feat: use array to store paths

packages/classes/mapped-types/tsconfig.spec.json

@@ -3,7 +3,7 @@
   "compilerOptions": {
     "outDir": "../../../dist/out-tsc",
     "module": "commonjs",
-    "types": ["jest", "node"]
+    "types": ["jest", "node", "reflect-metadata"]
   },
   "include": [
     "**/*.spec.ts",

packages/classes/src/lib/storages/class-instance.storage.ts

@@ -1,5 +1,18 @@
 import type { Constructible } from '../types';
 
+/*
+  # Implementation strategy
+  Create a tree of `Map`s, such that indexing the tree recursively (with items
+  of a key array, sequentially), traverses the tree, so that when the key array
+  is exhausted, the tree node we arrive at contains the value for that key
+  array under the guaranteed-unique `Symbol` key `dataSymbol`.
+*/
+
+type DataMap = Map<symbol, number>;
+type PathMap = Map<string, PathMap | DataMap>;
+type ArrayKeyedMap = PathMap | DataMap;
+const DATA_SYMBOL = Symbol('map-data');
+
 /**
  * Internal ClassInstanceStorage
  *
@@ -9,36 +22,36 @@ import type { Constructible } from '../types';
  * @private
  */
 export class ClassInstanceStorage {
-  private depthStorage = new WeakMap<Constructible, Map<string, number>>();
+  private depthStorage = new WeakMap<Constructible, ArrayKeyedMap>();
   private recursiveCountStorage = new WeakMap<
     Constructible,
-    Map<string, number>
+    ArrayKeyedMap
   >();
 
   getDepthAndCount(
     parent: Constructible,
-    member: string
+    member: string[]
   ): [depth?: number, count?: number] {
     return [this.getDepth(parent, member), this.getCount(parent, member)];
   }
 
-  getDepth(parent: Constructible, member: string): number | undefined {
+  getDepth(parent: Constructible, member: string[]): number | undefined {
     return ClassInstanceStorage.getInternal(this.depthStorage, parent, member);
   }
 
-  getCount(parent: Constructible, member: string): number | undefined {
+  getCount(parent: Constructible, member: string[]): number | undefined {
     return ClassInstanceStorage.getInternal(
       this.recursiveCountStorage,
       parent,
       member
     );
   }
 
-  setDepth(parent: Constructible, member: string, depth: number): void {
+  setDepth(parent: Constructible, member: string[], depth: number): void {
     ClassInstanceStorage.setInternal(this.depthStorage, parent, member, depth);
   }
 
-  setCount(parent: Constructible, member: string, count: number): void {
+  setCount(parent: Constructible, member: string[], count: number): void {
     ClassInstanceStorage.setInternal(
       this.recursiveCountStorage,
       parent,
@@ -47,7 +60,7 @@ export class ClassInstanceStorage {
     );
   }
 
-  resetCount(parent: Constructible, member: string): void {
+  resetCount(parent: Constructible, member: string[]): void {
     this.setCount(parent, member, 0);
   }
 
@@ -61,42 +74,80 @@ export class ClassInstanceStorage {
   dispose(): void {
     this.recursiveCountStorage = new WeakMap<
       Constructible,
-      Map<string, number>
+      ArrayKeyedMap
     >();
-    this.depthStorage = new WeakMap<Constructible, Map<string, number>>();
+    this.depthStorage = new WeakMap<Constructible, ArrayKeyedMap>();
   }
 
   private static getInternal(
-    storage: WeakMap<Constructible, Map<string, number>>,
+    storage: WeakMap<Constructible, ArrayKeyedMap>,
     parent: Constructible,
-    member: string
+    member: string[]
   ): number | undefined {
     const parentVal = storage.get(parent);
-    return parentVal ? parentVal.get(member) : undefined;
+    return parentVal ? arrayMapGet(parentVal, member) : undefined;
   }
 
   private static setInternal(
-    storage: WeakMap<Constructible, Map<string, number>>,
+    storage: WeakMap<Constructible, ArrayKeyedMap>,
     parent: Constructible,
-    member: string,
+    member: string[],
     value: number
   ): void {
     if (!storage.has(parent)) {
-      storage.set(parent, new Map<string, number>().set(member, value));
+      storage.set(parent, arrayMapSet(new Map(), member, value))
       return;
     }
 
     if (!this.hasInternal(storage, parent, member)) {
-      storage.get(parent)!.set(member, value);
+      arrayMapSet(storage.get(parent), member, value)
     }
   }
 
