diff --git a/knip.ts b/knip.ts
index 25de69c9596b..f3ba79ad6c30 100644
--- a/knip.ts
+++ b/knip.ts
@@ -58,6 +58,9 @@ export default {
     'packages/parser': {
       ignore: ['tests/fixtures/**'],
     },
+    'packages/rule-tester': {
+      ignore: ['tests/fixtures/**'],
+    },
     'packages/scope-manager': {
       ignore: ['tests/fixtures/**'],
     },
diff --git a/packages/eslint-plugin/tests/fixtures/file.tsx b/packages/eslint-plugin/tests/fixtures/file.tsx
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/packages/rule-tester/package.json b/packages/rule-tester/package.json
index 197bad98254c..86d293d1c82e 100644
--- a/packages/rule-tester/package.json
+++ b/packages/rule-tester/package.json
@@ -52,6 +52,7 @@
     "@typescript-eslint/utils": "7.13.0",
     "ajv": "^6.12.6",
     "json-stable-stringify-without-jsonify": "^1.0.1",
+    "lodash": "^4.6.2",
     "lodash.merge": "4.6.2",
     "semver": "^7.6.0"
   },
diff --git a/packages/rule-tester/src/FlatRuleTester.ts b/packages/rule-tester/src/FlatRuleTester.ts
new file mode 100644
index 000000000000..005ce00f5a3f
--- /dev/null
+++ b/packages/rule-tester/src/FlatRuleTester.ts
@@ -0,0 +1,612 @@
+import assert from 'node:assert';
+import { existsSync } from 'node:fs';
+import { join } from 'node:path';
+
+import { getParserServices } from '@typescript-eslint/utils/eslint-utils';
+import type {
+  FlatConfig,
+  LooseRuleDefinition,
+  RuleModule,
+} from '@typescript-eslint/utils/ts-eslint';
+import { Linter } from '@typescript-eslint/utils/ts-eslint';
+import { isEqual } from 'lodash';
+
+import { TestFramework } from './TestFramework';
+import type {
+  ExpectedError,
+  ExpectedSuggestion,
+  FileUnawareConfig,
+  InvalidSample,
+  LegacyInvalidSample,
+  LegacyValidSample,
+  RuleTesterConfig,
+  Sample,
+  ValidSample,
+} from './types/FlatRuleTester';
+import { interpolate } from './utils/interpolate';
+import * as SourceCodeFixer from './utils/SourceCodeFixer';
+import { sanitize } from './utils/validationHelpers';
+
+// Hide methods publicly by default, for simplicity's sake
+export const DATA = Symbol('DATA');
+export const CONSTRUCT = Symbol('CONSTRUCT');
+
+// Needed for type exports
+// eslint-disable-next-line @typescript-eslint/no-namespace
+export declare namespace FlatRuleTester {
+  export type {
+    ExpectedError,
+    ExpectedSuggestion,
+    InvalidSample,
+    LegacyInvalidSample,
+    LegacyValidSample,
+    RuleTesterConfig,
+    Sample,
+    ValidSample,
+    FileUnawareConfig,
+  };
+}
+
+/**
+ * The new, flat rule tester
+ *
+ * **WARNING:** This is NOT a drop-in-replacement for RuleTester, minor code migration will be needed and major code migration will be needed for optimal performance (See {@linkcode FlatRuleConfig#fromObject})
+ *
+ * List of current breaking changes:
+ * - Uses ESLint's flat config system
+ * - Requires type-checking
+ * - Does not support string imports for parsers
+ * - Does not support modifying parserOptions on a per-case basis (For performance reasons)
+ */
+export class FlatRuleTester<F extends string> extends TestFramework {
+  #config: Readonly<RuleTesterConfig<F>>;
+  #rules: FlatRuleConfig<string, unknown[]>[];
+  #linter: Linter;
+  #fixtureDir: string;
+  #hasTested: boolean;
+
+  constructor(readonly config: Readonly<RuleTesterConfig<F>>) {
+    super();
+    this.#hasTested = false;
+    this.#config = config;
+    this.#rules = [];
+    this.#linter = new Linter({
+      // @ts-expect-error: Broken types
+      configType: 'flat',
+    });
+
+    this.#fixtureDir = this.#config.fixtureRootDir;
+    assert.ok(existsSync(this.#fixtureDir), 'Fixture directory must exist');
+  }
+
+  /**
+   * Defines a new rule
+   *
+   * It is up to the caller to ensure no rules are duplicated
+   */
+  rule<M extends string, O extends unknown[]>(
+    name: string,
+    rule: RuleModule<M, O>,
+  ): FlatRuleConfig<M, O> {
+    const tester = FlatRuleConfig[CONSTRUCT](name, rule);
+    this.#rules.push(tester);
+    return tester;
+  }
+
+  /**
+   * Run the defined tests.
