5 files changed, 39 insertions, 21 deletions

diff --git a/modules/gdscript/gd_editor.cpp b/modules/gdscript/gd_editor.cpp
index de8e35c406..346b7d326a 100644
--- a/modules/gdscript/gd_editor.cpp
+++ b/modules/gdscript/gd_editor.cpp
@@ -337,6 +337,11 @@ void GDScriptLanguage::get_public_constants(List<Pair<String, Variant> > *p_cons
 	pi.second = Math_PI;
 	p_constants->push_back(pi);
 
+	Pair<String, Variant> tau;
+	tau.first = "TAU";
+	tau.second = Math_TAU;
+	p_constants->push_back(tau);
+
 	Pair<String, Variant> infinity;
 	infinity.first = "INF";
 	infinity.second = Math_INF;
@@ -2771,31 +2776,31 @@ Error GDScriptLanguage::lookup_code(const String &p_code, const String &p_symbol
 				}
 
 				//global
-				for (Map<StringName, int>::Element *E = GDScriptLanguage::get_singleton()->get_global_map().front(); E; E = E->next()) {
-					if (E->key() == p_symbol) {
-
-						Variant value = GDScriptLanguage::get_singleton()->get_global_array()[E->get()];
-						if (value.get_type() == Variant::OBJECT) {
-							Object *obj = value;
-							if (obj) {
-
-								if (Object::cast_to<GDNativeClass>(obj)) {
-									r_result.type = ScriptLanguage::LookupResult::RESULT_CLASS;
-									r_result.class_name = Object::cast_to<GDNativeClass>(obj)->get_name();
-
-								} else {
-									r_result.type = ScriptLanguage::LookupResult::RESULT_CLASS;
-									r_result.class_name = obj->get_class();
-								}
-								return OK;
+				Map<StringName, int> classes = GDScriptLanguage::get_singleton()->get_global_map();
+				if (classes.has(p_symbol)) {
+					Variant value = GDScriptLanguage::get_singleton()->get_global_array()[classes[p_symbol]];
+					if (value.get_type() == Variant::OBJECT) {
+						Object *obj = value;
+						if (obj) {
+							if (Object::cast_to<GDNativeClass>(obj)) {
+								r_result.type = ScriptLanguage::LookupResult::RESULT_CLASS;
+								r_result.class_name = Object::cast_to<GDNativeClass>(obj)->get_name();
+							} else {
+								r_result.type = ScriptLanguage::LookupResult::RESULT_CLASS;
+								r_result.class_name = obj->get_class();
 							}
-						} else {
 
-							r_result.type = ScriptLanguage::LookupResult::RESULT_CLASS_CONSTANT;
-							r_result.class_name = "@Global Scope";
-							r_result.class_member = p_symbol;
+							// proxy class remove the underscore.
+							if (r_result.class_name.begins_with("_")) {
+								r_result.class_name = r_result.class_name.right(1);
+							}
 							return OK;
 						}
+					} else {
+						r_result.type = ScriptLanguage::LookupResult::RESULT_CLASS_CONSTANT;
+						r_result.class_name = "@Global Scope";
+						r_result.class_member = p_symbol;
+						return OK;
 					}
 				}
 			}
diff --git a/modules/gdscript/gd_parser.cpp b/modules/gdscript/gd_parser.cpp
index 94385dc0d0..d7e83c3a33 100644
--- a/modules/gdscript/gd_parser.cpp
+++ b/modules/gdscript/gd_parser.cpp
@@ -362,6 +362,13 @@ GDParser::Node *GDParser::_parse_expression(Node *p_parent, bool p_static, bool
 			constant->value = Math_PI;
 			tokenizer->advance();
 			expr = constant;
+		} else if (tokenizer->get_token() == GDTokenizer::TK_CONST_TAU) {
+
+			//constant defined by tokenizer
+			ConstantNode *constant = alloc_node<ConstantNode>();
+			constant->value = Math_TAU;
+			tokenizer->advance();
+			expr = constant;
 		} else if (tokenizer->get_token() == GDTokenizer::TK_CONST_INF) {
 
 			//constant defined by tokenizer
diff --git a/modules/gdscript/gd_script.cpp b/modules/gdscript/gd_script.cpp
index 3f3818ffb9..e5016c59bd 100644
--- a/modules/gdscript/gd_script.cpp
+++ b/modules/gdscript/gd_script.cpp
@@ -1324,6 +1324,7 @@ void GDScriptLanguage::init() {
 	}
 
 	_add_global(StaticCString::create("PI"), Math_PI);
+	_add_global(StaticCString::create("TAU"), Math_TAU);
 	_add_global(StaticCString::create("INF"), Math_INF);
 	_add_global(StaticCString::create("NAN"), Math_NAN);
 
@@ -1700,6 +1701,7 @@ void GDScriptLanguage::get_reserved_words(List<String> *p_words) const {
 		"bool",
 		"null",
 		"PI",
+		"TAU",
 		"INF",
 		"NAN",
 		"self",
diff --git a/modules/gdscript/gd_tokenizer.cpp b/modules/gdscript/gd_tokenizer.cpp
index 5f85158232..98ac0f473d 100644
--- a/modules/gdscript/gd_tokenizer.cpp
+++ b/modules/gdscript/gd_tokenizer.cpp
@@ -123,6 +123,7 @@ const char *GDTokenizer::token_names[TK_MAX] = {
 	"'$'",
 	"'\\n'",
 	"PI",
+	"TAU",
 	"_",
 	"INF",
 	"NAN",
@@ -217,6 +218,7 @@ static const _kws _keyword_list[] = {
 	{ GDTokenizer::TK_CF_PASS, "pass" },
 	{ GDTokenizer::TK_SELF, "self" },
 	{ GDTokenizer::TK_CONST_PI, "PI" },
+	{ GDTokenizer::TK_CONST_TAU, "TAU" },
 	{ GDTokenizer::TK_WILDCARD, "_" },
 	{ GDTokenizer::TK_CONST_INF, "INF" },
 	{ GDTokenizer::TK_CONST_NAN, "NAN" },
@@ -280,6 +282,7 @@ bool GDTokenizer::is_token_literal(int p_offset, bool variable_safe) const {
 		case TK_CF_PASS:
 		case TK_SELF:
 		case TK_CONST_PI:
+		case TK_CONST_TAU:
 		case TK_WILDCARD:
 		case TK_CONST_INF:
 		case TK_CONST_NAN:
diff --git a/modules/gdscript/gd_tokenizer.h b/modules/gdscript/gd_tokenizer.h
index c935ce45a1..f4b579def4 100644
--- a/modules/gdscript/gd_tokenizer.h
+++ b/modules/gdscript/gd_tokenizer.h
@@ -128,6 +128,7 @@ public:
 		TK_DOLLAR,
 		TK_NEWLINE,
 		TK_CONST_PI,
+		TK_CONST_TAU,
 		TK_WILDCARD,
 		TK_CONST_INF,
 		TK_CONST_NAN,