   private static hasInternal(
-    storage: WeakMap<Constructible, Map<string, number>>,
+    storage: WeakMap<Constructible, ArrayKeyedMap>,
     parent: Constructible,
-    member: string
+    member: string[]
   ): boolean {
     const parentVal = storage.get(parent);
-    return parentVal ? parentVal.has(member) : false;
+    return parentVal ? arrayMapHas(parentVal, member) : false;
+  }
+}
+
+function arrayMapSet(root: ArrayKeyedMap, path: string[], value: number): ArrayKeyedMap {
+  let map = root;
+  for (const item of path) {
+    let nextMap = (map as PathMap).get(item) as PathMap;
+    if (!nextMap) {
+      // Create next map if none exists
+      nextMap = new Map();
+      (map as PathMap).set(item, nextMap);
+    }
+    map = nextMap;
+  }
+  // Reached end of path.  Set the data symbol to the given value
+  (map as DataMap).set(DATA_SYMBOL, value);
+  return root;
+}
+
+function arrayMapHas(root: ArrayKeyedMap, path: string[]): boolean {
+  let map = root;
+  for (const item of path) {
+    const nextMap = (map as PathMap).get(item);
+    if (nextMap) {
+      map = nextMap;
+    } else {
+      return false;
+    }
+  }
+  return (map as DataMap).has(DATA_SYMBOL);
+}
+
+function arrayMapGet(root: ArrayKeyedMap, path: string[]): number | undefined {
+  let map = root;
+  for (const item of path) {
+    map = (map as PathMap).get(item);
+    if (!map) return undefined;
   }
+  return (map as DataMap).get(DATA_SYMBOL);
 }

packages/classes/src/lib/storages/class-metadata.storage.ts

@@ -1,5 +1,6 @@
 import type { Metadata, MetadataStorage } from '@automapper/types';
 import type { Constructible } from '../types';
+import { isSamePath } from '@automapper/core';
 
 /**
  * Internal ClassMetadataStorage
@@ -17,19 +18,18 @@ export class ClassMetadataStorage implements MetadataStorage<Constructible> {
 
   getMetadata(model: Constructible): Array<Metadata<Constructible>> {
     const metadataList = this.storage.get(model) ?? [];
-    let i = metadataList.length;
 
     // empty metadata
-    if (!i) {
+    if (!metadataList.length) {
       // try to get the metadata on the prototype of the class
       return model.name ? this.getMetadata(Object.getPrototypeOf(model)) : [];
     }
 
     const resultMetadataList: Array<Metadata<Constructible>> = [];
-    while (i--) {
+    for (let i = 0; i < metadataList.length; i++) {
       const metadata = metadataList[i];
       // skip existing
-      if (resultMetadataList.some(([metaKey]) => metaKey === metadata[0])) {
+      if (resultMetadataList.some(([metaKey]) => isSamePath(metaKey, metadata[0]))) {
         continue;
       }
       resultMetadataList.push(metadataList[i]);
@@ -40,9 +40,9 @@ export class ClassMetadataStorage implements MetadataStorage<Constructible> {
 
   getMetadataForKey(
     model: Constructible,
-    key: string
+    key: string[]
   ): Metadata<Constructible> | undefined {
-    return this.getMetadata(model).find(([metaKey]) => metaKey === key);
+    return this.getMetadata(model).find(([metaKey]) => isSamePath(metaKey, key));
   }
 
   addMetadata(model: Constructible, metadata: Metadata<Constructible>): void {
@@ -56,7 +56,7 @@ export class ClassMetadataStorage implements MetadataStorage<Constructible> {
     const merged = [...protoExists, ...exists];
 
     // if already exists, break
-    if (merged.some(([existKey]) => existKey === metadata[0])) {
+    if (merged.some(([existKey]) => isSamePath(existKey, metadata[0]))) {
       return;
     }
 

packages/classes/src/lib/utils/explore-metadata.util.ts

@@ -25,9 +25,9 @@ export function exploreMetadata(
         propertyKey,
         { typeFn, depth, isGetterOnly },
       ] of metadataList) {
-        metadataStorage.addMetadata(model, [propertyKey, typeFn, isGetterOnly]);
+        metadataStorage.addMetadata(model, [[propertyKey], typeFn, isGetterOnly]);
         if (depth != null) {
-          instanceStorage.setDepth(model, propertyKey, depth);
+          instanceStorage.setDepth(model, [propertyKey], depth);
         }
       }
     }

packages/classes/src/lib/utils/instantiate.util.ts

@@ -1,8 +1,10 @@
 import {
+  get,
+  setMutate,
   isDateConstructor,
   isDefined,
   isEmpty,
-  isPrimitiveConstructor,
+  isPrimitiveConstructor
 } from '@automapper/core';
 import type { Dictionary } from '@automapper/types';
 import type { ClassInstanceStorage, ClassMetadataStorage } from '../storages';
@@ -37,10 +39,9 @@ export function instantiate<TModel extends Dictionary<TModel>>(
 
   // initialize a nestedConstructible with empty []
   const nestedConstructible: unknown[] = [];
-  let i = metadata.length;
 
   // reversed loop
-  while (i--) {
+  for (let i = 0; i < metadata.length; i++) {
     // destructure
     const [key, meta, isGetterOnly] = metadata[i];
 
@@ -50,25 +51,27 @@ export function instantiate<TModel extends Dictionary<TModel>>(
     }
 
     // get the value at the current key
-    const valueAtKey = (instance as Record<string, unknown>)[key];
+    const valueAtKey = get(instance as Record<string, unknown>, key);
 
     // call the meta fn to get the metaResult of the current key
     const metaResult = meta();
 