+   *
+   * Must be called exactly once, after all tests have been defined.
+   *
+   * Explanation of why we need to do this below:
+   * ```md
+   * Some testing frameworks do not allow tests to be defined in the afterAll hook, this is a problem and prevents us from automatically running tests.
+   * Thus, for consistency, we always require the calling of the test() method
+   * ```
+   */
+  test(): void {
+    assert.ok(!this.#hasTested, 'You should only call the test() method once!');
+    this.#hasTested = true;
+
+    for (const ruleDef of this.#rules) {
+      const { rule, name, configurations } = ruleDef[DATA]();
+
+      FlatRuleTester.describe(name, () => {
+        configurations
+          .map(c => c[DATA]())
+          .forEach(data => {
+            const custom: FlatConfig.Config = {
+              languageOptions: {
+                parserOptions: {
+                  tsconfigRootDir: this.#fixtureDir,
+                  project: true,
+                },
+              },
+              plugins: {
+                assertions: {
+                  meta: {
+                    name: 'assertions',
+                  },
+                  rules: {
+                    assertions: {
+                      meta: {
+                        messages: {
+                          assert: 'assert',
+                        },
+                        schema: [],
+                        type: 'problem',
+                      },
+                      defaultOptions: [],
+                      // eslint-disable-next-line @typescript-eslint/explicit-function-return-type
+                      create(ctx) {
+                        assert.doesNotThrow(
+                          () => getParserServices(ctx),
+                          'Parser services must be available',
+                        );
+
+                        return {};
+                      },
+                    } satisfies RuleModule<'assert'> as LooseRuleDefinition,
+                  },
+                },
+                rule: {
+                  meta: {
+                    name: 'rule',
+                  },
+                  rules: {
+                    rule,
+                  },
+                },
+              },
+              rules: {
+                'rule/rule': ['error', ...data.configuration],
+                'assertions/assertions': ['error'],
+              },
+              files: ['**/*.*'],
+            };
+
+            FlatRuleTester.describe('valid', () =>
+              data.valid.forEach(validCase =>
+                FlatRuleTester.it(validCase.name, () => {
+                  const extension: F = (validCase.extension ??
+                    this.#config.defaultExtension ??
+                    'ts') as F;
+                  assert.ok(
+                    Object.prototype.hasOwnProperty.call(
+                      this.#config.extensions,
+                      extension,
+                    ),
+                    `Undefined format: ${sanitize(extension)}, should be in ${sanitize(Object.keys(this.#config.extensions).join(', '))}`,
+                  );
+
+                  const name = `/file.${extension}`;
+                  assert.ok(
+                    existsSync(join(this.#fixtureDir, name)),
+                    `Fixtures must exist for format: ${sanitize(name)}`,
+                  );
+
+                  const fullConfig: FlatConfig.ConfigArray = [
+                    custom,
+                    {
+                      ...this.#config.baseOptions,
+                      files: ['**/*.*'],
+                    },
+                  ];
+
+                  const formatConfig = this.#config.extensions[extension];
+
+                  assert.notStrictEqual(formatConfig, undefined);
+
+                  fullConfig.splice(1, 0, {
+                    ...formatConfig,
+                    files: [`**/*.${extension}`],
+                  });
+
+                  const results = this.#linter.verify(
+                    validCase.code,
+                    fullConfig,
+                    join(this.#fixtureDir, name),
+                  );
+
+                  results.forEach(msg => {
+                    throw new Error(
+                      `Got error ${sanitize(msg.message)} (${msg.messageId ? sanitize(msg.messageId) : '(unknown message ID)'}), expected nothing`,
+                    );
+                  });
+                }),
+              ),
+            );
+            FlatRuleTester.describe('invalid', () =>
+              data.invalid.forEach(invalidCase =>
+                FlatRuleTester.it(sanitize(invalidCase.name), () => {
+                  const extension: F = (invalidCase.extension ??
