ErrLookup › mochajs/mocha

mochajs/mocha

☕️ Classic, reliable, trusted test framework for Node.js and the browser · JavaScript · 73 source files

Analyzed at 6bcbee4fd9 on 2026-09-01. 43 documented errors.

Code / MessageTypeSeverityTags
Not enough non-option arguments: got 0, need at least 1
exception error cli, argument-validation, init
Not enough arguments following: ${name}
exception error cli, argument-validation, yargs
unknown pluginType "${pluginType}"
exception error internal, plugin, error-factory
Missing runner argument
exception error reporters, argument-validation, typeerror
invalid or unsupported TAP version: ${JSON.stringify(tapVers
exception error reporters, tap, option-validation
sync skip; aborting execution
exception warning test-execution, skip, pending
async skip; aborting execution
exception warning test-execution, skip, async
Missing runner argument
exception error stats, runner, argument-validation
Unsupported URL protocol "${parsed.protocol}". Only "file:"
exception error esm, url, file-loading
invalid state transition: ${state} => ${newState}
exception error parallel, state-machine, runner
This script is intended to be run as a worker (by the `worke
exception error parallel-mode, worker-threads, misuse
Invalid argument; expected a non-empty object
exception error validation, typeerror, internal-api
Warning: ${warning.message}
console warning cli, file-glob, warning
ERR_MOCHA_NO_FILES_MATCH_PATTERN
Cannot find any files matching pattern "${filepath}"
error_code error cli, glob, no-files, error-code
ERR_MOCHA_INVALID_ARG_TYPE
Argument '${extensions}' required when argument '${filepath}' is a directory
error_code error cli, validation, arguments, error-code
ERR_MOCHA_INVALID_ARG_TYPE
Mocha flag '${flag}' given invalid option: '${numericArg}'
error_code error
ERR_MOCHA_UNSUPPORTED
Option ${numericArg} is unsupported by the mocha cli
error_code error
ERR_MOCHA_FORBIDDEN_EXCLUSIVITY
`.only` forbidden by --forbid-only (or "`.only` is not supported in parallel mod
error_code error
ERR_MOCHA_UNSUPPORTED
Pending test forbidden
error_code error
ERR_MOCHA_INVALID_ARG_TYPE
Suite "${suite.fullTitle()}" was defined but no callback was supplied. Supply a
error_code error
ERR_MOCHA_INVALID_ARG_TYPE
Empty `eventName` string argument
error_code error serializer, parallel-mode, argument-validation
ERR_MOCHA_INVALID_PLUGIN_IMPLEMENTATION
mochaHooks must be an object or a function returning (or fulfilling with) an obj
error_code error plugins, root-hooks, configuration
ERR_MOCHA_INVALID_PLUGIN_DEFINITION
pluginDef is non-object or falsy
error_code error plugins, api-misuse, argument-validation
ERR_MOCHA_UNSUPPORTED
file output not supported in browser
error_code error browser, reporter, unsupported-feature
ERR_MOCHA_UNSUPPORTED
file output not supported in browser
error_code error browser, reporter, xunit, unsupported-feature
ERR_MOCHA_INVALID_ARG_TYPE
Test argument "title" should be a string. Received type "${typeof title}"
error_code error arguments, type-error, test-constructor
ERR_MOCHA_UNPARSABLE_FILE
Unable to read/parse ${filepath}: ${err}
error_code error config, parse-error, cli
ERR_MOCHA_UNPARSABLE_FILE
Unable to read ${filepath}: ${err}
error_code error config, package-json, file-io, cli
ERR_MOCHA_INVALID_REPORTER (reporter) or ERR_MOCHA_INVALID_INTERFACE (ui)
"--${pluginType}" can only be specified once
error_code error cli, reporter, ui, duplicate-option
ERR_MOCHA_INVALID_ARG_VALUE
invalid reporter option '${opt}'
error_code error cli, reporter-options, arguments, validation
ERR_MOCHA_UNSUPPORTED
Arguments ${oneAndDoneOptions.join(" and ")} are mutually exclusive
exception error cli, argument-validation
ERR_MOCHA_MISSING_ARGUMENT
"--invert" requires one of "--fgrep <str>" or "--grep <regexp>"
validation error cli, argument-validation
ERR_MOCHA_INVALID_REPORTER
${err.message}
exception error reporter, module-loading
ERR_MOCHA_INVALID_INTERFACE
invalid interface '${ui}'
exception error ui, interface, config
ERR_MOCHA_UNSUPPORTED
unloadFile() is only supported in a Node.js environment
exception error browser, node-only, api-misuse
ERR_MOCHA_INSTANCE_ALREADY_DISPOSED
Mocha instance is already disposed, it cannot be used again.
exception error mocha, instance-lifecycle, programmatic-api, state-error
ERR_MOCHA_INSTANCE_ALREADY_RUNNING
Cannot dispose while the mocha instance is still running tests.
exception error mocha, instance-lifecycle, async, programmatic-api
ERR_MOCHA_INVALID_ARG_TYPE
Expected a non-empty filepath
validation error mocha, parallel, argument-validation, worker-pool
ERR_MOCHA_FATAL
Object missing ID received in event data
exception critical mocha, parallel, serialization, internal-error
ERR_MOCHA_INVALID_ARG_TYPE
Expected a non-empty "filepath" argument
validation error mocha, parallel, worker, argument-validation
ERR_MOCHA_INVALID_ARG_VALUE
run() was unable to deserialize the options
validation error
ERR_MOCHA_FATAL
Test failed after root suite execution completed!
exception error
ERR_MOCHA_UNSUPPORTED
workerReporter() not supported in serial mode
exception error