Clean up regressions found in Kibana testing

src/components/common.ts

@@ -32,6 +32,26 @@ export type PropsOf<C> = C extends SFC<infer SFCProps>
   ? ComponentProps
   : never;
 
+// Utility methods for ApplyClassComponentDefaults
+type ExtractDefaultProps<T> = T extends { defaultProps: infer D } ? D : never;
+type ExtractProps<
+  C extends new (...args: any) => any,
+  IT = InstanceType<C>
+> = IT extends Component<infer P> ? P : never;
+
+/**
+ * Because of how TypeScript's LibraryManagedAttributes is designed to handle defaultProps (https://www.typescriptlang.org/docs/handbook/release-notes/typescript-3-0.html#support-for-defaultprops-in-jsx)
+ * we can't directly export the props definition as the defaulted values are not made optional,
+ * because it isn't processed by LibraryManagedAttributes. To get around this, we:
+ * - remove the props which have default values applied
+ * - export (Props - Defaults) & Partial<Defaults>
+ */
+export type ApplyClassComponentDefaults<
+  C extends new (...args: any) => any,
+  D = ExtractDefaultProps<C>,
+  P = ExtractProps<C>
+> = Omit<P, keyof D> & Partial<D>;
+
 /*
 https://github.com/Microsoft/TypeScript/issues/28339
 Problem: Pick and Omit do not distribute over union types, which manifests when

src/components/date_picker/date_picker.tsx

@@ -9,7 +9,7 @@ import { EuiFormControlLayoutIconsProps } from '../form/form_control_layout/form
 import { EuiErrorBoundary } from '../error_boundary';
 
 import { EuiI18nConsumer } from '../context';
-import { CommonProps } from '../common';
+import { ApplyClassComponentDefaults, CommonProps } from '../common';
 
 // @ts-ignore the type is provided by react-datepicker.d.ts
 import { ReactDatePicker as _ReactDatePicker } from '../../../packages';
@@ -72,9 +72,13 @@ interface EuiExtendedDatePickerProps extends ReactDatePickerProps {
   showIcon?: boolean;
 }
 
-export type EuiDatePickerProps = CommonProps & EuiExtendedDatePickerProps;
+type _EuiDatePickerProps = CommonProps & EuiExtendedDatePickerProps;
 
-export class EuiDatePicker extends Component<EuiDatePickerProps> {
+export type EuiDatePickerProps = ApplyClassComponentDefaults<
+  typeof EuiDatePicker
+>;
+
+export class EuiDatePicker extends Component<_EuiDatePickerProps> {
   static defaultProps = {
     adjustDateOnChange: true,
     dateFormat: euiDatePickerDefaultDateFormat,

src/components/date_picker/index.ts

@@ -19,6 +19,7 @@ export {
   RelativeDateMode,
   NowDateMode,
   DateMode,
+  OnRefreshChangeProps,
   ShortDate,
   RelativeParts,
   RelativeOption,

src/components/date_picker/super_date_picker/index.ts

@@ -5,6 +5,8 @@ export { AsyncInterval } from './async_interval';
 export {
   EuiSuperDatePicker,
   EuiSuperDatePickerProps,
+  OnTimeChangeProps,
+  OnRefreshProps,
 } from './super_date_picker';
 
 export {

src/components/date_picker/super_date_picker/super_date_picker.tsx

@@ -33,12 +33,12 @@ import { LocaleSpecifier } from 'moment'; // eslint-disable-line import/named
 
 export { prettyDuration, commonDurationRanges };
 
-interface OnTimeChangeProps extends DurationRange {
+export interface OnTimeChangeProps extends DurationRange {
   isInvalid: boolean;
   isQuickSelection: boolean;
 }
 
-interface OnRefreshProps extends DurationRange {
+export interface OnRefreshProps extends DurationRange {
   refreshInterval: number;
 }
 

src/components/date_picker/types.ts

@@ -49,10 +49,12 @@ export interface RelativeOption {
   value: TimeUnitId | TimeUnitFromNowId;
 }
 
-export type ApplyRefreshInterval = (args: {
-  isPaused?: boolean;
+export type OnRefreshChangeProps = {
+  isPaused: boolean;
   refreshInterval: number;
-}) => void;
+};
+
+export type ApplyRefreshInterval = (args: OnRefreshChangeProps) => void;
 
 export interface QuickSelect {
   timeTense: string;