+                    this.#config.defaultExtension ??
+                    'ts') as F;
+                  assert.ok(
+                    Object.prototype.hasOwnProperty.call(
+                      this.#config.extensions,
+                      extension,
+                    ),
+                    `Undefined format: ${sanitize(extension)}, should be in ${sanitize(Object.keys(this.#config.extensions).join(', '))}`,
+                  );
+
+                  const name = `/file.${extension}`;
+                  assert.ok(
+                    existsSync(join(this.#fixtureDir, name)),
+                    'Fixtures must exist',
+                  );
+
+                  const fullConfig: FlatConfig.ConfigArray = [
+                    custom,
+                    {
+                      ...this.#config.baseOptions,
+                      files: ['**/*.*'],
+                    },
+                  ];
+                  const formatConfig = this.#config.extensions[extension];
+                  fullConfig.splice(1, 0, {
+                    ...formatConfig,
+                    files: [`**/*.${invalidCase.extension}`],
+                  });
+
+                  const allMessages: Linter.LintMessage[] = [];
+                  const results = this.#linter.verifyAndFix(
+                    invalidCase.code,
+                    fullConfig,
+                    {
+                      filename: join(this.#fixtureDir, name),
+                      fix: true,
+                      postprocess: messages => {
+                        const e = messages.reduce((prev, cur) => [
+                          ...prev,
+                          ...cur,
+                        ]);
+                        allMessages.push(...e);
+                        return e;
+                      },
+                    },
+                  );
+                  results.messages = allMessages; // ESLint bug ._. this fixes it
+
+                  if (typeof invalidCase.output === 'string') {
+                    assert.strictEqual(
+                      results.output,
+                      invalidCase.output,
+                      'Output code and fix differ',
+                    );
+                  } else {
+                    assert.strictEqual(
+                      results.output,
+                      invalidCase.code,
+                      'Result output must be untouched',
+                    );
+                  }
+
+                  assert.strictEqual(
+                    results.messages.length,
+                    invalidCase.errors.length,
+                    'Result messages must be the same length',
+                  );
+
+                  results.messages.forEach((message, idx) => {
+                    assert.ok(
+                      message.ruleId != null,
+                      `Parser/linter error occured: ${sanitize(message.message)}`,
+                    );
+
+                    assert.ok(
+                      message.ruleId === 'rule/rule',
+                      `Errors must be from the defined rule, as opposed to typescript-eslint or eslint: ${sanitize(message.ruleId)}`,
+                    );
+
+                    const expectedMessage = invalidCase.errors[idx];
+
+                    if (expectedMessage.column) {
+                      assert.strictEqual(
+                        expectedMessage.column,
+                        message.column,
+                        'Error column must be the same',
+                      );
+                    }
+                    if (expectedMessage.endColumn) {
+                      assert.strictEqual(
+                        expectedMessage.endColumn,
+                        message.endColumn,
+                        'Error end column must be the same',
+                      );
+                    }
+                    if (expectedMessage.line) {
+                      assert.strictEqual(
+                        expectedMessage.line,
+                        message.line,
+                        'Error line must be the same',
+                      );
+                    }
+                    if (expectedMessage.endLine) {
+                      assert.strictEqual(
