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. 26 documented errors.

Code / MessageTypeSeverityTags
This script is intended to be run as a worker (by the…
exception error parallel-mode, worker-threads, misuse
Not enough arguments following
exception error cli, argument-validation, yargs
ERR_MOCHA_NO_FILES_MATCH_PATTERN
Cannot find any files matching pattern
error_code error cli, glob, no-files, error-code
ERR_MOCHA_UNSUPPORTED
file output not supported in browser
error_code error browser, reporter, unsupported-feature
ERR_MOCHA_INSTANCE_ALREADY_DISPOSED
Mocha instance is already disposed, it cannot be used again.
exception error mocha, instance-lifecycle, programmatic-api, state-error
invalid state transition
exception error parallel, state-machine, runner
async skip; aborting execution
exception warning test-execution, skip, async
Warning
console warning cli, file-glob, warning
ERR_MOCHA_INVALID_PLUGIN_IMPLEMENTATION
mochaHooks must be an object or a function returning (or fulfilling with) an…
error_code error plugins, root-hooks, configuration
Not enough non-option arguments: got 0, need at least 1
exception error cli, argument-validation, init
ERR_MOCHA_INVALID_ARG_TYPE
Empty `eventName` string argument
error_code error serializer, parallel-mode, argument-validation
ERR_MOCHA_UNPARSABLE_FILE
Unable to read
error_code error config, package-json, file-io, cli
ERR_MOCHA_INVALID_REPORTER (reporter) or ERR_MOCHA_INVALID_INTERFACE (ui)
"-- " can only be specified once
error_code error cli, reporter, ui, duplicate-option
sync skip; aborting execution
exception warning test-execution, skip, pending
Missing runner argument
exception error reporters, argument-validation, typeerror
Invalid argument; expected a non-empty object
exception error validation, typeerror, internal-api
ERR_MOCHA_INVALID_PLUGIN_DEFINITION
pluginDef is non-object or falsy
error_code error plugins, api-misuse, argument-validation
ERR_MOCHA_INVALID_ARG_VALUE
invalid reporter option
error_code error cli, reporter-options, arguments, validation
Unsupported URL protocol
exception error esm, url, file-loading
ERR_MOCHA_INVALID_REPORTER
${err.message}
exception error reporter, module-loading
ERR_MOCHA_INVALID_INTERFACE
invalid interface
exception error ui, interface, config
unknown pluginType
exception error internal, plugin, error-factory
ERR_MOCHA_FATAL
Object missing ID received in event data
exception critical mocha, parallel, serialization, internal-error
ERR_MOCHA_INSTANCE_ALREADY_RUNNING
Cannot dispose while the mocha instance is still running tests.
exception error mocha, instance-lifecycle, async, programmatic-api
invalid or unsupported TAP version
exception error reporters, tap, option-validation
ERR_MOCHA_MISSING_ARGUMENT
"--invert" requires one of "--fgrep
validation error cli, argument-validation