add createInvalidArgumentError(); see #3676

- updated error code table in docs
- all other changes in docs are from prettier
- updated `--compilers` test
- rename "not supported" error to "unsupported" error
- rename "undefined error" error to "invalid exception" error
- remove "invalid argument" factory; use "unsupported" factory
- doc fixes
- move `utils.getError` to `Runnable.toValueOrError`, since it's only used there; use more appropriate name
- remove `utils.undefinedError`; use `createInvalidExceptionError` instead.
- fix coverage problems
- add my `unexpected-eventemitter` plugin, which helps test `EventEmitter` behavior

karma.conf.js

@@ -156,6 +156,7 @@ module.exports = config => {
     require.resolve('unexpected/unexpected'),
     {pattern: require.resolve('unexpected/unexpected.js.map'), included: false},
     require.resolve('unexpected-sinon'),
+    require.resolve('unexpected-eventemitter/dist/unexpected-eventemitter.js'),
     require.resolve('./test/browser-specific/setup')
   );
 

lib/cli/run.js

@@ -8,8 +8,8 @@
  */
 
 const Mocha = require('../mocha');
-const ansi = require('ansi-colors');
 const {
+  createUnsupportedError,
   createInvalidArgumentValueError,
   createMissingArgumentError
 } = require('../errors');
@@ -268,9 +268,9 @@ exports.builder = yargs =>
       }
 
       if (argv.compilers) {
-        throw createInvalidArgumentValueError(
+        throw createUnsupportedError(
           `--compilers is DEPRECATED and no longer supported.
-          See ${ansi.cyan('https://git.io/vdcSr')} for migration information.`
+          See https://git.io/vdcSr for migration information.`
         );
       }
 

lib/errors.js

@@ -7,7 +7,7 @@
  */
 
 /**
- * Creates an error object used when no files to be tested could be found using specified pattern.
+ * Creates an error object to be thrown when no files to be tested could be found using specified pattern.
  *
  * @public
  * @param {string} message - Error message to be displayed.
@@ -22,7 +22,7 @@ function createNoFilesMatchPatternError(message, pattern) {
 }
 
 /**
- * Creates an error object used when the reporter specified in the options was not found.
+ * Creates an error object to be thrown when the reporter specified in the options was not found.
  *
  * @public
  * @param {string} message - Error message to be displayed.
@@ -37,7 +37,7 @@ function createInvalidReporterError(message, reporter) {
 }
 
 /**
- * Creates an error object used when the interface specified in the options was not found.
+ * Creates an error object to be thrown when the interface specified in the options was not found.
  *
  * @public
  * @param {string} message - Error message to be displayed.
@@ -52,20 +52,20 @@ function createInvalidInterfaceError(message, ui) {
 }
 
 /**
- * Creates an error object used when the type of output specified was not supported.
+ * Creates an error object to be thrown when a behavior, option, or parameter is unsupported.
  *
  * @public
  * @param {string} message - Error message to be displayed.
  * @returns {Error} instance detailing the error condition
  */
-function createNotSupportedError(message) {
+function createUnsupportedError(message) {
   var err = new Error(message);
-  err.code = 'ERR_MOCHA_NOT_SUPPORTED';
+  err.code = 'ERR_MOCHA_UNSUPPORTED';
   return err;
 }
 
 /**
- * Creates an error object used when an argument is missing.
+ * Creates an error object to be thrown when an argument is missing.
  *
  * @public
  * @param {string} message - Error message to be displayed.
@@ -78,7 +78,7 @@ function createMissingArgumentError(message, argument, expected) {
 }
 
 /**
- * Creates an error object used when an argument did not use the supported type
+ * Creates an error object to be thrown when an argument did not use the supported type
  *
  * @public
  * @param {string} message - Error message to be displayed.
@@ -96,7 +96,7 @@ function createInvalidArgumentTypeError(message, argument, expected) {
 }
 
 /**
- * Creates an error object used when an argument did not use the supported value
+ * Creates an error object to be thrown when an argument did not use the supported value
  *
  * @public
  * @param {string} message - Error message to be displayed.
@@ -115,25 +115,27 @@ function createInvalidArgumentValueError(message, argument, value, reason) {
 }
 
