Auto merge of #302 - fitzgen:bindings-all, r=Ms2ger

Add the `etc/bindings-all.py` script to orchestrate bindings generation

The `bindings-all.py` script will make sure that you don't accidentally try and use DEBUG bindings for a non-DEBUG build or vice-versa. It orchestrates all of building, regenerating and testing new SpiderMonkey bindings.

Running this script on fedora regenerates the linux_64 bindings exactly as they are on the smup branch for me. I think this is a large usability improvement over what we do now.

r? @Ms2ger @nox

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Author: bors-servo

etc/bindings-all.py

@@ -0,0 +1,82 @@
+#!/usr/bin/env python3
+
+import os, subprocess, sys
+
+def usage_and_exit():
+    print("")
+    print("Usage:")
+    print("    bindings-all.py <platform> <bindgen> <clang_lib_path>")
+    print("")
+    print("    Regenerates both debugmozjs and non-debugmozjs bindings and")
+    print("    tests them.")
+    print("")
+    print("    <platform>         One of 'linux_32', 'linux_64', 'macos_64',")
+    print("                       'windows_gcc_64', or 'windows_msvc14_64'.")
+    print("")
+    print("    <bindgen>          The path to bindgen")
+    print("")
+    print("    <clang_lib_path>   The path to the directory of clang library files")
+    sys.exit(1)
+
+# Validate arguments.
+
+if len(sys.argv) != 4:
+    usage_and_exit()
+
+[platform, bindgen, clang_lib_path] = sys.argv[1:]
+
+try:
+    ["linux_32", "linux_64", "macos_64", "windows_gcc_64", "windows_msvc14_64"].index(platform)
+except ValueError:
+    print("error: {} is not a valid platform".format(platform))
+    usage_and_exit()
+
+bindgen = os.path.abspath(bindgen)
+if not (os.path.isfile(bindgen) and os.access(bindgen, os.X_OK)):
+    print("error: {} is not executable".format(bindgen))
+    usage_and_exit()
+
+clang_lib_path = os.path.abspath(clang_lib_path)
+if not os.path.isdir(clang_lib_path):
+    print("error: {} is not a directory".format(bindgen))
+
+# Go to the root of our repo.
+os.chdir(os.path.dirname(sys.argv[0]))
+os.chdir("..")
+
+def run(cmd, **kwargs):
+    """Run the given shell command.
+
+    Pass through kwargs (like env=...) to `subprocess.Popen`. Wait for the
+    subprocess to complete, and throw an exception if it didn't exit with 0.
+
+    """
+    print("{}: Running".format(sys.argv[0]), cmd)
+    proc = subprocess.Popen(cmd, **kwargs)
+    proc.wait()
+    if proc.returncode != 0:
+        raise subprocess.CalledProcessError(proc.returncode, cmd)
+
+# Set up the environment needed to run bindgen.
+bindgen_env = os.environ.copy()
+bindgen_env["LIBCLANG_PATH"] = clang_lib_path
+if platform.startswith("macos"):
+    bindgen_env["DYLD_LIBRARY_PATH"] = clang_lib_path
+else:
+    bindgen_env["LD_LIBRARY_PATH"] = clang_lib_path
+
+# Run our builds.
+
+BUILDS = [
+    # Release build
+    ("", []),
+    # DEBUG build
+    ("_debug", ["--features", "debugmozjs"])
+]
+
+for (build_modifier, extra_cargo_flags) in BUILDS:
+    run(["cargo", "clean"])
+    run(["cargo", "build", "-p", "mozjs_sys"] + extra_cargo_flags)
+    run(["./etc/bindings.sh"], env=bindgen_env)
+    run(["mv", "out.rs", "src/jsapi_{}{}.rs".format(platform, build_modifier)])
+    run(["cargo", "test"] + extra_cargo_flags)