Bug 1555560: Run black format check in automation; r=ahal,sylvestre

Differential Revision: https://phabricator.services.mozilla.com/D33126

build/sparse-profiles/docker-image

@@ -16,6 +16,7 @@ path:tools/lint/eslint/eslint-plugin-mozilla/manifest.tt
 path:tools/lint/eslint/manifest.tt
 path:tools/lint/python/flake8_requirements.txt
 path:tools/lint/python/pylint_requirements.txt
+path:tools/lint/python/black_requirements.txt
 path:tools/lint/tox/tox_requirements.txt
 
 # Required for the webrender docker image

taskcluster/ci/source-test/mozlint.yml

@@ -217,6 +217,20 @@ py-flake8:
             # moz.configure files are also Python files.
             - '**/*.configure'
 
+py-black:
+    description: black run over the gecko codebase
+    treeherder:
+        symbol: py(black)
+    run:
+        mach: lint -v -l black -f treeherder -f json:/builds/worker/mozlint.json *
+    when:
+        files-changed:
+            - '**/*.py'
+            - 'pyproject.toml'
+            - 'tools/lint/flake8.yml'
+            # moz.configure files are also Python files.
+            # However, we don't currently check them with black
+
 py-pylint:
     description: pylint run over the gecko codebase
     treeherder:

taskcluster/docker/lint/Dockerfile

@@ -36,6 +36,8 @@ ADD topsrcdir/tools/lint/python/pylint_requirements.txt /tmp/pylint_requirements
 ADD topsrcdir/tools/lint/spell/codespell_requirements.txt /tmp/codespell_requirements.txt
 # %include tools/lint/tox/tox_requirements.txt
 ADD topsrcdir/tools/lint/tox/tox_requirements.txt /tmp/tox_requirements.txt
+# %include tools/lint/python/black_requirements.txt
+ADD topsrcdir/tools/lint/python/black_requirements.txt /tmp/black_requirements.txt
 RUN bash /tmp/system-setup.sh
 
 # %include taskcluster/scripts/run-task

taskcluster/docker/lint/system-setup.sh

@@ -1,5 +1,5 @@
 #!/usr/bin/env bash
-# This allows ubuntu-desktop to be installed without human interaction
+# This allows packages to be installed without human interaction
 export DEBIAN_FRONTEND=noninteractive
 
 set -ve
@@ -109,6 +109,14 @@ cd /setup
 
 pip3 install --require-hashes -r /tmp/tox_requirements.txt
 
+###
+# Black Setup
+###
+
+cd /setup
+
+pip3 install --require-hashes -r /tmp/black_requirements.txt
+
 ###
 # rustfmt and clippy
 ###