Recursive types

[zackify]

Any plans or ideas on how to get this to work with recursive types? I get an error when attempting to use it, Maximum call stack size exceeded I guess for now the alternative is to flatten my data for validation purposes

[ForbesLindesay]

Do you get that error at runtime or at compile time?

I would guess if the error happens at compile time it's probably an issue with typescript-json-schema, which is one of our dependencies. An actual small example that fails would be really helpful for debugging this.

If it happens at runtime, I wonder if your data structure is actually recursive in the sense of referencing itself, which is not the same as a recursive type. i.e. the following should be fine

interface Leaf {
  value: string;
}
interface Branch {
  left: Leaf | Branch;
  right: Leaf | Branch;
}

{"left": {"value": "hello"}, "right": {"left": {"value": "beautiful"}, "right": {"value": "world"}}}

but not if you pass it:

const tree = {left: {value: 'hello'}};
tree.right = tree;
validate(tree);

[zackify]

it is at compile time.

Here's an example:

type Question = {
  name: string;
  options?: Option[];
};

export type Form = {
  questions: Question[];
};

type Option = {
  name: string;
  questions: Question[];
};

npx typescript-json-validator Example.ts Form

In my case I have a schema that has questions, which can have options. Each option can have more questions inside if that option is selected.

Edit: looks like its been mentioned before in that repo: YousefED/typescript-json-schema#33

[ntr-808]

Just checking in to say this issue still occurs, here is a stack trace:

/home/ntr/synth-library/node_modules/typescript-json-schema/node_modules/typescript/lib/typescript.js:39425
                    chain = ts.Debug.checkDefined(getSymbolChain(symbol, meaning, /*endOfChain*/ true));
                                                  ^

RangeError: Maximum call stack size exceeded
    at lookupSymbolChainWorker (/home/ntr/synth-library/node_modules/typescript-json-schema/node_modules/typescript/lib/typescript.js:39425:51)
    at lookupSymbolChain (/home/ntr/synth-library/node_modules/typescript-json-schema/node_modules/typescript/lib/typescript.js:39418:24)
    at symbolToTypeNode (/home/ntr/synth-library/node_modules/typescript-json-schema/node_modules/typescript/lib/typescript.js:39590:29)
    at typeToTypeNodeHelper (/home/ntr/synth-library/node_modules/typescript-json-schema/node_modules/typescript/lib/typescript.js:38764:28)
    at /home/ntr/synth-library/node_modules/typescript-json-schema/node_modules/typescript/lib/typescript.js:38585:106
    at withContext (/home/ntr/synth-library/node_modules/typescript-json-schema/node_modules/typescript/lib/typescript.js:38635:37)
    at Object.typeToTypeNode (/home/ntr/synth-library/node_modules/typescript-json-schema/node_modules/typescript/lib/typescript.js:38585:28)
    at typeToString (/home/ntr/synth-library/node_modules/typescript-json-schema/node_modules/typescript/lib/typescript.js:38552:40)
    at Object.typeToString (/home/ntr/synth-library/node_modules/typescript-json-schema/node_modules/typescript/lib/typescript.js:35213:24)
    at JsonSchemaGenerator.getClassDefinition (/home/ntr/synth-library/node_modules/typescript-json-schema/dist/typescript-json-schema.js:578:32)

and the offending type:

import GeoJSON from 'geojson';

type Uuid = string;

export type Scene = {
    id: Uuid,
    name: string,
    parent: Uuid | null,
    children: Scene[],
    features: GeoJSON.Feature[],
}