TypeScript 2.0 throws errors from excluded files?

Question

I have a nodeJS project based on this seed project. It has two tsconfig.json files which look like this:

{
    "compilerOptions": {
        "target": "es6",
        "module": "system",
        "moduleResolution": "node",
        "sourceMap": true,
        "emitDecoratorMetadata": true,
        "experimentalDecorators": true,
        "removeComments": false,
        "noImplicitAny": false
    },
    "exclude": [
        "../node_modules"
    ]
}

however, despite the exclude node_modules, I get loads of errors, some of which I've shown below. This has occured since I started using the new npm i @types/xyz approach.

[0] node_modules/@types/core-js/index.d.ts(21,14): error TS2300: Duplicate identifier 'PropertyKey'.

[0] node_modules/@types/core-js/index.d.ts(85,5): error TS2687: All declarations of 'name' must have identical modifiers.

[0] node_modules/@types/core-js/index.d.ts(145,5): error TS2403: Subsequent variable declarations must have the same type. Variable '[Symbol.unscopables]' must be of type '{ copyWithin: boolean; entries: boolean; fill: boolean; find: boolean; findIndex: boolean; keys: ...', but here has type 'any'.

[0] node_modules/@types/core-js/index.d.ts(262,5): error TS2687: All declarations of 'flags' must have identical modifiers.

[0] node_modules/@types/core-js/index.d.ts(276,5): error TS2687: All declarations of 'EPSILON' must have identical modifiers.

[0] node_modules/@types/core-js/index.d.ts(311,5): error TS2687: All declarations of 'MAX_SAFE_INTEGER' must have identical modifiers.

Answer 1

I just ran into this issue after upgrading to ts2.0 with an anguler2 project. I'm using typings for now and have a lot of dependencies. At least on of them is including @types, which duplicates some of the imports. But they are required, I can't just delete the folder / dependency (like other have suggested).

On here I found a pointer to the solution which helped me: https://github.com/Microsoft/TypeScript/issues/11257

Sample from lucassp:

{
    "compilerOptions": {
        "target": "es6",
        "module": "commonjs",
        "moduleResolution": "node",
        "sourceMap": true,
        "emitDecoratorMetadata": true,
        "experimentalDecorators": true,
        "removeComments": false,
        "noImplicitAny": false,
        "types": []
    },
    "exclude": [
        "../node_modules"
    ]
}

I simply had to add "types": [] to the tsconfig.json file, which makes it include none of the types in @types (since all of them are managed by typings currently).

Here's the description of the compiler option from the doc:

--types string[]
List of names of type definitions to include. See @types, –typeRoots and –types for more details.

Microsoft seems to think that @types is the new black typescript definition imports. Read more info on this here.

Eventually I might migrate, but I'll let the dust settle, first.

Answer 2

I was getting the same errors. I am not using the explicit @types/* declarations. However, it looks like updating packages have added those as dependencies.

I got those errors to disappear by removing entries from typings.json. Basically, any declaration that is is under node_modules/@types/ should not be duplicated in typings.json.

Don't forget to run typings prune after updating your typings.json file so extra typings are deleted.