Add fl_value_equal_string()

For comparing an FlValue to a string (constant) without having to
allocate another FlValue just for the comparison. This helps to fix a
memory leak in FlTextInputPlugin.

Author: jpnurmi

shell/platform/linux/fl_value.cc

@@ -503,6 +503,15 @@ G_MODULE_EXPORT bool fl_value_equal(FlValue* a, FlValue* b) {
   }
 }
 
+G_MODULE_EXPORT bool fl_value_equal_string(FlValue* self, const gchar* value) {
+  g_return_val_if_fail(self != nullptr, false);
+  g_return_val_if_fail(value != nullptr, false);
+  g_return_val_if_fail(self->type == FL_VALUE_TYPE_STRING, false);
+
+  FlValueString* str_ = reinterpret_cast<FlValueString*>(self);
+  return g_strcmp0(str_->value, value) == 0;
+}
+
 G_MODULE_EXPORT void fl_value_append(FlValue* self, FlValue* value) {
   g_return_if_fail(self != nullptr);
   g_return_if_fail(self->type == FL_VALUE_TYPE_LIST);

shell/platform/linux/fl_value_test.cc

@@ -185,12 +185,16 @@ TEST(FlValueTest, StringEqual) {
   g_autoptr(FlValue) value1 = fl_value_new_string("hello");
   g_autoptr(FlValue) value2 = fl_value_new_string("hello");
   EXPECT_TRUE(fl_value_equal(value1, value2));
+  EXPECT_TRUE(fl_value_equal_string(value1, "hello"));
+  EXPECT_TRUE(fl_value_equal_string(value2, "hello"));
 }
 
 TEST(FlValueTest, StringNotEqual) {
   g_autoptr(FlValue) value1 = fl_value_new_string("hello");
   g_autoptr(FlValue) value2 = fl_value_new_string("world");
   EXPECT_FALSE(fl_value_equal(value1, value2));
+  EXPECT_FALSE(fl_value_equal_string(value1, "world"));
+  EXPECT_FALSE(fl_value_equal_string(value2, "hello"));
 }
 
 TEST(FlValueTest, StringToString) {

shell/platform/linux/public/flutter_linux/fl_value.h

@@ -312,6 +312,19 @@ FlValueType fl_value_get_type(FlValue* value);
  */
 bool fl_value_equal(FlValue* a, FlValue* b);
 
+/**
+ * fl_value_equal_string:
+ * @value: an #FlValue.
+ * @string: a %NULL-terminated UTF-8 string.
+ *
+ * Compares an #FlValue to a @string to see if they are equivalent. Calling
+ * this with an #FlValue that is not of type #FL_VALUE_TYPE_STRING is a
+ * programming error.
+ *
+ * Returns: %TRUE if the strings are equivalent.
+ */
+bool fl_value_equal_string(FlValue* value, const gchar* string);
+
 /**
  * fl_value_append:
  * @value: an #FlValue of type #FL_VALUE_TYPE_LIST.