How to Test for CLI output in go test file using cobra

Question

I am writing a program in go with Cobra CLI framework , right now I am working on writing test files to the CLI, i have some prints that i want to check if correct but i couldn't figure out how to get the prints and compare them my code is like this:

func TestCommand(t *testing.T) {
    // Start the mock server
    mockServer, err := mock.StartMockServer()
    if err != nil {
        t.Fatalf("Failed to start mock server: %v", err)
    }
    defer mockServer.Stop() // Ensure the server is stopped after the test

    // Wait for a moment to ensure the server is up
    time.Sleep(100 * time.Millisecond)

    // Capture output
    var buf bytes.Buffer
    rootCmd := cmd.NewRootCommand()
    rootCmd.SetOut(&buf)

    // Execute the command
    rootCmd.SetArgs([]string{"version"})
    if err := rootCmd.Execute(); err != nil {
        t.Fatalf("Execute() failed: %v", err)
    }
    // Check expected output
    if buf.String() != ExpectedVersion {
        t.Errorf("Expected %q, got %q", ExpectedVersion, buf.String())
    }
}

and the output when i run go test is

=== RUN   TestCommand
Connecting to server on localhost:4466...
Version:  v0.22.0-15-gd09d7fca0d

    /home/shoham/TraceeClient/cmd/cmd_test.go:44: Expected "Version: v0.22.0-15-gd09d7fca0d\n", got ""
--- FAIL: TestVersionCommand (0.17s)

as you can see the version prints to the screen but the buffer dont collect it, how can i fix this issue?

i have tried to print it diffrently then I use before, I have used the fmt.Println and fmt.Printf for this prints and it still didnt work when I try to use each one