+                        expectedMessage.endLine,
+                        message.endLine,
+                        'Error end line must be the same',
+                      );
+                    }
+                    if (expectedMessage.message) {
+                      assert.strictEqual(
+                        expectedMessage.message,
+                        message.message,
+                        'Error message must be the same',
+                      );
+                    }
+                    if (expectedMessage.messageId) {
+                      assert.strictEqual(
+                        expectedMessage.messageId,
+                        message.messageId,
+                        'Error message ID must be the same',
+                      );
+                    }
+                    if (expectedMessage.type) {
+                      assert.strictEqual(
+                        expectedMessage.type,
+                        message.nodeType,
+                        'Error message ID must be the same',
+                      );
+                    }
+
+                    // eslint-disable-next-line deprecation/deprecation
+                    if (expectedMessage.data) {
+                      this.#config;
+                      assert.ok(message.messageId !== undefined);
+
+                      const hydrated = interpolate(
+                        rule.meta.messages[message.messageId],
+                        // eslint-disable-next-line deprecation/deprecation
+                        expectedMessage.data as Record<string, unknown>,
+                      );
+
+                      assert.strictEqual(
+                        message.message,
+                        hydrated,
+                        'Message must be equal to data-hydrated message',
+                      );
+                    }
+
+                    if (expectedMessage.suggestions !== undefined) {
+                      assert.ok(
+                        message.suggestions !== undefined,
+                        'Suggestions must not be undefined',
+                      );
+
+                      assert.strictEqual(
+                        expectedMessage.suggestions.length,
+                        message.suggestions.length,
+                        'Result suggestions must be the same length',
+                      );
+                      message.suggestions.forEach((suggestion, idx) => {
+                        const expectedSuggestion =
+                          // @ts-expect-error: TS forgot that we did an assertion
+                          expectedMessage.suggestions[idx];
+
+                        if (expectedSuggestion.desc) {
+                          assert.strictEqual(
+                            expectedSuggestion.desc,
+                            suggestion.desc,
+                            'Suggestion description must be the same',
+                          );
+                        }
+                        if (expectedSuggestion.output) {
+                          assert.strictEqual(
+                            expectedSuggestion.output,
+                            SourceCodeFixer.applyFixes(results.output, [
+                              suggestion,
+                            ]).output,
+                            'Suggestion must be the same must be the same',
+                          );
+                        }
+                        if (expectedSuggestion.messageId) {
+                          assert.strictEqual(
+                            expectedSuggestion.messageId,
+                            suggestion.messageId,
+                            'Suggestion message ID must be the same',
+                          );
+                        }
+                      });
+                    }
+                  });
+                }),
+              ),
+            );
+          });
+      });
+
+      for (const [_, value] of Object.entries(
+        // No actual cast done, just removing the type argument
+        this.#config.extensions as RuleTesterConfig<string>['extensions'],
+      )) {
+        // eslint-disable-next-line @typescript-eslint/consistent-type-imports
