TS Improvements (#1676)

* Do not truncate errors, pretty output

* Introduce helpers for sagas

* Update yarn lock

shared/types/sagaHelpers.d.ts

@@ -0,0 +1,22 @@
+import { Effect } from 'redux-saga/effects';
+
+type ExtPromise<T> = T extends Promise<infer U> ? U : T;
+
+type ExtSaga<T> = T extends IterableIterator<infer U> ? Exclude<U, Effect | Effect[]> : T;
+
+/**
+ * Use this helper to unwrap return types from effects like Call / Apply
+ * In the case of calling a function that returns a promise, this helper will unwrap the
+ * promise and return the type inside it. In the case of calling another saga / generator,
+ * this helper will return the actual return value of the saga / generator, otherwise,
+ * it'll return the original type.
+ *
+ * NOTE 1: When using this to extract the type of a Saga, make sure to remove the `SagaIterator`
+ * return type of the saga if it contains one, since that masks the actual return type of the saga.
+ *
+ * NOTE 2: You will most likely need to use the `typeof` operator to use this helper.
+ * E.g type X = UnwrapEffects<typeof MyFunc/MySaga>
+ */
+export type UnwrapEffects<T> = T extends (...args: any[]) => any
+  ? ExtSaga<ReturnType<T>>
+  : ExtPromise<T>;

tsconfig.json

@@ -18,6 +18,8 @@
     "noEmitOnError": false,
     "noUnusedLocals": true,
     "noUnusedParameters": true,
+    "pretty": true,
+    "noErrorTruncation": true,
     "noImplicitAny": true
   },
   "include": [