pkuczynski · Apr 10, 2026 · Apr 10, 2026 · Apr 10, 2026 · Apr 10, 2026 · Apr 10, 2026
diff --git a/eslint.config.mjs b/eslint.config.mjs
@@ -37,6 +37,7 @@ export default defineConfig([
             // custom rules
             "@typescript-eslint/consistent-type-exports": "error",
             "@typescript-eslint/consistent-type-imports": "error",
+            "@typescript-eslint/prefer-nullish-coalescing": "error",
             "@typescript-eslint/prefer-optional-chain": "error",
 
             // exceptions from typescript-eslint/recommended

diff --git a/sample/sample10-mixed/app.ts b/sample/sample10-mixed/app.ts
@@ -51,6 +51,6 @@ dataSource
         postRepository
             .save(post)
             .then((result) => console.log(result))
-            .catch((error) => console.log(error.stack ? error.stack : error))
+            .catch((error) => console.log(error.stack ?? error))
     })
-    .catch((error) => console.log(error.stack ? error.stack : error))
+    .catch((error) => console.log(error.stack ?? error))
diff --git a/sample/sample13-everywhere-abstraction/app.ts b/sample/sample13-everywhere-abstraction/app.ts
@@ -77,12 +77,8 @@ dataSource.initialize().then(
                 return blogRepository.save(blog)
             })
             .catch((error) =>
-                console.log(
-                    "Cannot save. Error: ",
-                    error.stack ? error.stack : error,
-                ),
+                console.log("Cannot save. Error: ", error.stack ?? error),
             )
     },
-    (error) =>
-        console.log("Cannot connect: ", error.stack ? error.stack : error),
+    (error) => console.log("Cannot connect: ", error.stack ?? error),
 )
diff --git a/sample/sample24-schemas/app.ts b/sample/sample24-schemas/app.ts
@@ -9,24 +9,24 @@
 // NOTE: this example is not working yet, only concepts of how this feature must work described here

 const PostEntity = new EntitySchema<Post>(
    require(
        __dirname + "/../../../../sample/sample24-schemas/schemas/post.json",
    ),
 )
 const PostDetailsEntity = new EntitySchema<PostDetails>(
    require(
        __dirname +
            "/../../../../sample/sample24-schemas/schemas/post-details.json",
    ),
 )
 const CategoryEntity = new EntitySchema<Category>(
    require(
        __dirname +
            "/../../../../sample/sample24-schemas/schemas/category.json",
    ),
 )
 const ImageEntity = new EntitySchema<Image>(
    require(
        __dirname + "/../../../../sample/sample24-schemas/schemas/image.json",
    ),
 )
@@ -66,6 +66,6 @@
             .then((result) => {
                 console.log(result)
             })
-            .catch((error) => console.log(error.stack ? error.stack : error))
+            .catch((error) => console.log(error.stack ?? error))
     })
-    .catch((error) => console.log(error.stack ? error.stack : error))
+    .catch((error) => console.log(error.stack ?? error))
diff --git a/sample/sample5-subscribers/app.ts b/sample/sample5-subscribers/app.ts
@@ -72,12 +72,8 @@ dataSource.initialize().then(
                 console.log("post removed.")
             })
             .catch((error) =>
-                console.log(
-                    "Cannot save. Error: ",
-                    error.stack ? error.stack : error,
-                ),
+                console.log("Cannot save. Error: ", error.stack ?? error),
             )
     },
-    (error) =>
-        console.log("Cannot connect: ", error.stack ? error.stack : error),
+    (error) => console.log("Cannot connect: ", error.stack ?? error),
 )
diff --git a/sample/sample6-abstract-table/app.ts b/sample/sample6-abstract-table/app.ts
@@ -72,12 +72,8 @@ dataSource.initialize().then(
                 return blogRepository.save(blog)
             })
             .catch((error) =>
-                console.log(
-                    "Cannot save. Error: ",
-                    error.stack ? error.stack : error,
-                ),
+                console.log("Cannot save. Error: ", error.stack ?? error),
             )
     },
-    (error) =>
-        console.log("Cannot connect: ", error.stack ? error.stack : error),
+    (error) => console.log("Cannot connect: ", error.stack ?? error),
 )
diff --git a/sample/sample7-pagination/app.ts b/sample/sample7-pagination/app.ts
@@ -71,12 +71,8 @@ dataSource.initialize().then(
                 console.log("count: ", entitiesWithCount[1])
             })
             .catch((error) =>
-                console.log(
-                    "Cannot save. Error: ",
-                    error.stack ? error.stack : error,
-                ),
+                console.log("Cannot save. Error: ", error.stack ?? error),
             )
     },
-    (error) =>
-        console.log("Cannot connect: ", error.stack ? error.stack : error),
+    (error) => console.log("Cannot connect: ", error.stack ?? error),
 )
diff --git a/sample/sample8-self-referencing/app.ts b/sample/sample8-self-referencing/app.ts
@@ -35,12 +35,8 @@ dataSource.initialize().then(
                 console.log("saved category: ", savedCategory)
             })
             .catch((error) =>
-                console.log(
-                    "Cannot save. Error: ",
-                    error.stack ? error.stack : error,
-                ),
+                console.log("Cannot save. Error: ", error.stack ?? error),
             )
     },
-    (error) =>
-        console.log("Cannot connect: ", error.stack ? error.stack : error),
+    (error) => console.log("Cannot connect: ", error.stack ?? error),
 )
diff --git a/sample/sample9-entity-listeners/app.ts b/sample/sample9-entity-listeners/app.ts
@@ -71,12 +71,8 @@ dataSource.initialize().then(
                 console.log("post removed.")
             })
             .catch((error) =>
-                console.log(
-                    "Cannot save. Error: ",
-                    error.stack ? error.stack : error,
-                ),
+                console.log("Cannot save. Error: ", error.stack ?? error),
             )
     },
-    (error) =>
-        console.log("Cannot connect: ", error.stack ? error.stack : error),
+    (error) => console.log("Cannot connect: ", error.stack ?? error),
 )
diff --git a/src/cache/DbQueryResultCache.ts b/src/cache/DbQueryResultCache.ts
@@ -32,7 +32,9 @@ export class DbQueryResultCache implements QueryResultCache {
             typeof this.dataSource.options.cache === "object"
                 ? this.dataSource.options.cache
                 : {}
-        const cacheTableName = cacheOptions.tableName || "query-result-cache"
+        const tableName =
+            cacheOptions.tableName === "" ? undefined : cacheOptions.tableName
+        const cacheTableName = tableName ?? "query-result-cache"
 
