Lint Sass files using the rules in stylelint-config-edx

Fixes

package.json

@@ -59,6 +59,8 @@
     "plato": "1.2.2",
     "selenium-webdriver": "3.4.0",
     "sinon": "2.3.5",
-    "squirejs": "^0.1.0"
+    "squirejs": "^0.1.0",
+    "@edx/stylelint-config-edx": "^1.1.0",
+    "stylelint-formatter-pretty": "^1.0.3"
   }
 }

pavelib/paver_tests/test_eslint.py

 """
-Tests for paver quality tasks
+Tests for Paver's Stylelint tasks.
 """
 import unittest
 
@@ -9,13 +9,13 @@ from paver.easy import BuildFailure
 import pavelib.quality
 
 
-class TestPaverESLint(unittest.TestCase):
+class TestPaverStylelint(unittest.TestCase):
     """
-    For testing run_eslint
+    For testing run_stylelint
     """
 
     def setUp(self):
-        super(TestPaverESLint, self).setUp()
+        super(TestPaverStylelint, self).setUp()
 
         # Mock the paver @needs decorator
         self._mock_paver_needs = patch.object(pavelib.quality.run_eslint, 'needs').start()

pavelib/paver_tests/test_stylelint.py

+"""
+Tests for Paver's Stylelint tasks.
+"""
+import ddt
+from mock import MagicMock, patch
+from paver.easy import call_task
+
+from .utils import PaverTestCase
+
+
+@ddt.ddt
+class TestPaverStylelint(PaverTestCase):
+    """
+    Tests for Paver's Stylelint tasks.
+    """
+
+    def setUp(self):
+        super(TestPaverStylelint, self).setUp()
+        pass
+
+    @ddt.data(
+        [0, False],
+        [99, False],
+        [100, True],
+    )
+    @ddt.unpack
+    def test_run_stylelint(self, violations_limit, should_pass):
+        """
+        Verify that the quality task fails with Stylelint violations.
+        """
+        _mock_stylelint_violations = MagicMock(return_value=100)
+        with patch('pavelib.quality._get_stylelint_violations', _mock_stylelint_violations):
+            if should_pass:
+                call_task('pavelib.quality.run_stylelint', options={"limit": violations_limit})
+            else:
+                with self.assertRaises(SystemExit):
+                    call_task('pavelib.quality.run_stylelint', options={"limit": violations_limit})

pavelib/quality.py

+# coding=utf-8
+
 """
 Check code quality using pep8, pylint, and diff_quality.
 """
@@ -6,7 +8,7 @@ import os
 import re
 from string import join
 
-from paver.easy import BuildFailure, cmdopts, needs, sh, task
+from paver.easy import BuildFailure, call_task, cmdopts, needs, sh, task
 
 from openedx.core.djangolib.markup import HTML
 
@@ -189,7 +191,7 @@ def _get_pep8_violations():
         "{report_dir}/pep8.report".format(report_dir=report_dir)
     )
 
-    return (count, violations_list)
+    return count, violations_list
 
 
 def _pep8_violations(report_file):
@@ -315,6 +317,64 @@ def run_eslint(options):
         )
 
 
+def _get_stylelint_violations():
+    """
+    Returns the number of Stylelint violations.
+    """
+    stylelint_report_dir = (Env.REPORT_DIR / "stylelint")
+    stylelint_report = stylelint_report_dir / "stylelint.report"
+    _prepare_report_dir(stylelint_report_dir)
+    formatter = 'node_modules/stylelint-formatter-pretty'
+
+    sh(
+        "stylelint **/*.scss --custom-formatter={formatter} | tee {stylelint_report}".format(
+            formatter=formatter,
+            stylelint_report=stylelint_report,
+        ),
+        ignore_error=True
+    )
+
+    try:
+        return int(_get_count_from_last_line(stylelint_report, "eslint"))
+    except TypeError:
+        raise BuildFailure(
+            "Error. Number of eslint violations could not be found in {eslint_report}".format(
+                eslint_report=stylelint_report
+            )
+        )
+
+
+@task
+@needs('pavelib.prereqs.install_node_prereqs')
+@cmdopts([
+    ("limit=", "l", "limit for number of acceptable violations"),
+])
+@timed
+def run_stylelint(options):
+    """
+    Runs stylelint on Sass files.
+    If limit option is passed, fails build if more violations than the limit are found.
+    """
+    violations_limit = int(getattr(options, 'limit', -1))
+    num_violations = _get_stylelint_violations()
+
+    # Record the metric
+    _write_metric(num_violations, (Env.METRICS_DIR / "stylelint"))
+
+    # Fail if number of violations is greater than the limit
+    if num_violations > violations_limit > -1:
+        raise BuildFailure(
+            "Stylelint failed with too many violations: ({count}).\nThe limit is {violations_limit}.".format(
+                count=num_violations,
+                violations_limit=violations_limit,
+            )
+        )
+    if num_violations > 0:
+        print("Stylelint succeeded with no more violations than {violations_limit}".format(
+            violations_limit=violations_limit,
+        ))
+
+
 @task
 @needs('pavelib.prereqs.install_python_prereqs')
 @cmdopts([
@@ -518,7 +578,7 @@ def _get_count_from_last_line(filename, file_type):
     This will return the number in the last line of a file.
     It is returning only the value (as a floating number).
     """
-    last_line = _get_report_contents(filename, last_line_only=True)
+    last_line = _get_report_contents(filename, last_line_only=True).strip()
     if file_type is "python_complexity":
         # Example of the last line of a complexity report: "Average complexity: A (1.93953443446)"
         regex = r'\d+.\d+'

scripts/all-tests.sh

@@ -13,6 +13,7 @@ set -e
 # Violations thresholds for failing the build
 export PYLINT_THRESHOLD=3600
 export ESLINT_THRESHOLD=9134
+export STYLELINT_THRESHOLD=18431
 
 XSSLINT_THRESHOLDS=`cat scripts/xsslint_thresholds.json`
 export XSSLINT_THRESHOLDS=${XSSLINT_THRESHOLDS//[[:space:]]/}

scripts/circle-ci-tests.sh

@@ -65,6 +65,9 @@ else
             echo "Finding ESLint violations and storing report..."
             paver run_eslint -l $ESLINT_THRESHOLD > eslint.log || { cat eslint.log; EXIT=1; }
 
+            echo "Finding Stylelint violations and storing report..."
+            paver run_stylelint -l $STYLELINT_THRESHOLD > stylelint.log || { cat stylelint.log; EXIT=1; }
+
             # Run quality task. Pass in the 'fail-under' percentage to diff-quality
             paver run_quality -p 100 || EXIT=1
 

scripts/generic-ci-tests.sh

@@ -84,6 +84,8 @@ case "$TEST_SUITE" in
 
         echo "Finding ESLint violations and storing report..."
         paver run_eslint -l $ESLINT_THRESHOLD > eslint.log || { cat eslint.log; EXIT=1; }
+        echo "Finding Stylelint violations and storing report..."
+        paver run_stylelint -l $STYLELINT_THRESHOLD > stylelint.log || { cat stylelint.log; EXIT=1; }
         echo "Running code complexity report (python)."
         paver run_complexity || echo "Unable to calculate code complexity. Ignoring error."
         echo "Running xss linter report."

stylelint.config.js

+module.exports = {
+    extends: '@edx/stylelint-config-edx'
+};