Auto merge of #8622 - frewsxcv:url-plugin, r=SimonSapin

Implement 'url!(..)' macro

https://github.com/servo/rust-url/issues/136

https://github.com/servo/rust-url/pull/137

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13 files changed, 171 insertions, 8 deletions

diff --git a/components/compositing/constellation.rs b/components/compositing/constellation.rs
index 2084ace9701..1055aabaa26 100644
--- a/components/compositing/constellation.rs
+++ b/components/compositing/constellation.rs
@@ -701,7 +701,7 @@ impl<LTF: LayoutTaskFactory, STF: ScriptTaskFactory> Constellation<LTF, STF> {
                           parent_info,
                           window_size,
                           None,
-                          LoadData::new(Url::parse("about:failure").unwrap()));
+                          LoadData::new(url!("about:failure")));
 
         self.push_pending_frame(new_pipeline_id, Some(pipeline_id));
     }
diff --git a/components/plugins/Cargo.toml b/components/plugins/Cargo.toml
index 9e317316984..f697fe45cf7 100644
--- a/components/plugins/Cargo.toml
+++ b/components/plugins/Cargo.toml
@@ -16,5 +16,8 @@ git = "https://github.com/Manishearth/rust-clippy"
 branch = "servo"
 optional = true
 
+[dependencies.url]
+version = "0.2.36"
+
 [features]
 default = []
diff --git a/components/plugins/lib.rs b/components/plugins/lib.rs
index bb328c9441a..d52ad866879 100644
--- a/components/plugins/lib.rs
+++ b/components/plugins/lib.rs
@@ -26,6 +26,8 @@ extern crate tenacious;
 #[cfg(feature = "clippy")]
 extern crate clippy;
 
+extern crate url;
+
 use rustc::plugin::Registry;
 use syntax::ext::base::*;
 use syntax::feature_gate::AttributeType::Whitelisted;
@@ -41,6 +43,7 @@ pub mod lints;
 pub mod reflector;
 /// Utilities for writing plugins
 pub mod casing;
+mod url_plugin;
 pub mod utils;
 
