add commandline main() test units

main_test.go

@@ -0,0 +1,85 @@
+/*
+Copyright © 2023 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 main
+
+import (
+	"bytes"
+	"os"
+	"strings"
+	"testing"
+)
+
+type Cmdline struct {
+	name     string
+	args     string
+	expect   string
+	exitcode int
+}
+
+func TestMain(t *testing.T) {
+	base := "kleingebaeck -c t/config-empty.conf"
+	cmdlines := []Cmdline{
+		{
+			name:     "version",
+			args:     base + " -V",
+			expect:   "This is",
+			exitcode: 0,
+		},
+		{
+			name:     "help",
+			args:     base + " -h",
+			expect:   "Usage:",
+			exitcode: 0,
+		},
+		{
+			name:     "debug",
+			args:     base + " -d",
+			expect:   "program_info",
+			exitcode: 1,
+		},
+		{
+			name:     "no-args-no-user",
+			args:     base,
+			expect:   "invalid or no user id",
+			exitcode: 1,
+		},
+		//  FIXME: add  scrape  tests as  well, re-use  scrape_test.go
+		// stuff or simply move all of it to here
+	}
+
+	oldargs := os.Args
+	defer func() { os.Args = oldargs }()
+
+	for _, c := range cmdlines {
+		var buf bytes.Buffer
+		os.Args = strings.Split(c.args, " ")
+
+		ret := Main(&buf)
+
+		if ret != c.exitcode {
+			t.Errorf("%s with cmd <%s> did not exit with %d but %d",
+				c.name, c.args, c.exitcode, ret)
+		}
+
+		if !strings.Contains(buf.String(), c.expect) {
+			t.Errorf("%s with cmd <%s> output did not match.\nExpect: %s\n   Got: %s\n",
+				c.name, c.args, c.expect, buf.String())
+		}
+	}
+
+}

t/config-empty.conf

@@ -0,0 +1,2 @@
+# empty config for Main() unit tests to force unit tests NOT to use an
+# eventually existing ~/.kleingebaeck!