internal/uevent: kobject_action lookup

This is encoded as part of kobject uevent message headers.

Signed-off-by: Ophestra <cat@gensokyo.uk>

internal/uevent/uevent_test.go

@@ -0,0 +1,83 @@
+package uevent_test
+
+import (
+	"encoding"
+	"fmt"
+	"reflect"
+	"testing"
+
+	"hakurei.app/internal/uevent"
+)
+
+// adeT sets up a parallel subtest for a textual appender/decoder/encoder.
+func adeT[V any, S interface {
+	encoding.TextAppender
+	encoding.TextMarshaler
+	encoding.TextUnmarshaler
+	fmt.Stringer
+
+	*V
+}](t *testing.T, name string, v V, want string, wantErr, wantErrE error) {
+	t.Helper()
+	t.Run(name, func(t *testing.T) {
+		t.Parallel()
+		t.Helper()
+
+		t.Run("decode", func(t *testing.T) {
+			t.Parallel()
+			t.Helper()
+
+			var got V
+			if err := S(&got).UnmarshalText([]byte(want)); !reflect.DeepEqual(err, wantErr) {
+				t.Fatalf("UnmarshalText: error = %v, want %v", err, wantErr)
+			}
+			if wantErr != nil {
+				return
+			}
+
+			if !reflect.DeepEqual(&got, &v) {
+				t.Errorf("UnmarshalText: %#v, want %#v", got, v)
+			}
+		})
+
+		t.Run("encode", func(t *testing.T) {
+			t.Parallel()
+			t.Helper()
+
+			if got, err := S(&v).MarshalText(); !reflect.DeepEqual(err, wantErrE) {
+				t.Fatalf("MarshalText: error = %v, want %v", err, wantErrE)
+			} else if err == nil && string(got) != want {
+				t.Errorf("MarshalText: %q, want %q", string(got), want)
+			}
+			if wantErrE != nil {
+				return
+			}
+
+			if got := S(&v).String(); got != want {
+				t.Errorf("String: %q, want %q", got, want)
+			}
+		})
+	})
+}
+
+func TestErrors(t *testing.T) {
+	t.Parallel()
+
+	testCases := []struct {
+		name string
+		err  error
+		want string
+	}{
+		{"UnsupportedActionError", uevent.UnsupportedActionError("explode"),
+			`unsupported kobject_action "explode"`},
+	}
+	for _, tc := range testCases {
+		t.Run(tc.name, func(t *testing.T) {
+			t.Parallel()
+
+			if got := tc.err.Error(); got != tc.want {
+				t.Errorf("Error: %q, want %q", got, tc.want)
+			}
+		})
+	}
+}