[Breaking Change] Typescript 3.7 converts reference paths to tsconfig specified paths breaking multi-project compiles.

Typescript is replacing part of a relative path with one of the paths specified in tsconfig’s path section. This is breaking the projects that rely on this file as they cannot resolve the path.

TypeScript Version: 3.7 Visual Studio Version: Community 2017

Search Terms: Typescirpt paths tsconfig reference paths alias.

Code

In the client project at folder\folder\file.ts

/// <reference path="../../External/Knockout/index.d.ts" />

Becomes (in ClientDeclarations) folder\folder\file.d.ts:

/// <reference types="@Client/external/knockout/index" />

My tsconfig file (folder names with sensitive information are replaced with ***)

{
  "compileOnSave": true,
  "compilerOptions": {
    "module": "amd",
    "target": "es6",
    "lib": [ "es6", "dom" ],
    "sourceMap": true,
    "strict": true,
    "build": true,
    "declaration": true,
    "declarationDir": "../ClientDeclarations",
    "baseUrl": "./",
    "paths": {
      "@Common/*": [ "../Common/*" ],
      "@Server/*": [ "../ServerDeclarations/*" ],
      "@Client/*": [ "./*"]
    }
  },
  "include": [
    "./*",
    "./External/***/koco.ts",
    "./External/***/kocss.ts",
    "./External/***/kopath.ts"
  ],
  "exclude": [
    "node_modules"
  ],
  "references": [
    { "path": "../Common" }
  ]
}

Expected behavior: The path should not be transformed during output.

Actual behavior: The path is transformed to include an @Client reference, which my dependant projects can’t resolve. This did not happen in tsc 3.4.

Additionally all of the casing is altered - meaning that this path would not resolve on linux machines.

Related Issues: I haven’t been able to find any - probably because what I’m trying to look for is called a “path” (in tsconfig) which is a highly overloaded term, making searching for anything related to it almost impossible. It would be nice to call it something like a “path alias” so that searching for related issues was easier.

[huntjosh]

Running into the same issue on another multi-project, only occurs when adding the baseUrl property. Will try the custom branch.

[Griffork]

@sheetalkamat Was that branch included in 4.0?