fix: Decorators should implement the official TypeScript interface

Closes: #5922

Author: Sahin Vardar

src/decorator/Check.ts

@@ -6,29 +6,29 @@ import {CheckMetadataArgs} from "../metadata-args/CheckMetadataArgs";
  * Can be used on entity property or on entity.
  * Can create checks with composite columns when used on entity.
  */
-export function Check(expression: string): Function;
+export function Check(expression: string): ClassDecorator & PropertyDecorator;
 
 /**
  * Creates a database check.
  * Can be used on entity property or on entity.
  * Can create checks with composite columns when used on entity.
  */
-export function Check(name: string, expression: string): Function;
+export function Check(name: string, expression: string): ClassDecorator & PropertyDecorator;
 
 /**
  * Creates a database check.
  * Can be used on entity property or on entity.
  * Can create checks with composite columns when used on entity.
  */
-export function Check(nameOrExpression: string, maybeExpression?: string): Function {
+export function Check(nameOrExpression: string, maybeExpression?: string): ClassDecorator & PropertyDecorator {
 
     const name = maybeExpression ? nameOrExpression : undefined;
     const expression = maybeExpression ? maybeExpression : nameOrExpression;
 
     if (!expression)
         throw new Error(`Check expression is required`);
 
-    return function (clsOrObject: Function|Object, propertyName?: string) {
+    return function (clsOrObject: Function|Object, propertyName?: string | symbol) {
 
         getMetadataArgsStorage().checks.push({
             target: propertyName ? clsOrObject.constructor : clsOrObject as Function,

src/decorator/EntityRepository.ts

@@ -7,7 +7,7 @@ import { EntitySchema } from "../entity-schema/EntitySchema";
  * Custom repository can manage some specific entity or just be generic.
  * Custom repository optionally can extend AbstractRepository, Repository or TreeRepository.
  */
-export function EntityRepository(entity?: Function | EntitySchema<any>): Function {
+export function EntityRepository(entity?: Function | EntitySchema<any>): ClassDecorator {
     return function (target: Function) {
 
         getMetadataArgsStorage().entityRepositories.push({

src/decorator/Exclusion.ts

@@ -6,29 +6,29 @@ import {ExclusionMetadataArgs} from "../metadata-args/ExclusionMetadataArgs";
  * Can be used on entity.
  * Can create exclusions with composite columns when used on entity.
  */
-export function Exclusion(expression: string): Function;
+export function Exclusion(expression: string): ClassDecorator & PropertyDecorator;
 
 /**
  * Creates a database exclusion.
  * Can be used on entity.
  * Can create exclusions with composite columns when used on entity.
  */
-export function Exclusion(name: string, expression: string): Function;
+export function Exclusion(name: string, expression: string): ClassDecorator & PropertyDecorator;
 
 /**
  * Creates a database exclusion.
  * Can be used on entity.
  * Can create exclusions with composite columns when used on entity.
  */
-export function Exclusion(nameOrExpression: string, maybeExpression?: string): Function {
+export function Exclusion(nameOrExpression: string, maybeExpression?: string): ClassDecorator & PropertyDecorator {
 
     const name = maybeExpression ? nameOrExpression : undefined;
     const expression = maybeExpression ? maybeExpression : nameOrExpression;
 
     if (!expression)
         throw new Error(`Exclusion expression is required`);
 
-    return function (clsOrObject: Function|Object, propertyName?: string) {
+    return function (clsOrObject: Function|Object, propertyName?: string | symbol) {
 
         getMetadataArgsStorage().exclusions.push({
             target: propertyName ? clsOrObject.constructor : clsOrObject as Function,

src/decorator/Generated.ts

@@ -10,7 +10,7 @@ import {GeneratedMetadataArgs} from "../metadata-args/GeneratedMetadataArgs";
  *
  * Note, some databases do not support non-primary generation columns.
  */
-export function Generated(strategy: "increment"|"uuid"|"rowid" = "increment"): Function {
+export function Generated(strategy: "increment"|"uuid"|"rowid" = "increment"): PropertyDecorator {
     return function (object: Object, propertyName: string) {
 
         getMetadataArgsStorage().generations.push({

src/decorator/Index.ts

@@ -6,49 +6,49 @@ import {IndexMetadataArgs} from "../metadata-args/IndexMetadataArgs";
  * Can be used on entity property or on entity.
  * Can create indices with composite columns when used on entity.
  */
-export function Index(options?: IndexOptions): Function;
+export function Index(options?: IndexOptions): ClassDecorator & PropertyDecorator;
 
