commit 6f6d64d4233bb3d9c7c47d153a4c930c15a75d0c
author Jonathan Lee <jonathanjlee@google.com> Fri Oct 06 20:56:18 2023
committer Chromium LUCI CQ <chromium-scoped@luci-project-accounts.iam.gserviceaccount.com> Fri Oct 06 20:56:18 2023
tree a79863b72e2822077bf7fdc3d3b827f97f387555
parent 52be9fc9ba84f822fb1d7d29ebcb4e5f78de26bb

[web-tests] Fix incorrect fuzziness parameter minimums

A W(P)T may specify fuzziness parameters as either an inclusive range
[min, max], or a single expected value [1] (e.g., `totalPixels=30` means
exactly 30 pixels must be different for a test/reference to match).

This patch corrects a few tests that mistakenly reject exact matches
(i.e., maxDifference = totalPixels = 0) because they specify exact
nonzero parameters. WPT unfortunately doesn't interpret this as `0-<N>`,
even though this is almost always what we want in practice.

`run_web_tests.py` allowed these parameters to land because it ignores
fuzzy parameters when the image hashes match exactly. Now, to be
consistent with [1] and its implementation in wptrunner, only skip
diffing when exact matches are expected.

[1]: https://web-platform-tests.org/writing-tests/reftests.html#fuzzy-matching

Bug: 1254776
Change-Id: I868e571a891b2a570934d17dd605f42db22a0ddf
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4908234
Reviewed-by: Weizhong Xia <weizhong@google.com>
Commit-Queue: Jonathan Lee <jonathanjlee@google.com>
Cr-Commit-Position: refs/heads/main@{#1206623}