Replace String comparisons with "", String() to is_empty()

Also:
- Adds two stress tests to test_string.h
- Changes to .empty() on std::strings

10 files changed, 84 insertions, 84 deletions

diff --git a/scene/resources/importer_mesh.cpp b/scene/resources/importer_mesh.cpp
index 7afa4c91f0..604b9e359f 100644
--- a/scene/resources/importer_mesh.cpp
+++ b/scene/resources/importer_mesh.cpp
@@ -653,7 +653,7 @@ Ref<ArrayMesh> ImporterMesh::get_mesh(const Ref<ArrayMesh> &p_base) {
 			if (surfaces[i].material.is_valid()) {
 				mesh->surface_set_material(mesh->get_surface_count() - 1, surfaces[i].material);
 			}
-			if (surfaces[i].name != String()) {
+			if (!surfaces[i].name.is_empty()) {
 				mesh->surface_set_name(mesh->get_surface_count() - 1, surfaces[i].name);
 			}
 		}
@@ -839,7 +839,7 @@ Dictionary ImporterMesh::_get_data() const {
 			d["material"] = surfaces[i].material;
 		}
 
-		if (surfaces[i].name != String()) {
+		if (!surfaces[i].name.is_empty()) {
 			d["name"] = surfaces[i].name;
 		}
 
diff --git a/scene/resources/mesh.cpp b/scene/resources/mesh.cpp
index e14d6be235..bd63d17424 100644
--- a/scene/resources/mesh.cpp
+++ b/scene/resources/mesh.cpp
@@ -1104,7 +1104,7 @@ Array ArrayMesh::_get_surfaces() const {
 			data["material"] = surfaces[i].material;
 		}
 
-		if (surfaces[i].name != String()) {
+		if (!surfaces[i].name.is_empty()) {
 			data["name"] = surfaces[i].name;
 		}
 
diff --git a/scene/resources/packed_scene.cpp b/scene/resources/packed_scene.cpp
index c39f59d535..e6b499d4f1 100644
--- a/scene/resources/packed_scene.cpp
+++ b/scene/resources/packed_scene.cpp
@@ -417,7 +417,7 @@ Error SceneState::_parse_node(Node *p_owner, Node *p_node, int p_parent_idx, Map
 
 	// save the child instantiated scenes that are chosen as editable, so they can be restored
 	// upon load back
-	if (p_node != p_owner && p_node->get_scene_file_path() != String() && p_owner->is_editable_instance(p_node)) {
+	if (p_node != p_owner && !p_node->get_scene_file_path().is_empty() && p_owner->is_editable_instance(p_node)) {
 		editable_instances.push_back(p_owner->get_path_to(p_node));
 		// Node is the root of an editable instance.
 		is_editable_instance = true;
@@ -451,7 +451,7 @@ Error SceneState::_parse_node(Node *p_owner, Node *p_node, int p_parent_idx, Map
 	bool instantiated_by_owner = false;
 	Vector<SceneState::PackState> states_stack = PropertyUtils::get_node_states_stack(p_node, p_owner, &instantiated_by_owner);
 
-	if (p_node->get_scene_file_path() != String() && p_node->get_owner() == p_owner && instantiated_by_owner) {
+	if (!p_node->get_scene_file_path().is_empty() && p_node->get_owner() == p_owner && instantiated_by_owner) {
 		if (p_node->get_scene_instance_load_placeholder()) {
 			//it's a placeholder, use the placeholder path
 			nd.instance = _vm_get_variant(p_node->get_scene_file_path(), variant_map);
@@ -656,7 +656,7 @@ Error SceneState::_parse_connections(Node *p_owner, Node *p_node, Map<StringName
 
 			ERR_CONTINUE(!common_parent);
 
-			if (common_parent != p_owner && common_parent->get_scene_file_path() == String()) {
+			if (common_parent != p_owner && common_parent->get_scene_file_path().is_empty()) {
 				common_parent = common_parent->get_owner();
 			}
 
@@ -716,7 +716,7 @@ Error SceneState::_parse_connections(Node *p_owner, Node *p_node, Map<StringName
 
 						nl = nullptr;
 					} else {
-						if (nl->get_scene_file_path() != String()) {
+						if (!nl->get_scene_file_path().is_empty()) {
 							//is an instance
 							Ref<SceneState> state = nl->get_scene_instance_state();
 							if (state.is_valid()) {
diff --git a/scene/resources/resource_format_text.cpp b/scene/resources/resource_format_text.cpp
index cead42b4e2..0e354ebff4 100644
--- a/scene/resources/resource_format_text.cpp
+++ b/scene/resources/resource_format_text.cpp
@@ -274,12 +274,12 @@ Ref<PackedScene> ResourceLoaderText::_parse_node_tag(VariantParser::ResourcePars
 					}
 				}
 