 /**
  * Creates a database index.
  * Can be used on entity property or on entity.
  * Can create indices with composite columns when used on entity.
  */
-export function Index(name: string, options?: IndexOptions): Function;
+export function Index(name: string, options?: IndexOptions): ClassDecorator & PropertyDecorator;
 
 /**
  * Creates a database index.
  * Can be used on entity property or on entity.
  * Can create indices with composite columns when used on entity.
  */
-export function Index(name: string, options: { synchronize: false }): Function;
+export function Index(name: string, options: { synchronize: false }): ClassDecorator & PropertyDecorator;
 
 /**
  * Creates a database index.
  * Can be used on entity property or on entity.
  * Can create indices with composite columns when used on entity.
  */
-export function Index(name: string, fields: string[], options?: IndexOptions): Function;
+export function Index(name: string, fields: string[], options?: IndexOptions): ClassDecorator & PropertyDecorator;
 
 /**
  * Creates a database index.
  * Can be used on entity property or on entity.
  * Can create indices with composite columns when used on entity.
  */
-export function Index(fields: string[], options?: IndexOptions): Function;
+export function Index(fields: string[], options?: IndexOptions): ClassDecorator & PropertyDecorator;
 
 /**
  * Creates a database index.
  * Can be used on entity property or on entity.
  * Can create indices with composite columns when used on entity.
  */
-export function Index(fields: (object?: any) => (any[]|{ [key: string]: number }), options?: IndexOptions): Function;
+export function Index(fields: (object?: any) => (any[]|{ [key: string]: number }), options?: IndexOptions): ClassDecorator & PropertyDecorator;
 
 /**
  * Creates a database index.
  * Can be used on entity property or on entity.
  * Can create indices with composite columns when used on entity.
  */
-export function Index(name: string, fields: (object?: any) => (any[]|{ [key: string]: number }), options?: IndexOptions): Function;
+export function Index(name: string, fields: (object?: any) => (any[]|{ [key: string]: number }), options?: IndexOptions): ClassDecorator & PropertyDecorator;
 
 /**
  * Creates a database index.
@@ -57,7 +57,7 @@ export function Index(name: string, fields: (object?: any) => (any[]|{ [key: str
  */
 export function Index(nameOrFieldsOrOptions?: string|string[]|((object: any) => (any[]|{ [key: string]: number }))|IndexOptions,
                       maybeFieldsOrOptions?: ((object?: any) => (any[]|{ [key: string]: number }))|IndexOptions|string[]|{ synchronize: false },
-                      maybeOptions?: IndexOptions): Function {
+                      maybeOptions?: IndexOptions): ClassDecorator & PropertyDecorator {
 
     // normalize parameters
     const name = typeof nameOrFieldsOrOptions === "string" ? nameOrFieldsOrOptions : undefined;
@@ -66,7 +66,7 @@ export function Index(nameOrFieldsOrOptions?: string|string[]|((object: any) =>
     if (!options)
         options = (typeof maybeFieldsOrOptions === "object" && !Array.isArray(maybeFieldsOrOptions)) ? maybeFieldsOrOptions as IndexOptions : maybeOptions;
 
-    return function (clsOrObject: Function|Object, propertyName?: string) {
+    return function (clsOrObject: Function|Object, propertyName?: string | symbol) {
 
         getMetadataArgsStorage().indices.push({
             target: propertyName ? clsOrObject.constructor : clsOrObject as Function,

src/decorator/Unique.ts

@@ -1,39 +1,54 @@
-import {getMetadataArgsStorage} from "../index";
-import {UniqueMetadataArgs} from "../metadata-args/UniqueMetadataArgs";
+import { getMetadataArgsStorage } from "../index";
+import { UniqueMetadataArgs } from "../metadata-args/UniqueMetadataArgs";
 
 /**
  * Composite unique constraint must be set on entity classes and must specify entity's fields to be unique.
  */
-export function Unique(name: string, fields: string[]): Function;
+export function Unique(name: string, fields: string[]): ClassDecorator & PropertyDecorator;
 
 /**
  * Composite unique constraint must be set on entity classes and must specify entity's fields to be unique.
  */
-export function Unique(fields: string[]): Function;
+export function Unique(fields: string[]): ClassDecorator & PropertyDecorator;
 
 /**
  * Composite unique constraint must be set on entity classes and must specify entity's fields to be unique.
  */
-export function Unique(fields: (object?: any) => (any[]|{ [key: string]: number })): Function;
+export function Unique(fields: (object?: any) => (any[] | { [key: string]: number })): ClassDecorator & PropertyDecorator;
 
