Auto merge of #6306 - metajack:shared-target-dir, r=mbrubeck

This speeds up `./mach build --dev` followed by `./mach build-cef` by
25%. When rust-lang/cargo#497 is fixed, this speedup will increase
dramatically.

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5 files changed, 16 insertions, 10 deletions

diff --git a/python/servo/build_commands.py b/python/servo/build_commands.py
index 6167431ac61..6fd44653603 100644
--- a/python/servo/build_commands.py
+++ b/python/servo/build_commands.py
@@ -147,7 +147,7 @@ class MachCommands(CommandBase):
         opts = params or []
         features = []
 
-        base_path = path.join("components", "servo", "target")
+        base_path = self.get_target_dir()
         release_path = path.join(base_path, "release", "servo")
         dev_path = path.join(base_path, "debug", "servo")
 
diff --git a/python/servo/command_base.py b/python/servo/command_base.py
index 5369b3e47f9..c6d46fc3de8 100644
--- a/python/servo/command_base.py
+++ b/python/servo/command_base.py
@@ -130,8 +130,14 @@ class CommandBase(object):
             self._cargo_build_id = open(filename).read().strip()
         return self._cargo_build_id
 
+    def get_target_dir(self):
+        if "CARGO_TARGET_DIR" in os.environ:
+            return os.environ["CARGO_TARGET_DIR"]
+        else:
+            return path.join(self.context.topdir, "target")
+
     def get_binary_path(self, release, dev):
-        base_path = path.join("components", "servo", "target")
+        base_path = self.get_target_dir()
         release_path = path.join(base_path, "release", "servo")
         dev_path = path.join(base_path, "debug", "servo")
 
@@ -199,6 +205,9 @@ class CommandBase(object):
         if "CARGO_HOME" not in env:
             env["CARGO_HOME"] = self.config["tools"]["cargo-home-dir"]
 
+        if "CARGO_TARGET_DIR" not in env:
+            env["CARGO_TARGET_DIR"] = path.join(self.context.topdir, "target")
+
         if extra_lib:
             if sys.platform == "darwin":
                 env["DYLD_LIBRARY_PATH"] = "%s%s%s" % \
diff --git a/python/servo/post_build_commands.py b/python/servo/post_build_commands.py
index 927b425efe8..efa315158f8 100644
--- a/python/servo/post_build_commands.py
+++ b/python/servo/post_build_commands.py
@@ -137,8 +137,7 @@ class MachCommands(CommandBase):
         if not path.exists(path.join(self.config["tools"]["rust-root"], "doc")):
             Registrar.dispatch("bootstrap-rust-docs", context=self.context)
         rust_docs = path.join(self.config["tools"]["rust-root"], "doc")
-        docs = path.join(
-            self.context.topdir, "components", "servo", "target", "doc")
+        docs = path.join(self.get_target_dir(), "doc")
         if not path.exists(docs):
             os.makedirs(docs)
 
@@ -167,4 +166,4 @@ class MachCommands(CommandBase):
         self.doc([])
         import webbrowser
         webbrowser.open("file://" + path.abspath(path.join(
-            self.servo_crate(), "target", "doc", "servo", "index.html")))
+            self.get_target_dir(), "doc", "servo", "index.html")))
diff --git a/python/servo/testing_commands.py b/python/servo/testing_commands.py
index 0daefd277b6..4d8a2e2778a 100644
--- a/python/servo/testing_commands.py
+++ b/python/servo/testing_commands.py
@@ -50,12 +50,11 @@ class MachCommands(CommandBase):
 
     def find_test(self, prefix):
         target_contents = os.listdir(path.join(
-            self.context.topdir, "components", "servo", "target", "debug"))
+            self.get_target_dir(), "debug"))
         for filename in target_contents:
             if filename.startswith(prefix + "-"):
                 filepath = path.join(
-                    self.context.topdir, "components", "servo",
-                    "target", "debug", filename)
+                    self.get_target_dir(), "debug", filename)
 
                 if path.isfile(filepath) and os.access(filepath, os.X_OK):
                     return filepath
diff --git a/python/tidy.py b/python/tidy.py
index 6f4dc9778e8..75b372995e1 100644
--- a/python/tidy.py
+++ b/python/tidy.py
@@ -36,8 +36,7 @@ ignored_files = [
     # Generated and upstream code combined with our own. Could use cleanup
     "components/script/dom/bindings/codegen/*",
     "components/style/properties/mod.rs",
-    "components/servo/target/*",
-    "ports/gonk/target/*",
+    "target/*",
     "ports/gonk/src/native_window_glue.cpp",
     "ports/cef/*",