How to run test cases in a specified file?

My package test cases are scattered across multiple files, if I run go test it runs all test cases in the package.

It is unnecessary to run all of them though. Is there a way to specify a file for go test to run, so that it only runs test cases defined in the file?

There are two ways. The easy one is to use the -run flag and provide a pattern matching names of the tests you want to run.

Example:

$ go test packageName -run NameOfTest

See the docs for more info.

Note that the -run flag may also run other tests if they contain the string NameOfTest, as the -run flag matches a regexp.

So to ensure that only a test named exactly 'NameOfTest' is run,
one has to use the regexp ^NameOfTest$:

$ go test -run "^NameOfTest$"

The other way is to name the specific file, containing the tests you want to run:

$ go test foo_test.go

But there's a catch. This works well if:

• foo.go is in package foo.

• foo_test.go is in package foo_test and imports 'foo'.

If foo_test.go and foo.go are the same package (a common case) then you must name all other files required to build foo_test. In this example it would be:

$ go test foo_test.go foo.go

I'd recommend to use the -run pattern. Or, where/when possible, always run all package tests.

Stack Overflow Q#16935965, score: 557