 /**
- * Creates an error object used when an error was thrown but no details were specified.
+ * Creates an error object to be thrown when an exception was caught, but the `Error` is falsy or undefined.
  *
  * @public
  * @param {string} message - Error message to be displayed.
  * @returns {Error} instance detailing the error condition
  */
-function createUndefinedError(message) {
+function createInvalidExceptionError(message, value) {
   var err = new Error(message);
-  err.code = 'ERR_MOCHA_UNDEFINED_ERROR';
+  err.code = 'ERR_MOCHA_INVALID_EXCEPTION';
+  err.valueType = typeof value;
+  err.value = value;
   return err;
 }
 
 module.exports = {
   createInvalidArgumentTypeError: createInvalidArgumentTypeError,
   createInvalidArgumentValueError: createInvalidArgumentValueError,
+  createInvalidExceptionError: createInvalidExceptionError,
   createInvalidInterfaceError: createInvalidInterfaceError,
   createInvalidReporterError: createInvalidReporterError,
   createMissingArgumentError: createMissingArgumentError,
   createNoFilesMatchPatternError: createNoFilesMatchPatternError,
-  createNotSupportedError: createNotSupportedError,
-  createUndefinedError: createUndefinedError
+  createUnsupportedError: createUnsupportedError
 };

lib/reporters/xunit.js

@@ -12,6 +12,7 @@ var fs = require('fs');
 var mkdirp = require('mkdirp');
 var path = require('path');
 var errors = require('../errors');
+var createUnsupportedError = errors.createUnsupportedError;
 var constants = require('../runner').constants;
 var EVENT_TEST_PASS = constants.EVENT_TEST_PASS;
 var EVENT_TEST_FAIL = constants.EVENT_TEST_FAIL;
@@ -20,7 +21,6 @@ var EVENT_TEST_PENDING = constants.EVENT_TEST_PENDING;
 var STATE_FAILED = require('../runnable').constants.STATE_FAILED;
 var inherits = utils.inherits;
 var escape = utils.escape;
-var createNotSupportedError = errors.createNotSupportedError;
 
 /**
  * Save timer references to avoid Sinon interfering (see GH-237).
@@ -58,7 +58,7 @@ function XUnit(runner, options) {
   if (options && options.reporterOptions) {
     if (options.reporterOptions.output) {
       if (!fs.createWriteStream) {
-        throw createNotSupportedError('file output not supported in browser');
+        throw createUnsupportedError('file output not supported in browser');
       }
 
       mkdirp.sync(path.dirname(options.reporterOptions.output));

lib/runnable.js

@@ -5,6 +5,8 @@ var Pending = require('./pending');
 var debug = require('debug')('mocha:runnable');
 var milliseconds = require('ms');
 var utils = require('./utils');
+var createInvalidExceptionError = require('./errors')
+  .createInvalidExceptionError;
 
 /**
  * Save timer references to avoid Sinon interfering (see GH-237).
@@ -355,7 +357,7 @@ Runnable.prototype.run = function(fn) {
       callFnAsync(this.fn);
     } catch (err) {
       emitted = true;
-      done(utils.getError(err));
+      done(Runnable.toValueOrError(err));
     }
     return;
   }
@@ -378,7 +380,7 @@ Runnable.prototype.run = function(fn) {
     }
   } catch (err) {
     emitted = true;
-    done(utils.getError(err));
+    done(Runnable.toValueOrError(err));
   }
 
   function callFn(fn) {
@@ -462,7 +464,8 @@ var constants = utils.defineConstants(
    * @static
    * @alias constants
    * @enum {string}
-   */ {
+   */
+  {
     /**
      * Value of `state` prop when a `Runnable` has failed
      */
@@ -474,4 +477,20 @@ var constants = utils.defineConstants(
   }
 );
 
+/**
+ * Given `value`, return identity if truthy, otherwise create an "invalid exception" error and return that.
+ * @param {*} [value] - Value to return, if present
+ * @returns {*|Error} `value`, otherwise an `Error`
+ * @private
+ */
+Runnable.toValueOrError = function(value) {
+  return (
+    value ||
+    createInvalidExceptionError(
+      'Runnable failed with falsy or undefined exception. Please throw an Error instead.',
+      value
+    )
+  );
+};
+
 Runnable.constants = constants;

lib/runner.js

@@ -17,7 +17,8 @@ var STATE_PASSED = Runnable.constants.STATE_PASSED;
 var stackFilter = utils.stackTraceFilter();
 var stringify = utils.stringify;
 var type = utils.type;
-var undefinedError = utils.undefinedError;
+var createInvalidExceptionError = require('./errors')
+  .createInvalidExceptionError;
 
