`Unexpected key type "unknown" for this node. (expected "UnionType" or "StringType")` when using PickDeep from type-fest

[crycode-de]

Hi,

I'm trying to migrate from typescript-json-schema to ts-json-schema-generator but I'm stuck with an error:

Error: Unexpected key type "unknown" for this node. (expected "UnionType" or "StringType")

Figured out it's related to the PickDeep type from type-fest which I'm using in my project.

See example and full error below.

Any ideas how to solve this issue?

Simple example to reproduce the issue

Install dependencies:

npm install ts-json-schema-generator type-fest typescript

Create a example.ts file:

import type { PickDeep } from 'type-fest';

export interface SomeTest {
  a: string;
  b: string;
  c: {
    c1: string;
    c2: string;
  };
};

export type SomePicked = PickDeep<SomeTest, 'a' | 'c.c1'>;

Try to create the schema:

./node_modules/.bin/ts-json-schema-generator --path example.ts --type 'SomePicked'
/tmp/tmp.tEprWf2fAX/node_modules/type-fest/source/internal/object.d.ts:36:6 - error TSJ - 105: Unexpected key type "unknown" for this node. (expected "UnionType" or "StringType")

36    : {[_ in Key]: Value};
        ~~~~~~~~~~~~~~~~~~~

Error: Unexpected key type "unknown" for this node. (expected "UnionType" or "StringType")
    at MappedTypeNodeParser.createType (/tmp/tmp.tEprWf2fAX/node_modules/ts-json-schema-generator/dist/src/NodeParser/MappedTypeNodeParser.js:76:15)
    at ChainNodeParser.createType (/tmp/tmp.tEprWf2fAX/node_modules/ts-json-schema-generator/dist/src/ChainNodeParser.js:31:49)
    at ConditionalTypeNodeParser.createType (/tmp/tmp.tEprWf2fAX/node_modules/ts-json-schema-generator/dist/src/NodeParser/ConditionalTypeNodeParser.js:48:49)
    at ChainNodeParser.createType (/tmp/tmp.tEprWf2fAX/node_modules/ts-json-schema-generator/dist/src/ChainNodeParser.js:31:49)
    at ConditionalTypeNodeParser.createType (/tmp/tmp.tEprWf2fAX/node_modules/ts-json-schema-generator/dist/src/NodeParser/ConditionalTypeNodeParser.js:48:49)
    at ChainNodeParser.createType (/tmp/tmp.tEprWf2fAX/node_modules/ts-json-schema-generator/dist/src/ChainNodeParser.js:31:49)
    at TypeAliasNodeParser.createType (/tmp/tmp.tEprWf2fAX/node_modules/ts-json-schema-generator/dist/src/NodeParser/TypeAliasNodeParser.js:36:43)
    at AnnotatedNodeParser.createType (/tmp/tmp.tEprWf2fAX/node_modules/ts-json-schema-generator/dist/src/NodeParser/AnnotatedNodeParser.js:29:47)
    at ExposeNodeParser.createType (/tmp/tmp.tEprWf2fAX/node_modules/ts-json-schema-generator/dist/src/ExposeNodeParser.js:24:45)
    at CircularReferenceNodeParser.createType (/tmp/tmp.tEprWf2fAX/node_modules/ts-json-schema-generator/dist/src/CircularReferenceNodeParser.js:22:43)

[arthurfiorette]

@domoritz would be good to add some type fest utilities to our test suite.

[rgilsimoes]

I also have this error:

Unexpected key type "alias-676275443-11569-11849-676275443-0-12689" for this node. (expected "UnionType" or "StringType")

Originating type:

export type MyRecordType = Partial<Record<string, MyEspecialType>>;