* Prevent csv QUOTE_NONE writer panics without quotechar
Handle csv.writer rows with QUOTE_NONE through a RustPython-owned unquoted writer path so quotechar=None no longer reaches the unfinished csv_core configuration branch. Escape delimiter, newline, quotechar, and escapechar bytes according to the active dialect, and preserve CPython's single-empty-field error behavior.
Constraint: Match CPython csv.writer behavior without changing Lib/ copied stdlib files.
Rejected: Relying on csv_core QuoteStyle::Never | it does not model CPython QUOTE_NONE escaping with quotechar=None.
Confidence: high
Scope-risk: narrow
Directive: Keep QUOTE_NONE writer behavior separate unless csv_core gains matching CPython semantics.
Tested: prek run --all-files; cargo test --workspace --exclude rustpython_wasm --exclude rustpython-venvlauncher; cargo build --release --features sqlite; pytest -v in extra_tests
Assisted-by: Codex:gpt-5.5
* Keep csv parity tests aligned with QUOTE_NONE support
Remove the stale RustPython expected-failure marker for the CPython escaped-field writer test that now passes, and cover CR/LF escaping in the snippet regression requested during review.
Constraint: RustPython test policy allows removing expectedFailure markers only when the upstream test passes.
Rejected: Refactoring writer row boilerplate in this follow-up | review marked it as a heavy-lift nitpick and it would broaden the CI fix.
Confidence: high
Scope-risk: narrow
Tested: cargo run --release --features sqlite -- -m test test_csv; cargo run -- extra_tests/snippets/stdlib_csv.py; PATH=/tmp/pyshim:$PATH prek run --all-files; git diff --check; cargo test --workspace --exclude rustpython_wasm --exclude rustpython-venvlauncher; pytest -v in extra_tests
Assisted-by: Codex:gpt-5.5
* Keep csv quote-style dispatch coherent
Review feedback pointed out that adjacent branches selected behavior from the same quoting discriminator. Use one match so future quote-style additions are routed in a single place.
Constraint: RustPython review requested merging adjacent quote-style checks.
Confidence: high
Scope-risk: narrow
Tested: cargo fmt --check
Tested: target/release/rustpython extra_tests/snippets/stdlib_csv.py
Tested: target/release/rustpython -m test test_csv
Tested: PATH=/tmp/pyshim:$PATH prek run --all-files
Tested: RUST_TEST_THREADS=1 cargo test --workspace --exclude rustpython_wasm --exclude rustpython-venvlauncher -- --test-threads=1
Tested: cargo clippy --workspace --exclude rustpython_wasm --exclude rustpython-venvlauncher --all-targets
Assisted-by: Codex:gpt-5.5
This directory contains all of the Python files that make up the standard
library for RustPython.
Most of these files are copied over from the CPython repository (the 3.7
branch), with slight modifications to allow them to work under RustPython. The
current goal is to complete the standard library with as few modifications as
possible. Current modifications are just temporary workarounds for bugs/missing
feature within the RustPython implementation.
The first big module we are targeting is unittest, so we can leverage the
CPython test suite.
Kwak Byoung Min
2ffde783fc