         this.queryResultCacheDatabase = database
         this.queryResultCacheSchema = schema
@@ -317,7 +319,7 @@ export class DbQueryResultCache implements QueryResultCache {
         identifiers: string[],
         queryRunner?: QueryRunner,
     ): Promise<void> {
-        const _queryRunner: QueryRunner = queryRunner || this.getQueryRunner()
+        const _queryRunner: QueryRunner = queryRunner ?? this.getQueryRunner()
         await Promise.all(
             identifiers.map((identifier) => {
                 const qb = _queryRunner.manager.createQueryBuilder()

diff --git a/src/cache/RedisQueryResultCache.ts b/src/cache/RedisQueryResultCache.ts
@@ -125,7 +125,9 @@ export class RedisQueryResultCache implements QueryResultCache {
         options: QueryResultCacheOptions,
         queryRunner?: QueryRunner,
     ): Promise<QueryResultCacheOptions | undefined> {
-        const key = options.identifier || options.query
+        const identifier =
+            options.identifier === "" ? undefined : options.identifier
+        const key = identifier ?? options.query
         if (!key) return undefined
 
         const result = await this.client.get(key)
@@ -153,7 +155,9 @@ export class RedisQueryResultCache implements QueryResultCache {
         savedCache: QueryResultCacheOptions,
         queryRunner?: QueryRunner,
     ): Promise<void> {
-        const key = options.identifier || options.query
+        const identifier =
+            options.identifier === "" ? undefined : options.identifier
+        const key = identifier ?? options.query
         if (!key) return
 
         const value = JSON.stringify(options)

diff --git a/src/cli-ts-node-esm.ts b/src/cli-ts-node-esm.ts
@@ -1,7 +1,7 @@
 #!/usr/bin/env node
 import { spawnSync } from "child_process"
 
-if ((process.env["NODE_OPTIONS"] || "").includes("--loader ts-node"))
+if ((process.env["NODE_OPTIONS"] ?? "").includes("--loader ts-node"))
     require("./cli")
 else {
     const childProcess = spawnSync(process.argv[0], process.argv.slice(1), {
@@ -19,5 +19,5 @@ else {
         windowsHide: true,
     })
 