-				if (assign != String()) {
+				if (!assign.is_empty()) {
 					int nameidx = packed_scene->get_state()->add_name(assign);
 					int valueidx = packed_scene->get_state()->add_value(value);
 					packed_scene->get_state()->add_node_property(node_id, nameidx, valueidx);
 					//it's assignment
-				} else if (next_tag.name != String()) {
+				} else if (!next_tag.name.is_empty()) {
 					break;
 				}
 			}
@@ -575,12 +575,12 @@ Error ResourceLoaderText::load() {
 				return error;
 			}
 
-			if (assign != String()) {
+			if (!assign.is_empty()) {
 				if (do_assign) {
 					res->set(assign, value);
 				}
 				//it's assignment
-			} else if (next_tag.name != String()) {
+			} else if (!next_tag.name.is_empty()) {
 				error = OK;
 				break;
 			} else {
@@ -659,10 +659,10 @@ Error ResourceLoaderText::load() {
 				return error;
 			}
 
-			if (assign != String()) {
+			if (!assign.is_empty()) {
 				resource->set(assign, value);
 				//it's assignment
-			} else if (next_tag.name != String()) {
+			} else if (!next_tag.name.is_empty()) {
 				error = ERR_FILE_CORRUPT;
 				error_text = "Extra tag found when parsing main resource file";
 				_printerr();
@@ -1166,13 +1166,13 @@ Error ResourceLoaderText::save_as_binary(FileAccess *p_f, const String &p_path)
 				return error;
 			}
 
-			if (assign != String()) {
+			if (!assign.is_empty()) {
 				Map<StringName, int> empty_string_map; //unused
 				bs_save_unicode_string(wf2, assign, true);
 				ResourceFormatSaverBinaryInstance::write_variant(wf2, value, dummy_read.resource_index_map, dummy_read.external_resources, empty_string_map);
 				prop_count++;
 
-			} else if (next_tag.name != String()) {
+			} else if (!next_tag.name.is_empty()) {
 				error = OK;
 				break;
 			} else {
@@ -1350,7 +1350,7 @@ RES ResourceFormatLoaderText::load(const String &p_path, const String &p_origina
 	ERR_FAIL_COND_V_MSG(err != OK, RES(), "Cannot open file '" + p_path + "'.");
 
 	ResourceLoaderText loader;
-	String path = p_original_path != "" ? p_original_path : p_path;
+	String path = !p_original_path.is_empty() ? p_original_path : p_path;
 	loader.cache_mode = p_cache_mode;
 	loader.use_sub_threads = p_use_sub_threads;
 	loader.local_path = ProjectSettings::get_singleton()->localize_path(path);
@@ -1369,7 +1369,7 @@ RES ResourceFormatLoaderText::load(const String &p_path, const String &p_origina
 }
 
 void ResourceFormatLoaderText::get_recognized_extensions_for_type(const String &p_type, List<String> *p_extensions) const {
-	if (p_type == "") {
+	if (p_type.is_empty()) {
 		get_recognized_extensions(p_extensions);
 		return;
 	}
@@ -1655,7 +1655,7 @@ Error ResourceFormatSaverTextInstance::save(const String &p_path, const RES &p_r
 	Set<String> cached_ids_found;
 	for (KeyValue<RES, String> &E : external_resources) {
 		String cached_id = E.key->get_id_for_path(local_path);
-		if (cached_id == "" || cached_ids_found.has(cached_id)) {
+		if (cached_id.is_empty() || cached_ids_found.has(cached_id)) {
 			int sep_pos = E.value.find("_");
 			if (sep_pos != -1) {
 				E.value = E.value.substr(0, sep_pos + 1); // Keep the order found, for improved thread loading performance.
@@ -1729,7 +1729,7 @@ Error ResourceFormatSaverTextInstance::save(const String &p_path, const RES &p_r
 	for (List<RES>::Element *E = saved_resources.front(); E; E = E->next()) {
 		RES res = E->get();
 		if (E->next() && res->is_built_in()) {
-			if (res->get_scene_unique_id() != "") {
+			if (!res->get_scene_unique_id().is_empty()) {
 				if (used_unique_ids.has(res->get_scene_unique_id())) {
 					res->set_scene_unique_id(""); // Repeated.
 				} else {
@@ -1752,7 +1752,7 @@ Error ResourceFormatSaverTextInstance::save(const String &p_path, const RES &p_r
 			f->store_line("[resource]");
 		} else {
 			String line = "[sub_resource ";
-			if (res->get_scene_unique_id() == "") {
+			if (res->get_scene_unique_id().is_empty()) {
 				String new_id;
 				while (true) {
 					new_id = res->get_class() + "_" + Resource::generate_scene_unique_id();
@@ -1866,7 +1866,7 @@ Error ResourceFormatSaverTextInstance::save(const String &p_path, const RES &p_r
 
 			f->store_string(header);
 
