coffee-deps-check

#! /usr/bin/python
#------------------------------------------------------------------------------#
# coffee-deps-check
# by Remi Attab on 30-10-2012
#
# Checks the require statements in coffee scripts to see if they are also
# present  in its build dependency.
#
# If not arguments are provided then this script acts like a git pre-commit hook
# and will fetch the list of files to check from git (git diff
# --cached).
#
# To run the script as batch process, just provide a list of coffee scripts as
# arguments. The script will then check of the coffee scripts in turn.
#
#------------------------------------------------------------------------------#


import sys
import re
import subprocess
import jmlbuild
import os

def git_files():
    """
    Returns all the .coffee file that are about to be committed.
    """
    process = subprocess.Popen(
        ["git", "diff", "--cached", "--name-only"],
        stdout = subprocess.PIPE,
        stderr = subprocess.PIPE)

    while True:
        ret = process.poll()
        line = process.stdout.readline()
        yield line
        if ret is not None: return


def parse_script(path):
    """
    finds all the require statement in a coffeescript file and returns a list of
    the required modules.
    """
    modules = []

    with open(path, 'r') as f:
        for line in f:
            m = re.match(r".*\brequire\W*\(?\W*[\"'](\w+)[\"']\)?\W*$", line)
            if not m: continue
            if re.match(r".*#.*require.*", line): continue

            modules.append(m.group(1))

    return modules

def check_deps(path, graph, module, requires):
    """
    Checks the given set of requires against a edges defined in the dependency
    graph.
    """
    if module + jmlbuild.Ext.NODEJS_MODULE in graph.edges:
        module = module + jmlbuild.Ext.NODEJS_MODULE

    elif module + jmlbuild.Ext.NODEJS_TEST in graph.edges:
        module = module + jmlbuild.Ext.NODEJS_TEST

    if False:
        print "MODULE: ", module
        print "REQUIRES: ", requires
        print "EDGES: ", graph.edges[module]

    if not module in graph.edges:
        print "%s: no target defined for %s" % (path, module)
        return 1

    deps = []
    for d in requires:
        if d + jmlbuild.Ext.NODEJS_MODULE in graph.edges:
            deps.append(d + jmlbuild.Ext.NODEJS_MODULE)

        elif d + jmlbuild.Ext.NODEJS_ADDON in graph.edges:
            deps.append(d + jmlbuild.Ext.NODEJS_ADDON)


    error = 0
    for d in deps:
        if not d in graph.edges[module]:
            print "%s: %s missing dependency on %s" % (path, module, d)
            error = 1

    for d in graph.edges[module]:
        if not d in deps:
            print "%s: %s extra dependency on %s" % (path, module, d)

    return error


def check_script(path):
    """
    Runs the script for a given filename.
    """
    if not path.endswith(".coffee"): return
    if not os.path.exists(path): return

    requires = parse_script(path)

    script = os.path.split(path)[1]
    module = script.split(".")[0]

    return check_deps(path, graph, module, requires)


build_folder = jmlbuild.find_dotgit(os.getcwd())
graph = jmlbuild.parse_makefile("Makefile", build_folder)
error = 0

if len(sys.argv) > 1:
    for path in sys.argv[1:]:
        error = check_script(path) or error

else:
    for line in git_files():
        line = line[:len(line) -1]
        error = check_script(line) or error

if error != 0:
    print "ERROR: Add the missing coffee script dependencies and try again."
else:
    print "No missing coffee script dependencies detected."

sys.exit(error)