fix: permit BSON types to be created without new (#424)

Reverts a change that upgraded the BSON types to es6 classes
preventing types from being constructed without using new.

NODE-3064

Author: nbbeeken

.eslintignore

@@ -2,3 +2,5 @@ dist/
 node_modules/
 docs/
 types/
+lib/
+*.d.ts

rollup.config.js

@@ -10,7 +10,7 @@ const tsConfig = {
   checkJs: false,
   strict: true,
   alwaysStrict: true,
-  target: 'ES2017',
+  target: 'es5',
   module: 'commonjs',
   moduleResolution: 'node',
   lib: ['ES2017', 'ES2020.BigInt', 'ES2017.TypedArrays'],

src/binary.ts

@@ -50,15 +50,17 @@ export class Binary {
   /** User BSON type */
   static readonly SUBTYPE_USER_DEFINED = 128;
 
-  buffer: Buffer;
-  sub_type: number;
-  position: number;
+  buffer!: Buffer;
+  sub_type!: number;
+  position!: number;
 
   /**
    * @param buffer - a buffer object containing the binary data.
    * @param subType - the option binary type.
    */
   constructor(buffer?: string | BinarySequence, subType?: number) {
+    if (!(this instanceof Binary)) return new Binary(buffer, subType);
+
     if (
       !(buffer == null) &&
       !(typeof buffer === 'string') &&

src/code.ts

@@ -13,13 +13,15 @@ export interface CodeExtended {
 export class Code {
   _bsontype!: 'Code';
 
-  code: string | Function;
+  code!: string | Function;
   scope?: Document;
   /**
    * @param code - a string or function.
    * @param scope - an optional scope for the function.
    */
   constructor(code: string | Function, scope?: Document) {
+    if (!(this instanceof Code)) return new Code(code, scope);
+
     this.code = code;
     this.scope = scope;
   }

src/db_ref.ts

@@ -22,17 +22,19 @@ export function isDBRefLike(value: unknown): value is DBRefLike {
 export class DBRef {
   _bsontype!: 'DBRef';
 
-  collection: string;
-  oid: ObjectId;
+  collection!: string;
+  oid!: ObjectId;
   db?: string;
-  fields: Document;
+  fields!: Document;
 
   /**
    * @param collection - the collection name.
    * @param oid - the reference ObjectId.
    * @param db - optional db name, if omitted the reference is local to the current db.
    */
   constructor(collection: string, oid: ObjectId, db?: string, fields?: Document) {
+    if (!(this instanceof DBRef)) return new DBRef(collection, oid, db, fields);
+
     // check if namespace has been provided
     const parts = collection.split('.');
     if (parts.length === 2) {

src/decimal128.ts

@@ -165,10 +165,12 @@ export interface Decimal128Extended {
 export class Decimal128 {
   _bsontype!: 'Decimal128';
 
-  readonly bytes: Buffer;
+  readonly bytes!: Buffer;
 
   /** @param bytes - a buffer containing the raw Decimal128 bytes in little endian order */
   constructor(bytes: Buffer) {
+    if (!(this instanceof Decimal128)) return new Decimal128(bytes);
+
     this.bytes = bytes;
   }
 

src/double.ts

@@ -12,13 +12,15 @@ export interface DoubleExtended {
 export class Double {
   _bsontype!: 'Double';
 
-  value: number;
+  value!: number;
   /**
    * Create a Double type
    *
    * @param value - the number we want to represent as a double.
    */
   constructor(value: number) {
+    if (!(this instanceof Double)) return new Double(value);
+
     if ((value as unknown) instanceof Number) {
       value = value.valueOf();
     }

src/int_32.ts

@@ -12,13 +12,15 @@ export interface Int32Extended {
 export class Int32 {
   _bsontype!: 'Int32';
 
-  value: number;
+  value!: number;
   /**
    * Create an Int32 type
    *
    * @param value - the number we want to represent as an int32.
    */
   constructor(value: number | string) {
+    if (!(this instanceof Int32)) return new Int32(value);
+
     if ((value as unknown) instanceof Number) {
       value = value.valueOf();
     }

src/long.ts

@@ -82,17 +82,17 @@ export class Long {
   /**
    * The high 32 bits as a signed value.
    */
-  high: number;
+  high!: number;
 
   /**
    * The low 32 bits as a signed value.
    */
-  low: number;
+  low!: number;
 
   /**
    * Whether unsigned or not.
    */
-  unsigned: boolean;
+  unsigned!: boolean;
 
   /**
    * Constructs a 64 bit two's-complement integer, given its low and high 32 bit values as *signed* integers.
@@ -102,6 +102,8 @@ export class Long {
    * @param unsigned - Whether unsigned or not, defaults to signed
    */
   constructor(low = 0, high = 0, unsigned?: boolean) {
+    if (!(this instanceof Long)) return new Long(low, high, unsigned);
+
     this.low = low | 0;
     this.high = high | 0;
     this.unsigned = !!unsigned;

src/max_key.ts

@@ -10,6 +10,10 @@ export interface MaxKeyExtended {
 export class MaxKey {
   _bsontype!: 'MaxKey';
 
+  constructor() {
+    if (!(this instanceof MaxKey)) return new MaxKey();
+  }
+
   /** @internal */
   toExtendedJSON(): MaxKeyExtended {
     return { $maxKey: 1 };