-			if (instance_placeholder != String()) {
+			if (!instance_placeholder.is_empty()) {
 				String vars;
 				f->store_string(" instance_placeholder=");
 				VariantWriter::write_to_string(instance_placeholder, vars, _write_resources, this);
diff --git a/scene/resources/syntax_highlighter.cpp b/scene/resources/syntax_highlighter.cpp
index cfb5ac2ca6..800752d597 100644
--- a/scene/resources/syntax_highlighter.cpp
+++ b/scene/resources/syntax_highlighter.cpp
@@ -493,7 +493,7 @@ void CodeHighlighter::add_color_region(const String &p_start_key, const String &
 	color_region.color = p_color;
 	color_region.start_key = p_start_key;
 	color_region.end_key = p_end_key;
-	color_region.line_only = p_line_only || p_end_key == "";
+	color_region.line_only = p_line_only || p_end_key.is_empty();
 	color_regions.insert(at, color_region);
 	clear_highlighting_cache();
 }
@@ -529,7 +529,7 @@ void CodeHighlighter::set_color_regions(const Dictionary &p_color_regions) {
 		String start_key = key.get_slice(" ", 0);
 		String end_key = key.get_slice_count(" ") > 1 ? key.get_slice(" ", 1) : String();
 
-		add_color_region(start_key, end_key, p_color_regions[key], end_key == "");
+		add_color_region(start_key, end_key, p_color_regions[key], end_key.is_empty());
 	}
 	clear_highlighting_cache();
 }
diff --git a/scene/resources/text_file.cpp b/scene/resources/text_file.cpp
index 33bb0a83e9..1dc46711f8 100644
--- a/scene/resources/text_file.cpp
+++ b/scene/resources/text_file.cpp
@@ -33,7 +33,7 @@
 #include "core/io/file_access.h"
 
 bool TextFile::has_text() const {
-	return text != "";
+	return !text.is_empty();
 }
 
 String TextFile::get_text() const {
diff --git a/scene/resources/texture.cpp b/scene/resources/texture.cpp
index 311bd9524b..13c3f6ea1d 100644
--- a/scene/resources/texture.cpp
+++ b/scene/resources/texture.cpp
@@ -553,7 +553,7 @@ Error StreamTexture2D::load(const String &p_path) {
 	path_to_file = p_path;
 	format = image->get_format();
 
-	if (get_path() == String()) {
+	if (get_path().is_empty()) {
 		//temporarily set path if no path set for resource, helps find errors
 		RenderingServer::get_singleton()->texture_set_path(texture, p_path);
 	}
@@ -927,7 +927,7 @@ Error StreamTexture3D::load(const String &p_path) {
 
 	path_to_file = p_path;
 
-	if (get_path() == String()) {
+	if (get_path().is_empty()) {
 		//temporarily set path if no path set for resource, helps find errors
 		RenderingServer::get_singleton()->texture_set_path(texture, p_path);
 	}
@@ -2680,7 +2680,7 @@ Error StreamTextureLayered::load(const String &p_path) {
 
 	path_to_file = p_path;
 
-	if (get_path() == String()) {
+	if (get_path().is_empty()) {
 		//temporarily set path if no path set for resource, helps find errors
 		RenderingServer::get_singleton()->texture_set_path(texture, p_path);
 	}
diff --git a/scene/resources/visual_shader.cpp b/scene/resources/visual_shader.cpp
index 41e78e0bc8..10e75fb023 100644
--- a/scene/resources/visual_shader.cpp
+++ b/scene/resources/visual_shader.cpp
@@ -979,7 +979,7 @@ String VisualShader::generate_preview_shader(Type p_type, int p_node, int p_port
 String VisualShader::validate_port_name(const String &p_port_name, VisualShaderNode *p_node, int p_port_id, bool p_output) const {
 	String name = p_port_name;
 
-	if (name == String()) {
+	if (name.is_empty()) {
 		return String();
 	}
 
@@ -987,7 +987,7 @@ String VisualShader::validate_port_name(const String &p_port_name, VisualShaderN
 		name = name.substr(1, name.length() - 1);
 	}
 
