[CLI-300] Parse -opt=value for multi-character short options

[tanvir-ux]

Fixes https://issues.apache.org/jira/browse/CLI-300

Summary

DefaultParser.handleShortAndLongOption only treated the left-hand side of an equals token as a short option when it was a single character (opt.length() == 1). A multi-character short option such as Option.builder("foo").hasArg() therefore failed on -foo=bar with UnrecognizedOptionException, while -f=bar and -foo bar already worked.

Change

Use Options.hasShortOption(opt) for the equals path, matching the non-equals short-option lookup already used a few lines above. Single-character short options, Java-property style (-Dkey=value), and long options with a single dash (-foo=bar with longOpt("foo")) keep the same behavior.

Tests

• DefaultParserTest#testMultiCharShortOptionWithEqual — regression for the reported case

• DefaultParserTest#testMultiCharShortOptionWithoutEqual — paired non-equals path

• Full mvn build succeeds locally

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[garydgregory]

A short option is, IIRC, by definition of length one, and allows for grouping -a -b -c into -abc.

[tanvir-ux]

Thanks. POSIX short options are one character, agreed. Commons CLI currently still documents multi-character opt in OptionValidator and already parses -foo bar via hasShortOption; CLI-300 is only the missing -foo=bar path. Happy to close this if you'd rather keep the equals path limited to length-1 short options.

[garydgregory]

I'll have to review the issue again later.