fix(rules): respect keyword setting for scope-empty (#11)

*  add related regression tests
*  default to "never" keyword
*  correctly negate rule result and message for "always"

closes #10

Author: marionebl

package.json

@@ -17,12 +17,16 @@
     "commitmsg": "node distribution/cli.js --edit",
     "changelog": "conventional-changelog --preset angular --infile changelog.md --same-file --output-unreleased",
     "push": "git push && git push --tags && hub release create \"v$npm_package_version\" --message=\"v$npm_package_version\n$(conventional-changelog -p angular)\" && npm publish",
-    "test": "eslint *.js && jsonlint-cli *.json && node distribution/cli.js --from=HEAD~1",
+    "test": "eslint *.js && jsonlint-cli *.json && node distribution/cli.js --from=HEAD~1 && ava",
     "preversion": "npm run build && npm test",
     "release": "npm version --no-git-tag-version $(conventional-recommended-bump -p angular)",
     "version": "npm run changelog && git add .",
     "postversion": "git commit -m \"chore(release): v$npm_package_version\n$(conventional-changelog -p angular)\" && git tag -a v$npm_package_version -m \"$(conventional-changelog -p angular)\""
   },
+  "ava": {
+    "babel": "inherit",
+    "require": ["babel-register"]
+  },
   "config": {
     "commitizen": {
       "path": "cz-conventional-changelog-lint"
@@ -50,6 +54,7 @@
   },
   "license": "MIT",
   "devDependencies": {
+    "ava": "0.15.2",
     "babel": "6.5.1",
     "babel-cli": "6.4.0",
     "babel-eslint": "5.0.0",

source/rules/scope-empty.js

@@ -1,12 +1,13 @@
 import ensureNotEmpty from '../library/ensure-not-empty';
 
-export default (parsed, when) => {
-	const negated = when === 'never';
+export default (parsed, when = 'never') => {
+	const negated = when === 'always';
+	const result = ensureNotEmpty(parsed.scope);
 	return [
-		ensureNotEmpty(parsed.scope),
+		negated ? !result : result,
 		[
 			'scope',
-			negated ? 'may not' : 'must',
+			negated ? 'must' : 'may not',
 			'be empty'
 		]
 		.filter(Boolean)

test/rules/scope-empty.js

@@ -0,0 +1,69 @@
+import test from 'ava';
+import scopeEmpty from '../../source/rules/scope-empty';
+import {sync as parse} from 'conventional-commits-parser';
+
+const messages = {
+	plain: 'foo(bar): baz',
+	superfluous: 'foo(): baz',
+	empty: 'foo: baz'
+};
+
+const parsed = {
+	plain: parse(messages.plain),
+	superfluous: parse(messages.superfluous),
+	empty: parse(messages.empty)
+};
+
+test('scope-empty with plain message', t => {
+	const [actual] = scopeEmpty(parsed.plain);
+	const expected = true;
+	t.deepEqual(actual, expected, 'it should succeed for empty keyword');
+});
+
+test('scope-empty with plain message', t => {
+	const [actual] = scopeEmpty(parsed.plain, 'never');
+	const expected = true;
+	t.deepEqual(actual, expected, 'it should succeed for "never"');
+});
+
+test('scope-empty with plain message', t => {
+	const [actual] = scopeEmpty(parsed.plain, 'always');
+	const expected = false;
+	t.deepEqual(actual, expected, 'it should fail for "always"');
+});
+
+test('scope-empty with superfluous message', t => {
+	const [actual] = scopeEmpty(parsed.superfluous);
+	const expected = false;
+	t.deepEqual(actual, expected, 'it should fail for empty keyword');
+});
+
+test('scope-empty with superfluous message', t => {
+	const [actual] = scopeEmpty(parsed.superfluous, 'never');
+	const expected = false;
+	t.deepEqual(actual, expected, 'it should fail for "never"');
+});
+
+test('scope-empty with superfluous message', t => {
+	const [actual] = scopeEmpty(parsed.superfluous, 'always');
+	const expected = true;
+	t.deepEqual(actual, expected, 'it should fail for "always"');
+});
+
+test('scope-empty with empty message', t => {
+	const [actual] = scopeEmpty(parsed.empty);
+	const expected = false;
+	t.deepEqual(actual, expected, 'it should fail for empty keyword');
+});
+
+test('scope-empty with empty message', t => {
+	const [actual] = scopeEmpty(parsed.empty, 'never');
+	const expected = false;
+	t.deepEqual(actual, expected, 'it should fail for "never"');
+});
+
+test('scope-empty with empty message', t => {
+	const [actual] = scopeEmpty(parsed.empty, 'always');
+	const expected = true;
+	t.deepEqual(actual, expected, 'it should fail for "always"');
+});