-	if (name != String()) {
+	if (!name.is_empty()) {
 		String valid_name;
 
 		for (int i = 0; i < name.length(); i++) {
@@ -1031,7 +1031,7 @@ String VisualShader::validate_uniform_name(const String &p_name, const Ref<Visua
 	while (name.length() && !IS_INITIAL_CHAR(name[0])) {
 		name = name.substr(1, name.length() - 1);
 	}
-	if (name != String()) {
+	if (!name.is_empty()) {
 		String valid_name;
 
 		for (int i = 0; i < name.length(); i++) {
@@ -1045,7 +1045,7 @@ String VisualShader::validate_uniform_name(const String &p_name, const Ref<Visua
 		name = valid_name;
 	}
 
-	if (name == String()) {
+	if (name.is_empty()) {
 		name = p_uniform->get_caption();
 	}
 
@@ -1075,7 +1075,7 @@ String VisualShader::validate_uniform_name(const String &p_name, const Ref<Visua
 			while (name.length() && name[name.length() - 1] >= '0' && name[name.length() - 1] <= '9') {
 				name = name.substr(0, name.length() - 1);
 			}
-			ERR_FAIL_COND_V(name == String(), String());
+			ERR_FAIL_COND_V(name.is_empty(), String());
 			name += itos(attempt);
 		} else {
 			break;
@@ -1568,7 +1568,7 @@ Error VisualShader::_write_node(Type type, StringBuilder &global_code, StringBui
 	}
 
 	node_code += vsnode->generate_code(get_mode(), type, node, inputs, outputs, for_preview);
-	if (node_code != String()) {
+	if (!node_code.is_empty()) {
 		code += node_name;
 		code += node_code;
 		code += "\n";
@@ -1664,7 +1664,7 @@ void VisualShader::_update_shader() const {
 						String mode = ShaderTypes::get_singleton()->get_modes(RenderingServer::ShaderMode(shader_mode))[i];
 						if (mode.begins_with(render_mode_enums[idx].string)) {
 							if (count == which) {
-								if (render_mode != String()) {
+								if (!render_mode.is_empty()) {
 									render_mode += ", ";
 								}
 								render_mode += mode;
@@ -1682,7 +1682,7 @@ void VisualShader::_update_shader() const {
 		for (int i = 0; i < ShaderTypes::get_singleton()->get_modes(RenderingServer::ShaderMode(shader_mode)).size(); i++) {
 			String mode = ShaderTypes::get_singleton()->get_modes(RenderingServer::ShaderMode(shader_mode))[i];
 			if (flags.has(mode)) {
-				if (render_mode != String()) {
+				if (!render_mode.is_empty()) {
 					render_mode += ", ";
 				}
 				render_mode += mode;
@@ -1690,7 +1690,7 @@ void VisualShader::_update_shader() const {
 		}
 	}
 
-	if (render_mode != String()) {
+	if (!render_mode.is_empty()) {
 		global_code += "render_mode " + render_mode + ";\n\n";
 	}
 
@@ -2468,7 +2468,7 @@ String VisualShaderNodeInput::generate_code(Shader::Mode p_mode, VisualShader::T
 			idx++;
 		}
 
-		if (code == String()) {
+		if (code.is_empty()) {
 			switch (get_output_port_type(0)) {
 				case PORT_TYPE_SCALAR: {
 					code = "	" + p_output_vars[0] + " = 0.0;\n";
@@ -2502,7 +2502,7 @@ String VisualShaderNodeInput::generate_code(Shader::Mode p_mode, VisualShader::T
 			idx++;
 		}
 
-		if (code == String()) {
+		if (code.is_empty()) {
 			code = "	" + p_output_vars[0] + " = 0.0;\n"; //default (none found) is scalar
 		}
 
@@ -2605,7 +2605,7 @@ void VisualShaderNodeInput::_validate_property(PropertyInfo &property) const {
 
 		while (ports[idx].mode != Shader::MODE_MAX) {
 			if (ports[idx].mode == shader_mode && ports[idx].shader_type == shader_type) {
-				if (port_list != String()) {
+				if (!port_list.is_empty()) {
 					port_list += ",";
 				}
 				port_list += ports[idx].name;
@@ -2613,7 +2613,7 @@ void VisualShaderNodeInput::_validate_property(PropertyInfo &property) const {
 			idx++;
 		}
 
