ci: introduce linting

.editorconfig

@@ -1,13 +1,11 @@
-root = true
-
 [*]
 indent_style = tab
 tab_width = 2
 end_of_line = lf
 charset = utf-8
 trim_trailing_whitespace = true
 insert_final_newline = true
-max_line_length = 100
+max_line_length = 120
 
 [*.yml]
 indent_style = space

.github/workflows/ci.yml

@@ -13,27 +13,27 @@ permissions:
   contents: read
 
 jobs:
-  # ToDo: Configure linter
-  #  lint:
-  #    name: "Lint"
-  #    runs-on: ubuntu-latest
-  #    steps:
-  #      - name: "Checkout"
-  #        uses: actions/checkout@v4
-  #        with:
-  #          fetch-depth: 0
-  #      - name: 'Enable corepack'
-  #        run: corepack enable
-  #      - uses: actions/setup-node@v4
-  #        with:
-  #          node-version: 22
-  #          cache: 'yarn'
-  #
-  #      - name: "Install dependencies"
-  #        run: yarn install --immutable
-  #
-  #      - name: "Lint"
-  #        run: yarn lint -f @react-hookz/gha
+
+  lint:
+    name: "Lint"
+    runs-on: ubuntu-latest
+    steps:
+      - name: "Checkout"
+        uses: actions/checkout@v4
+        with:
+          fetch-depth: 0
+      - name: 'Enable corepack'
+        run: corepack enable
+      - uses: actions/setup-node@v4
+        with:
+          node-version: 22
+          cache: 'yarn'
+
+      - name: "Install dependencies"
+        run: yarn install --immutable
+
+      - name: "Lint"
+        run: yarn lint -f @react-hookz/gha
 
   build:
     name: "Build"
@@ -98,7 +98,7 @@ jobs:
     permissions:
       pull-requests: write
       contents: write
-    needs: [ "test", "build" ]
+    needs: [ "test", "build", "lint" ]
     if: github.actor == 'dependabot[bot]' && github.event_name == 'pull_request'
     steps:
       - uses: fastify/github-action-merge-dependabot@v3
@@ -108,7 +108,7 @@ jobs:
   semantic-release:
     name: "Release"
     runs-on: ubuntu-latest
-    needs: [ "test", "build" ]
+    needs: [ "test", "build", "lint" ]
     if: github.event_name == 'push' || github.event_name == 'workflow_dispatch'
     outputs:
       new-release-published: ${{ steps.release.outputs.new-release-published }}

.husky/pre-commit

@@ -0,0 +1 @@
+yarn lint-staged

.prettierrc.js

@@ -0,0 +1,8 @@
+import ver0Cfg from '@ver0/eslint-config/.prettierrc.js';
+
+/**
+ * @type {import("prettier").Config}
+ */
+export default {
+	...ver0Cfg,
+};

eslint.config.js

@@ -0,0 +1,18 @@
+import {buildConfig} from '@ver0/eslint-config';
+
+/** @typedef {import('eslint').Linter} Linter */
+
+/** @type {Linter.Config[]} */
+const cfg = [
+	...buildConfig({
+		globals: 'node',
+		react: true,
+		vitest: true,
+	}),
+	{
+		files: ['README.md'],
+		language: 'markdown/gfm',
+	},
+];
+
+export default cfg;

package.json

@@ -21,6 +21,9 @@
 	},
 	"license": "MIT",
 	"author": "Anton Zinovyev <xog3@yandex.ru>",
+	"engines": {
+		"node": ">=18"
+	},
 	"type": "module",
 	"files": [
 		"dist"
@@ -31,16 +34,21 @@
 		"postinstall": "husky",
 		"build": "yarn build:clean && yarn tsc -p tsconfig.build.json",
 		"build:clean": "rimraf dist",
+		"lint": "eslint",
+		"lint:fix": "eslint --fix",
 		"test": "vitest --run",
 		"test:coverage": "vitest --run --coverage"
 	},
 	"packageManager": "yarn@4.6.0",
 	"devDependencies": {
 		"@commitlint/cli": "^19.7.1",
 		"@commitlint/config-conventional": "^19.7.1",
+		"@react-hookz/eslint-formatter-gha": "^3.0.3",
 		"@types/react": "^19.0.8",
 		"@types/react-dom": "^19.0.3",
+		"@ver0/eslint-config": "^1.1.1",
 		"@vitest/coverage-v8": "^3.0.5",
+		"eslint": "^9.19.0",
 		"husky": "^9.1.7",
 		"jsdom": "^26.0.0",
 		"lint-staged": "^15.4.3",

src/act.ts

@@ -1,12 +1,13 @@
-import {act as reAct} from "react";
+import {act as reAct} from 'react';
 
-type reactGlobal = typeof globalThis & { IS_REACT_ACT_ENVIRONMENT?: boolean }
+type reactGlobal = typeof globalThis & {IS_REACT_ACT_ENVIRONMENT?: boolean};
 
-
-/* v8 ignore next 7 */
+/* v8 ignore next 9 */
 function getGlobalThis(): reactGlobal {
 	if (typeof globalThis !== 'undefined') return globalThis;
+	// eslint-disable-next-line unicorn/prefer-global-this
 	if (typeof self !== 'undefined') return self;
+	// eslint-disable-next-line unicorn/prefer-global-this
 	if (typeof window !== 'undefined') return window;
 
 	throw new Error('Unable to locate global object');
@@ -20,7 +21,7 @@ function setIsReactEnvironment() {
 
 	return () => {
 		g.IS_REACT_ACT_ENVIRONMENT = initial;
-	}
+	};
 }
 
 /**

src/cleanup.ts

@@ -9,6 +9,7 @@ export async function hooksCleanup() {
 	for (const cb of cbs) {
 		cbs.delete(cb);
 