 /**
  * Composite unique constraint must be set on entity classes and must specify entity's fields to be unique.
  */
-export function Unique(name: string, fields: (object?: any) => (any[]|{ [key: string]: number })): Function;
+export function Unique(name: string, fields: (object?: any) => (any[] | { [key: string]: number })): ClassDecorator & PropertyDecorator;
 
 /**
  * Composite unique constraint must be set on entity classes and must specify entity's fields to be unique.
  */
-export function Unique(nameOrFields?: string|string[]|((object: any) => (any[]|{ [key: string]: number })),
-                       maybeFields?: ((object?: any) => (any[]|{ [key: string]: number }))|string[]): Function {
+export function Unique(nameOrFields?: string | string[] | ((object: any) => (any[] | { [key: string]: number })),
+    maybeFields?: ((object?: any) => (any[] | { [key: string]: number })) | string[]): ClassDecorator & PropertyDecorator {
     const name = typeof nameOrFields === "string" ? nameOrFields : undefined;
-    const fields = typeof nameOrFields === "string" ? <((object?: any) => (any[]|{ [key: string]: number }))|string[]> maybeFields : nameOrFields as string[];
+    const fields = typeof nameOrFields === "string" ? <((object?: any) => (any[] | { [key: string]: number })) | string[]>maybeFields : nameOrFields as string[];
+
+    return function (clsOrObject: Function | Object, propertyName?: string | symbol) {
+
+        let columns = fields;
+
+        if (propertyName !== undefined) {
+            switch (typeof (propertyName)) {
+                case 'string':
+                    columns = [propertyName];
+                    break;
+
+                case 'symbol':
+                    columns= [propertyName.toString()];
+                    break;
+            }
+        }
 
-    return function (clsOrObject: Function|Object, propertyName?: string) {
         const args: UniqueMetadataArgs = {
             target: propertyName ? clsOrObject.constructor : clsOrObject as Function,
             name: name,
-            columns: propertyName ? [propertyName] : fields
+            columns,
         };
         getMetadataArgsStorage().uniques.push(args);
     };

src/decorator/columns/Column.ts

@@ -20,67 +20,67 @@ import { GeneratedMetadataArgs } from "../../metadata-args/GeneratedMetadataArgs
  * Column decorator is used to mark a specific class property as a table column. Only properties decorated with this
  * decorator will be persisted to the database when entity be saved.
  */
-export function Column(): Function;
+export function Column(): PropertyDecorator;
 
 /**
  * Column decorator is used to mark a specific class property as a table column.
  * Only properties decorated with this decorator will be persisted to the database when entity be saved.
  */
-export function Column(options: ColumnOptions): Function;
+export function Column(options: ColumnOptions): PropertyDecorator;
 
 /**
  * Column decorator is used to mark a specific class property as a table column.
  * Only properties decorated with this decorator will be persisted to the database when entity be saved.
  */
-export function Column(type: SimpleColumnType, options?: ColumnCommonOptions): Function;
+export function Column(type: SimpleColumnType, options?: ColumnCommonOptions): PropertyDecorator;
 
 /**
  * Column decorator is used to mark a specific class property as a table column.
  * Only properties decorated with this decorator will be persisted to the database when entity be saved.
  */
-export function Column(type: SpatialColumnType, options?: ColumnCommonOptions & SpatialColumnOptions): Function;
+export function Column(type: SpatialColumnType, options?: ColumnCommonOptions & SpatialColumnOptions): PropertyDecorator;
 
 /**
  * Column decorator is used to mark a specific class property as a table column.
  * Only properties decorated with this decorator will be persisted to the database when entity be saved.
  */
-export function Column(type: WithLengthColumnType, options?: ColumnCommonOptions & ColumnWithLengthOptions): Function;
+export function Column(type: WithLengthColumnType, options?: ColumnCommonOptions & ColumnWithLengthOptions): PropertyDecorator;
 
 /**
  * Column decorator is used to mark a specific class property as a table column.
  * Only properties decorated with this decorator will be persisted to the database when entity be saved.
  */
-export function Column(type: WithWidthColumnType, options?: ColumnCommonOptions & ColumnWithWidthOptions): Function;
+export function Column(type: WithWidthColumnType, options?: ColumnCommonOptions & ColumnWithWidthOptions): PropertyDecorator;
 
 /**
  * Column decorator is used to mark a specific class property as a table column.
  * Only properties decorated with this decorator will be persisted to the database when entity be saved.
  */
-export function Column(type: WithPrecisionColumnType, options?: ColumnCommonOptions & ColumnNumericOptions): Function;
+export function Column(type: WithPrecisionColumnType, options?: ColumnCommonOptions & ColumnNumericOptions): PropertyDecorator;
 
