Use case

Chromium maintainers often add .patch files that keep track of Chromium-specific fix-forwards to the Chromium fork of the ICU library. https://chromium.googlesource.com/chromium/deps/icu

Each such addition breaks the license checker because a new file has appeared. This generates churn to fix the roller, but adds no value to the license checking process.

Today we have a particularly onerous situation, with as many as 6 such changes in the pipeline, see : https://chromium.googlesource.com/chromium/deps/icu/+/9408c6fd4a39e6fef0e1c4077602e1c83b15f3fb

Proposal

To avoid further churn, I proposed that we ignore the .patch directory in the license checker.

Flutter maintainers support this change.

Note that the .patch files are never used during build, and their contents have already been applied to the ICU code base at the point where flutter attempts to use it. If they amend existing files, this will not affect the license checker anyways, and if they happen to add new files, the license checker will be tripped anyways.