-		if (port_list == "") {
+		if (port_list.is_empty()) {
 			port_list = TTR("None");
 		}
 		property.hint_string = port_list;
@@ -3063,7 +3063,7 @@ String VisualShaderNodeOutput::generate_code(Shader::Mode p_mode, VisualShader::
 	String code;
 	while (ports[idx].mode != Shader::MODE_MAX) {
 		if (ports[idx].mode == shader_mode && ports[idx].shader_type == shader_type) {
-			if (p_input_vars[count] != String()) {
+			if (!p_input_vars[count].is_empty()) {
 				String s = ports[idx].string;
 				if (s.find(":") != -1) {
 					code += "	" + s.get_slicec(':', 0) + " = " + p_input_vars[count] + "." + s.get_slicec(':', 1) + ";\n";
diff --git a/scene/resources/visual_shader_nodes.cpp b/scene/resources/visual_shader_nodes.cpp
index e6870971d4..51e7ec8092 100644
--- a/scene/resources/visual_shader_nodes.cpp
+++ b/scene/resources/visual_shader_nodes.cpp
@@ -535,15 +535,15 @@ String VisualShaderNodeTexture::generate_code(Shader::Mode p_mode, VisualShader:
 	if (source == SOURCE_TEXTURE) {
 		String id = make_unique_id(p_type, p_id, "tex");
 		String code;
-		if (p_input_vars[0] == String()) { // Use UV by default.
+		if (p_input_vars[0].is_empty()) { // Use UV by default.
 
-			if (p_input_vars[1] == String()) {
+			if (p_input_vars[1].is_empty()) {
 				code += "	vec4 " + id + "_read = texture(" + id + ", " + default_uv + ");\n";
 			} else {
 				code += "	vec4 " + id + "_read = textureLod(" + id + ", " + default_uv + ", " + p_input_vars[1] + ");\n";
 			}
 
-		} else if (p_input_vars[1] == String()) {
+		} else if (p_input_vars[1].is_empty()) {
 			//no lod
 			code += "	vec4 " + id + "_read = texture(" + id + ", " + p_input_vars[0] + ".xy);\n";
 		} else {
@@ -560,18 +560,18 @@ String VisualShaderNodeTexture::generate_code(Shader::Mode p_mode, VisualShader:
 
 		String code;
 		code += "	{\n";
-		if (id == String()) {
+		if (id.is_empty()) {
 			code += "		vec4 " + id + "_tex_read = vec4(0.0);\n";
 		} else {
-			if (p_input_vars[0] == String()) { // Use UV by default.
+			if (p_input_vars[0].is_empty()) { // Use UV by default.
 
-				if (p_input_vars[1] == String()) {
+				if (p_input_vars[1].is_empty()) {
 					code += "		vec4 " + id + "_tex_read = texture(" + id + ", " + default_uv + ");\n";
 				} else {
 					code += "		vec4 " + id + "_tex_read = textureLod(" + id + ", " + default_uv + ", " + p_input_vars[1] + ");\n";
 				}
 
-			} else if (p_input_vars[1] == String()) {
+			} else if (p_input_vars[1].is_empty()) {
 				//no lod
 				code += "		vec4 " + id + "_tex_read = texture(" + id + ", " + p_input_vars[0] + ".xy);\n";
 			} else {
@@ -587,15 +587,15 @@ String VisualShaderNodeTexture::generate_code(Shader::Mode p_mode, VisualShader:
 
 	if (source == SOURCE_SCREEN && (p_mode == Shader::MODE_SPATIAL || p_mode == Shader::MODE_CANVAS_ITEM) && p_type == VisualShader::TYPE_FRAGMENT) {
 		String code = "	{\n";
-		if (p_input_vars[0] == String() || p_for_preview) { // Use UV by default.
+		if (p_input_vars[0].is_empty() || p_for_preview) { // Use UV by default.
 
-			if (p_input_vars[1] == String()) {
+			if (p_input_vars[1].is_empty()) {
 				code += "		vec4 _tex_read = textureLod(SCREEN_TEXTURE, " + default_uv + ", 0.0 );\n";
 			} else {
 				code += "		vec4 _tex_read = textureLod(SCREEN_TEXTURE, " + default_uv + ", " + p_input_vars[1] + ");\n";
 			}
 
-		} else if (p_input_vars[1] == String()) {
+		} else if (p_input_vars[1].is_empty()) {
 			//no lod
 			code += "		vec4 _tex_read = textureLod(SCREEN_TEXTURE, " + p_input_vars[0] + ".xy, 0.0);\n";
 		} else {
@@ -610,15 +610,15 @@ String VisualShaderNodeTexture::generate_code(Shader::Mode p_mode, VisualShader:
 
 	if (source == SOURCE_2D_TEXTURE && p_mode == Shader::MODE_CANVAS_ITEM && p_type == VisualShader::TYPE_FRAGMENT) {
 		String code = "	{\n";
-		if (p_input_vars[0] == String()) { // Use UV by default.
+		if (p_input_vars[0].is_empty()) { // Use UV by default.
 