 /**
  * Non-enumerable globals.
@@ -771,18 +772,13 @@ Runner.prototype.runSuite = function(suite, fn) {
  */
 Runner.prototype.uncaught = function(err) {
   if (err) {
-    debug(
-      'uncaught exception %s',
-      err ===
-        function() {
-          return this;
-        }.call(err)
-        ? err.message || err
-        : err
-    );
+    debug('uncaught exception %O', err);
   } else {
-    debug('uncaught undefined exception');
-    err = undefinedError();
+    debug('uncaught undefined/falsy exception');
+    err = createInvalidExceptionError(
+      'Caught falsy/undefined exception which would otherwise be uncaught. No stack trace found; try a debugger',
+      err
+    );
   }
 
   if (!isError(err)) {
@@ -827,6 +823,7 @@ Runner.prototype.uncaught = function(err) {
       this.hookUp(HOOK_TYPE_AFTER_EACH, this.next);
       return;
     }
+    debug(runnable);
 
     // recover from hooks
     var errSuite = this.suite;

lib/utils.js

@@ -18,7 +18,6 @@ var he = require('he');
 var errors = require('./errors');
 var createNoFilesMatchPatternError = errors.createNoFilesMatchPatternError;
 var createMissingArgumentError = errors.createMissingArgumentError;
-var createUndefinedError = errors.createUndefinedError;
 
 /**
  * Ignored directories.
@@ -580,29 +579,6 @@ exports.lookupFiles = function lookupFiles(filepath, extensions, recursive) {
   return files;
 };
 
-/**
- * Generate an undefined error with a message warning the user.
- *
- * @return {Error}
- */
-
-exports.undefinedError = function() {
-  return createUndefinedError(
-    'Caught undefined error, did you throw without specifying what?'
-  );
-};
-
-/**
- * Generate an undefined error if `err` is not defined.
- *
- * @param {Error} err
- * @return {Error}
- */
-
-exports.getError = function(err) {
-  return err || exports.undefinedError();
-};
-
 /**
  * process.emitWarning or a polyfill
  * @see https://nodejs.org/api/process.html#process_process_emitwarning_warning_options

package-scripts.js

@@ -115,7 +115,7 @@ module.exports = {
         integration: {
           script: test(
             'integration',
-            '--timeout 10000 --slow 3750 "test/integration/*.spec.js"'
+            '--timeout 10000 --slow 3750 "test/integration/**/*.spec.js"'
           ),
           description: 'Run Node.js integration tests',
           hiddenFromHelp: true

package.json

@@ -560,6 +560,7 @@
     "through2": "^3.0.0",
     "to-vfile": "^5.0.2",
     "unexpected": "^10.39.2",
+    "unexpected-eventemitter": "^1.1.3",
     "unexpected-sinon": "^10.10.1",
     "uslug": "^1.0.4",
     "watchify": "^3.7.0"

test/browser-specific/setup.js

@@ -4,4 +4,5 @@ process.stdout = require('browser-stdout')();
 
 global.expect = global.weknowhow.expect
   .clone()
-  .use(global.weknowhow.unexpectedSinon);
+  .use(global.weknowhow.unexpectedSinon)
+  .use(global.unexpectedEventEmitter);

test/integration/helpers.js

@@ -174,7 +174,16 @@ module.exports = {
    */
   resolveFixturePath: resolveFixturePath,
 
-  toJSONRunResult: toJSONRunResult
+  toJSONRunResult: toJSONRunResult,
+
+  /**
+   * Given a regexp-like string, escape it so it can be used with the `RegExp` constructor
+   * @param {string} str - string to be escaped
+   * @returns {string} Escaped string
+   */
+  escapeRegExp: function escapeRegExp(str) {
+    return str.replace(/[.*+?^${}()|[\]\\]/g, '\\$&'); // $& means the whole matched string
+  }
 };
 
 /**