 #[plugin_registrar]
@@ -51,6 +54,7 @@ pub fn plugin_registrar(reg: &mut Registry) {
     reg.register_syntax_extension(intern("derive_HeapSizeOf"), MultiDecorator(box heap_size::expand_heap_size));
     reg.register_macro("to_lower", casing::expand_lower);
     reg.register_macro("to_upper", casing::expand_upper);
+    reg.register_macro("url", url_plugin::expand_url);
     reg.register_late_lint_pass(box lints::transmute_type::TransmutePass);
     reg.register_late_lint_pass(box lints::unrooted_must_root::UnrootedPass::new());
     reg.register_late_lint_pass(box lints::privatize::PrivatizePass);
diff --git a/components/plugins/url_plugin.rs b/components/plugins/url_plugin.rs
new file mode 100644
index 00000000000..8ae06624c4b
--- /dev/null
+++ b/components/plugins/url_plugin.rs
@@ -0,0 +1,141 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+use std::error::Error;
+use syntax;
+use syntax::ast::{TokenTree, ExprLit, LitStr, Expr};
+use syntax::codemap::Span;
+use syntax::ext::base::{ExtCtxt, MacResult, MacEager, DummyResult};
+use syntax::ext::build::AstBuilder;
+use syntax::fold::Folder;
+use syntax::parse;
+use syntax::parse::token::InternedString;
+use url::{Url, Host, RelativeSchemeData, SchemeData};
+
+pub fn expand_url(cx: &mut ExtCtxt, sp: Span, tts: &[TokenTree])
+        -> Box<MacResult + 'static> {
+    let mut parser = parse::new_parser_from_tts(cx.parse_sess(), cx.cfg(), tts.to_vec());
+    let query_expr = cx.expander().fold_expr(parser.parse_expr());
+
+    // Ensure a str literal was passed to the macro
+    let query = match parse_str_lit(&query_expr) {
+        Some(query) => query,
+        None => {
+            cx.span_err(query_expr.span, "'url!' expected string literal");
+            return DummyResult::any(sp)
+        },
+    };
+
+    // Parse the str literal
+    let Url { scheme, scheme_data, query, fragment } = match Url::parse(&query) {
+        Ok(url) => url,
+        Err(error) => {
+            cx.span_err(query_expr.span, error.description());
+            return DummyResult::any(sp)
+        }
+    };
+
+    let scheme_data_expr = cx.expr_scheme_data(sp, scheme_data);
+    let query_expr = cx.expr_option_string(sp, query);
+    let fragment_expr = cx.expr_option_string(sp, fragment);
+
+    let url_expr = quote_expr!(cx, {
+        ::url::Url {
+            scheme: $scheme.to_owned(),
+            scheme_data: $scheme_data_expr,
+            query: $query_expr,
+            fragment: $fragment_expr,
+        }
+    });
+
+    MacEager::expr(url_expr)
+}
+
+fn parse_str_lit(e: &Expr) -> Option<InternedString> {
+    if let ExprLit(ref lit) = e.node {
+        if let LitStr(ref s, _) = lit.node {
+            return Some(s.clone());
+        }
+    }
+    None
+}
+
+trait ExtCtxtHelpers {
+    fn expr_scheme_data(&self, sp: Span, scheme_data: SchemeData) -> syntax::ptr::P<Expr>;
+    fn expr_option_string(&self, sp: Span, string: Option<String>) -> syntax::ptr::P<Expr>;
+    fn expr_option_u16(&self, sp: Span, unsigned: Option<u16>) -> syntax::ptr::P<Expr>;
+    fn expr_host(&self, sp: Span, host: Host) -> syntax::ptr::P<Expr>;
+    fn expr_slice_u16(&self, sp: Span, unsigned: &[u16]) -> syntax::ptr::P<Expr>;
+    fn expr_vec_string(&self, sp: Span, strings: Vec<String>) -> syntax::ptr::P<Expr>;
+}
+
+impl<'a> ExtCtxtHelpers for ExtCtxt<'a> {
+    fn expr_scheme_data(&self, sp: Span, scheme_data: SchemeData) -> syntax::ptr::P<Expr> {
+        match scheme_data {
+            SchemeData::Relative(
+                RelativeSchemeData { username, password, host, port, default_port, path }) =>
+            {
+                let password_expr = self.expr_option_string(sp, password);
+                let host_expr = self.expr_host(sp, host);
+                let port_expr = self.expr_option_u16(sp, port);
+                let default_port_expr = self.expr_option_u16(sp, default_port);
+                let path_expr = self.expr_vec_string(sp, path);
+
+                quote_expr!(self,
+                            ::url::SchemeData::Relative(
+                                ::url::RelativeSchemeData {
+                                    username: $username.to_owned(),
+                                    password: $password_expr,
+                                    host: $host_expr,
+                                    port: $port_expr,
+                                    default_port: $default_port_expr,
+                                    path: $path_expr.to_owned(),
+                                }
+                            ))
+            },
+            SchemeData::NonRelative(ref scheme_data) => {
+                quote_expr!(self, ::url::SchemeData::NonRelative($scheme_data.to_owned()))
+            },
+        }
+    }
+
+    fn expr_option_string(&self, sp: Span, string: Option<String>) -> syntax::ptr::P<Expr> {
+        match string {
+            Some(string) => quote_expr!(self, Some($string.to_owned())),
+            None => self.expr_none(sp),
+        }
+    }
+
+    fn expr_option_u16(&self, sp: Span, unsigned: Option<u16>) -> syntax::ptr::P<Expr> {
+        match unsigned {
+            Some(unsigned) => quote_expr!(self, Some($unsigned)),
+            None => self.expr_none(sp),
+        }
+    }
+
+    fn expr_host(&self, sp: Span, host: Host) -> syntax::ptr::P<Expr> {
+        match host {
+            Host::Domain(domain) => quote_expr!(self, ::url::Host::Domain(String::from($domain))),
+            Host::Ipv6(address) => {
+                let pieces_expr = self.expr_slice_u16(sp, &address.pieces);
+                quote_expr!(self,
+                            ::url::Host::Ipv6(
+                                ::url::Ipv6Address {
+                                    pieces: $pieces_expr.to_owned()
+                                }
+                            ))
+            },
+        }
+    }
+
+    fn expr_slice_u16(&self, sp: Span, unsigned: &[u16]) -> syntax::ptr::P<Expr> {
+        let unsigned = unsigned.iter().map(|p| quote_expr!(self, $p)).collect();
+        self.expr_vec_slice(sp, unsigned)
+    }
+
+    fn expr_vec_string(&self, sp: Span, strings: Vec<String>) -> syntax::ptr::P<Expr> {
+        let strings = strings.iter().map(|p| quote_expr!(self, $p.to_owned())).collect();
+        self.expr_vec(sp, strings)
+    }
+}
diff --git a/components/script/dom/document.rs b/components/script/dom/document.rs
index 585b93f1912..34a7846b543 100644
--- a/components/script/dom/document.rs
+++ b/components/script/dom/document.rs
@@ -1388,7 +1388,7 @@ impl Document {
                      source: DocumentSource,
                      doc_loader: DocumentLoader)
                      -> Document {
-        let url = url.unwrap_or_else(|| Url::parse("about:blank").unwrap());
+        let url = url.unwrap_or_else(|| url!("about:blank"));
 
