feat: allow sets to continue to be native javascript arrays

This should help with users migrating to Dyngoose v3

Fixes #667

src/decorator/attribute-types/binary-set.ts

@@ -26,6 +26,8 @@ export class BinarySetAttributeType extends AttributeType<BinarySetValue, Metada
     // returning an empty array means there was a value from DynamoDB with a Set containing no items
     if (value.BS == null) {
       return null
+    } else if (this.metadata?.array === true) {
+      return value.BS
     } else {
       const binarySet: BinarySetValue = new Set()
       value.BS.forEach((item) => {

src/decorator/attribute-types/number-set.ts

@@ -42,10 +42,14 @@ export class NumberSetAttributeType extends AttributeType<NumberSetValue, Metada
   }
 
   fromJSON(values: Array<string | number>): NumberSetValue {
-    const numberSet: NumberSetValue = new Set()
-    values.forEach((item) => {
-      numberSet.add(stringToNumber(item))
-    })
-    return numberSet
+    if (this.metadata?.array === true) {
+      return values.map((item) => stringToNumber(item))
+    } else {
+      const numberSet: NumberSetValue = new Set()
+      values.forEach((item) => {
+        numberSet.add(stringToNumber(item))
+      })
+      return numberSet
+    }
   }
 }

src/decorator/attribute-types/string-set.spec.ts

@@ -0,0 +1,39 @@
+import { expect } from 'chai'
+import { TestableTable } from '../../setup-tests.spec'
+import { isArray, toArray } from 'lodash'
+
+describe('AttributeType/StringSet', () => {
+  let record: TestableTable
+
+  beforeEach(() => {
+    record = TestableTable.new()
+  })
+
+  describe('setting', () => {
+    it('should allow values to be a Set', () => {
+      expect(record.testStringSet).eq(null)
+      record.testStringSet = new Set<string>(['some value'])
+      expect(toArray(record.testStringSet)).deep.eq(['some value'])
+    })
+
+    it('should allow values to be an Array', () => {
+      expect(record.testStringSet).eq(null)
+      record.testStringSet = ['some value'] as any
+      expect(toArray(record.testStringSet)).deep.eq(['some value'])
+    })
+  })
+
+  describe('getting', () => {
+    it('should allow values to read as a Set', () => {
+      expect(record.testStringSet).eq(null)
+      record.testStringSet = new Set<string>(['some value'])
+      expect(record.testStringSet).to.be.instanceOf(Set)
+    })
+
+    it('should allow values to be an Array', () => {
+      expect(record.testStringSetArray).eq(null)
+      record.testStringSetArray = ['some value']
+      expect(isArray(record.testStringSetArray)).eq(true)
+    })
+  })
+})

src/decorator/attribute-types/string-set.ts

@@ -30,6 +30,8 @@ export class StringSetAttributeType extends AttributeType<StringSetValue, Metada
     // returning an empty array means there was a value from DynamoDB with a Set containing no items
     if (value.SS == null) {
       return null
+    } else if (this.metadata?.array === true) {
+      return value.SS
     } else {
       const stringSet: StringSetValue = new Set()
       value.SS.forEach((item) => {

src/metadata/attribute-types/binary-set.metadata.ts

@@ -1,6 +1,10 @@
 import { type AttributeMetadata } from '../attribute'
 
-export type BinarySetValue = Set<Uint8Array>
+export type BinarySetValue = Set<Uint8Array> | Uint8Array[]
 
 export interface BinarySetAttributeMetadata extends AttributeMetadata<BinarySetValue> {
+  /**
+   * Return a native JavaScript array, rather than a Set.
+   */
+  array?: boolean
 }

src/metadata/attribute-types/number-set.metadata.ts

@@ -1,7 +1,11 @@
 import { type AttributeMetadata } from '../attribute'
 import { type NumberValue } from './number.metadata'
 
-export type NumberSetValue = Set<NumberValue>
+export type NumberSetValue = Set<NumberValue> | number[]
 
 export interface NumberSetAttributeMetadata extends AttributeMetadata<NumberSetValue> {
+  /**
+   * Return a native JavaScript array, rather than a Set.
+   */
+  array?: boolean
 }

src/metadata/attribute-types/string-set.metadata.ts

@@ -1,9 +1,10 @@
 import { type AttributeMetadata } from '../attribute'
 
-export type StringSetValue = Set<string>
+export type StringSetValue = Set<string> | string[]
 
 export interface StringSetAttributeMetadata extends AttributeMetadata<StringSetValue> {
-  trim?: boolean
-  lowercase?: boolean
-  uppercase?: boolean
+  /**
+   * Return a native JavaScript array, rather than a Set.
+   */
+  array?: boolean
 }

src/setup-tests.spec.ts

@@ -53,6 +53,9 @@ export class TestableTable extends Dyngoose.Table {
   @Dyngoose.Attribute.StringSet()
   public testStringSet: Set<string>
 
+  @Dyngoose.Attribute.StringSet({ array: true })
+  public testStringSetArray: string[]
+
   @Dyngoose.Attribute.String({ lowercase: true })
   public lowercaseString: string