Typescript error "Cannot write file ... because it would overwrite input file."

Question

In my Typescript 2.2.1 project in Visual Studio 2015 Update 3, I am getting hundreds of errors in the error list like:

Cannot write file 'C:/{{my-project}}/node_modules/buffer-shims/index.js' because it would overwrite input file.

It looks like this all the time. It doesn't actually prevent building, and everything works just fine, but the error list is distracting and difficult to locate "real" errors when they occur.

Here is my tsconfig.json file

{
  "compileOnSave": true,
  "compilerOptions": {
    "baseUrl": ".",
    "module": "commonjs",
    "noImplicitAny": true,
    "removeComments": true,
    "sourceMap": true,
    "target": "ES5",
    "forceConsistentCasingInFileNames": true,
    "strictNullChecks": true,
    "allowUnreachableCode": false,
    "allowUnusedLabels": false,
    "noFallthroughCasesInSwitch": true,
    "noImplicitReturns": true,
    "noImplicitThis": true,
    "noUnusedLocals": true,
    "noUnusedParameters": true,

    "typeRoots": [],
    "types": [] //Explicitly specify an empty array so that the TS2 @types modules are not acquired since we aren't ready for them yet.
  },
  "exclude": ["node_modules"]
}

How can I get rid of all these errors?

Answer 1

In my instance, I was using the outDir option but not excluding the destination directory from the inputs:

// Bad
{
    "compileOnSave": true,
    "compilerOptions": {
        "outDir": "./built",
        "allowJs": true,
        "target": "es5",
        "allowUnreachableCode": false,
        "noImplicitReturns": true,
        "noImplicitAny": true,
        "typeRoots": [ "./typings" ],
        "outFile": "./built/combined.js"
    },
    "include": [
        "./**/*"
    ],
    "exclude": [
        "./plugins/**/*",
        "./typings/**/*"
    ]
}

All we have to do is exclude the files in the outDir:

// Good
{
    "compileOnSave": true,
    "compilerOptions": {
        "outDir": "./built",
        "allowJs": true,
        "target": "es5",
        "allowUnreachableCode": false,
        "noImplicitReturns": true,
        "noImplicitAny": true,
        "typeRoots": [ "./typings" ],
        "outFile": "./built/combined.js"
    },
    "include": [
        "./**/*"
    ],
    "exclude": [
        "./plugins/**/*",
        "./typings/**/*",
        "./built/**/*" // This is what fixed it!
    ]
}