+		// eslint-disable-next-line no-await-in-loop
 		await cb();
 	}
 }
@@ -18,8 +19,6 @@ export async function hooksCleanup() {
  */
 export function cleanupAdd(cb: CleanupCallback) {
 	cbs.add(cb);
-
-	return () => cleanupRemove(cb);
 }
 
 /**

src/create-hook-renderer.ts

@@ -1,28 +1,31 @@
-import {JSXElementConstructor, ReactNode} from "react";
-import type {RootOptions} from "react-dom/client";
-import {cleanupAdd, cleanupRemove} from "./cleanup.js";
+import type {JSXElementConstructor, ReactNode} from 'react';
+import type {RootOptions} from 'react-dom/client';
+import {cleanupAdd, cleanupRemove} from './cleanup.js';
 
 /**
  * Represents the result of rendering a hook.
  */
-export type ResultValue<T> = {
-	readonly value: undefined;
-	readonly error: Error;
-} | {
-	readonly value: T;
-	readonly error: undefined;
-}
+export type ResultValue<T> =
+	| {
+			readonly value: undefined;
+			readonly error: Error;
+	  }
+	| {
+			readonly value: T;
+			readonly error: undefined;
+	  };
 
 /**
  * Represents the last rendered hook result and all previous results.
  */
 export type ResultValues<T> = ResultValue<T> & {
-	readonly all: ResultValue<T>[];
-}
+	readonly all: Array<ResultValue<T>>;
+};
 
 function newResults<T>() {
-	const results: ResultValue<T>[] = []
+	const results: Array<ResultValue<T>> = [];
 
+	// eslint-disable-next-line @typescript-eslint/consistent-type-assertions
 	const result = {
 		get all() {
 			return [...results];
@@ -35,7 +38,7 @@ function newResults<T>() {
 				return undefined;
 			}
 
-			return results[results.length - 1].value;
+			return results.at(-1)!.value;
 		},
 		get error() {
 			// it is impossible to test it in unit-tests - results are populated
@@ -45,9 +48,9 @@ function newResults<T>() {
 				return undefined;
 			}
 
-			return results[results.length - 1].error;
+			return results.at(-1)!.error;
 		},
-	} as ResultValues<T>
+	} as ResultValues<T>;
 
 	return {
 		result,
@@ -56,7 +59,7 @@ function newResults<T>() {
 		},
 		setError(error: Error) {
 			results.push(Object.freeze({value: undefined, error}));
-		}
+		},
 	};
 }
 
@@ -65,21 +68,24 @@ export type Renderer<Props> = {
 	render(props?: Props): Promise<void>;
 	rerender(props?: Props): Promise<void>;
 	unmount(): Promise<void>;
-}
+};
 
 // Describes the props that renderer creator receives, which allows it to expose callback invocation results.
 export type RendererProps<Props, Result> = {
 	callback(props: Props): Result;
 	setValue(value: Result): void;
 	setError(error: Error): void;
-}
+};
 
 // Describes the renderer creator function that creates a renderer for a specific hook.
-export type RendererCreator<Props, Result, TRenderer extends Renderer<Props>> = (props: RendererProps<Props, Result>, options?: RendererOptions<NoInfer<Props>>) => TRenderer;
+export type RendererCreator<Props, Result, TRenderer extends Renderer<Props>> = (
+	props: RendererProps<Props, Result>,
+	options?: RendererOptions<NoInfer<Props>>
+) => TRenderer;
 export type RendererOptions<Props> = {
 	initialProps?: Props;
-	wrapper?: JSXElementConstructor<{ children: ReactNode }>
-} & Pick<RootOptions, 'onCaughtError' | 'onRecoverableError'>
+	wrapper?: JSXElementConstructor<{children: ReactNode}>;
+} & Pick<RootOptions, 'onCaughtError' | 'onRecoverableError'>;
 
 export function createHookRenderer<Props, Result, TRenderer extends Renderer<Props>>(
 	createRenderer: RendererCreator<Props, Result, TRenderer>
@@ -90,24 +96,26 @@ export function createHookRenderer<Props, Result, TRenderer extends Renderer<Pro
 		// this variable holds previous props, so it is possible to rerender
 		// with previous props preserved
 		let hookProps = options?.initialProps;
-		const {render, rerender, unmount, ...rest} = createRenderer({
-			callback,
-			setValue,
-			setError
-		}, options)
-
+		const {render, rerender, unmount, ...rest} = createRenderer(
+			{
+				callback,
+				setValue,
+				setError,
+			},
+			options
+		);
 
 		await render(hookProps);
 
 		const rerenderHook = async (props?: Props) => {
 			hookProps = props ?? hookProps;
 			await rerender(hookProps);
-		}
+		};
 
 		const unmountHook = async () => {
-			cleanupRemove(unmountHook)
+			cleanupRemove(unmountHook);
 			await unmount();
-		}
+		};
 
 		cleanupAdd(unmountHook);
 
@@ -116,6 +124,6 @@ export function createHookRenderer<Props, Result, TRenderer extends Renderer<Pro
 			rerender: rerenderHook,
 			unmount: unmountHook,
 			...rest,
-		}
-	}
+		};
+	};
 }