team-humaki · Sep 17, 2026
diff --git a/ini.go b/ini.go
@@ -125,6 +125,10 @@ type LoadOptions struct {
 	AllowNonUniqueSections bool
 	// AllowDuplicateShadowValues indicates whether values for shadowed keys should be deduplicated.
 	AllowDuplicateShadowValues bool
+	// PreserveEmptyShadows indicates whether ValueWithShadows should keep empty
+	// assignments. Empty values are otherwise omitted (the historical default).
+	// systemd unit files use an empty assignment to reset prior values.
+	PreserveEmptyShadows bool
 }
 
 // DebugFunc is the type of function called to log parse events.

diff --git a/key.go b/key.go
@@ -110,22 +110,23 @@ func (k *Key) Value() string {
 	return k.value
 }
 
-// ValueWithShadows returns raw values of key and its shadows if any. Shadow
-// keys with empty values are ignored from the returned list.
+// ValueWithShadows returns raw values of key and its shadows if any.
+// Empty values are omitted unless LoadOptions.PreserveEmptyShadows is set.
 func (k *Key) ValueWithShadows() []string {
+	keepEmpty := k.s != nil && k.s.f != nil && k.s.f.options.PreserveEmptyShadows
 	if len(k.shadows) == 0 {
-		if k.value == "" {
+		if k.value == "" && !keepEmpty {
 			return []string{}
 		}
 		return []string{k.value}
 	}
 
 	vals := make([]string, 0, len(k.shadows)+1)
-	if k.value != "" {
+	if k.value != "" || keepEmpty {
 		vals = append(vals, k.value)
 	}
 	for _, s := range k.shadows {
-		if s.value != "" {
+		if s.value != "" || keepEmpty {
 			vals = append(vals, s.value)
 		}
 	}

diff --git a/key_test.go b/key_test.go
@@ -66,6 +66,20 @@ func TestKey_AddShadow(t *testing.T) {
 		})
 	})
 
+	t.Run("preserve empty shadow values", func(t *testing.T) {
+		f := Empty(LoadOptions{
+			AllowShadows:         true,
+			PreserveEmptyShadows: true,
+		})
+		require.NotNil(t, f)
+
+		k, err := f.Section("").NewKey("Environment", "FOO=bar")
+		require.NoError(t, err)
+		require.NotNil(t, k)
+		assert.NoError(t, k.AddShadow(""))
+		assert.Equal(t, []string{"FOO=bar", ""}, k.ValueWithShadows())
+	})
+
 	t.Run("allow duplicate shadowed values", func(t *testing.T) {
 		f := Empty(LoadOptions{
 			AllowShadows:               true,
@@ -546,6 +560,31 @@ keyName = value2
 		require.NotNil(t, k)
 		assert.Equal(t, []string{"value1", "value2"}, k.ValueWithShadows())
 	})
+
+	t.Run("preserve empty assignments from file", func(t *testing.T) {
+		f, err := LoadSources(LoadOptions{
+			AllowShadows:         true,
+			PreserveEmptyShadows: true,
+		}, []byte(`
+[Service]
+Environment=FOO=bar
+Environment=
+`))
+		require.NoError(t, err)
+		require.NotNil(t, f)
+		assert.Equal(t, []string{"FOO=bar", ""}, f.Section("Service").Key("Environment").ValueWithShadows())
+	})
+
+	t.Run("default still drops empty assignments from file", func(t *testing.T) {
+		f, err := ShadowLoad([]byte(`
+[Service]
+Environment=FOO=bar
+Environment=
+`))
+		require.NoError(t, err)
+		require.NotNil(t, f)
+		assert.Equal(t, []string{"FOO=bar"}, f.Section("Service").Key("Environment").ValueWithShadows())
+	})
 }
 
 func TestKey_StringsWithShadows(t *testing.T) {