Merge pull request #788 from wheresrhys/rhys/mocking-in-core-docs

docs: merge fetchHandler docs with mocking and spying page

docs/docs/@fetch-mock/core/mocking-and-spying.md

@@ -1,29 +1,37 @@
 ---
-sidebar_position: 3
+sidebar_position: 1
 ---
 
 # Mocking and spying
 
 These methods allow mocking or spying on the `fetch` implementation used by your application.
 
-Note that these methods are only implemented in `@fetch-mock/core` and are not avilable when using `@fetch-mock/jest`, `@fetch-mock/vitest` etc.... Those libraries provide ways to mock `fetch` that are more idiomatic to their own ecosystem.
+## fetchHandler
 
-## When using global fetch in your application
+`fetchMock.fetchHandler(url, requestInit)`
 
-### mockGlobal()
+A mock implementation of `fetch`.
+
+By default it will error. In order to return responses `.route()`, `.catch()` and other routing methods of `fetchMock` must first be used to add routes to its internal router.
+
+All calls made using `fetchMock.fetchHandler` are recorded in `fetchMock.callHistory`.
+
+You can either pass `fetchMock.fetchHandler` into your choice of mocking library or use the methods below to mock global `fetch`.
+
+## mockGlobal()
 
 Replaces `globalThis.fetch` with `fm.fetchHandler`
 
-### unmockGlobal()
+## unmockGlobal()
 
 Restores `globalThis.fetch` to its original state
 
-### spy(matcher, name)
+## spy(matcher, name)
 
 Falls back to the `fetch` implementation set in `fetchMock.config.fetch` for a specific route (which can be named).
 
-When no arguments are provided it will fallback to the native fetch implementation for all requests, similar to `.catch()`
+When no arguments are provided it will fallback to the native fetch implementation for all requests, similar to `.catch()`.
 
-### spyGlobal()
+## spyGlobal()
 
 Equivalent to calling `.mockGlobal()` followed by `.spy()`

docs/docs/@fetch-mock/core/more-routing-methods.md

@@ -15,6 +15,8 @@ Specifies how to respond to calls to `fetch` that don't match any routes.
 
 It accepts any [response](#api-mockingmock_response) compatible with `.route()`. If no argument is passed, then every unmatched call will receive a `200` response.
 
+See also [.spy()](/fetch-mock/docs/@fetch-mock/core/mocking-and-spying#spymatcher-name)
+
 ## .sticky()
 
 Shorthand for `mock()` which creates a route that persists even when `restore()`, `reset()` or `resetbehavior()` are called;