 /**
  * Column decorator is used to mark a specific class property as a table column.
  * Only properties decorated with this decorator will be persisted to the database when entity be saved.
  */
-export function Column(type: "enum", options?: ColumnCommonOptions & ColumnEnumOptions): Function;
+export function Column(type: "enum", options?: ColumnCommonOptions & ColumnEnumOptions): PropertyDecorator;
 
 /**
  * Column decorator is used to mark a specific class property as a table column.
  * Only properties decorated with this decorator will be persisted to the database when entity be saved.
  */
-export function Column(type: "simple-enum", options?: ColumnCommonOptions & ColumnEnumOptions): Function;
+export function Column(type: "simple-enum", options?: ColumnCommonOptions & ColumnEnumOptions): PropertyDecorator;
 
 /**
  * Column decorator is used to mark a specific class property as a table column.
  * Only properties decorated with this decorator will be persisted to the database when entity be saved.
  */
-export function Column(type: "set", options?: ColumnCommonOptions & ColumnEnumOptions): Function;
+export function Column(type: "set", options?: ColumnCommonOptions & ColumnEnumOptions): PropertyDecorator;
 
 /**
  * Column decorator is used to mark a specific class property as a table column.
  * Only properties decorated with this decorator will be persisted to the database when entity be saved.
  */
-export function Column(type: "hstore", options?: ColumnCommonOptions & ColumnHstoreOptions): Function;
+export function Column(type: "hstore", options?: ColumnCommonOptions & ColumnHstoreOptions): PropertyDecorator;
 
 /**
  * Column decorator is used to mark a specific class property as a table column.
@@ -90,13 +90,13 @@ export function Column(type: "hstore", options?: ColumnCommonOptions & ColumnHst
  * single table of the entity where Embedded is used. And on hydration all columns which supposed to be in the
  * embedded will be mapped to it from the single table.
  */
-export function Column(type: (type?: any) => Function, options?: ColumnEmbeddedOptions): Function;
+export function Column(type: (type?: any) => Function, options?: ColumnEmbeddedOptions): PropertyDecorator;
 
 /**
  * Column decorator is used to mark a specific class property as a table column.
  * Only properties decorated with this decorator will be persisted to the database when entity be saved.
  */
-export function Column(typeOrOptions?: ((type?: any) => Function)|ColumnType|(ColumnOptions&ColumnEmbeddedOptions), options?: (ColumnOptions&ColumnEmbeddedOptions)): Function {
+export function Column(typeOrOptions?: ((type?: any) => Function)|ColumnType|(ColumnOptions&ColumnEmbeddedOptions), options?: (ColumnOptions&ColumnEmbeddedOptions)): PropertyDecorator {
     return function (object: Object, propertyName: string) {
 
         // normalize parameters

src/decorator/columns/CreateDateColumn.ts

@@ -6,7 +6,7 @@ import {ColumnMetadataArgs} from "../../metadata-args/ColumnMetadataArgs";
  * Creation date is generated and inserted only once,
  * at the first time when you create an object, the value is inserted into the table, and is never touched again.
  */
-export function CreateDateColumn(options?: ColumnOptions): Function {
+export function CreateDateColumn(options?: ColumnOptions): PropertyDecorator {
     return function (object: Object, propertyName: string) {
         getMetadataArgsStorage().columns.push({
             target: object.constructor,

src/decorator/columns/DeleteDateColumn.ts

@@ -5,7 +5,7 @@ import { ColumnMetadataArgs } from "../../metadata-args/ColumnMetadataArgs";
  * This column will store a delete date of the soft-deleted object.
  * This date is being updated each time you soft-delete the object.
  */
-export function DeleteDateColumn(options?: ColumnOptions): Function {
+export function DeleteDateColumn(options?: ColumnOptions): PropertyDecorator {
     return function(object: Object, propertyName: string) {
         getMetadataArgsStorage().columns.push({
             target: object.constructor,

src/decorator/columns/ObjectIdColumn.ts

@@ -5,7 +5,7 @@ import {ColumnMetadataArgs} from "../../metadata-args/ColumnMetadataArgs";
  * Special type of column that is available only for MongoDB database.
  * Marks your entity's column to be an object id.
  */
-export function ObjectIdColumn(options?: ColumnOptions): Function {
+export function ObjectIdColumn(options?: ColumnOptions): PropertyDecorator {
     return function (object: Object, propertyName: string) {
 
         // if column options are not given then create a new empty options