+        type parser = typeof import('@typescript-eslint/parser');
+        if (
+          value.languageOptions?.parser &&
+          (value.languageOptions.parser as parser | { clearCaches: undefined })
+            .clearCaches
+        ) {
+          (value.languageOptions.parser as parser).clearCaches();
+        }
+      }
+    }
+  }
+}
+
+export class FlatRuleConfig<
+  MessageIds extends string,
+  Options extends unknown[],
+> {
+  #name: string;
+  #configurations: FlatRuleConfiguration<MessageIds, Options>[];
+  #rule: RuleModule<MessageIds, Options>;
+
+  #findOrMakeConfiguration(
+    configuration: Options,
+  ): FlatRuleConfiguration<MessageIds, Options> {
+    let found: FlatRuleConfiguration<MessageIds, Options> | undefined =
+      this.#configurations.find(val =>
+        isEqual(val[DATA]().configuration, configuration),
+      );
+    if (!found) {
+      found = new FlatRuleConfiguration(configuration);
+      this.#configurations.push(found);
+    }
+
+    return found;
+  }
+
+  private constructor(name: string, rule: RuleModule<MessageIds, Options>) {
+    this.#name = name;
+    this.#rule = rule;
+    this.#configurations = [];
+  }
+
+  /**
+   * Defines a new configuration
+   *
+   * Use this over fromObject
+   */
+  configuration(
+    ...configuration: Options
+  ): FlatRuleConfiguration<MessageIds, Options> {
+    const opt = new FlatRuleConfiguration<MessageIds, Options>(configuration);
+    this.#configurations.push(opt);
+    return opt;
+  }
+
+  /**
+   * Defines a group of rules from an object of a similar schema to the RuleTester.run() method
+   * Used for API compatibility
+   *
+   * Do not use for new rules
+   */
+  fromObject(
+    defaultConfiguration: Options | null,
+    obj: {
+      valid: (LegacyValidSample<Options> | string)[];
+      invalid: LegacyInvalidSample<MessageIds, Options>[];
+      format?: string;
+    },
+  ): void {
+    const format = obj.format ?? 'ts';
+    if (defaultConfiguration == null) {
+      defaultConfiguration = this.#rule.defaultOptions;
+    }
+
+    obj.valid.forEach(it => {
+      if (typeof it === 'string') {
+        it = {
+          code: it,
+          name: it,
+          options: undefined,
+        };
+
+        const config = this.#findOrMakeConfiguration(
+          it.options ?? defaultConfiguration,
+        );
+
+        config.valid(it.name ?? it.code, it.code, format);
+      }
+    });
+
+    obj.invalid.forEach(it => {
+      const config = this.#findOrMakeConfiguration(
+        it.options ?? defaultConfiguration,
+      );
+
+      config.invalid(
+        it.name ?? it.code,
+        it.code,
+        it.output ?? null,
+        it.errors,
+        format,
+      );
+    });
+  }
+  /**
+   * Gets all configurations and the associated rule from a rule instance
+   * Is a symbol to prevent cluttering up available methods
+   */
+  [DATA](): {
+    configurations: FlatRuleConfiguration<MessageIds, Options>[];
+    rule: RuleModule<MessageIds, Options>;
+    name: string;
+  } {
+    return {
+      configurations: this.#configurations,
+      rule: this.#rule,
+      name: this.#name,
+    };
+  }
+
+  static [CONSTRUCT]<M extends string, O extends unknown[]>(
+    name: string,
+    rule: RuleModule<M, O>,
+  ): FlatRuleConfig<M, O> {
+    return new FlatRuleConfig(name, rule);
+  }
+}
+
+/**
+ * A singular rule configuration, used to define valid and invalid tests
+ */
+export class FlatRuleConfiguration<
+  MessageIds extends string,
+  Config extends unknown[],
+> {
+  #validSamples: ValidSample[];
+  #invalidSamples: InvalidSample<MessageIds>[];
+  #configuration: Config;
+
+  constructor(configuration: Config) {
+    this.#validSamples = [];
+    this.#invalidSamples = [];
+    this.#configuration = configuration;
+  }
+
+  // We return this to allow method chaining
+  valid(name: string, code: string, format?: string): this {
+    this.#validSamples.push({
+      code,
+      name,
+      extension: format,
+    });
+    return this;
+  }
+
+  invalid(
+    name: string,
+    code: string,
+    output: string | null,
+    errors: ExpectedError<MessageIds>[],
+    format?: string,
+  ): this {
+    this.#invalidSamples.push({
+      code,
+      name,
