Logging in tests

Often additional logging functionality is useful for tests to show the state of critical variables, especially if a failure occurs. By default, the Go test executor does not print any logging information if tests pass, but if a test fails, the logging information is also included in the output.

How to do it...

1. Use testing.T.Log and testing.T.Logf functions to record log messages in tests:

   func TestSortTimeAscending(t *testing.T) {
     ...
     t.Logf("Input: %v",input)
     output:=SortTimes(input,true)
     t.Logf("Output: %v", output)

2. Run the tests. If the test passes, no log information will be printed. If the test fails, logs will be printed.

   To run the tests with logs, use the -v flag:

   $ go test -v
   === RUN   TestSortTimesAscending
       sort_test.go:17: Input: [2023-02-01 12:08:37 -0700 MST 2021-05-06 09:48:11 -0600 MDT 2022-11-13 17:13:54 -0700 MST 2022-06-23 22:29:28 -0600 MDT 2023-03-17 04:05:09 -0600 MDT]
       sort_test.go:19: Output: [2021-05-06 09:48:11 -0600 MDT 2022-06-23 22:29:28 -0600 MDT 2022-11-13 17:13:54 -0700 MST 2023-02-01 12:08:37 -0700 MST 2023-03-17 04:05:09 -0600 MDT]
   --- PASS: TestSortTimesAscending (0.00s)