy(self):
-        features = "--features=script/plugins/clippy"
+    @CommandArgument(
+        '--package', '-p', default=None,
+        help='Updates the selected package')
+    @CommandArgument(
+        '--json', '-j', action="store_true",
+        help='Outputs')
+    def clippy(self, package=None, json=False):
+        params = ["--features=script/plugins/clippy"]
+        if package:
+            params += ["-p", package]
+        if json:
+            params += ["--", "-Zunstable-options", "--error-format", "json"]
 
         with cd(path.join(self.context.topdir, "components", "servo")):
-            return subprocess.call(["cargo", "build", features],
+            return subprocess.call(["cargo", "rustc", "-v"] + params,
                                    env=self.build_env())
 
     @Command('rustc',