Support fmt: skip on compound statements

[MichaReiser]

Summary

This PR adds support for trailing fmt: skip comments suppressing the formatting of a compound statement's clause header (if, elif, try...)

Test Plan

I added new test cases

[MichaReiser]

Current dependencies on/for this PR:

• main
  • PR Use single lookup for leading, dangling, and trailing comments #6589
    • PR Support fmt: skip for simple-statements and decorators #6561
      • PR Support fmt: skip on compound statements #6593 👈

This comment was auto-generated by Graphite.

[MichaReiser]

The pattern is always the same. Test if there's a trailing skip comment and, if so, call SuppressedClauseHeader. The enclosing node remains responsible for formatting the body and the trailing comments.

We could wrap this in a ClauseHeader struct but it would result in the same level of nesting because it would need to accept a Format object to write the content. It may be worth adding considering that @tjkuson needs it in #6592 to collapse ... bodies.

[github-actions]

PR Check Results

Benchmark

Linux

group                                      main                                    pr
-----                                      ----                                    --
formatter/large/dataset.py                 1.03      3.9±0.28ms    10.5 MB/sec     1.00      3.8±0.35ms    10.8 MB/sec
formatter/numpy/ctypeslib.py               1.01   776.0±37.22µs    21.5 MB/sec     1.00   769.0±70.03µs    21.7 MB/sec
formatter/numpy/globals.py                 1.00     77.8±7.67µs    37.9 MB/sec     1.06     82.2±5.34µs    35.9 MB/sec
formatter/pydantic/types.py                1.01  1481.6±220.30µs    17.2 MB/sec    1.00  1469.3±93.90µs    17.4 MB/sec
linter/all-rules/large/dataset.py          1.00     11.9±0.44ms     3.4 MB/sec     1.06     12.6±0.71ms     3.2 MB/sec
linter/all-rules/numpy/ctypeslib.py        1.00      3.2±0.10ms     5.3 MB/sec     1.03      3.2±0.12ms     5.1 MB/sec
linter/all-rules/numpy/globals.py          1.00   454.6±18.04µs     6.5 MB/sec     1.06   482.9±41.58µs     6.1 MB/sec
linter/all-rules/pydantic/types.py         1.00      6.2±0.22ms     4.1 MB/sec     1.06      6.6±0.33ms     3.8 MB/sec
linter/default-rules/large/dataset.py      1.00      6.5±0.32ms     6.2 MB/sec     1.01      6.6±0.31ms     6.2 MB/sec
linter/default-rules/numpy/ctypeslib.py    1.00  1344.7±55.15µs    12.4 MB/sec     1.06  1424.2±76.70µs    11.7 MB/sec
linter/default-rules/numpy/globals.py      1.00    183.9±7.88µs    16.0 MB/sec     1.01   184.8±10.45µs    16.0 MB/sec
linter/default-rules/pydantic/types.py     1.00      2.9±0.14ms     8.7 MB/sec     1.01      3.0±0.15ms     8.6 MB/sec

Windows

group                                      main                                   pr
-----                                      ----                                   --
formatter/large/dataset.py                 1.00      3.7±0.02ms    11.0 MB/sec    1.01      3.7±0.03ms    10.9 MB/sec
formatter/numpy/ctypeslib.py               1.00    739.7±7.58µs    22.5 MB/sec    1.01    747.6±9.00µs    22.3 MB/sec
formatter/numpy/globals.py                 1.00     77.2±1.14µs    38.2 MB/sec    1.01     78.2±2.17µs    37.7 MB/sec
formatter/pydantic/types.py                1.00  1514.5±14.79µs    16.8 MB/sec    1.02  1539.5±81.10µs    16.6 MB/sec
linter/all-rules/large/dataset.py          1.01     13.1±0.06ms     3.1 MB/sec    1.00     12.9±0.10ms     3.1 MB/sec
linter/all-rules/numpy/ctypeslib.py        1.00      3.6±0.04ms     4.6 MB/sec    1.00      3.6±0.02ms     4.6 MB/sec
linter/all-rules/numpy/globals.py          1.00    380.0±6.09µs     7.8 MB/sec    1.00    378.8±5.13µs     7.8 MB/sec
linter/all-rules/pydantic/types.py         1.00      6.8±0.06ms     3.7 MB/sec    1.00      6.8±0.11ms     3.7 MB/sec
linter/default-rules/large/dataset.py      1.02      7.2±0.05ms     5.6 MB/sec    1.00      7.1±0.04ms     5.7 MB/sec
linter/default-rules/numpy/ctypeslib.py    1.00  1488.4±10.67µs    11.2 MB/sec    1.00   1488.6±9.56µs    11.2 MB/sec
linter/default-rules/numpy/globals.py      1.00    154.4±1.57µs    19.1 MB/sec    1.00    154.8±3.34µs    19.1 MB/sec
linter/default-rules/pydantic/types.py     1.00      3.2±0.02ms     8.0 MB/sec    1.00      3.2±0.02ms     8.0 MB/sec

[MichaReiser]

@charliermarsh The PR has two commits:

1. Repeats the code to check whether there's a suppression comment. Plain and simple but with some repetitive code.
2. Introduces a new clause_header formatter that checks the suppression and formatting the :, the trailing colon comment, and any potential leading comments.

I'm undecided whether 2 is over-engineer. Wdyt?

[MichaReiser]

The formatting of the case header has been moved into the format_with. The clause_header implementation now takes care of writing the : and the trailing colon comments.

[MichaReiser]

The ClauseHeader abstractin could potentially also be useful in placement.rs

[charliermarsh]

Haha yeah, this is a close one, but I like what you have in the second commit, it doesn't feel over-engineered to me and is more declarative + feels very consistent with the other design patterns in the formatter.