Fix Flow typing for Mithril, fix #3359

buildSrc/RollupConfig.js

@@ -219,6 +219,8 @@ export const babelPlugins = [
 	// We technically don't need to have this as we expect async to just work but we rely on bluebird in many places and native async
 	// doesn't care about us redefining global Promise.
 	"@babel/plugin-transform-async-to-generator",
+	"@babel/plugin-proposal-optional-chaining",
+	"@babel/plugin-proposal-nullish-coalescing-operator",
 ]
 export const babelDesktopPlugins = [
 	// Using Flow plugin and not preset to run before class-properties and avoid generating strange property code

flow/libs.js

@@ -267,14 +267,13 @@ declare class ContactFindOptions { // cordova contact plugin
 }
 
 interface Attributes {
-
 	[key: string]: any;
 }
 
 type $Attrs<+T> = $ReadOnly<T>
 
 // Declared at the top level to not import it in all places
-interface MComponent<+Attrs> extends Lifecycle<Attrs> {
+interface MComponent<-Attrs> extends Lifecycle<Attrs> {
 	/** Creates a view out of virtual elements. */
 	view(vnode: Vnode<Attrs>): Children;
 }

package.json

@@ -8,7 +8,7 @@
 	},
 	"type": "module",
 	"scripts": {
-		"flow": "flow; test $? -eq 0 -o $? -eq 2",
+		"flow": "flow --show-all-branches; test $? -eq 0 -o $? -eq 2",
 		"start": "./start-desktop.sh",
 		"test": "cd test && node --icu-data-dir=../node_modules/full-icu test api -c && node --icu-data-dir=../node_modules/full-icu test client",
 		"testapi": "cd test && node --icu-data-dir=../node_modules/full-icu test api",
@@ -33,6 +33,8 @@
 		"@babel/plugin-proposal-object-rest-spread": "7.3.4",
 		"@babel/plugin-syntax-dynamic-import": "7.8.3",
 		"@babel/plugin-transform-async-to-generator": "7.13.0",
+	  	"@babel/plugin-proposal-optional-chaining": "^7.14.5",
+	  	"@babel/plugin-proposal-nullish-coalescing-operator": "^7.14.5",
 		"@babel/preset-flow": "7.14.5",
 		"@rollup/plugin-babel": "5.3.0",
 		"@rollup/plugin-commonjs": "16.0.0",

src/gui/base/DropDownSelectorN.js

@@ -30,7 +30,7 @@ export type DropDownSelectorAttrs<T> = {
 	 * The handler is invoked with the new selected value. The displayed selected value is not changed automatically,
 	 * but the handler is responsible for updating this DropDownSelector. The value is updated immediately, if no selectionChangedHandler is provided
 	 */
-	selectionChangedHandler?: handler<T>,
+	selectionChangedHandler?: ?handler<T>,
 	helpLabel?: lazy<Children>,
 	dropdownWidth?: number,
 	icon?: AllIconsEnum,

src/gui/base/DropdownN.js

@@ -33,7 +33,7 @@ export type DropdownInfoAttrs = {
 /**
  * Renders small info message inside the dropdown.
  */
-const DropdownInfo = pureComponent(({center, bold, info}: DropdownInfoAttrs) => {
+const DropdownInfo = pureComponent<DropdownInfoAttrs>(({center, bold, info}) => {
 	return m(".dropdown-info.text-break.selectable" + (center ? ".center" : "") + (bold ? ".b" : ""), info)
 })
 
@@ -158,11 +158,11 @@ export class DropdownN {
 				},
 				this._visibleChildren().map(child => {
 					if (isDropDownInfo(child)) {
-						return m(DropdownInfo, child)
+						return m(DropdownInfo, downcast<DropdownInfoAttrs>(child))
 					} else if (typeof child.href === 'undefined') {
-						return m(ButtonN, ((child: any): ButtonAttrs))
+						return m(ButtonN, downcast<ButtonAttrs>(child))
 					} else {
-						return m(NavButtonN, ((child: any): NavButtonAttrs))
+						return m(NavButtonN, downcast<NavButtonAttrs>(child))
 					}
 				}))
 		}

src/gui/base/InfoBanner.js

@@ -6,6 +6,7 @@ import m from "mithril"
 import {theme} from "../theme"
 import type {InfoLink, TranslationKey} from "../../misc/LanguageViewModel"
 import {lang} from "../../misc/LanguageViewModel"
+import type {ButtonAttrs} from "./ButtonN"
 import {ButtonN, ButtonType} from "./ButtonN"
 import {NavButtonN} from "./NavButtonN"
 import {mapNullable} from "../../api/common/utils/Utils"
@@ -21,17 +22,12 @@ export const BannerType = Object.freeze({
 
 type BannerTypeEnum = $Values<typeof BannerType>
 
-// Compatible with ButtonAttrs
-export type BannerButtonParams = {
-	label: TranslationKey | lazy<string>,
-	click: () => mixed,
-}
 export type InfoBannerAttrs = {
 	message: TranslationKey | lazy<string>,
 	icon: AllIconsEnum,
 	helpLink?: ?InfoLink,
-	buttons?: ?$ReadOnlyArray<?BannerButtonParams>,
-	type: BannerTypeEnum
+	buttons?: ?$ReadOnlyArray<?ButtonAttrs>,
+	type?: BannerTypeEnum
 }
 
 /**
@@ -69,7 +65,7 @@ export class InfoBanner implements MComponent<InfoBannerAttrs> {
 		])
 	}
 
-	renderIcon(icon: AllIconsEnum, type: BannerTypeEnum): Children {
+	renderIcon(icon: AllIconsEnum, type: ?BannerTypeEnum): Children {
 		return m(Icon, {
 			icon,
 			style: {
@@ -79,11 +75,10 @@ export class InfoBanner implements MComponent<InfoBannerAttrs> {
 		})
 	}
 
-	renderButtons(buttons: $ReadOnlyArray<?BannerButtonParams>): Children {
-		return buttons.filter(Boolean).map(({label, click}) => m(ButtonN, {
-			label,
+	renderButtons(buttons: $ReadOnlyArray<?ButtonAttrs>): Children {
+		return buttons.filter(Boolean).map((attrs) => m(ButtonN, {
+			...attrs,
 			type: ButtonType.Secondary,
-			click,
 		}))
 	}
 
@@ -95,7 +90,8 @@ export class InfoBanner implements MComponent<InfoBannerAttrs> {
 				href: lang.getInfoLink(helpLink),
 				small: true,
 				hideLabel: true,
-				centred: true
+				centred: true,
+				label: "help_label"
 			}))
 	}
 }

src/gui/base/NotificationOverlay.js

@@ -30,9 +30,11 @@ class NotificationOverlay implements MComponent<NotificationOverlayAttrs> {
 }
 
 /**
+ * @param message What will be shown inside notification
+ * @param closeButtonAttrs To define the close button in the notification
  * @param buttons The postpone button is automatically added and does not have to be passed from outside
  */
-export function show(message: MComponent<mixed>, closeButtonAttrs: $Shape<ButtonAttrs>, buttons: Array<ButtonAttrs>) {
+export function show(message: MComponent<void>, closeButtonAttrs: $Shape<ButtonAttrs>, buttons: Array<ButtonAttrs>) {
 	notificationQueue.push({message, buttons, closeButtonAttrs})
 	if (notificationQueue.length > 1) {
 		// another notification is already visible. Next notification will be shown when closing current notification