-    process.exit(childProcess.status || 0)
+    process.exit(childProcess.status ?? 0)
 }
diff --git a/src/commands/InitCommand.ts b/src/commands/InitCommand.ts
@@ -62,7 +62,7 @@ export class InitCommand implements yargs.CommandModule {
 
     async handler(args: yargs.Arguments) {
         try {
-            const database: string = (args.database as any) || "postgres"
+            const database: string = (args.database as any) ?? "postgres"
             const isExpress = args.express !== undefined ? true : false
             const isDocker = args.docker !== undefined ? true : false
             const basePath = process.cwd() + (args.name ? "/" + args.name : "")
@@ -581,7 +581,7 @@ AppDataSource.initialize().then(async () => {
     ): string {
         return JSON.stringify(
             {
-                name: projectName || "typeorm-sample",
+                name: projectName ?? "typeorm-sample",
                 version: "0.0.1",
                 description: "Awesome project developed with TypeORM.",
                 type: projectIsEsm ? "module" : "commonjs",
@@ -741,15 +741,15 @@ Steps to run this project:
             ),
         )
 
-        if (!packageJson.devDependencies) packageJson.devDependencies = {}
+        packageJson.devDependencies ??= {}
         packageJson.devDependencies = {
             "@types/node": ourPackageJson.devDependencies["@types/node"],
             "ts-node": ourPackageJson.devDependencies["ts-node"],
             typescript: ourPackageJson.devDependencies.typescript,
             ...packageJson.devDependencies,
         }
 
-        if (!packageJson.dependencies) packageJson.dependencies = {}
+        packageJson.dependencies ??= {}
         packageJson.dependencies = {
             ...packageJson.dependencies,
             "reflect-metadata": ourPackageJson.dependencies["reflect-metadata"],
@@ -794,7 +794,7 @@ Steps to run this project:
             packageJson.dependencies["body-parser"] = "^1.20.3"
         }
 
-        if (!packageJson.scripts) packageJson.scripts = {}
+        packageJson.scripts ??= {}
 
         if (projectIsEsm)
             Object.assign(packageJson.scripts, {

diff --git a/src/connection/ConnectionOptionsReader.ts b/src/connection/ConnectionOptionsReader.ts
@@ -72,7 +72,7 @@ export class ConnectionOptionsReader {
 
         // try to find any of following configuration formats
         const foundFileFormat =
-            fileExtension ||
+            fileExtension ??
             fileFormats.find((format) => {
                 return PlatformTools.fileExist(this.baseFilePath + "." + format)
             })

diff --git a/src/data-source/DataSource.ts b/src/data-source/DataSource.ts
@@ -141,8 +141,8 @@ export class DataSource {
         this.driver = new DriverFactory().create(this)
         this.manager = this.createEntityManager()
         this.namingStrategy =
-            options.namingStrategy || new DefaultNamingStrategy()
-        this.metadataTableName = options.metadataTableName || "typeorm_metadata"
+            options.namingStrategy ?? new DefaultNamingStrategy()
+        this.metadataTableName = options.metadataTableName ?? "typeorm_metadata"
         this.queryResultCache = options.cache
             ? new QueryResultCacheFactory(this).create()
             : undefined
@@ -201,8 +201,8 @@ export class DataSource {
 
         if (options.logger || options.logging) {
             this.logger = new LoggerFactory().create(
-                options.logger || this.options.logger,
-                options.logging || this.options.logging,
+                options.logger ?? this.options.logger,
+                options.logging ?? this.options.logging,
             )
         }
 
@@ -361,10 +361,10 @@ export class DataSource {
 
         const migrationExecutor = new MigrationExecutor(this)
         migrationExecutor.transaction =
-            options?.transaction ||
-            this.options?.migrationsTransactionMode ||
+            options?.transaction ??
+            this.options?.migrationsTransactionMode ??
             "all"
-        migrationExecutor.fake = options?.fake || false
+        migrationExecutor.fake = options?.fake ?? false
 
         const successMigrations =
             await migrationExecutor.executePendingMigrations()
@@ -386,8 +386,8 @@ export class DataSource {
         if (!this.isInitialized) throw new CannotExecuteNotConnectedError()
 
         const migrationExecutor = new MigrationExecutor(this)
-        migrationExecutor.transaction = options?.transaction || "all"
-        migrationExecutor.fake = options?.fake || false
+        migrationExecutor.transaction = options?.transaction ?? "all"
+        migrationExecutor.fake = options?.fake ?? false
 
         await migrationExecutor.undoLastMigration()
     }
@@ -508,7 +508,7 @@ export class DataSource {
         if (queryRunner?.isReleased)
             throw new QueryRunnerProviderAlreadyReleasedError()
 
-        const usedQueryRunner = queryRunner || this.createQueryRunner()
+        const usedQueryRunner = queryRunner ?? this.createQueryRunner()
 
         try {
             return await usedQueryRunner.query(query, parameters) // await is needed here because we are using finally
@@ -710,7 +710,7 @@ export class DataSource {
 
