Issue 5020 - Part 3: Add command line options to compile script

compile

 #!/usr/bin/env python
 
+import argparse
 import os
 import re
 import subprocess
 
 BASE_DIR = os.path.dirname(__file__) or os.getcwd()
-EMSCRIPTEN_PATH = os.path.join(BASE_DIR, '..', 'emscripten')
 SOURCE_DIR = os.path.join(BASE_DIR, 'compiled')
 SOURCE_FILES = [
     os.path.join(path, f)
     for (path, dirs, files) in os.walk(SOURCE_DIR)
     for f in files
     if f.endswith('.cpp')
 ]
 BINDINGS_FILE = os.path.join(SOURCE_DIR, 'bindings.cpp')
 BINDINGS_GENERATOR = os.path.join(SOURCE_DIR, 'bindings.cpp.js')
 BINDINGS_OUTPUT = os.path.join(SOURCE_DIR, 'bindings.js')
@@ skipping 10 matching lines @@
     'NO_FILESYSTEM': 1,
     'INVOKE_RUN': 0,
     'TEXTDECODER': 0,
     'EXPORTED_RUNTIME_METHODS': ['cwrap', 'ccall', 'stringToAscii'],
 }
 DEFINES = []
 ADDITIONAL_PARAMS = ['-O3', '-m32', '-std=gnu++14', '--memory-init-file', '0',
                      '--emit-symbol-map']
 
 
-def getenv():
+def getenv(emscripten_path):
     path = []
     env = {}
     output = subprocess.check_output([
-        '/bin/bash', '-c', os.path.join(EMSCRIPTEN_PATH, 'emsdk_env.sh')
+        '/bin/bash', '-c', os.path.join(emscripten_path, 'emsdk_env.sh')
     ])
     for line in output.splitlines():
         match = re.search(r'^\s*PATH\s*\+=\s*(.*)', line)
         if match:
             path.append(match.group(1))
         match = re.search(r'^\s*(\w+)\s*=\s*(.*)', line)
         if match:
             env[match.group(1)] = match.group(2)
         env['PATH'] = os.pathsep.join([os.environ['PATH']] + path)
     return env
@@ skipping 20 matching lines @@
     ]
     params.extend(SOURCE_FILES)
     params.extend('-D' + flag for flag in DEFINES)
     for key, value in GENERATION_PARAMS.iteritems():
         params.extend(['-s', '%s=%s' % (key, str(value))])
     params.extend(ADDITIONAL_PARAMS)
     subprocess.check_call(params, env=env)
 
 
 if __name__ == '__main__':
-    env = getenv()
+    parser = argparse.ArgumentParser(
+        description='Compile Emscripten-based C++ code to JavaScript'
+    )
+    parser.add_argument(
+        '--emscripten',
+        metavar='DIR',
+        default=os.path.join(BASE_DIR, '..', 'emscripten'),
+        help='Emscripten installation directory'
+    )
+    parser.add_argument(
+        '-d', '--debug',
+        action='store_true',
+        help='Disable code minification'
+    )
+    parser.add_argument(
+        '-t', '--tracing',
+        action='store_true',
+        help='Enable memory tracing'
+    )
+    args = parser.parse_args()
+
+    if args.debug:
+        ADDITIONAL_PARAMS.append('-g1')

[Vasily Kuznetsov, 2017/03/21 18:38:19]

Isn't it a bit misleading that ADDITIONAL_PARAMETERS is named like a constant
but we're modifying it? Maybe it would be better to make a new list and put it
into `env`?
To be honest I have a hard time coming up with realistic scenarios of how
current approach would bite us in the future. However, sometimes reality exceeds
our expectations :)

[Wladimir Palant, 2017/03/22 08:52:12]

I have been wondering the same thing. Yes, let's do it properly.

+    if args.tracing:
+        ADDITIONAL_PARAMS.append('--tracing')
+
+    env = getenv(args.emscripten)
     generate_bindings(env)
     run_compiler(env)