Merge pull request #208 from MozillaReality/typescript-proptype-defaults

Handle component property default values correctly

src/Component.d.ts

@@ -4,13 +4,13 @@ import { PropType } from "./Types";
  * Base class for components.
  */
 
-export type ComponentSchemaProp<T> = {
-  default?: T;
-  type: PropType<T>;
+export type ComponentSchemaProp = {
+  default?: any;
+  type: PropType<any, any>;
 };
 
 export type ComponentSchema = {
-  [propName: string]: ComponentSchemaProp<any>;
+  [propName: string]: ComponentSchemaProp;
 };
 
 export class Component<C> {

src/Types.d.ts

@@ -1,29 +1,32 @@
-import { Component } from "./Component";
-
 export type TypeCopyFunction<T> = (src: T, dest: T) => T;
 export type TypeCloneFunction<T> = (value: T) => T;
 
-export interface PropTypeDefinition<T> {
+export interface PropTypeDefinition<T, D> {
   name: string
-  default: T
+  default: D
   copy: TypeCopyFunction<T>
   clone: TypeCloneFunction<T>
 }
 
-export interface PropType<T> extends PropTypeDefinition<T> {
+export interface PropType<T, D> extends PropTypeDefinition<T, D> {
   isType: true
 }
 
-export interface PropTypes {
-  Number: PropType<number>;
-  Boolean: PropType<boolean>;
-  String: PropType<string>;
-  Array: PropType<Array<any>>;
-  Ref: PropType<any>;
-  JSON: PropType<any>;
-}
-
-export const Types: PropTypes;
+export type NumberPropType = PropType<number, number>;
+export type BooleanPropType = PropType<boolean, boolean>;
+export type StringPropType = PropType<string, string>;
+export type ArrayPropType<T> = PropType<Array<T>, []>;
+export type RefPropType<T> = PropType<T, undefined>;
+export type JSONPropType = PropType<any, null>;
+
+export const Types: {
+  Number: NumberPropType,
+  Boolean: BooleanPropType,
+  String: StringPropType,
+  Array: ArrayPropType<any>,
+  Ref: RefPropType<any>,
+  JSON: JSONPropType
+};
 
 export function copyValue<T>(src: T, dest: T): T;
 export function cloneValue<T>(value: T): T;
@@ -41,4 +44,4 @@ export function cloneClonable<T>(value: T): T;
  * Use createType to create custom type definitions.
  * @param typeDefinition An object with create, reset and clear functions for the custom type.
  */
-export function createType<T>(typeDefinition: PropTypeDefinition<T>): PropType<T>
+export function createType<T, D>(typeDefinition: PropTypeDefinition<T, D>): PropType<T, D>

src/Types.js

@@ -3,27 +3,42 @@ export const copyValue = src => src;
 export const cloneValue = src => src;
 
 export const copyArray = (src, dest) => {
-  const srcArray = src;
-  const destArray = dest;
+  if (!src) {
+    return src;
+  }
+
+  if (!dest) {
+    return src.slice();
+  }
 
-  destArray.length = 0;
+  dest.length = 0;
 
-  for (let i = 0; i < srcArray.length; i++) {
-    destArray.push(srcArray[i]);
+  for (let i = 0; i < src.length; i++) {
+    dest.push(dest[i]);
   }
 
-  return destArray;
+  return dest;
 };
 
-export const cloneArray = src => src.slice();
+export const cloneArray = src => src && src.slice();
 
 export const copyJSON = src => JSON.parse(JSON.stringify(src));
 
 export const cloneJSON = src => JSON.parse(JSON.stringify(src));
 
-export const copyCopyable = (src, dest) => dest.copy(src);
+export const copyCopyable = (src, dest) => {
+  if (!src) {
+    return src;
+  }
+
+  if (!dest) {
+    return src.clone();
+  }
+
+  return dest.copy(src);
+};
 
-export const cloneClonable = src => src.clone();
+export const cloneClonable = src => src && src.clone();
 
 export function createType(typeDefinition) {
   var mandatoryProperties = ["name", "default", "copy", "clone"];