patch-db/client/lib/source/mock-source.ts

import { Observable } from "rxjs";
import { map } from "rxjs/operators";
import { Update } from "../types";
import { Source } from "./source";
import { RPCResponse } from "./ws-source";

export class MockSource<T> implements Source<T> {
  constructor(private readonly seed: Observable<Update<T>>) {}

  watch$(): Observable<RPCResponse<Update<T>>> {
    return this.seed.pipe(map((result) => ({ result, jsonrpc: "2.0" })));
  }
}