Avoid nested ternaries.

Author: ghengeveld

packages/react-async/src/useAsync.js

@@ -166,26 +166,22 @@ const useAsyncFetch = (input, init, { defer, json, ...options } = {}) => {
   const accept = headers["Accept"] || headers["accept"] || (headers.get && headers.get("accept"))
   const doFetch = (input, init) => globalScope.fetch(input, init).then(parseResponse(accept, json))
   const isDefer =
-    typeof defer === "boolean" ? defer : ~["POST", "PUT", "PATCH", "DELETE"].indexOf(method)
+    typeof defer === "boolean" ? defer : ["POST", "PUT", "PATCH", "DELETE"].indexOf(method) !== -1
   const fn = isDefer ? "deferFn" : "promiseFn"
-  const identity = JSON.stringify({ input, init, fn })
+  const identity = JSON.stringify({ input, init, isDefer })
   const state = useAsync({
     ...options,
     [fn]: useCallback(
-      isDefer
-        ? ([override], _, { signal }) =>
-            doFetch(input, {
-              signal,
-              ...// override is a function, call it with init
-              (typeof override === "function"
-                ? override(init)
-                : // override is an Event or SyntheticEvent - do not spread
-                "preventDefault" in override
-                ? init
-                : // otherwise, spread override over init
-                  { ...init, ...override }),
-            })
-        : (_, { signal }) => doFetch(input, { signal, ...init }),
+      (arg1, arg2, arg3) => {
+        const [override, signal] = arg3 ? [arg1[0], arg3.signal] : [undefined, arg2.signal]
+        if (typeof override === "object" && "preventDefault" in override) {
+          // Don't spread Events or SyntheticEvents
+          return doFetch(input, { signal, ...init })
+        }
+        return typeof override === "function"
+          ? doFetch(input, { signal, ...override(init) })
+          : doFetch(input, { signal, ...init, ...override })
+      },
       [identity] // eslint-disable-line react-hooks/exhaustive-deps
     ),
   })