+      output,
+      errors,
+      extension: format,
+    });
+    return this;
+  }
+
+  /**
+   * Gets all samples and configuration from a configuration instance
+   * Is a symbol to prevent cluttering up available methods
+   */
+  [DATA](): {
+    valid: ValidSample[];
+    invalid: InvalidSample<MessageIds>[];
+    configuration: Config;
+  } {
+    return {
+      valid: this.#validSamples,
+      invalid: this.#invalidSamples,
+      configuration: this.#configuration,
+    };
+  }
+}
diff --git a/packages/rule-tester/src/index.ts b/packages/rule-tester/src/index.ts
index 6ea08fc5addb..ecef80c9238f 100644
--- a/packages/rule-tester/src/index.ts
+++ b/packages/rule-tester/src/index.ts
@@ -1,4 +1,5 @@
 export { RuleTester } from './RuleTester';
+export { FlatRuleTester } from './FlatRuleTester';
 export { noFormat } from './noFormat';
 export type {
   InvalidTestCase,
diff --git a/packages/rule-tester/src/types/FlatRuleTester.ts b/packages/rule-tester/src/types/FlatRuleTester.ts
new file mode 100644
index 000000000000..b26fbc5d1675
--- /dev/null
+++ b/packages/rule-tester/src/types/FlatRuleTester.ts
@@ -0,0 +1,112 @@
+import type {
+  AST_NODE_TYPES,
+  AST_TOKEN_TYPES,
+} from '@typescript-eslint/typescript-estree';
+import type { FlatConfig } from '@typescript-eslint/utils/ts-eslint';
+
+export type FileUnawareConfig = Omit<FlatConfig.Config, 'files' | 'ignores'>;
+
+export interface RuleTesterConfig<Formats extends string> {
+  baseOptions: FileUnawareConfig;
+  /**
+   * A list of extension-specific configurations
+   *
+   * You must add an extension-specific configuration for each extension you use (For safety reasons, else you could mistype "ts" like "ys" and it wouldn't yell at you)
+   */
+  extensions: {
+    [K in Formats]: FileUnawareConfig;
+  };
+
+  /**
+   * The directory where fixtures (Virtual files that make TypeScript and eslint plugins happy by providing a virtual file) are located
+   *
+   * compilerServices are mandatory to prevent bugs
+   *
+   * Requires a fixtures directory as such:
+   * ```plaintext
+   * (directory pointed to by fixtureRootDir, must be absolute)
+   *   |-file.ts
+   *   |-file.{any extra extension you need}
+   *   |-tsconfig.json
+   * ```
+   * `tsconfig.json` must be:
+   * ```json
+   * {
+   *   "compilerOptions": { ##SET ANY OPTIONS HERE## },
+   *   "include": ["./file.*", "./file.ts"]
+   * }
+   * ```
+   * In addition, ensure to put your fixture directory INSIDE of the project directory, else type errors will occur
+   */
+  fixtureRootDir: string;
+
+  /**
+   * For future use, do not set.
+   */
+  fixtureMode?: undefined;
+
+  /**
+   * Default extension
+   */
+  defaultExtension?: NoInfer<Formats>;
+}
+
+export interface ExpectedSuggestion<MessageIds extends string> {
+  desc?: string;
+  output?: string;
+  messageId?: MessageIds;
+}
+
+export interface ExpectedError<MessageIds extends string> {
+  line?: number;
+  column?: number;
+  endLine?: number;
+  endColumn?: number;
+  message?: string;
+  messageId?: MessageIds;
+  suggestions?: ExpectedSuggestion<MessageIds>[];
+  type?: /* Trick to make it show up as a string */
+  AST_NODE_TYPES | `${AST_NODE_TYPES}` | AST_TOKEN_TYPES | `${AST_TOKEN_TYPES}`;
+  /**
+   * Not implemented, here for parity, DO NOT USE
+   *
+   * @deprecated
+   */
+  data?: unknown;
+}
+
+export interface Sample {
+  name: string;
+  code: string;
+  extension?: string;
+}
+
+export type ValidSample = Sample;
+
+export interface InvalidSample<MessageIds extends string> extends Sample {
+  errors: ExpectedError<MessageIds>[];
+  output: string | null;
+}
+
+/**
+ * Used for legacy (ESLint RuleTester) compatibility.
+ */
+export interface LegacyValidSample<Options extends unknown[]> {
+  name?: string;
+  code: string;
+  options?: Options;
+}
+
+/**
+ * Used for legacy (core ESLint RuleTester) compatibility,
+ */
+export interface LegacyInvalidSample<
+  MessageIds extends string,
+  Options extends unknown[],
+> {
+  name?: string;
+  code: string;
+  errors: ExpectedError<MessageIds>[];
+  options?: Options;
+  output?: string | null;
+}
diff --git a/packages/rule-tester/tests/FlatRuleTester.test.ts b/packages/rule-tester/tests/FlatRuleTester.test.ts
