[ycherkes]

The collection-expression rewriter passed nullable visitor results into required expression operands, producing CS8600, CS8631, and CS8604 warnings in both Roslyn builds. Fall back to the original operand when a visit returns null for null-coalescing operands and collection assignment targets, matching the existing null-conditional rewriter pattern.

Validation:

• Clean Release solution rebuild passed with no warnings in source/SyntaxRewriters/ (16 warnings eliminated across both Roslyn builds). The remaining 43 warnings are in generated integration-test sources.
• All 224 solution tests passed, with no failures or skips.
• git diff --check passed.

[chatgpt-codex-connector]

Codex Review Summary: ✅ Completed

This comment shows the latest Codex review activity on this pull request.

Review	Status	Commit	Review trigger
📝 Code Review	✅ Completed 2026-11-06T20:14:27.998795Z	696144c	PR opened

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