Glob support for per pattern tsconfig configuration

It's common to have different configurations for files in the same directory with different name patterns. The most common is file.ts and file.test.ts. We usually have different configurations for test files. For instance the global "jest" type is needed in test files but not in source files.

To separate configuration for test and source we can have two separate tsconfig.json files which "include" only test and source:

// tsconfig.json

{
  "exclude": ["*.test.ts"]
} 

Exclude glob is pending https://github.com/Microsoft/TypeScript/issues/10202

// test.tsconfig.json

{
  "include": ["*.test.ts"],
  "compilerOptions": {
    "types": ["jest"]
  }
} 

But this is not optimal for IDEs and other tsc users.

Glob based tsconfig.json

I'm proposing a glob based tsconfig.json which has different config per glob pattern:

[
        {
                // Shared config
                "compilerOptions": {}
        },
        {
                "include": ["*.test.ts"],
                "compilerOptions": {
                        "lib": ["jest"]
                }
        }
]

Changes to tsconfig.json

• It can be an array of configurations
• Each item in the array can specify include or exclude for fine grained compiler options

Resolving compiler option per file pattern

TODO

Conflicting exclude and include pattern between compiler options

TODO

this way one tsconfig.json can serve for all files with different configs per pattern

TypeScript Version: 2.7
Search Terms:

• TSConfig
• Glob
• Pattern

Start with the proposed tsconfig.json array format and the unresolved sections on resolving compiler options per file pattern and conflicting include/exclude patterns. The issue names no source files or tests, so first define the configuration semantics and conflict behavior before identifying the relevant implementation and test entry points.