Fix ANTLR4 JS binding to throw on syntax errors instead of returning partial trees

[Copilot]

ANTLR4's JavaScript parser was silently logging syntax errors while returning partial parse trees, allowing invalid input to proceed.

Changes

• Added ThrowingErrorListener: Custom error listener that throws Error on syntax errors instead of logging
• Updated parse() and unparse(): Removed default error listeners, installed throwing listener on both lexer and parser
• Added error handling tests: 5 test cases covering malformed syntax scenarios

Before/After

// Before: logs error, returns partial tree
parse("(a + b -> c");
// line 1:7 no viable alternative at input '(a+b->'
// => "----\n"

// After: throws immediately
parse("(a + b -> c");
// Error: line 1:7 no viable alternative at input '(a+b->'

All existing tests pass. Error messages include line/column information from ANTLR4.

Warning

Firewall rules blocked me from connecting to one or more addresses (expand for details)

I tried to connect to the following addresses, but was blocked by firewall rules:

• central.sonatype.com
  • Triggering command: /home/REDACTED/.local/bin/antlr4 antlr4 -Dlanguage=JavaScript Dsp.g4 -visitor -no-listener -o atsds_bnf (dns block)
  • Triggering command: /home/REDACTED/.local/bin/antlr4 antlr4 -Dlanguage=JavaScript Ds.g4 -visitor -no-listener -o atsds_bnf (dns block)

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Original prompt

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This section details on the original issue you should resolve

<issue_title>antlr4的js binding中，如果语法出错，他也会给出能parse的部分，需要让他throw error</issue_title>
<issue_description>在 bnf 目录下面</issue_description>

Comments on the Issue (you are @copilot in this section)

• Fixes antlr4的js binding中，如果语法出错，他也会给出能parse的部分，需要让他throw error #107

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[Copilot]

Pull request overview

This PR fixes ANTLR4's JavaScript parser binding to throw errors on syntax errors instead of silently logging them and returning partial parse trees. This ensures invalid input is immediately rejected rather than being partially processed.

Key Changes:

• Implemented custom ThrowingErrorListener class that throws errors instead of logging them
• Updated parse() and unparse() functions to remove default error listeners and install the throwing listener on both lexer and parser
• Added 5 comprehensive error handling tests covering various malformed syntax scenarios

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.

File	Description
bnf/atsds_bnf/index.mjs	Adds ThrowingErrorListener class and integrates it into both parse() and unparse() functions by removing default listeners and adding the throwing listener to lexer and parser
bnf/tests/test_parse_unparse.mjs	Adds 5 error handling test cases for missing parentheses, bad syntax, malformed expressions, incomplete binary, and malformed function syntax

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[Copilot]

The error listener setup code is duplicated in both parse() and unparse() functions. Consider extracting this into a helper function to reduce code duplication and improve maintainability. For example, you could create a function like setupThrowingErrorListener(lexer, parser) that removes default listeners and adds the throwing listener to both the lexer and parser.