By default, mocha looks for the glob "./test/*.js", so you may want to put your tests in test/ folder. If you want to include subdirectories, pass the --recursive option.
To configure where mocha looks for tests, you may pass your own glob:
$ mocha --recursive "./spec/*.js"Some shells support recursive matching by using the globstar (**) wildcard. Bash >= 4.3 supports this with the globstar option which must be enabled to get the same results as passing the --recursive option (ZSH and Fish support this by default). With recursive matching enabled, the following is the same as passing --recursive:
$ mocha "./spec/**/*.js"Note: Double quotes around the glob are recommended for portability.