Recognize ignores after multiline strings inside f-strings - #4953
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According to mypy_primer, this change doesn't affect type check results on a corpus of open source code. ✅ |
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Summary: **Context** Pyrefly must decide whether a hash character starts a comment or is part of a Python string. The old ignore scanner tracked quotes without parsing f-string replacement fields. It could treat a hash inside a nested string as an ignore directive. It could also treat a triple-quoted string in a replacement field as an open string and then miss a real ignore directive on a later line. **Goal** Use the Python parser result to identify comments. Ignore handling must follow the same syntax as the parsed module. This fixes GitHub issue 4118. **Changes** - Read ignore directives only from Comment tokens recorded by the parser. - Remove the old quote scanner and its multiline-string state. - Use the same physical-line rules for line-level and file-level directives. - Test multiline strings in f-strings, raw f-strings, and t-strings. - Test same-quote nesting, CRLF, and bare CR. - Test hash characters inside replacement fields. - Test suppression insertion after an f-string expression. **Behavior** A hash inside an f-string replacement field is no longer treated as a comment. A real ignore directive after a replacement field or a multiline string is now recognized. File-level directives also keep the correct line number when the source contains a bare carriage return. **Source** - GitHub issue: #4118 - GitHub pull request: #4953 - GitHub author: Ching-Wei Kang <164879897+WilliamK112@users.noreply.github.com> Reviewed By: rchen152 Differential Revision: D120384969 fbshipit-source-id: 48c246f82ec96fa4ee8b060ecdc501ffa438f88c
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Fixes #4118.
The lightweight suppression scanner treats a triple-quoted string inside an f-string expression as a new, still-open multiline string. That hides real ignore comments on later lines. When a file may contain both an f-string and a multiline string, this change uses the existing Ruff lexer to locate actual comment tokens; other files retain the lightweight scanner. Regression coverage checks the original example, an embedded fake ignore, CRLF input, and an end-to-end suppressed assignment.
Validation:
cargo test -p pyrefly_python --lib: 79 passed.cargo test -p pyrefly test::suppression --lib: 44 passed.python3 test.py --no-test --no-tensor-shapes --no-conformance --no-jsonschema: passed.cargo test -p pyrefly --lib: 8565 passed, 3 failed locally in unrelated LSP fixture tests. Two concernwhatthepatchimport diagnostics; the third istest_workspace_discovers_project_venv, where the test used/opt/anaconda3instead of its fixture.venv. These fixture files do not enter the changed f-string lexer path. Hosted CI will provide an independent result.