     // if is String, Number, Boolean, Array, assign valueAtKey or undefined
     // null meta means this has any type or an arbitrary object, treat as primitives
     if (isPrimitiveConstructor(metaResult) || metaResult === null) {
-      (instance as Record<string, unknown>)[key] = isDefined(valueAtKey, true)
+      const value = isDefined(valueAtKey, true)
         ? valueAtKey
         : undefined;
+      setMutate(instance as Record<string, unknown>, key, value);
       continue;
     }
 
     // if is Date, assign a new Date value if valueAtKey is defined, otherwise, undefined
     if (isDateConstructor(metaResult)) {
-      (instance as Record<string, unknown>)[key] = isDefined(valueAtKey)
+      const value = isDefined(valueAtKey)
         ? new Date(valueAtKey as number)
         : undefined;
+      setMutate(instance as Record<string, unknown>, key, value);
       continue;
     }
 
@@ -79,15 +82,16 @@ export function instantiate<TModel extends Dictionary<TModel>>(
     // if the value at key is an array
     if (Array.isArray(valueAtKey)) {
       // loop through each value and recursively call instantiate with each value
-      (instance as Record<string, unknown>)[key] = valueAtKey.map((val) => {
+      const value = valueAtKey.map((val) => {
         const [instantiateResultItem] = instantiate(
           instanceStorage,
           metadataStorage,
           metaResult as Constructible,
           val
         );
         return instantiateResultItem;
-      });
+      })
+      setMutate(instance as Record<string, unknown>, key, value);
       continue;
     }
 
@@ -100,14 +104,14 @@ export function instantiate<TModel extends Dictionary<TModel>>(
         metaResult as Constructible,
         valueAtKey as Dictionary<unknown>
       );
-      (instance as Record<string, unknown>)[key] = definedInstantiateResult;
+      setMutate(instance as Record<string, unknown>, key, definedInstantiateResult);
       continue;
     }
 
     // if value is null/undefined but defaultValue is not
     // should assign straightaway
     if (isDefined(defaultValue)) {
-      (instance as Record<string, unknown>)[key] = valueAtKey;
+      setMutate(instance as Record<string, unknown>, key, valueAtKey);
       continue;
     }
 
@@ -117,19 +121,15 @@ export function instantiate<TModel extends Dictionary<TModel>>(
 
     // if no depth, just instantiate with new keyword without recursive
     if (depth === 0) {
-      (instance as Record<string, unknown>)[
-        key
-      ] = new (metaResult as Constructible)();
+      setMutate(instance as Record<string, unknown>, key, new (metaResult as Constructible)());
       continue;
     }
 
     // if depth equals count, meaning instantiate has run enough loop.
     // reset the count then assign with new keyword
     if (depth === count) {
       instanceStorage.resetCount(model, key);
-      (instance as Record<string, unknown>)[
-        key
-      ] = new (metaResult as Constructible)();
+      setMutate(instance as Record<string, unknown>, key, new (metaResult as Constructible)());
       continue;
     }
 
@@ -140,7 +140,7 @@ export function instantiate<TModel extends Dictionary<TModel>>(
       metadataStorage,
       metaResult as Constructible
     );
-    (instance as Record<string, unknown>)[key] = instantiateResult;
+    setMutate(instance as Record<string, unknown>, key, instantiateResult);
   }
 
   // after all, resetAllCount on the current model

packages/classes/src/lib/utils/is-destination-path-on-source.util.ts

@@ -1,11 +1,11 @@
 export function isDestinationPathOnSource(
   sourceProto: Record<string, unknown>
 ) {
-  return (sourceObj: any, sourcePath: string) => {
-    return !(
-      !sourceObj.hasOwnProperty(sourcePath) &&
-      !sourceProto.hasOwnProperty(sourcePath) &&
-      !Object.getPrototypeOf(sourceObj).hasOwnProperty(sourcePath)
+  return (sourceObj: any, sourcePath: string[]) => {
+    return sourcePath.length === 1 && !(
+      !sourceObj.hasOwnProperty(sourcePath[0]) &&
+      !sourceProto.hasOwnProperty(sourcePath[0]) &&
+      !Object.getPrototypeOf(sourceObj).hasOwnProperty(sourcePath[0])
     );
   };
 }

packages/classes/src/lib/utils/is-multipart-source-paths-in-source.util.ts

@@ -1,14 +1,14 @@
 import { isClass } from './is-class.util';
 
 export function isMultipartSourcePathsInSource(
-  dottedSourcePaths: string[],
+  sourcePaths: string[],
   sourceInstance: Record<string, unknown>
 ) {
   return !(
-    dottedSourcePaths.length > 1 &&
-    (!sourceInstance.hasOwnProperty(dottedSourcePaths[0]) ||
-      (sourceInstance[dottedSourcePaths[0]] &&
+    sourcePaths.length > 1 &&
+    (!sourceInstance.hasOwnProperty(sourcePaths[0]) ||
+      (sourceInstance[sourcePaths[0]] &&
         // eslint-disable-next-line @typescript-eslint/ban-types
-        isClass((sourceInstance[dottedSourcePaths[0]] as unknown) as Function)))
+        isClass((sourceInstance[sourcePaths[0]]) as Function)))
   );
 }