test(cli): add failing pretend quiet dry-run coverage

internal/homesick/core/exec_test.go

@@ -77,3 +77,13 @@ func (s *ExecSuite) TestExecAll_RunsCommandForEachCastle() {
 	require.NoError(s.T(), s.app.ExecAll([]string{"basename \"$PWD\""}))
 	require.Equal(s.T(), "alpha\nzeta\n", s.stdout.String())
 }
+
+func (s *ExecSuite) TestExec_PretendDoesNotExecuteCommand() {
+	castleRoot := s.createCastle("dotfiles")
+	target := filepath.Join(castleRoot, "should-not-exist")
+
+	s.app.Pretend = true
+	require.NoError(s.T(), s.app.Exec("dotfiles", []string{"touch should-not-exist"}))
+	require.NoFileExists(s.T(), target)
+	require.Contains(s.T(), s.stdout.String(), "Would execute")
+}