new file mode 100644
index 000000000000..11d7a4ec9689
--- /dev/null
+++ b/packages/rule-tester/tests/FlatRuleTester.test.ts
@@ -0,0 +1,111 @@
+/// <reference types="lodash" />
+/* eslint-disable @typescript-eslint/explicit-function-return-type */
+import { join } from 'node:path';
+
+import { AST_NODE_TYPES } from '@typescript-eslint/typescript-estree';
+
+import { FlatRuleTester } from '../src/FlatRuleTester';
+
+const tester = new FlatRuleTester({
+  baseOptions: {
+    languageOptions: {
+      parser: require('@typescript-eslint/parser'),
+      parserOptions: {
+        ecmaFeatures: {},
+        ecmaVersion: 2024,
+      },
+    },
+  },
+  extensions: {
+    ts: {},
+  },
+  fixtureRootDir: join(__dirname, './fixtures'),
+});
+
+const myRule = tester.rule('my-rule', {
+  meta: {
+    messages: {
+      disallowedName: 'disallowed',
+      suggest: 'suggest',
+    },
+    schema: [
+      {
+        type: 'array',
+        items: {
+          type: 'string',
+        },
+      },
+    ],
+    type: 'problem',
+    hasSuggestions: true,
+  },
+  create(ctx) {
+    return {
+      FunctionDeclaration(node) {
+        if (
+          ctx.options.length === 1 &&
+          node.id != null &&
+          ctx.options[0].includes(node.id.name)
+        ) {
+          return;
+        }
+
+        return ctx.report({
+          node,
+          messageId: 'disallowedName',
+          suggest: [
+            {
+              fix(fixer) {
+                return [fixer.remove(node)];
+              },
+              messageId: 'suggest',
+            },
+          ],
+        });
+      },
+    };
+  },
+  defaultOptions: [['string']] as [string[]] | [],
+});
+
+const hello = myRule.configuration(['hello']);
+hello.valid('Hello function', 'function hello() {}');
+hello.invalid('Not a hello function', 'function nothello() {}', null, [
+  {
+    messageId: 'disallowedName',
+    suggestions: [
+      {
+        messageId: 'suggest',
+      },
+    ],
+  },
+]);
+
+const again = myRule.configuration(['again']);
+again.valid('Again function', 'function again() {}');
+again.invalid('Not an again function', 'function notagain() {}', null, [
+  {
+    messageId: 'disallowedName',
+    suggestions: [
+      {
+        messageId: 'suggest',
+      },
+    ],
+  },
+]);
+
+myRule.fromObject([], {
+  valid: [],
+  invalid: [
+    {
+      code: `function test() {}`,
+      errors: [
+        {
+          type: AST_NODE_TYPES.FunctionDeclaration,
+        },
+      ],
+    },
+  ],
+});
+
+tester.test();
diff --git a/packages/rule-tester/tests/fixtures/file.ts b/packages/rule-tester/tests/fixtures/file.ts
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/packages/rule-tester/tests/fixtures/tsconfig.json b/packages/rule-tester/tests/fixtures/tsconfig.json
new file mode 100644
index 000000000000..0f2b5aeb649e
--- /dev/null
+++ b/packages/rule-tester/tests/fixtures/tsconfig.json
@@ -0,0 +1,4 @@
+{
+  "compilerOptions": {},
+  "include": ["./file.ts"]
+}
diff --git a/packages/rule-tester/tsconfig.json b/packages/rule-tester/tsconfig.json
index 9cea515ba6b2..6d58b792d5e2 100644
--- a/packages/rule-tester/tsconfig.json
+++ b/packages/rule-tester/tsconfig.json
@@ -4,5 +4,6 @@
     "composite": false,
     "rootDir": "."
   },
-  "include": ["src", "typings", "tests", "tools"]
+  "include": ["src", "typings", "tests", "tools"],
+  "exclude": ["tests/fixtures"]
 }
diff --git a/yarn.lock b/yarn.lock
index 302b1b5bf280..6f4146688e10 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -5713,6 +5713,7 @@ __metadata:
     espree: ^10.0.1
     esprima: ^4.0.1
     json-stable-stringify-without-jsonify: ^1.0.1
+    lodash: ^4.6.2
     lodash.merge: 4.6.2
     mocha: ^10.4.0
     semver: ^7.6.0
@@ -13827,7 +13828,7 @@ __metadata:
   languageName: node
   linkType: hard
 
-"lodash@npm:^4.17.20, lodash@npm:^4.17.21, lodash@npm:~4.17.15":
+"lodash@npm:^4.17.20, lodash@npm:^4.17.21, lodash@npm:^4.6.2, lodash@npm:~4.17.15":
   version: 4.17.21
   resolution: "lodash@npm:4.17.21"
   checksum: eb835a2e51d381e561e508ce932ea50a8e5a68f4ebdd771ea240d3048244a8d13658acbd502cd4829768c56f2e16bdd4340b9ea141297d472517b83868e677f7

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