Features / improvements

• New grammar option: contextSuperClass. All parse tree internal nodes will derive from this. Default is ParserRuleContext. Should derive from ultimately RuleContext at minimum.
  Java target can use contextSuperClass=org.antlr.v4.runtime.RuleContextWithAltNum for convenience. It adds a backing field for altNumber, the alt matched for the associated rule node.
• Added getMaxTokenType() to Vocabulary interface

Complete list of pull requests for 4.5.3 but most of those are fixing bugs.

Issues

Complete list of issues closed/solved for 4.5.2.