Auto merge of #49 - servo:source-tarball-rust, r=larsbergstrom

Fix build script when the rustc commit date is unknown.

Hopefully fixes #44 (comment).

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Author: bors-servo

Cargo.toml

@@ -7,9 +7,6 @@ license = "MPL-2.0"
 repository = "https://github.com/servo/heapsize"
 build = "build.rs"
 
-[build-dependencies]
-regex = "0.1"
-
 [dependencies]
 kernel32-sys = "0.2.1"
 

build.rs

@@ -1,25 +1,36 @@
-extern crate regex;
-
 use std::env::var;
 use std::process::Command;
 use std::str;
 
 fn main() {
-    let version_line = Command::new(var("RUSTC").unwrap_or("rustc".into()))
+    let verbose = Command::new(var("RUSTC").unwrap_or("rustc".into()))
         .arg("--version")
+        .arg("--verbose")
         .output()
         .unwrap()
         .stdout;
-    let captures = regex::Regex::new(r"rustc (\d+)\.(\d+)\.(\d+).+(\d{4}-\d{2}-\d{2})\)")
-        .unwrap()
-        .captures(str::from_utf8(&version_line).unwrap())
-        .unwrap();
+    let verbose = str::from_utf8(&verbose).unwrap();
+    let mut commit_date = None;
+    let mut release = None;
+    for line in verbose.lines() {
+        let mut parts = line.split(':');
+        match parts.next().unwrap().trim() {
+            "commit-date" => commit_date = Some(parts.next().unwrap().trim()),
+            "release" => release = Some(parts.next().unwrap().trim()),
+            _ => {}
+        }
+    }
+    let version = release.unwrap().split('-').next().unwrap();;
+    let mut version_components = version.split('.').map(|s| s.parse::<u32>().unwrap());
     let version = (
-        captures[1].parse::<u32>().unwrap(),
-        captures[2].parse::<u32>().unwrap(),
-        captures[3].parse::<u32>().unwrap(),
-        &captures[4],
+        version_components.next().unwrap(),
+        version_components.next().unwrap(),
+        version_components.next().unwrap(),
+        // "unknown" sorts after "2016-02-14", which is what we want to defaut to unprefixed
+        // https://github.com/servo/heapsize/pull/44#issuecomment-187935883
+        commit_date.unwrap()
     );
+    assert_eq!(version_components.next(), None);
     if version < (1, 8, 0, "2016-02-14") {
         println!("cargo:rustc-cfg=prefixed_jemalloc");
     }