Commits on Jul 27, 2022

1. Update lodash tests for TS 4.8 …

   Typescript 4.8 now prefers the asserted type in type predicate narrowing
   in the rare case where both types are assignable to each other. Previously it
   preferred the type of the provided parameter.
   
   Usually this is desired, since type predicates
   are essentially type assertions. For example, narrowing `unknown` to a
   specific type is very common. But in _.isFunction, the intent is to
   keep the original signature when narrowing a union:
   
   ```ts
   declare const value: number | (() => void);
   if (_.isFunction(value)) {
      value; // $ExpectType () => void
   }
   ```
   
   Unfortunately functions that return void are assignable to functions
   that return any *and vice versa*, so the new result is that `value` is
   narrowed to isFunctions' return type:
   
   ```ts
   declare const value: number | (() => void);
   if (_.isFunction(value)) {
      value; // $ExpectType (...args: any[]) => any
   }
   ```
   
   I've updated the tests to reflect that. This change doesn't apply to
   functions that return types besides void, but the tests happen to use
   such a function.

   

   sandersn committed Jul 27, 2022
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