Added more unittests, fixed hour format output (#4)

* little refactoring
* added more tests, fixed hour format output
* bump version

cmd/writer_test.go

@@ -0,0 +1,81 @@
+/*
+Copyright © 2025 Thomas von Dein
+
+This program is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program. If not, see <http://www.gnu.org/licenses/>.
+*/
+
+package cmd
+
+import (
+	"fmt"
+	"testing"
+	"time"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestDuration(t *testing.T) {
+	var tests = []struct {
+		format   string
+		duration time.Duration
+		want     string
+	}{
+		{"day", time.Hour * 24, "1.00 days"},
+		{"dur", time.Hour * 24, "24h0m0s"},
+		{"hour", time.Hour * 24, "24.00 hours"},
+		{"min", time.Minute * 20, "20.00 minutes"},
+		{"min", time.Minute*20 + time.Second*30, "20.50 minutes"},
+		{"sec", time.Second * 30, "30.00 seconds"},
+		{"ms", time.Second * 30, "30000 milliseconds"},
+	}
+
+	for _, tt := range tests {
+		testname := fmt.Sprintf("formatduration-%s", tt.format)
+		t.Run(testname, func(t *testing.T) {
+			tpdur := TPduration{Data: tt.duration}
+			tpdur.Unit = true
+			tpdur.Format = tt.format
+
+			out := tpdur.String()
+			assert.Equal(t, tt.want, out)
+		})
+	}
+}
+
+func TestDatetime(t *testing.T) {
+	var now = time.Date(2025, 9, 25, 12, 30, 00, 0, time.UTC)
+
+	var tests = []struct {
+		format   string
+		datetime time.Time
+		want     string
+	}{
+		{"rfc3339", now, "2025-09-25T12:30:00Z"},
+		{"date", now, "2025-09-25"},
+		{"time", now, "12:30:00"},
+		{"unix", now, "1758803400"},
+		{"datetime", now, "2025-09-25 12:30:00 +0000 UTC"},
+	}
+
+	for _, tt := range tests {
+		testname := fmt.Sprintf("formatdatetime-%s", tt.format)
+		t.Run(testname, func(t *testing.T) {
+			tpdat := TPdatetime{Data: tt.datetime}
+			tpdat.Format = tt.format
+
+			out := tpdat.String()
+			assert.Equal(t, tt.want, out)
+		})
+	}
+}