Generate compile_commands.json on MacOS with Clang

gen_compiledb.py

#!/usr/bin/env python3
# Configures the build to use XCode targeting macOS
import json
import os
import os.path
import string
import subprocess
import sys


def exit_with_error(err_str):
    """print error in red and exit."""
    print("\033[91mERROR: %s\033[0m" % (err_str))
    sys.exit(1)

def print_ok(err_str):
    """print ok message in green."""
    print("\033[92m%s\033[0m" % (err_str))


def setup_icecream():
    """Do setup"""

    brew_cmd = "/usr/local/bin/brew"

    # Step 1 - check for brew
    if not os.path.exists(brew_cmd):
        exit_with_error("Homebrew was not found at %s, please install homebrew at http://brew.sh" % (brew_cmd))

    # Step 2 - check version of icecream
    try:
        icecream_js = subprocess.check_output([brew_cmd, "info", "--json=v1", "llvm"]).decode('utf-8')
    except subprocess.CalledProcessError:
        exit_with_error("icecream is not installed, please install icecream with 'brew install llvm'")

    # Step 3 - Find the version
    icecc_js = json.loads(icecream_js)

    # Step 3.1 - Try grabbing linked_key first.
    # If icecream is not linked, it comes back as "null" from brew, without the quotes
    # TODO - verify how versions sort
    icecream_version =  icecc_js[0]["installed"][0]["version"]

    #CC = subprocess.check_output(['xcrun', '-f', '--sdk', 'macosx', 'clang']).decode('utf-8').strip()
    #CXX = subprocess.check_output(['xcrun', '-f', '--sdk', 'macosx', 'clang++']).decode('utf-8').strip()

    CC = "/usr/local/Cellar/llvm/{}/bin/clang".format(icecream_version)
    CXX = "/usr/local/Cellar/llvm/{}/bin/clang++".format(icecream_version)

    sdk_path = subprocess.check_output(['xcrun', '--sdk', 'macosx', '--show-sdk-path']).decode('utf-8').strip()

        # TODO - verify c++ include dir path
    CCFLAGS = "-isysroot {} -isystem /usr/local/Cellar/llvm/{}/include/c++/v1 -mmacosx-version-min=10.12 -target darwin16.0.0 -arch x86_64".format(sdk_path, icecream_version)

    subprocess.check_call(["python3", "buildscripts/scons.py", "CC="+CC, "CXX="+CXX, "CCFLAGS="+CCFLAGS, "compiledb", "generated-sources"])

    print_ok("Icecream setup with launchctl complete. Happy Building!")
    print("\nIcecream will now be run as the current user on login.")
    print("To stop, run launchctl stop com.mongodb.iceccd")
    return

if __name__ == "__main__":
    setup_icecream()