Merge pull request #330 from pohly/copy-to-go-flagset

implement CopyToGoFlagSet

1 files changed, 74 insertions, 0 deletions

diff --git a/golangflag_test.go b/golangflag_test.go
index 2ecefef..7309808 100644
--- a/golangflag_test.go
+++ b/golangflag_test.go
@@ -7,6 +7,7 @@ package pflag
 import (
 	goflag "flag"
 	"testing"
+	"time"
 )
 
 func TestGoflags(t *testing.T) {
@@ -59,3 +60,76 @@ func TestGoflags(t *testing.T) {
 		t.Fatal("goflag.CommandLine.Parsed() return false after f.Parse() called")
 	}
 }
+
+func TestToGoflags(t *testing.T) {
+	pfs := FlagSet{}
+	gfs := goflag.FlagSet{}
+	pfs.String("StringFlag", "String value", "String flag usage")
+	pfs.Int("IntFlag", 1, "Int flag usage")
+	pfs.Uint("UintFlag", 2, "Uint flag usage")
+	pfs.Int64("Int64Flag", 3, "Int64 flag usage")
+	pfs.Uint64("Uint64Flag", 4, "Uint64 flag usage")
+	pfs.Int8("Int8Flag", 5, "Int8 flag usage")
+	pfs.Float64("Float64Flag", 6.0, "Float64 flag usage")
+	pfs.Duration("DurationFlag", time.Second, "Duration flag usage")
+	pfs.Bool("BoolFlag", true, "Bool flag usage")
+	pfs.String("deprecated", "Deprecated value", "Deprecated flag usage")
+	pfs.MarkDeprecated("deprecated", "obsolete")
+
+	pfs.CopyToGoFlagSet(&gfs)
+
+	// Modify via pfs. Should be visible via gfs because both share the
+	// same values.
+	for name, value := range map[string]string{
+		"StringFlag":  "Modified String value",
+		"IntFlag":     "11",
+		"UintFlag":    "12",
+		"Int64Flag":   "13",
+		"Uint64Flag":  "14",
+		"Int8Flag":    "15",
+		"Float64Flag": "16.0",
+		"BoolFlag":    "false",
+	} {
+		pf := pfs.Lookup(name)
+		if pf == nil {
+			t.Errorf("%s: not found in pflag flag set", name)
+			continue
+		}
+		if err := pf.Value.Set(value); err != nil {
+			t.Errorf("error setting %s = %s: %v", name, value, err)
+		}
+	}
+
+	// Check that all flags were added and share the same value.
+	pfs.VisitAll(func(pf *Flag) {
+		gf := gfs.Lookup(pf.Name)
+		if gf == nil {
+			t.Errorf("%s: not found in Go flag set", pf.Name)
+			return
+		}
+		if gf.Value.String() != pf.Value.String() {
+			t.Errorf("%s: expected value %v from Go flag set, got %v",
+				pf.Name, pf.Value, gf.Value)
+			return
+		}
+	})
+
+	// Check for unexpected additional flags.
+	gfs.VisitAll(func(gf *goflag.Flag) {
+		pf := gfs.Lookup(gf.Name)
+		if pf == nil {
+			t.Errorf("%s: not found in pflag flag set", gf.Name)
+			return
+		}
+	})
+
+	deprecated := gfs.Lookup("deprecated")
+	if deprecated == nil {
+		t.Error("deprecated: not found in Go flag set")
+	} else {
+		expectedUsage := "Deprecated flag usage (DEPRECATED: obsolete)"
+		if deprecated.Usage != expectedUsage {
+			t.Errorf("deprecation remark not added, expected usage %q, got %q", expectedUsage, deprecated.Usage)
+		}
+	}
+}