jest.config.ts

import type { Config } from "jest";
import nextJest from "next/jest.js";

const createJestConfig = nextJest({
    // Provide the path to your Next.js app to load next.config.js and .env files in your test environment
    dir: "./",
});

// Add any custom config to be passed to Jest
const config: Config = {
    coverageProvider: "v8",
    testEnvironment: "jsdom",
    setupFilesAfterEnv: ["<rootDir>/jest.setup.ts"],
    moduleNameMapper: {
        "^@/(.*)$": "<rootDir>/src/$1",
        // Handle CSS imports (with CSS modules)
        "^.+\\.module\\.(css|sass|scss)$": "identity-obj-proxy",
        // Handle CSS imports (without CSS modules)
        "^.+\\.(css|sass|scss)$": "<rootDir>/__mocks__/styleMock.js",
        // Handle image imports
        "^.+\\.(png|jpg|jpeg|gif|webp|avif|ico|bmp|svg)$/i": `<rootDir>/__mocks__/fileMock.js`,
    },
    testMatch: [
        "**/__tests__/**/*.[jt]s?(x)",
        "**/?(*.)+(spec|test).[jt]s?(x)",
    ],
    collectCoverageFrom: [
        "src/**/*.{js,jsx,ts,tsx}",
        "!src/**/*.d.ts",
        "!src/**/*.stories.{js,jsx,ts,tsx}",
        "!src/**/__tests__/**",
        "!src/**/__mocks__/**",
        "!src/app/layout.tsx", // Layout is tested through integration tests
    ],
    coverageThreshold: {
        global: {
            branches: 80,
            functions: 85,
            lines: 85,
            statements: 85,
        },
        "./src/app/api/**/*.ts": {
            branches: 90,
            functions: 90,
            lines: 90,
            statements: 90,
        },
    },
    testPathIgnorePatterns: ["<rootDir>/node_modules/", "<rootDir>/.next/"],
    transformIgnorePatterns: [
        "/node_modules/",
        "^.+\\.module\\.(css|sass|scss)$",
    ],
};

// createJestConfig is exported this way to ensure that next/jest can load the Next.js config which is async
export default createJestConfig(config);