[jira] [Created] (GROOVY-12322) Inline the nls parser rule

["Daniel Sun (Jira)" <ji...@apache.org>]

Daniel Sun created GROOVY-12322:
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             Summary: Inline the nls parser rule
                 Key: GROOVY-12322
                 URL: https://issues.apache.org/jira/browse/GROOVY-12322
             Project: Groovy
          Issue Type: Improvement
            Reporter: Daniel Sun


h3. Motivation

{{GroovyParser.g4}} used a shared helper for optional newlines:

{noformat}
nls : NL* ;
sep : (NL | SEMI)+ ;
{noformat}

Because {{sep}} can start with {{NL}}, {{FOLLOW(nls)}} contains {{NL}}. The star inside {{nls}} is therefore not LL(1) at the rule level: generated {{nls()}} always uses adaptivePredict, even at call sites where a simple {{while (LA(1)==NL)}} would be correct. The rule also allocates a {{NlsContext}} for every invocation, including the empty match.

{{classOrInterfaceModifiersOpt}} already inlined {{NL*}} for this reason, with a comment not to put {{nls}} back.

Same class of prediction-cost reduction as GROOVY-12173, applied to newline handling.

h3. Changes

* Delete the {{nls}} rule and write {{NL*}} at every former call site, so each site has its own star decision.
* Teach {{GroovydocManager}} to read {{NL}} terminals as direct children (comments are lexed as {{NL}}). {{sep}} still wraps mixed {{NL}} / {{SEMI}} sequences.

h3. Compatibility

* Language and AST for correct programs are unchanged.
* Parse-tree shape changes: no {{NlsContext}}; empty matches produce no child. {{NlsContext}} is generated parser API, not a stability covenant.
* No public API additions.




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