Capture coverage of integration tests

To capture the coverage also for the integration tests,
a test only executing the cmd.Run function is used.

The test always exits with code 0 and prints the
real exit code to stdout. Otherwise no coverage
report is generated.

Those changes enable a more accurate coverage report
for future contributions.

main_test.go

@@ -0,0 +1,63 @@
+//go:build testruncli
+// +build testruncli
+
+package main
+
+import (
+	"flag"
+	"fmt"
+	"math/rand"
+	"os"
+	"strings"
+	"testing"
+	"time"
+
+	"github.com/aptly-dev/aptly/aptly"
+	"github.com/aptly-dev/aptly/cmd"
+)
+
+func filterOutTestArgs(args []string) (out []string) {
+	for _, arg := range args {
+		if !strings.Contains(arg, "-test.coverprofile") {
+			out = append(out, arg)
+		}
+	}
+	return
+}
+
+// redefine all the flags otherwise the go testing tool
+// is not able to parse them ...
+var _ = flag.Int("db-open-attempts", 10, "number of attempts to open DB if it's locked by other instance")
+var _ = flag.Bool("dep-follow-suggests", false, "when processing dependencies, follow Suggests")
+var _ = flag.Bool("dep-follow-source", false, "when processing dependencies, follow from binary to Source packages")
+var _ = flag.Bool("dep-follow-recommends", false, "when processing dependencies, follow Recommends")
+var _ = flag.Bool("dep-follow-all-variants", false, "when processing dependencies, follow a & b if dependency is 'a|b'")
+var _ = flag.Bool("dep-verbose-resolve", false, "when processing dependencies, print detailed logs")
+var _ = flag.String("architectures", "", "list of architectures to consider during (comma-separated), default to all available")
+var _ = flag.String("config", "", "location of configuration file (default locations are /etc/aptly.conf, ~/.aptly.conf)")
+var _ = flag.String("gpg-provider", "", "PGP implementation (\"gpg\", \"gpg1\", \"gpg2\" for external gpg or \"internal\" for Go internal implementation)")
+
+var _ = flag.String("cpuprofile", "", "write cpu profile to file")
+var _ = flag.String("memprofile", "", "write memory profile to this file")
+var _ = flag.String("memstats", "", "write memory stats periodically to this file")
+var _ = flag.Duration("meminterval", 100*time.Millisecond, "memory stats dump interval")
+
+var _ = flag.Bool("raw", false, "raw")
+var _ = flag.String("sort", "false", "sort")
+var _ = flag.Bool("json", false, "json")
+
+func TestRunMain(t *testing.T) {
+	if Version == "" {
+		Version = "unknown"
+	}
+
+	aptly.Version = Version
+
+	rand.Seed(time.Now().UnixNano())
+
+	args := filterOutTestArgs(os.Args[1:])
+	root := cmd.RootCommand()
+	root.UsageLine = "aptly"
+
+	fmt.Printf("EXIT: %d\n", cmd.Run(root, args, true))
+}