npm script with just ts-node fails

Question

I have a seemingly simple npm script that is failing but I cannot seem to figure out why. I have the following packages installed globally:

+-- ts-node@8.3.0
+-- tsconfig-paths@3.8.0
+-- typeorm-model-generator@0.3.4
`-- typescript@3.5.2

When I run ts-node from the command line it runs as expected.

In my package.json file I have:

"scripts": {
    "ts_test": "ts-node"
},

When I run npm run ts_test I get the following error:

SyntaxError: Unexpected token } in JSON at position 581
    at JSON.parse (<anonymous>)
    at parse (...\node_modules\tsconfig\src\tsconfig.ts:195:15)
    at readFileSync (...\node_modules\tsconfig\src\tsconfig.ts:181:10)
    at Object.loadSync (...\node_modules\tsconfig\src\tsconfig.ts:151:18)
    at readConfig (...\node_modules\ts-node\src\index.ts:425:18)
    at Object.register (...\node_modules\ts-node\src\index.ts:189:18)
    at Object.<anonymous> (...\node_modules\ts-node\src\_bin.ts:140:17)
    at Module._compile (internal/modules/cjs/loader.js:721:30)
    at Object.Module._extensions..js (internal/modules/cjs/loader.js:732:10)
    at Module.load (internal/modules/cjs/loader.js:620:32)

Any advice on what could cause this error or how to further debug it would be helpful.

Update: Below is my tsconfig file:

{
  "compilerOptions": {
    "lib": [
      "es2017"
    ],    
    "baseUrl": "/",
    "noImplicitReturns": true,
    "noImplicitThis": true,
    "strictNullChecks": true,
    "strictPropertyInitialization": false,
    "moduleResolution": "node",
    "sourceMap": true,
    "target": "es2017",
    "outDir": "lib",
    "emitDecoratorMetadata": true,
    "experimentalDecorators": true,
    /* Enables emit interoperability between CommonJS and ES Modules via creation of namespace objects for all imports. Implies 'allowSyntheticDefaultImports'. */
    "esModuleInterop": true,
  },
  "exclude": [
    "node_modules"
  ]
}

Answer 1

JSON specification doesn't support trailing commas. Parsing of your tsconfig.json is failing because of that. Change your tsconfig.json to

{
  "compilerOptions": {
    "lib": [
      "es2017"
    ],    
    "baseUrl": "/",
    "noImplicitReturns": true,
    "noImplicitThis": true,
    "strictNullChecks": true,
    "strictPropertyInitialization": false,
    "moduleResolution": "node",
    "sourceMap": true,
    "target": "es2017",
    "outDir": "lib",
    "emitDecoratorMetadata": true,
    "experimentalDecorators": true,
    "esModuleInterop": true
  },
  "exclude": [
    "node_modules"
  ]
}