fix: overrides.extends order when including same rules

close stylelint#6658
kuoruan · Feb 14, 2023 · 2cec3ba · 2cec3ba
1 parent 234bc6e
commit 2cec3ba
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diff --git a/.changeset/thin-candles-cross.md b/.changeset/thin-candles-cross.md
@@ -0,0 +1,5 @@
+---
+"stylelint": patch
+---
+
+Fix overrides.extends order when including same rules
diff --git a/lib/__tests__/applyOverrides.test.js b/lib/__tests__/applyOverrides.test.js
@@ -237,6 +237,30 @@ describe('two matching overrides', () => {
 
 		expect(applied).toEqual(expectedConfig);
 	});
+
+	test('with ordered extends', () => {
+		const config = {
+			extends: ['stylelint-config1'],
+			overrides: [
+				{
+					files: ['*.module.css'],
+					extends: ['stylelint-config2', 'stylelint-config1'],
+				},
+				{
+					files: ['*.css'],
+					extends: ['stylelint-config3'],
+				},
+			],
+		};
+
+		const expectedConfig = {
+			extends: ['stylelint-config2', 'stylelint-config1', 'stylelint-config3'],
+		};
+
+		const applied = applyOverrides(config, __dirname, path.join(__dirname, 'style.module.css'));
+
+		expect(applied).toEqual(expectedConfig);
+	});
 });
 
 describe('no matching overrides', () => {

diff --git a/lib/augmentConfig.js b/lib/augmentConfig.js
@@ -265,8 +265,13 @@ function mergeConfigs(a, b) {
 		}
 
 		if (b.extends) {
-			extendsMerger.extends = [...new Set(extendsMerger.extends.concat(b.extends))];
+			extendsMerger.extends = extendsMerger.extends.concat(b.extends);
 		}
+
+		// Remove duplicates from the array, the last item takes precedence
+		extendsMerger.extends = extendsMerger.extends.filter(
+			(item, index, arr) => arr.lastIndexOf(item) === index,
+		);
 	}
 
 	const rulesMerger = {};