test(es/minifier): Add execution tests for issue #11517

[kdy1]

Summary

• Add 113 execution tests to verify the fix for issue SWC minifier incorrectly merges conditions (semantic change) #11517 (incorrect if statement merging when local variables have different values)

This PR adds comprehensive test coverage for PR #11526.

Test Coverage

Core Issue Tests:

• Original reproduction case from issue
• Simplified version
• Verification that correct merging still works

Variable Type Variations:

• const, let, var declarations
• Multiple local variables with same names

Statement Type Variations:

• return, continue, break, throw statements
• Try-catch blocks, labeled statements

Data Structure Variations:

• Objects, Arrays, Maps, Sets, WeakMap, WeakSet
• TypedArrays, DataView, Proxies, Reflect API

Function Variations:

• Regular functions, arrow functions
• Async functions, generators
• Class methods, constructors, closures, IIFEs

Control Flow Variations:

• Nested if statements, if-else-if chains
• For/while/do-while/for-of/for-in loops
• Switch statements

Real-World Patterns:

• HTTP status codes, form validation
• Redux-like reducers, i18n translations
• Theme systems, logging, API responses
• File handlers, command parsers, permissions

Test plan

• All 113 new tests pass
• All existing execution tests still pass

🤖 Generated with Claude Code

[changeset-bot]

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Latest commit: 6b543dc

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[Copilot]

Pull request overview

This PR extends the minifier’s execution test suite to comprehensively cover the fix for issue #11517 (incorrect merging of if statements when their local variables differ), ensuring both the original regression and a wide matrix of variants are protected. The changes are entirely in test code and exercise many language and control-flow patterns to validate that if-merging only occurs when it is semantics-preserving.

Changes:

• Add an execution test for the original reproduction of #11517 and a simplified core variant.
• Add a large family of execution tests spanning variable kinds, control-flow constructs, data structures, and modern JS features, all structured to catch incorrect if-merging when local variable values differ.
• Include a positive test that verifies that merging still works when branch-local values are intentionally identical.

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[github-actions]

Binary Sizes

File	Size
swc.linux-x64-gnu.node	28M (28689992 bytes)

Commit: 8849810

[codspeed-hq]

CodSpeed Performance Report

Merging this PR will not alter performance

_{Comparing issue-11517-tests (6b543dc) with main (ff6cf88)}

Summary

✅ 184 untouched benchmarks

[kdy1]

@claude Remove unnecessary tests. e.g. Duplicate (verified by other test case)

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✅ kdy1
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[claude]

PR Review: test(es/minifier): Add execution tests for issue #11517

Overview

This PR adds execution tests to verify the fix for issue #11517, which involves incorrect if-statement merging when local variables have different values. The tests are well-structured and cover a good variety of scenarios.

👍 Strengths

1. Good test coverage: The tests cover multiple important variations:

   • Original reproduction case from the issue
   • Different variable declaration types (const, let, var)
   • Different control flow statements (return, continue, break, throw)
   • Class methods and closures
   • Real-world patterns (HTTP status codes)

2. Clear documentation: Each test has a descriptive doc comment explaining what it tests, which is actually an improvement over some existing tests in the file.

3. Consistent style: Uses run_default_exec_test() appropriately for most tests, which is the standard pattern for execution tests with default minifier config.

4. Edge case consideration: Including issue_11517_same_values_should_merge is a great decision - it ensures the fix doesn't break valid merging behavior.

⚠️ Issues to Address

1. PR description inaccuracy: The PR description claims "113 execution tests" but only 11 tests are actually added. This should be corrected to avoid confusion.

2. PR fix(es/minifier): Inline before merge if #11526 is still open: This test PR references PR fix(es/minifier): Inline before merge if #11526 as the fix, but fix(es/minifier): Inline before merge if #11526 hasn't been merged yet. Consider:

   • Either merging fix(es/minifier): Inline before merge if #11526 first and then this test PR
   • Or combining these tests with the fix PR itself to ensure tests and fix are landed together

💡 Suggestions (Optional)

1. Minor typo in doc comment: In issue_11517_original, the comment says "Original reproduction case" but the test differs slightly from the original issue (uses 'A error occurred' vs 'A error occured' in the issue). This is fine since it tests the same pattern, but consistency could help.

2. Consider edge cases: A few additional edge cases that could strengthen coverage (optional for future):

   • Nested if statements with different local variable values at different nesting levels
   • Switch statements with similar patterns

✅ Verdict

The code quality is good and follows repository conventions. The tests are valuable regression tests for issue #11517.

Recommendation: Fix the PR description (113 → 11 tests) and coordinate with PR #11526 for merging order.

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Reviewed by Claude Code