Merge pull request #204 from ext/feature/jest-dependencies

feat: allow jest dependencies when using jest keyword

README.md

@@ -150,6 +150,35 @@ If your `package.json` contains the `"eslint"` keyword the ESLint packages can b
 }
 ```
 
+### Jest
+
+If your `package.json` contains the `"jest"` keyword the Jest packages can be included as dependencies, e.g. if you publish a sharable config including a plugin you must include `"jest"` as a keyword.
+
+**OK**:
+
+```json
+{
+  "name": "awesome-jest-config",
+  "version": "1.0.0",
+  "keywords": ["jest"],
+  "dependencies": {
+    "babel-jest": "^29.0.0"
+  }
+}
+```
+
+**Fail**:
+
+```json
+{
+  "name": "eslint-config-myfancyconfig",
+  "version": "1.0.0",
+  "dependencies": {
+    "babel-jest": "^29.0.0"
+  }
+}
+```
+
 ### Prettier
 
 If your `package.json` contains the `"prettier"` keyword the Prettier packages can be included as dependencies, e.g. if you publish a sharable config including a plugin you must include `"prettier"` as a keyword.

src/rules/disallowed-dependency.spec.ts

@@ -39,6 +39,11 @@ describe("package list", () => {
 		"html-validate",
 		"html-validate-foobar",
 		"jest",
+		"jest-cli",
+		"jest-transform-stub",
+		"babel-jest",
+		"ts-jest",
+		"@jest/core",
 		"mocha",
 		"prettier",
 		"prettier-config-foobar",
@@ -76,6 +81,20 @@ it("should allow eslint-* if package keywords includes eslint", () => {
 	expect(isDisallowedDependency(eslintPkg, "@scope/eslint-plugin-foobar")).toBeFalsy();
 });
 
+it("should allow jest-* if package keywords includes jest", () => {
+	expect.assertions(6);
+	const eslintPkg: PackageJson = {
+		...pkg,
+		keywords: ["jest"],
+	};
+	expect(isDisallowedDependency(eslintPkg, "jest")).toBeFalsy();
+	expect(isDisallowedDependency(eslintPkg, "jest-cli")).toBeFalsy();
+	expect(isDisallowedDependency(eslintPkg, "jest-transform-stub")).toBeFalsy();
+	expect(isDisallowedDependency(eslintPkg, "babel-jest")).toBeFalsy();
+	expect(isDisallowedDependency(eslintPkg, "ts-jest")).toBeFalsy();
+	expect(isDisallowedDependency(eslintPkg, "@jest/core")).toBeFalsy();
+});
+
 it("should allow prettier-* if package keywords includes prettier", () => {
 	expect.assertions(5);
 	const eslintPkg: PackageJson = {

src/rules/disallowed-dependency.ts

@@ -28,7 +28,6 @@ const disallowedDependencies: RegExp[] = [
 	prefix("gulp"),
 	prefix("html-validate"),
 	prefix("jasmine"),
-	prefix("jest"),
 	prefix("mocha"),
 	prefix("nyc"),
 	prefix("protractor"),
@@ -49,6 +48,14 @@ const disallowedEslint: RegExp[] = [
 	scopedPrefix("eslint-plugin"),
 ];
 
+const disallowedJest: RegExp[] = [
+	exact("jest"),
+	exact("babel-jest"),
+	exact("ts-jest"),
+	prefix("jest-"),
+	scope("@jest"),
+];
+
 const disallowedPrettier: RegExp[] = [
 	exact("prettier"),
 	prefix("prettier-"),
@@ -81,6 +88,11 @@ export function isDisallowedDependency(pkg: PackageJson, dependency: string): bo
 		return true;
 	}
 
+	/* jest-* is allowed only if keywords includes "jest" */
+	if (!keywords.includes("jest") && match(disallowedJest, dependency)) {
+		return true;
+	}
+
 	/* prettier-* is allowed only if keywords includes "prettier" */
 	if (!keywords.includes("prettier") && match(disallowedPrettier, dependency)) {
 		return true;