Running Forge 1.12-14.21.1.2397, 64bit java 8 update 131
ForgeGradle and Minecraft are using jopt-simple-5.0.3, but Forge still seems to be using jopt-simple:4.6. This might be causing strange exceptions when calling any method deriving from JOpt.
For example:
parser.acceptsAll(Arrays.asList("help", "?"), "Help");
will throw
java.lang.NoSuchMethodError: joptsimple.OptionParser.acceptsAll(Ljava/util/List;)Ljoptsimple/OptionSpecBuilder;
ONLY when running outside the developer environment, otherwise it runs just fine.
Edit: just to be clear. I am talking about the dependencies listed in the json file inside the versions folder.