         let (ready_state, domcontentloaded_dispatched) = if source == DocumentSource::FromParser {
             (DocumentReadyState::Loading, false)
diff --git a/components/script/dom/htmliframeelement.rs b/components/script/dom/htmliframeelement.rs
index b3e62ef434b..7d14dfe916d 100644
--- a/components/script/dom/htmliframeelement.rs
+++ b/components/script/dom/htmliframeelement.rs
@@ -124,7 +124,7 @@ impl HTMLIFrameElement {
     pub fn process_the_iframe_attributes(&self) {
         let url = match self.get_url() {
             Some(url) => url.clone(),
-            None => Url::parse("about:blank").unwrap(),
+            None => url!("about:blank"),
         };
 
         self.navigate_child_browsing_context(url);
diff --git a/components/script/script_task.rs b/components/script/script_task.rs
index 1f407ab940a..95e1c7f356f 100644
--- a/components/script/script_task.rs
+++ b/components/script/script_task.rs
@@ -1969,7 +1969,7 @@ impl ScriptTask {
         };
 
         if load_data.url.scheme == "javascript" {
-            load_data.url = Url::parse("about:blank").unwrap();
+            load_data.url = url!("about:blank");
         }
 
         resource_task.send(ControlMsg::Load(NetLoadData {
diff --git a/components/servo/Cargo.lock b/components/servo/Cargo.lock
index 92b083fdf50..b95310c217a 100644
--- a/components/servo/Cargo.lock
+++ b/components/servo/Cargo.lock
@@ -28,6 +28,7 @@ dependencies = [
  "net_traits 0.0.1",
  "net_traits_tests 0.0.1",
  "offscreen_gl_context 0.1.0 (git+https://github.com/ecoal95/rust-offscreen-rendering-context)",
+ "plugin_tests 0.0.1",
  "profile 0.0.1",
  "profile_traits 0.0.1",
  "script 0.0.1",
@@ -1223,6 +1224,7 @@ dependencies = [
  "msg 0.0.1",
  "net 0.0.1",
  "net_traits 0.0.1",
+ "plugins 0.0.1",
  "time 0.1.32 (registry+https://github.com/rust-lang/crates.io-index)",
  "url 0.2.37 (registry+https://github.com/rust-lang/crates.io-index)",
  "util 0.0.1",
@@ -1389,10 +1391,19 @@ version = "0.3.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
+name = "plugin_tests"
+version = "0.0.1"
+dependencies = [
+ "plugins 0.0.1",
+ "url 0.2.37 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
 name = "plugins"
 version = "0.0.1"
 dependencies = [
  "tenacious 0.0.11 (git+https://github.com/Manishearth/rust-tenacious)",
+ "url 0.2.37 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
 
