Add typings for Pipe API

Author: ian-craig

src/index.d.ts

@@ -1,48 +1,164 @@
 export interface Formatter {
-  format(delta: Delta, original: any): string;
+    format(delta: Delta, original: any): string;
 }
 
 export interface Delta {
     [key: string]: any;
     [key: number]: any;
 }
 
-export interface DiffContext {
+export class Context {
+    nested: boolean;
+    exiting?: boolean;
+    options: Config;
+    parent?: PatchContext;
+    childName?: string;
+    children?: PatchContext[];
+    root?: PatchContext;
+    next?: PatchContext;
+    nextAfterChildren?: PatchContext;
+    hasResult: boolean;
+    setResult(result: any): Context;
+    exit(): Context;
+}
+
+export class PatchContext extends Context {
+    pipe: "patch";
+    left: any;
+    delta: Delta;
+}
+
+export class DiffContext extends Context {
+    pipe: "diff";
     left: any;
     right: any;
 }
 
+export class ReverseContext extends Context {
+    pipe: "reverse";
+    delta: Delta;
+}
+
+type FilterContext = PatchContext | DiffContext | ReverseContext;
+
+/**
+ * A plugin which can modify the diff(), patch() or reverse() operations
+ */
+export interface Filter<TContext extends FilterContext> {
+    /**
+     * A function which is called at each stage of the operation and can update the context to modify the result
+     * @param context The current state of the operation
+     */
+    (context: TContext): void;
+
+    /**
+     * A unique name which can be used to insert other filters before/after, or remove/replace this filter
+     */
+    filterName: string;
+}
+
+/**
+ * A collection of Filters run on each diff(), patch() or reverse() operation
+ */
+export class Pipe<TContext extends FilterContext> {
+    /**
+     * Append one or more filters to the existing list
+     */
+    append(...filters: Filter<TContext>[]): void;
+
+    /**
+     * Prepend one or more filters to the existing list
+     */
+    prepend(...filters: Filter<TContext>[]): void;
+
+    /**
+     * Add one ore more filters after the specified filter
+     * @param filterName The name of the filter to insert before
+     * @param filters Filters to be inserted
+     */
+    after(filterName: string, ...filters: Filter<TContext>[]): void;
+
+    /**
+     * Add one ore more filters before the specified filter
+     * @param filterName The name of the filter to insert before
+     * @param filters Filters to be inserted
+     */
+    before(filterName: string, ...filters: Filter<TContext>[]): void;
+
+    /**
+     * Replace the specified filter with one ore more filters
+     * @param filterName The name of the filter to replace
+     * @param filters Filters to be inserted
+     */
+    replace(filterName: string, ...filters: Filter<TContext>[]): void;
+
+    /**
+     * Remove the filter with the specified name
+     * @param filterName The name of the filter to remove
+     */
+    remove(filterName: string): void;
+
+    /**
+     * Remove all filters from this pipe
+     */
+    clear(): void;
+
+    /**
+     * Return array of ordered filter names for this pipe
+     */
+    list(): void;
+}
+
+export class Processor {
+    constructor(options?: Config);
+
+    pipes: {
+        patch: Pipe<PatchContext>;
+        diff: Pipe<DiffContext>;
+        reverse: Pipe<ReverseContext>;
+    };
+}
+
 export interface Config {
     // used to match objects when diffing arrays, by default only === operator is used
-    objectHash?: (item: any) => string;
+    objectHash?: (item: any, index: number) => string;
+
     arrays?: {
         // default true, detect items moved inside the array (otherwise they will be registered as remove+add)
         detectMove: boolean,
         // default false, the value of items moved is not included in deltas
         includeValueOnMove: boolean,
     };
+
     textDiff?: {
         // default 60, minimum string length (left and right sides) to use text diff algorythm: google-diff-match-patch
         minLength: number,
     };
-    /*
-        this optional function can be specified to ignore object properties (eg. volatile data)
-        name: property name, present in either context.left or context.right objects
-        context: the diff context (has context.left and context.right objects)
-    */
+
+    /**
+     * this optional function can be specified to ignore object properties (eg. volatile data)
+     * @param name property name, present in either context.left or context.right objects
+     * @param context the diff context (has context.left and context.right objects)
+     */
+    /**
+     *
+     */
     propertyFilter?: (name: string, context: DiffContext) => boolean;
-    /*
-        default false. if true, values in the obtained delta will be cloned (using jsondiffpatch.clone by default),
-        to ensure delta keeps no references to left or right objects. this becomes useful if you're diffing and patching
-        the same objects multiple times without serializing deltas.
 
-        instead of true, a function can be specified here to provide a custom clone(value)
+    /**
+     *  default false. if true, values in the obtained delta will be cloned (using jsondiffpatch.clone by default),
+     *  to ensure delta keeps no references to left or right objects. this becomes useful if you're diffing and patching
+     *  the same objects multiple times without serializing deltas.
+     *
+     *  instead of true, a function can be specified here to provide a custom clone(value)
      */
     cloneDiffValues?: boolean | ((value: any) => any);
 }
 
 export class DiffPatcher {
-    constructor(options?: any);
+    constructor(options?: Config);
+
+    processor: Processor;
 
     clone: (value: any) => any;
     diff: (left: any, right: any) => Delta | undefined;
@@ -52,9 +168,9 @@ export class DiffPatcher {
 }
 
 export const formatters: {
-  annotated: Formatter;
-  console: Formatter;
-  html: Formatter;
+    annotated: Formatter;
+    console: Formatter;
+    html: Formatter;
 };
 
 export const console: Formatter