-			if (p_input_vars[1] == String()) {
+			if (p_input_vars[1].is_empty()) {
 				code += "		vec4 _tex_read = texture(TEXTURE, " + default_uv + ");\n";
 			} else {
 				code += "		vec4 _tex_read = textureLod(TEXTURE, " + default_uv + ", " + p_input_vars[1] + ");\n";
 			}
 
-		} else if (p_input_vars[1] == String()) {
+		} else if (p_input_vars[1].is_empty()) {
 			//no lod
 			code += "		vec4 _tex_read = texture(TEXTURE, " + p_input_vars[0] + ".xy);\n";
 		} else {
@@ -633,15 +633,15 @@ String VisualShaderNodeTexture::generate_code(Shader::Mode p_mode, VisualShader:
 
 	if (source == SOURCE_2D_NORMAL && p_mode == Shader::MODE_CANVAS_ITEM && p_type == VisualShader::TYPE_FRAGMENT) {
 		String code = "	{\n";
-		if (p_input_vars[0] == String()) { // Use UV by default.
+		if (p_input_vars[0].is_empty()) { // Use UV by default.
 
-			if (p_input_vars[1] == String()) {
+			if (p_input_vars[1].is_empty()) {
 				code += "		vec4 _tex_read = texture(NORMAL_TEXTURE, " + default_uv + ");\n";
 			} else {
 				code += "		vec4 _tex_read = textureLod(NORMAL_TEXTURE, " + default_uv + ", " + p_input_vars[1] + ");\n";
 			}
 
-		} else if (p_input_vars[1] == String()) {
+		} else if (p_input_vars[1].is_empty()) {
 			//no lod
 			code += "		vec4 _tex_read = texture(NORMAL_TEXTURE, " + p_input_vars[0] + ".xy);\n";
 		} else {
@@ -666,15 +666,15 @@ String VisualShaderNodeTexture::generate_code(Shader::Mode p_mode, VisualShader:
 
 	if (source == SOURCE_DEPTH && p_mode == Shader::MODE_SPATIAL && p_type == VisualShader::TYPE_FRAGMENT) {
 		String code = "	{\n";
-		if (p_input_vars[0] == String()) { // Use UV by default.
+		if (p_input_vars[0].is_empty()) { // Use UV by default.
 
-			if (p_input_vars[1] == String()) {
+			if (p_input_vars[1].is_empty()) {
 				code += "		float _depth = texture(DEPTH_TEXTURE, " + default_uv + ").r;\n";
 			} else {
 				code += "		float _depth = textureLod(DEPTH_TEXTURE, " + default_uv + ", " + p_input_vars[1] + ").r;\n";
 			}
 
-		} else if (p_input_vars[1] == String()) {
+		} else if (p_input_vars[1].is_empty()) {
 			//no lod
 			code += "		float _depth = texture(DEPTH_TEXTURE, " + p_input_vars[0] + ".xy).r;\n";
 		} else {
@@ -883,7 +883,7 @@ String VisualShaderNodeCurveTexture::generate_global(Shader::Mode p_mode, Visual
 }
 
 String VisualShaderNodeCurveTexture::generate_code(Shader::Mode p_mode, VisualShader::Type p_type, int p_id, const String *p_input_vars, const String *p_output_vars, bool p_for_preview) const {
-	if (p_input_vars[0] == String()) {
+	if (p_input_vars[0].is_empty()) {
 		return "	" + p_output_vars[0] + " = 0.0;\n";
 	}
 	String id = make_unique_id(p_type, p_id, "curve");
@@ -968,7 +968,7 @@ String VisualShaderNodeCurveXYZTexture::generate_global(Shader::Mode p_mode, Vis
 }
 
 String VisualShaderNodeCurveXYZTexture::generate_code(Shader::Mode p_mode, VisualShader::Type p_type, int p_id, const String *p_input_vars, const String *p_output_vars, bool p_for_preview) const {
-	if (p_input_vars[0] == String()) {
+	if (p_input_vars[0].is_empty()) {
 		return "	" + p_output_vars[0] + " = vec3(0.0);\n";
 	}
 	String id = make_unique_id(p_type, p_id, "curve3d");
@@ -1076,14 +1076,14 @@ String VisualShaderNodeSample3D::generate_code(Shader::Mode p_mode, VisualShader
 		} else {
 			id = p_input_vars[2];
 		}
-		if (id != String()) {
-			if (p_input_vars[0] == String()) { // Use UV by default.
-				if (p_input_vars[1] == String()) {
+		if (!id.is_empty()) {
+			if (p_input_vars[0].is_empty()) { // Use UV by default.
+				if (p_input_vars[1].is_empty()) {
 					code += "		vec4 " + id + "_tex_read = texture(" + id + ", " + default_uv + ");\n";
 				} else {
 					code += "		vec4 " + id + "_tex_read = textureLod(" + id + ", " + default_uv + ", " + p_input_vars[1] + ");\n";
 				}
-			} else if (p_input_vars[1] == String()) {
+			} else if (p_input_vars[1].is_empty()) {
 				//no lod
 				code += "		vec4 " + id + "_tex_read = texture(" + id + ", " + p_input_vars[0] + ");\n";
 			} else {
@@ -1364,7 +1364,7 @@ String VisualShaderNodeCubemap::generate_code(Shader::Mode p_mode, VisualShader:
 
 	code += "	{\n";
 
