How to fix Option 'resolveJsonModule' is not set but .json files are imported in TypeScript

{
  "compilerOptions": {
    "resolveJsonModule": true,
    // Other options...
  }
}

{
  "compilerOptions": {
    "resolveJsonModule": true,
    "module": "commonjs",
    "esModuleInterop": true
  }
}

{
  "compilerOptions": {
    "resolveJsonModule": true,
    "module": "esnext",
    "moduleResolution": "node"
  }
}

# Check TypeScript version
npx tsc --version

# Or check package.json
npm list typescript

# Update TypeScript
npm install --save-dev typescript@latest

# Or for a specific version
npm install --save-dev typescript@^4.0.0

npx tsc --showConfig | grep resolveJsonModule

// CORRECT - Default import for JSON files
import config from "./config.json";
import packageJson from "../package.json";

// CORRECT - With type annotation (recommended)
import type Config from "./config.json";
import config from "./config.json";

// CORRECT - Destructuring from default import
import { version, name } from "../package.json";

// WRONG - Named imports (JSON files only have default export)
import { version } from "../package.json"; // Error: Module has no exported member 'version'

// CORRECT alternative for named access
import pkg from "../package.json";
const { version, name } = pkg;

// WRONG - Import assertion syntax (TypeScript 4.5+)
import config from "./config.json" assert { type: "json" }; // Not needed with resolveJsonModule

// CORRECT - Simple import
import config from "./config.json";

# Find all tsconfig files in project
find . -name "tsconfig*.json" -type f

# Common tsconfig files:
# - tsconfig.json (main config)
# - tsconfig.app.json (app-specific)
# - tsconfig.node.json (Node.js specific)
# - tsconfig.build.json (build-specific)
# - tsconfig.test.json (test-specific)

// tsconfig.base.json (base configuration)
{
  "compilerOptions": {
    "resolveJsonModule": true,
    // Other shared options...
  }
}

// tsconfig.json (extends base)
{
  "extends": "./tsconfig.base.json",
  "compilerOptions": {
    // Can override or add options
  },
  "include": ["src/**/*"]
}

# Show active configuration
npx tsc --showConfig

# Compile with specific tsconfig
npx tsc -p tsconfig.app.json

{
  "compilerOptions": {
    "resolveJsonModule": true,
    "moduleResolution": "node",
    "module": "commonjs",
    "esModuleInterop": true,
    "allowSyntheticDefaultImports": true
  }
}

{
  "compilerOptions": {
    "resolveJsonModule": true,
    "moduleResolution": "node16",
    "module": "node16"
  }
}

{
  "compilerOptions": {
    "resolveJsonModule": true,
    "moduleResolution": "bundler",
    "module": "esnext"
  }
}

{
  "compilerOptions": {
    "resolveJsonModule": true,
    "baseUrl": "./src",
    "paths": {
      "@config/*": ["config/*"]
    }
  }
}

import config from "@config/app.json";

// vite.config.js
export default {
  // Vite handles JSON imports automatically
}

{
  "name": "my-project",
  "type": "module",
  "scripts": {
    "start": "node --loader ts-node/esm src/index.ts"
  }
}

// jest.config.js
module.exports = {
  transform: {
    '^.+\.tsx?$': 'ts-jest',
  },
  moduleFileExtensions: ['ts', 'tsx', 'js', 'jsx', 'json'],
};

# Install ts-node
npm install --save-dev ts-node

# Run with ts-node
npx ts-node src/index.ts

# Or configure in package.json
{
  "scripts": {
    "start": "ts-node src/index.ts"
  }
}