refactor!: remove unused legacy errors.js functions

lib/errors.js

@@ -12,56 +12,10 @@ const { constants } = require("./error-constants.mjs");
 const { isCI } = require("./utils");
 
 /**
- * Contains error codes, factory functions to create throwable error objects,
- * and warning/deprecation functions.
+ * Contains error codes and factory functions to create throwable error objects
  * @module
  */
 
-/**
- * process.emitWarning or a polyfill
- * @see https://nodejs.org/api/process.html#process_process_emitwarning_warning_options
- * @ignore
- */
-const emitWarning = (msg, type) => {
-  if (process.emitWarning) {
-    process.emitWarning(msg, type);
-  } else {
-    /* istanbul ignore next */
-    process.nextTick(function () {
-      console.warn(type + ": " + msg);
-    });
-  }
-};
-
-/**
- * Show a deprecation warning. Each distinct message is only displayed once.
- * Ignores empty messages.
- *
- * @param {string} [msg] - Warning to print
- * @private
- */
-const deprecate = (msg) => {
-  msg = String(msg);
-  if (msg && !deprecate.cache[msg]) {
-    deprecate.cache[msg] = true;
-    emitWarning(msg, "DeprecationWarning");
-  }
-};
-deprecate.cache = {};
-
-/**
- * Show a generic warning.
- * Ignores empty messages.
- *
- * @param {string} [msg] - Warning to print
- * @private
- */
-const warn = (msg) => {
-  if (msg) {
-    emitWarning(msg);
-  }
-};
-
 /**
  * A set containing all string values of all Mocha error constants, for use by {@link isMochaError}.
  * @private
@@ -235,22 +189,6 @@ function createInvalidLegacyPluginError(message, pluginType, pluginId) {
   }
 }
 
-/**
- * **DEPRECATED**.  Use {@link createInvalidLegacyPluginError} instead  Dynamically creates a plugin-type-specific error based on plugin type
- * @deprecated
- * @param {string} message - Error message
- * @param {"reporter"|"interface"} pluginType - Plugin type. Future: expand as needed
- * @param {string} [pluginId] - Name/path of plugin, if any
- * @throws When `pluginType` is not known
- * @public
- * @static
- * @returns {Error}
- */
-function createInvalidPluginError(...args) {
-  deprecate("Use createInvalidLegacyPluginError() instead");
-  return createInvalidLegacyPluginError(...args);
-}
-
 /**
  * Creates an error object to be thrown when a mocha object's `run` method is executed while it is already disposed.
  * @param {string} message The error message to be displayed.
@@ -430,7 +368,6 @@ module.exports = {
   createInvalidInterfaceError,
   createInvalidLegacyPluginError,
   createInvalidPluginDefinitionError,
-  createInvalidPluginError,
   createInvalidPluginImplementationError,
   createInvalidReporterError,
   createMissingArgumentError,
@@ -441,7 +378,5 @@ module.exports = {
   createTimeoutError,
   createUnparsableFileError,
   createUnsupportedError,
-  deprecate,
   isMochaError,
-  warn,
 };

test/unit/errors.spec.js

@@ -83,82 +83,6 @@ describe("Errors", function () {
     });
   });
 
-  describe("deprecate()", function () {
-    var emitWarning;
-
-    beforeEach(function () {
-      if (process.emitWarning) {
-        emitWarning = process.emitWarning;
-        sinon.stub(process, "emitWarning");
-      } else {
-        process.emitWarning = sinon.spy();
-      }
-      errors.deprecate.cache = {};
-    });
-
-    afterEach(function () {
-      // if this is not set, then we created it, so we should remove it.
-      if (!emitWarning) {
-        delete process.emitWarning;
-      }
-    });
-
-    it("should coerce its parameter to a string", function () {
-      errors.deprecate(1);
-      expect(process.emitWarning, "to have a call satisfying", [
-        "1",
-        "DeprecationWarning",
-      ]);
-    });
-
-    it("should cache the message", function () {
-      errors.deprecate("foo");
-      errors.deprecate("foo");
-      expect(process.emitWarning, "was called times", 1);
-    });
-
-    it("should ignore falsy messages", function () {
-      errors.deprecate("");
-      expect(process.emitWarning, "was not called");
-    });
-  });
-
-  describe("warn()", function () {
-    var emitWarning;
-
-    beforeEach(function () {
-      if (process.emitWarning) {
-        emitWarning = process.emitWarning;
-        sinon.stub(process, "emitWarning");
-      } else {
-        process.emitWarning = sinon.spy();
-      }
-    });
-
-    afterEach(function () {
-      // if this is not set, then we created it, so we should remove it.
-      if (!emitWarning) {
-        delete process.emitWarning;
-      }
-    });
-
-    it("should call process.emitWarning", function () {
-      errors.warn("foo");
-      expect(process.emitWarning, "was called times", 1);
-    });
-
-    it("should not cache messages", function () {
-      errors.warn("foo");
-      errors.warn("foo");
-      expect(process.emitWarning, "was called times", 2);
-    });
-
-    it("should ignore falsy messages", function () {
-      errors.warn("");
-      expect(process.emitWarning, "was not called");
-    });
-  });
-
   describe("isMochaError()", function () {
     describe("when provided an Error object having a known Mocha error code", function () {
       it("should return true", function () {

test/unit/mocha.spec.js

@@ -4,7 +4,6 @@ var sinon = require("sinon");
 var EventEmitter = require("node:events").EventEmitter;
 var Mocha = require("../../lib/mocha");
 var utils = require("../../lib/utils");
-const errors = require("../../lib/errors");
 
 describe("Mocha", function () {
   /**
@@ -78,7 +77,6 @@ describe("Mocha", function () {
     Suite = sinon.stub(Mocha, "Suite").returns(suite);
     Suite.constants = {};
 
-    sinon.stub(errors, "warn");
     sinon.stub(utils, "isString");
     sinon.stub(utils, "noop");
   });

test/unit/suite.spec.js

@@ -3,7 +3,6 @@
 const Mocha = require("../../lib/mocha");
 const { Suite, Test, Context } = Mocha;
 const sinon = require("sinon");
-const errors = require("../../lib/errors");
 
 function supportsFunctionNames() {
   return function foo() {}.name === "foo";
@@ -527,10 +526,6 @@ describe("Suite", function () {
     });
 
     describe("constructor", function () {
-      beforeEach(function () {
-        sinon.stub(errors, "deprecate");
-      });
-
       /* eslint no-new: off */
       it("should throw an error if the title isn't a string", function () {
         expect(function () {