-	if (id == String()) {
+	if (id.is_empty()) {
 		code += "		vec4 " + id + "_read = vec4(0.0);\n";
 		code += "		" + p_output_vars[0] + " = " + id + "_read.rgb;\n";
 		code += "		" + p_output_vars[1] + " = " + id + "_read.a;\n";
@@ -1372,15 +1372,15 @@ String VisualShaderNodeCubemap::generate_code(Shader::Mode p_mode, VisualShader:
 		return code;
 	}
 
-	if (p_input_vars[0] == String()) { // Use UV by default.
+	if (p_input_vars[0].is_empty()) { // Use UV by default.
 
-		if (p_input_vars[1] == String()) {
+		if (p_input_vars[1].is_empty()) {
 			code += "		vec4 " + id + "_read = texture(" + id + ", " + default_uv + ");\n";
 		} else {
 			code += "		vec4 " + id + "_read = textureLod(" + id + ", " + default_uv + ", " + p_input_vars[1] + " );\n";
 		}
 
-	} else if (p_input_vars[1] == String()) {
+	} else if (p_input_vars[1].is_empty()) {
 		//no lod
 		code += "		vec4 " + id + "_read = texture(" + id + ", " + p_input_vars[0] + ");\n";
 	} else {
@@ -4902,13 +4902,13 @@ String VisualShaderNodeTextureUniform::generate_code(Shader::Mode p_mode, Visual
 
 	String id = get_uniform_name();
 	String code = "	{\n";
-	if (p_input_vars[0] == String()) { // Use UV by default.
-		if (p_input_vars[1] == String()) {
+	if (p_input_vars[0].is_empty()) { // Use UV by default.
+		if (p_input_vars[1].is_empty()) {
 			code += "		vec4 n_tex_read = texture(" + id + ", " + default_uv + ");\n";
 		} else {
 			code += "		vec4 n_tex_read = textureLod(" + id + ", " + default_uv + ", " + p_input_vars[1] + ");\n";
 		}
-	} else if (p_input_vars[1] == String()) {
+	} else if (p_input_vars[1].is_empty()) {
 		//no lod
 		code += "		vec4 n_tex_read = texture(" + id + ", " + p_input_vars[0] + ".xy);\n";
 	} else {
@@ -5070,11 +5070,11 @@ String VisualShaderNodeTextureUniformTriplanar::generate_code(Shader::Mode p_mod
 	String id = get_uniform_name();
 	String code = "	{\n";
 
-	if (p_input_vars[0] == String() && p_input_vars[1] == String()) {
+	if (p_input_vars[0].is_empty() && p_input_vars[1].is_empty()) {
 		code += "		vec4 n_tex_read = triplanar_texture(" + id + ", triplanar_power_normal, triplanar_pos);\n";
-	} else if (p_input_vars[0] != String() && p_input_vars[1] == String()) {
+	} else if (!p_input_vars[0].is_empty() && p_input_vars[1].is_empty()) {
 		code += "		vec4 n_tex_read = triplanar_texture(" + id + ", " + p_input_vars[0] + ", triplanar_pos);\n";
-	} else if (p_input_vars[0] == String() && p_input_vars[1] != String()) {
+	} else if (p_input_vars[0].is_empty() && !p_input_vars[1].is_empty()) {
 		code += "		vec4 n_tex_read = triplanar_texture(" + id + ", triplanar_power_normal, " + p_input_vars[1] + ");\n";
 	} else {
 		code += "		vec4 n_tex_read = triplanar_texture(" + id + ", " + p_input_vars[0] + ", " + p_input_vars[1] + ");\n";
@@ -5600,12 +5600,12 @@ bool VisualShaderNodeFresnel::is_generate_input_var(int p_port) const {
 String VisualShaderNodeFresnel::generate_code(Shader::Mode p_mode, VisualShader::Type p_type, int p_id, const String *p_input_vars, const String *p_output_vars, bool p_for_preview) const {
 	String normal;
 	String view;
-	if (p_input_vars[0] == String()) {
+	if (p_input_vars[0].is_empty()) {
 		normal = "NORMAL";
 	} else {
 		normal = p_input_vars[0];
 	}
-	if (p_input_vars[1] == String()) {
+	if (p_input_vars[1].is_empty()) {
 		view = "VIEW";
 	} else {
 		view = p_input_vars[1];
diff --git a/scene/resources/visual_shader_sdf_nodes.cpp b/scene/resources/visual_shader_sdf_nodes.cpp
index 14c655b129..0fe7c33396 100644
--- a/scene/resources/visual_shader_sdf_nodes.cpp
+++ b/scene/resources/visual_shader_sdf_nodes.cpp
@@ -61,7 +61,7 @@ String VisualShaderNodeSDFToScreenUV::get_output_port_name(int p_port) const {
 }
 
