generate_mod_launch_args.py

import zipfile
import sys
import java_manifest

if len(sys.argv) != 2:
    sys.exit('''Usage: {} JAR_PATH

Generates JVM and program arguments needed to launch a mod in an IDE directly, given a jar of it.'''.format(sys.argv[0]))

man = java_manifest.loads(zipfile.ZipFile(sys.argv[1]).open("META-INF/MANIFEST.MF", "r").read().decode("utf8"))[0]

jvmArgs = []
programArgs = []

if "TweakClass" in man:
    programArgs += ["--tweakClass " + man["TweakClass"]]

if "MixinConfigs" in man:
    programArgs += ["--mixin " + x for x in man["MixinConfigs"].split(",")]

if "FMLCorePlugin" in man:
    jvmArgs += ["-Dfml.coreMods.load=" + man["FMLCorePlugin"]]

print("JVM arguments:")
print(" ".join(jvmArgs))
print()
print("Program arguments:")
print(" ".join(programArgs))