add a flow definition file

src/index.js

@@ -64,9 +64,9 @@ type Kicker = {
   html: () => Promise<SimpleResponse>
 }
 
-export type CallbackFormat = (form: HTMLFormElement, kicker: Kicker, req: SimpleRequest) => void | Promise<void>
+export type RemoteFormHandler = (form: HTMLFormElement, kicker: Kicker, req: SimpleRequest) => void | Promise<void>
 
-let selectorSet: ?SelectorSet<CallbackFormat>
+let selectorSet: ?SelectorSet<RemoteFormHandler>
 
 const afterHandlers = []
 const beforeHandlers = []
@@ -79,15 +79,15 @@ export function beforeRemote(fn: (form: HTMLFormElement) => mixed) {
   beforeHandlers.push(fn)
 }
 
-export function remoteForm(selector: string, fn: CallbackFormat) {
+export function remoteForm(selector: string, fn: RemoteFormHandler) {
   if (!selectorSet) {
     selectorSet = new SelectorSet()
     document.addEventListener('submit', handleSubmit)
   }
   selectorSet.add(selector, fn)
 }
 
-export function remoteUninstall(selector: string, fn: CallbackFormat) {
+export function remoteUninstall(selector: string, fn: RemoteFormHandler) {
   if (selectorSet) {
     selectorSet.remove(selector, fn)
   }

src/index.js.flow

@@ -0,0 +1,25 @@
+/* flow strict */
+
+declare module '@github/remote-form' {
+  declare type Kicker = {
+    text: () => Promise<SimpleResponse>,
+    json: () => Promise<SimpleResponse>,
+    html: () => Promise<SimpleResponse>
+  }
+
+  declare export type SimpleResponse = {
+    url: string,
+    status: number,
+    statusText: ?string,
+    headers: Headers,
+    text: string,
+    json: {[string]: any},
+    html: DocumentFragment
+  }
+  declare export type RemoteFormHandler = (form: HTMLFormElement, kicker: Kicker, req: SimpleRequest) => void | Promise<void>;
+
+  declare export function afterRemote(fn: (form: HTMLFormElement) => mixed): void;
+  declare export function beforeRemote(fn: (form: HTMLFormElement) => mixed): void;
+  declare export function remoteForm(selector: string, fn: RemoteFormHandler): void;
+  declare export function remoteUninstall(selector: string, fn: RemoteFormHandler): void;
+}