Add `version` command line option

[Marcono1234]

Problem solved by this feature

Commit 40cfc84 changed it so the version information does not include the commit hash anymore if the version indicates that the build is a release. This can make handling GitHub bug reports more difficult if people checked out the release and then modified the source:

• If they do not commit their changes, the version information will not indicate that their working tree is dirty
• If they do commit their changes, but do not change the CFR version (so it remains on the release version), the version information will not indicate this

I was thinking about adding a version command line option which always includes the commit hash. And then adjust the bug_report.md GitHub issue template to say that this option should be used to get the version information.

The problem is that this version option is not really an option, the same way --help is not an option either. I would rather consider them "commands" because they also work without argument (for version it only works without argument) and combining them with other options makes no sense, though the similar syntax suggests it would:

java -jar cfr.jar --labelledblocks true --help test --override false my.jar

Feature description

Do not implement help and version as regular options, but as commands. To prevent ambiguities a decompile command should be added which acts the same way the current command line parsing does. help without arguments should list all commands (and for decompile all options). And help with argument should only use the argument to look up decompile options, but not commands.

Examples:

• java -jar cfr.jar help
• java -jar cfr.jar help labelledblocks
• java -jar cfr.jar version
• java -jar cfr.jar decompile --override false my.jar

Considerations

• It breaks command line backward compatibility since now you have to prefix the command with decompile
• You would have to type an additional word decompile when decompiling
• The connection between the help and decompile command might not be obvious enough

Alternatives

Introduce special casing and hacky workarounds?

[Lanchon]

sorry but big thumbs down to this change. never break unnecessarily. everybody will hate CFR for it. and '--version' is the standard tried and true way of doing this.

i'm all for the added version info though, just not the API change.

[leibnitz27]

Hey -

so - I really don't like the addition of decompile. (no surprises there ;) ) - as such I really don't want to go down that route - would significantly prefer to stick with arguments, even if semantically it's a little fluffy,

I'm not ENORMOUSLY averse to reverting https://github.com/leibnitz27/cfr/commit/40cfc84940c6c64105071faa50490b6c8b9f35c8 for the next release.

I would consider repurposing the existing showversion parameter - it's currently a boolean, but there's no reason it couldn't have a larger range, with backwards compatibility

false (existing) / minimal = (just show the name, because sheesh a LITTLE CREDIT PLEASE). true (existing) / normal = (name + hash in snapshot) full (new) = ALL MANNER OF STUFF.