Differential D20877

When generating diffs in "arc diff", disable Git config option "diff.suppressBlankEmpty"
ClosedPublic
Actions

Authored by epriestley on Oct 29 2019, 5:12 PM.

Details

Reviewers: None
Maniphest Tasks: T13432: Diffs that have had trailing whitespace trimmed or were generated with the Git "diff.suppressBlankEmpty" config option render oddly
Commits: rARCdb1959900a64: (stable) Promote 2019 Week 44
rARCcc1ff38843c4: When generating diffs in "arc diff", disable Git config option "diff.

Summary

Ref T13432. Git has a "diff.suppressBlankEmpty" config option which makes it emit nonstandard diffs with trimmed trailing whitespace on unchanged blank lines.

Currently, we don't parse these diffs correctly. Even if we do in the future, emitting a more standard diff is desirable.

Explicitly disable this option when executing "git diff" so we build more standard diffs.

Test Plan

Configured this option.
Modified a file with a blank line in it without changing the blank line, got this goofy display diff:

Applied patch, rediffed the same change, saw "-c diff.suppressBlankEmpty" in "--trace" output and got this sensible diff:

Diff Detail

Repository

rARC Arcanist

Lint

Lint Not Applicable

Unit

Tests Not Applicable

Event Timeline

epriestley created this revision.Oct 29 2019, 5:12 PM

Harbormaster completed remote builds in B23600: Diff 49771.Oct 29 2019, 5:13 PM

This revision was not accepted when it landed; it landed in state Needs Review.Oct 29 2019, 5:13 PM

epriestley requested review of this revision.

Closed by commit rARCcc1ff38843c4: When generating diffs in "arc diff", disable Git config option "diff. (authored by epriestley). · Explain Why

This revision was automatically updated to reflect the committed changes.

epriestley added a commit: rARCcc1ff38843c4: When generating diffs in "arc diff", disable Git config option "diff..

epriestley mentioned this in T13432: Diffs that have had trailing whitespace trimmed or were generated with the Git "diff.suppressBlankEmpty" config option render oddly.Oct 29 2019, 5:15 PM

epriestley added a commit: rARCdb1959900a64: (stable) Promote 2019 Week 44.Nov 4 2019, 2:07 AM

Revision Contents
Changeset List

Path

Size

src/

repository/

api/

ArcanistGitAPI.php

16 lines

Diff 49772

View Options

src/repository/api/ArcanistGitAPI.php

When generating diffs in "arc diff", disable Git config option "diff.suppressBlankEmpty"ClosedPublicActions