 [[package]]
@@ -1770,6 +1781,7 @@ dependencies = [
  "app_units 0.1.3 (registry+https://github.com/rust-lang/crates.io-index)",
  "cssparser 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "euclid 0.3.2 (registry+https://github.com/rust-lang/crates.io-index)",
+ "plugins 0.0.1",
  "selectors 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)",
  "string_cache 0.1.17 (registry+https://github.com/rust-lang/crates.io-index)",
  "string_cache_plugin 0.1.9 (registry+https://github.com/rust-lang/crates.io-index)",
diff --git a/components/servo/Cargo.toml b/components/servo/Cargo.toml
index b17a137a16c..5d2222b8aa1 100644
--- a/components/servo/Cargo.toml
+++ b/components/servo/Cargo.toml
@@ -29,6 +29,9 @@ path = "../../tests/unit/net"
 [dev-dependencies.net_traits_tests]
 path = "../../tests/unit/net_traits"
 
+[dev-dependencies.plugin_tests]
+path = "../../tests/unit/plugin"
+
 [dev-dependencies.script_tests]
 path = "../../tests/unit/script"
 
diff --git a/components/style/font_face.rs b/components/style/font_face.rs
index ff4f2993d81..52abb82c3cf 100644
--- a/components/style/font_face.rs
+++ b/components/style/font_face.rs
@@ -112,7 +112,7 @@ fn parse_one_src(context: &ParserContext, input: &mut Parser) -> Result<Source,
     }
     let url = try!(input.expect_url());
     let url = UrlParser::new().base_url(context.base_url).parse(&url).unwrap_or_else(
-        |_error| Url::parse("about:invalid").unwrap());
+        |_error| url!("about:invalid"));
 
     // Parsing optional format()
     let format_hints = if input.try(|input| input.expect_function_matching("format")).is_ok() {
diff --git a/components/style/parser.rs b/components/style/parser.rs
index f189c7c5d93..67f35fa0976 100644
--- a/components/style/parser.rs
+++ b/components/style/parser.rs
@@ -31,7 +31,7 @@ impl<'a> ParserContext<'a> {
 impl<'a> ParserContext<'a> {
     pub fn parse_url(&self, input: &str) -> Url {
         UrlParser::new().base_url(self.base_url).parse(input)
-            .unwrap_or_else(|_| Url::parse("about:invalid").unwrap())
+            .unwrap_or_else(|_| url!("about:invalid"))
     }
 }
 
diff --git a/components/style/selector_matching.rs b/components/style/selector_matching.rs
index e8887163b61..f4b2168fc26 100644
--- a/components/style/selector_matching.rs
+++ b/components/style/selector_matching.rs
@@ -61,7 +61,7 @@ lazy_static! {
             Ok(res) => {
                 Stylesheet::from_bytes(
                     &res,
-                    Url::parse("chrome:///quirks-mode.css").unwrap(),
+                    url!("chrome:///quirks-mode.css"),
                     None,
                     None,
                     Origin::UserAgent)
diff --git a/components/util/opts.rs b/components/util/opts.rs
index 761568de42d..1b74e142408 100644
--- a/components/util/opts.rs
+++ b/components/util/opts.rs
@@ -440,7 +440,7 @@ const DEFAULT_USER_AGENT: UserAgent = UserAgent::Desktop;
 pub fn default_opts() -> Opts {
     Opts {
         is_running_problem_test: false,
-        url: Some(Url::parse("about:blank").unwrap()),
+        url: Some(url!("about:blank")),
         paint_threads: 1,
         gpu_painting: false,
         tile_size: 512,