         // create subscribers instances if they are not disallowed from high-level (for example they can disallowed from migrations run process)
         const flattenedSubscribers = ObjectUtils.mixedListToArray(
-            this.options.subscribers || [],
+            this.options.subscribers ?? [],
         )
         const subscribers =
             await connectionMetadataBuilder.buildSubscribers(
@@ -720,7 +720,7 @@ export class DataSource {
 
         // build entity metadatas
         const flattenedEntities = ObjectUtils.mixedListToArray(
-            this.options.entities || [],
+            this.options.entities ?? [],
         )
         const entityMetadatas =
             await connectionMetadataBuilder.buildEntityMetadatas(
@@ -735,7 +735,7 @@ export class DataSource {
 
         // create migration instances
         const flattenedMigrations = ObjectUtils.mixedListToArray(
-            this.options.migrations || [],
+            this.options.migrations ?? [],
         )
         const migrations =
             await connectionMetadataBuilder.buildMigrations(flattenedMigrations)

diff --git a/src/decorator/Check.ts b/src/decorator/Check.ts
@@ -37,7 +37,7 @@ export function Check(
     maybeExpression?: string,
 ): ClassDecorator & PropertyDecorator {
     const name = maybeExpression ? nameOrExpression : undefined
-    const expression = maybeExpression ? maybeExpression : nameOrExpression
+    const expression = maybeExpression ?? nameOrExpression
 
     if (!expression) throw new TypeORMError(`Check expression is required`)
 

diff --git a/src/decorator/Index.ts b/src/decorator/Index.ts
@@ -136,12 +136,11 @@ export function Index(
         !Array.isArray(nameOrFieldsOrOptions)
             ? (nameOrFieldsOrOptions as IndexOptions)
             : maybeOptions
-    if (!options)
-        options =
-            ObjectUtils.isObject(maybeFieldsOrOptions) &&
-            !Array.isArray(maybeFieldsOrOptions)
-                ? (maybeFieldsOrOptions as IndexOptions)
-                : maybeOptions
+    options ??=
+        ObjectUtils.isObject(maybeFieldsOrOptions) &&
+        !Array.isArray(maybeFieldsOrOptions)
+            ? (maybeFieldsOrOptions as IndexOptions)
+            : maybeOptions
 
     return function (
         clsOrObject: Function | Object,

diff --git a/src/decorator/Unique.ts b/src/decorator/Unique.ts
@@ -86,12 +86,11 @@ export function Unique(
         !Array.isArray(nameOrFieldsOrOptions)
             ? (nameOrFieldsOrOptions as UniqueOptions)
             : maybeOptions
-    if (!options)
-        options =
-            ObjectUtils.isObject(nameOrFieldsOrOptions) &&
-            !Array.isArray(maybeFieldsOrOptions)
-                ? (maybeFieldsOrOptions as UniqueOptions)
-                : maybeOptions
+    options ??=
+        ObjectUtils.isObject(nameOrFieldsOrOptions) &&
+        !Array.isArray(maybeFieldsOrOptions)
+            ? (maybeFieldsOrOptions as UniqueOptions)
+            : maybeOptions
 
     return function (
         clsOrObject: Function | Object,

diff --git a/src/decorator/columns/Column.ts b/src/decorator/columns/Column.ts
@@ -185,7 +185,7 @@ export function Column(
             options = <ColumnOptions>typeOrOptions
             type = typeOrOptions.type
         }
-        if (!options) options = {} as ColumnOptions
+        options ??= {} as ColumnOptions
 
         // if type is not given explicitly then try to guess it
         const reflectMetadataType =
@@ -215,8 +215,7 @@ export function Column(
                 propertyName: propertyName,
                 isArray:
                     reflectMetadataType === Array || options.array === true,
-                prefix:
-                    options.prefix !== undefined ? options.prefix : undefined,
+                prefix: options.prefix ?? undefined,
                 type: typeOrOptions as (type?: any) => Function,
             } as EmbeddedMetadataArgs)
         } else {

diff --git a/src/decorator/columns/CreateDateColumn.ts b/src/decorator/columns/CreateDateColumn.ts
@@ -15,7 +15,7 @@ export function CreateDateColumn(options?: ColumnOptions): PropertyDecorator {
             target: object.constructor,
             propertyName: propertyName,
             mode: "createDate",
-            options: options || {},
+            options: options ?? {},
         } as ColumnMetadataArgs)
     }
 }
diff --git a/src/decorator/columns/DeleteDateColumn.ts b/src/decorator/columns/DeleteDateColumn.ts
@@ -14,7 +14,7 @@ export function DeleteDateColumn(options?: ColumnOptions): PropertyDecorator {
             target: object.constructor,
             propertyName: propertyName,
             mode: "deleteDate",
-            options: options || {},
+            options: options ?? {},
         } as ColumnMetadataArgs)
     }
 }