Fix NullPointerException in UselessTernaryOperatorDiagnostic for malformed ternary operators #3728

Copilot · 2026-01-02T17:40:58Z

Fix NullPointerException in UselessTernaryOperatorDiagnostic

The issue occurs when parsing malformed ternary operators like Возврат ?(таблица.Количество() = 1, Неопределено, ); where the third expression is missing or malformed.

Plan:

Changes Made:

Modified UselessTernaryOperatorDiagnostic.java: Use ctx.getChildCount() == 1 instead of manual null check in the getBooleanToken method (line 120)
Added test file: Created UselessTernaryOperatorDiagnosticMalformed.bsl with malformed ternary operator example
Improved test: Rewrote testMalformedTernaryOperatorDoesNotThrowNPE() to use assertThatCode(() -> getDiagnostics(documentContext)).doesNotThrowAnyException() pattern to specifically test that getting diagnostics doesn't throw

Root Cause:

The parser can create an ExpressionContext with null children when parsing malformed code. The original code tried to call ctx.children.size() without checking if children was null first, causing a NullPointerException.

Fix:

Use the safe getChildCount() method which handles null children internally: ctx.getChildCount() == 1

Original prompt

This section details on the original issue you should resolve

<issue_title>NullPointerException: Cannot invoke "java.util.List.size()" because "ctx.children" is null</issue_title>
<issue_description>Sentry Issue: BSL-LANGUAGE-SERVER-PY

NullPointerException: Cannot invoke "java.util.List.size()" because "ctx.children" is null
    at com.github._1c_syntax.bsl.languageserver.diagnostics.UselessTernaryOperatorDiagnostic.lambda$getBooleanToken$1(UselessTernaryOperatorDiagnostic.java:120)
    at com.github._1c_syntax.bsl.languageserver.diagnostics.UselessTernaryOperatorDiagnostic.getBooleanToken(UselessTernaryOperatorDiagnostic.java:120)
    at com.github._1c_syntax.bsl.languageserver.diagnostics.UselessTernaryOperatorDiagnostic.visitTernaryOperator(UselessTernaryOperatorDiagnostic.java:67)
    at com.github._1c_syntax.bsl.languageserver.diagnostics.UselessTernaryOperatorDiagnostic.visitTernaryOperator(UselessTernaryOperatorDiagnostic.java:42)
    at com.github._1c_syntax.bsl.parser.BSLParser$TernaryOperatorContext.accept(BSLParser.java:5332)
...
(55 additional frame(s) were not displayed)
```</issue_description>

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

<comments>
<comment_new><author>@nixel2007</author><body>
```bsl
Return ( table.Count () = 1, undefined, );

@copilot код, на котором падает.</comment_new>

Fixes NullPointerException: Cannot invoke "java.util.List.size()" because "ctx.children" is null #3727

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coderabbitai · 2026-01-02T17:41:03Z

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Add null check for ctx.children before accessing its size to prevent NPE when parsing malformed ternary operators Co-authored-by: nixel2007 <[email protected]>

...a/com/github/_1c_syntax/bsl/languageserver/diagnostics/UselessTernaryOperatorDiagnostic.java

...m/github/_1c_syntax/bsl/languageserver/diagnostics/UselessTernaryOperatorDiagnosticTest.java

- Replace ctx.children null check with ctx.getChildCount() method - Rewrite test to properly get diagnostics list and assert with assertj Co-authored-by: nixel2007 <[email protected]>

...m/github/_1c_syntax/bsl/languageserver/diagnostics/UselessTernaryOperatorDiagnosticTest.java

- Import assertThatCode from assertj - Replace isEmpty() assertion with doesNotThrowAnyException() - Specifically test that getDiagnostics call doesn't throw NPE Co-authored-by: nixel2007 <[email protected]>

nixel2007 · 2026-01-02T19:10:05Z

/buildJar

github-actions · 2026-01-02T19:11:37Z

✅ Собраны JAR-файлы для этого PR по команде /buildJar.

Артефакт: 5010181738

Файлы внутри:

bsl-language-server-copilot-fix-nullpointerexception-issue-267ce98-exec.jar

Copilot

Pull request overview

This PR fixes a NullPointerException that occurs in the UselessTernaryOperatorDiagnostic when parsing malformed ternary operators where the third expression is missing or malformed (e.g., Возврат ?(таблица.Количество() = 1, Неопределено, );).

