[api] Paths not resolved relative to tsconfig #64842

import { API } from "typescript/unstable/sync"
import { createFileSystem } from "typescript/unstable/fs"
const projectDir = "/project";
const api = new API({ cwd: "/somewhere-else" });

// 1. Parse compiler options relative to the project directory.
const { options } = api.parseJsonConfigFileContent(
    {
        compilerOptions: {
            module: "esnext",
            moduleResolution: "bundler",
            noEmit: true,
            types: [],
            paths: { lib: ["./types/lib.d.ts"] },
        },
    },
    { configDirectory: projectDir },
);

// 2. Create a program with those parsed options.
const snapshot = api.createSnapshot({
    createPrograms: [{ rootFiles: [`${projectDir}/main.ts`], compilerOptions: options }],
    fileSystem: createFileSystem([
        [`${projectDir}/main.ts`, `import { x } from "lib";\nexport const y: number = x;\n`],
        [`${projectDir}/types/lib.d.ts`, `export declare const x: number;\n`],
    ]),
});
const diagnostics = snapshot.operation.createdPrograms[0].getSemanticDiagnostics([`${projectDir}/main.ts`]).flat();
api.close();

console.log(`  ${diagnostics.length ? diagnostics.map((d) => `error TS${d.code}: ${d.text}`).join("\n  ") : "OK: 'lib' resolved to /project/types/lib.d.ts"}`);