 String VisualShaderNodeSDFToScreenUV::generate_code(Shader::Mode p_mode, VisualShader::Type p_type, int p_id, const String *p_input_vars, const String *p_output_vars, bool p_for_preview) const {
-	return "		" + p_output_vars[0] + " = vec3(sdf_to_screen_uv(" + (p_input_vars[0] == String() ? "vec2(0.0)" : p_input_vars[0] + ".xy") + "), 0.0f);\n";
+	return "		" + p_output_vars[0] + " = vec3(sdf_to_screen_uv(" + (p_input_vars[0].is_empty() ? "vec2(0.0)" : p_input_vars[0] + ".xy") + "), 0.0f);\n";
 }
 
 VisualShaderNodeSDFToScreenUV::VisualShaderNodeSDFToScreenUV() {
@@ -105,7 +105,7 @@ String VisualShaderNodeScreenUVToSDF::get_input_port_default_hint(int p_port) co
 }
 
 String VisualShaderNodeScreenUVToSDF::generate_code(Shader::Mode p_mode, VisualShader::Type p_type, int p_id, const String *p_input_vars, const String *p_output_vars, bool p_for_preview) const {
-	return "		" + p_output_vars[0] + " = vec3(screen_uv_to_sdf(" + (p_input_vars[0] == String() ? "SCREEN_UV" : p_input_vars[0] + ".xy") + "), 0.0f);\n";
+	return "		" + p_output_vars[0] + " = vec3(screen_uv_to_sdf(" + (p_input_vars[0].is_empty() ? "SCREEN_UV" : p_input_vars[0] + ".xy") + "), 0.0f);\n";
 }
 
 VisualShaderNodeScreenUVToSDF::VisualShaderNodeScreenUVToSDF() {
@@ -142,7 +142,7 @@ String VisualShaderNodeTextureSDF::get_output_port_name(int p_port) const {
 }
 
 String VisualShaderNodeTextureSDF::generate_code(Shader::Mode p_mode, VisualShader::Type p_type, int p_id, const String *p_input_vars, const String *p_output_vars, bool p_for_preview) const {
-	return "		" + p_output_vars[0] + " = texture_sdf(" + (p_input_vars[0] == String() ? "vec2(0.0)" : p_input_vars[0] + ".xy") + ");\n";
+	return "		" + p_output_vars[0] + " = texture_sdf(" + (p_input_vars[0].is_empty() ? "vec2(0.0)" : p_input_vars[0] + ".xy") + ");\n";
 }
 
 VisualShaderNodeTextureSDF::VisualShaderNodeTextureSDF() {
@@ -179,7 +179,7 @@ String VisualShaderNodeTextureSDFNormal::get_output_port_name(int p_port) const
 }
 
 String VisualShaderNodeTextureSDFNormal::generate_code(Shader::Mode p_mode, VisualShader::Type p_type, int p_id, const String *p_input_vars, const String *p_output_vars, bool p_for_preview) const {
-	return "		" + p_output_vars[0] + " = vec3(texture_sdf_normal(" + (p_input_vars[0] == String() ? "vec2(0.0)" : p_input_vars[0] + ".xy") + "), 0.0f);\n";
+	return "		" + p_output_vars[0] + " = vec3(texture_sdf_normal(" + (p_input_vars[0].is_empty() ? "vec2(0.0)" : p_input_vars[0] + ".xy") + "), 0.0f);\n";
 }
 
 VisualShaderNodeTextureSDFNormal::VisualShaderNodeTextureSDFNormal() {
@@ -242,13 +242,13 @@ String VisualShaderNodeSDFRaymarch::generate_code(Shader::Mode p_mode, VisualSha
 
 	code += "		{\n";
 
-	if (p_input_vars[0] == String()) {
+	if (p_input_vars[0].is_empty()) {
 		code += "				vec2 __from_pos = vec2(0.0f);\n";
 	} else {
 		code += "				vec2 __from_pos = " + p_input_vars[0] + ".xy;\n";
 	}
 
-	if (p_input_vars[1] == String()) {
+	if (p_input_vars[1].is_empty()) {
 		code += "				vec2 __to_pos = vec2(0.0f);\n";
 	} else {
 		code += "				vec2 __to_pos = " + p_input_vars[1] + ".xy;\n";