JSDoc improvements (#100)

## **This PR**:

- [X] Fixes some typos.
- [X] Renames some type parameters to make their intentions more clear.
- [X] Adds JSDocs to some of the newly added utilities.

src/index.ts

@@ -176,7 +176,7 @@ export interface PositiveExpectTypeOf<Actual> extends BaseExpectTypeOf<Actual, {
    * @example
    * <caption>check that properties exist</caption>
    * ```ts
-   * const obj = {a: 1, b: ''}
+   * const obj = { a: 1, b: '' }
    *
    * expectTypeOf(obj).toHaveProperty('a')
    *
@@ -395,7 +395,7 @@ export interface NegativeExpectTypeOf<Actual> extends BaseExpectTypeOf<Actual, {
    * @example
    * <caption>check that properties exist</caption>
    * ```ts
-   * const obj = {a: 1, b: ''}
+   * const obj = { a: 1, b: '' }
    *
    * expectTypeOf(obj).toHaveProperty('a')
    *
@@ -519,9 +519,9 @@ export interface BaseExpectTypeOf<Actual, Options extends {positive: boolean}> {
    * @returns `true`.
    */
   toBeCallableWith: Options['positive'] extends true
-    ? <A extends OverloadParameters<Actual>>(
-        ...args: A
-      ) => ExpectTypeOf<OverloadsNarrowedByParameters<Actual, A>, Options>
+    ? <Args extends OverloadParameters<Actual>>(
+        ...args: Args
+      ) => ExpectTypeOf<OverloadsNarrowedByParameters<Actual, Args>, Options>
     : never
 
   /**
@@ -542,7 +542,7 @@ export interface BaseExpectTypeOf<Actual, Options extends {positive: boolean}> {
    * @returns `true`.
    */
   toBeConstructibleWith: Options['positive'] extends true
-    ? <A extends ConstructorOverloadParameters<Actual>>(...args: A) => true
+    ? <Args extends ConstructorOverloadParameters<Actual>>(...args: Args) => true
     : never
 
   /**
@@ -854,12 +854,12 @@ export type _ExpectTypeOf = {
  * form of a reference or generic type parameter.
  *
  * @example
- * import {foo, bar} from '../foo'
- * import {expectTypeOf} from 'expect-type'
+ * import { foo, bar } from '../foo'
+ * import { expectTypeOf } from 'expect-type'
  *
  * test('foo types', () => {
- *   // make sure `foo` has type {a: number}
- *   expectTypeOf(foo).toMatchTypeOf({a: 1})
+ *   // make sure `foo` has type { a: number }
+ *   expectTypeOf(foo).toMatchTypeOf({ a: 1 })
  *   expectTypeOf(foo).toHaveProperty('a').toBeNumber()
  *
  *   // make sure `bar` is a function taking a string:

src/messages.ts

@@ -33,8 +33,9 @@ export type PrintType<T> =
 
 /**
  * Helper for showing end-user a hint why their type assertion is failing.
- * This swaps "leaf" types with a literal message about what the actual and expected types are.
- * Needs to check for Not<IsAny<Actual>> because otherwise LeafTypeOf<Actual> returns never, which extends everything 🤔
+ * This swaps "leaf" types with a literal message about what the actual and
+ * expected types are. Needs to check for `Not<IsAny<Actual>>` because
+ * otherwise `LeafTypeOf<Actual>` returns `never`, which extends everything 🤔
  */
 export type MismatchInfo<Actual, Expected> =
   And<[Extends<PrintType<Actual>, '...'>, Not<IsAny<Actual>>]> extends true
@@ -96,7 +97,8 @@ const expectNullable = Symbol('expectNullable')
 export type ExpectNullable<T> = {[expectNullable]: T; result: Not<StrictEqualUsingBranding<T, NonNullable<T>>>}
 
 /**
- * Checks if the result of an expecter matches the specified options, and resolves to a fairly readable error messsage if not.
+ * Checks if the result of an expecter matches the specified options, and
+ * resolves to a fairly readable error message if not.
  */
 export type Scolder<
   Expecter extends {result: boolean},