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…ions (#71) Replace the LOOKAHEAD( VariableDeclarationExpression() ";" ) used to disambiguate local variable declarations from other statements with a purely syntactic lookahead: LOOKAHEAD( Modifiers() Type() Identifier() ( ArrayBracketPair() )* ( "," | "=" | ";" ) ) Performing a full parse of the declarator inside the lookahead swallows the parse error of malformed input such as `int i = ;`: error recovery then reports the start of the statement instead of the offending token. The syntactic lookahead keeps the same disambiguation while letting the actual VariableDeclarationExpression() parse report the precise error. This restores the error positions required by KeY (see KeYProject/key commit b7b5bb1), which can now be reverted together with the corresponding error-message test modifications. Adds a regression test asserting the error is reported at the offending '=' token and not at the statement start.
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Fixes #71
Summary
Replaces the statement-level lookahead in
javaparser-core/src/main/javacc/java.jj:with a purely syntactic lookahead:
Performing a full parse of the declarator inside the lookahead swallows
the parse error for malformed input such as
int i = ;: error recoveryreports the start of the statement instead of the offending token. The
syntactic lookahead keeps the same disambiguation between local variable
declarations and other (incl. JML) statements, while letting the actual
VariableDeclarationExpression()parse report the exact error position.Motivation
This restores the precise error positions documented in the issue, so
KeYProject/key#b7b5bb1
(and the accompanying error-message test changes) can be reverted.
Verification
Before:
int i = ;reported(line 1,col 20) Parse error. Found "int"(statement start)After:
(line 1,col 28) Parse error. Found ";"(the offending=/;)Parser regenerated with javacc, 0 errors.
Added regression test
VariableDeclarationErrorPositionTest.Full
:jmlparser-core-testing:test,:jmlparser-jml-tests:test,:javaparser-key-testing:testand:jmlparser-symbol-solver-testing:testpass.