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Powerful Command-Line Applications in Go (page 24): suggestion for TestMain

telemachus

telemachus

Powerful Command-Line Applications in Go (page 24): suggestion for TestMain

@rgerardi

On a later page, the author writes “Before running the tests, delete the file .todo.json if it exists from a previous test or the test execution will fail” (page 26).

In order to avoid this problem and to save readers trouble, I suggest adding the following to the top of TestMain:

// Let’s make sure we are not in a bad state: remove any cruft first.
os.Remove(binName)
os.Remove(fileName)

This way, the test runner cleans up any old binary or leftover .todo.json files before a new binary is created or any tests run. This protects users from broken tests due to carelessness if they forget to remove an old file.

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rgerardi

rgerardi

Author of Powerful Command-Line Applications in Go

Thank you for the suggestion. I am taking a look at this.

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