Key changes:

Replaced unsafe direct access to ctx.children.size() with the safe ctx.getChildCount() method
Added a test case to verify the fix handles malformed ternary operators without throwing exceptions

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated no comments.

File	Description
`src/main/java/com/github/_1c_syntax/bsl/languageserver/diagnostics/UselessTernaryOperatorDiagnostic.java`	Changed line 120 to use `getChildCount()` instead of direct `children.size()` access to safely handle null children
`src/test/java/com/github/_1c_syntax/bsl/languageserver/diagnostics/UselessTernaryOperatorDiagnosticTest.java`	Added test method to verify malformed ternary operators don't cause NullPointerException
`src/test/resources/diagnostics/UselessTernaryOperatorDiagnosticMalformed.bsl`	Added test resource file with malformed ternary operator example

The code changes are well-implemented and follow the project's conventions. The fix correctly addresses the root cause by using ANTLR's built-in getChildCount() method which safely handles null children. The test follows the established pattern in the codebase for testing exception-free behavior using assertThatCode().doesNotThrowAnyException().

Initial plan

c475dbf

Copilot AI assigned Copilot and nixel2007 Jan 2, 2026

Copilot started work on behalf of nixel2007 January 2, 2026 17:41 View session

Fix NullPointerException in UselessTernaryOperatorDiagnostic

6dc20aa

Add null check for ctx.children before accessing its size to prevent NPE when parsing malformed ternary operators Co-authored-by: nixel2007 <[email protected]>

nixel2007 reviewed Jan 2, 2026

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nixel2007 reviewed Jan 2, 2026

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Copilot AI changed the title ~~[WIP] Fix NullPointerException in UselessTernaryOperatorDiagnostic~~ Fix NullPointerException in UselessTernaryOperatorDiagnostic for malformed ternary operators Jan 2, 2026

Copilot AI requested a review from nixel2007 January 2, 2026 17:58

Copilot finished work on behalf of nixel2007 January 2, 2026 17:58

Copilot started work on behalf of nixel2007 January 2, 2026 18:01 View session

Use getChildCount() and improve test with assertj

9f3ab19

- Replace ctx.children null check with ctx.getChildCount() method - Rewrite test to properly get diagnostics list and assert with assertj Co-authored-by: nixel2007 <[email protected]>

Copilot finished work on behalf of nixel2007 January 2, 2026 18:10

nixel2007 reviewed Jan 2, 2026

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...m/github/_1c_syntax/bsl/languageserver/diagnostics/UselessTernaryOperatorDiagnosticTest.java Show resolved Hide resolved

Copilot started work on behalf of nixel2007 January 2, 2026 19:04 View session

Use assertThatCode with lambda to test getDiagnostics doesn't throw

267ce98

- Import assertThatCode from assertj - Replace isEmpty() assertion with doesNotThrowAnyException() - Specifically test that getDiagnostics call doesn't throw NPE Co-authored-by: nixel2007 <[email protected]>

nixel2007 marked this pull request as ready for review January 2, 2026 19:09

Copilot AI review requested due to automatic review settings January 2, 2026 19:09

Copilot started reviewing on behalf of nixel2007 January 2, 2026 19:10 View session

nixel2007 enabled auto-merge January 2, 2026 19:10

Copilot finished work on behalf of nixel2007 January 2, 2026 19:14

Copilot AI requested a review from nixel2007 January 2, 2026 19:14

Copilot AI reviewed Jan 2, 2026

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nixel2007 merged commit 9c1f478 into develop Jan 2, 2026
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nixel2007 deleted the copilot/fix-nullpointerexception-issue branch January 2, 2026 19:25

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Fix NullPointerException in UselessTernaryOperatorDiagnostic for malformed ternary operators #3728

Fix NullPointerException in UselessTernaryOperatorDiagnostic for malformed ternary operators #3728

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Fix NullPointerException in UselessTernaryOperatorDiagnostic for malformed ternary operators #3728

Fix NullPointerException in UselessTernaryOperatorDiagnostic for malformed ternary operators #3728

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