Bug 1803829 - Run black linter with line length 99. r=aleca

This aligns black with flake8. A mass-reformat will be needed in a follow-up.

Differential Revision: https://phabricator.services.mozilla.com/D164733

--HG--
extra : moz-landing-system : lando

tools/lint/black.yml

@@ -12,5 +12,5 @@ black:
         - 'tools/lint/python/**'
     type: external
     payload: commlint:lint_wrapper
-    wraps: python.black:lint
+    wraps: commlint:black_lint
     setup: python.black:setup

tools/lint/commlint/__init__.py

@@ -8,6 +8,7 @@ from pathlib import Path
 
 from mozpack import path as mozpath
 from mozlint.types import supported_types
+from mozlint.pathutils import expand_exclusions
 
 COMM_EXCLUSION_FILES = [os.path.join("comm", "tools", "lint", "ThirdPartyPaths.txt")]
 
@@ -60,6 +61,23 @@ def eslint_wrapper(paths, config, **lintargs):
     return rv
 
 
+def black_lint(paths, config, fix=None, **lintargs):
+    from python.black import run_black
+
+    files = list(expand_exclusions(paths, config, lintargs["root"]))
+
+    # prepend "--line-length 99" to files, it will be processed as an argument
+    black_args = ["-l", "99"] + files
+
+    return run_black(
+        config,
+        black_args,
+        fix=fix,
+        log=lintargs["log"],
+        virtualenv_bin_path=lintargs.get("virtualenv_bin_path"),
+    )
+
+
 def lint_wrapper(paths, config, **lintargs):
     _apply_global_excludes(lintargs["root"], config)
     _expand_support_files(lintargs["root"], config)