From 8d4151cfbb76758b1be339cb25187863a0c23465 Mon Sep 17 00:00:00 2001
From: Tim van der Meij <timvandermeij@gmail.com>
Date: Sun, 22 Mar 2026 16:37:59 +0100
Subject: [PATCH] Fix Python caching in the GitHub Actions workflows

For the Python-based workflows we were already using `pip` caching [1],
but sadly this isn't fully functional at the moment because the caching
functionality uses `requirements.txt` to determine when to create or
invalidate the cache. However, we have two different `pip` install
commands but only a `requirements.txt` for one of them (the Fluent
linter), which means that the other job (the font tests) will not
populate the cache with its dependencies.

This can be seen by opening any font tests or Fluent linting build and
noticing that they report the exact same cache key even though their
dependencies are different. In the installation step the dependencies
are reported as "Downloading [package].whl" instead of the expected
"Using cached [package].whl".

This commit fixes the issue by explicitly defining a `requirements.txt`
file for both jobs and pointing the caching functionality to the
specific file paths to make sure that unique caches with the correct
package data are used. While we're here we also align the syntax and
step titles in the files for consistency.

[1] https://github.com/actions/setup-python?tab=readme-ov-file#caching-packages-dependencies
---
 .../{requirements.txt => fluent_linter_requirements.txt} | 0
 .github/font_tests_requirements.txt                      | 1 +
 .github/workflows/fluent_linter.yml                      | 9 ++++-----
 .github/workflows/font_tests.yml                         | 5 +++--
 4 files changed, 8 insertions(+), 7 deletions(-)
 rename .github/{requirements.txt => fluent_linter_requirements.txt} (100%)
 create mode 100644 .github/font_tests_requirements.txt

diff --git a/.github/requirements.txt b/.github/fluent_linter_requirements.txt
similarity index 100%
rename from .github/requirements.txt
rename to .github/fluent_linter_requirements.txt
diff --git a/.github/font_tests_requirements.txt b/.github/font_tests_requirements.txt
new file mode 100644
index 000000000..e8ce6dfc4
--- /dev/null
+++ b/.github/font_tests_requirements.txt
@@ -0,0 +1 @@
+fonttools==4.*
diff --git a/.github/workflows/fluent_linter.yml b/.github/workflows/fluent_linter.yml
index f92d1df03..e7dfbca34 100644
--- a/.github/workflows/fluent_linter.yml
+++ b/.github/workflows/fluent_linter.yml
@@ -34,11 +34,10 @@ jobs:
         with:
           python-version: '3.14'
           cache: 'pip'
+          cache-dependency-path: '.github/fluent_linter_requirements.txt'
 
-      - name: Install Fluent dependencies
-        run: |
-          pip install -r .github/requirements.txt
+      - name: Install requirements
+        run: pip install -r .github/fluent_linter_requirements.txt
 
       - name: Lint Fluent reference files
-        run: |
-          moz-fluent-lint ./l10n/en-US --config .github/fluent_linter_config.yml
+        run: moz-fluent-lint ./l10n/en-US --config .github/fluent_linter_config.yml
diff --git a/.github/workflows/font_tests.yml b/.github/workflows/font_tests.yml
index 6ff7aecde..e8630d330 100644
--- a/.github/workflows/font_tests.yml
+++ b/.github/workflows/font_tests.yml
@@ -56,9 +56,10 @@ jobs:
         with:
           python-version: '3.14'
           cache: 'pip'
+          cache-dependency-path: '.github/font_tests_requirements.txt'
 
-      - name: Install Fonttools
-        run: pip install fonttools
+      - name: Install requirements
+        run: pip install -r .github/font_tests_requirements.txt
 
       - name: Run font tests
         run: npx gulp fonttest --headless