5 files changed, 171 insertions, 188 deletions

diff --git a/core/string/optimized_translation.cpp b/core/string/optimized_translation.cpp
index 5863bd1c46..839b7a9c01 100644
--- a/core/string/optimized_translation.cpp
+++ b/core/string/optimized_translation.cpp
@@ -162,11 +162,11 @@ void OptimizedTranslation::generate(const Ref<Translation> &p_from) {
 		btw[btindex++] = t.size();
 		btw[btindex++] = hfunc_table[i];
 
-		for (Map<uint32_t, int>::Element *E = t.front(); E; E = E->next()) {
-			btw[btindex++] = E->key();
-			btw[btindex++] = compressed[E->get()].offset;
-			btw[btindex++] = compressed[E->get()].compressed.size();
-			btw[btindex++] = compressed[E->get()].orig_len;
+		for (const KeyValue<uint32_t, int> &E : t) {
+			btw[btindex++] = E.key;
+			btw[btindex++] = compressed[E.value].offset;
+			btw[btindex++] = compressed[E.value].compressed.size();
+			btw[btindex++] = compressed[E.value].orig_len;
 		}
 	}
 
diff --git a/core/string/translation.cpp b/core/string/translation.cpp
index cb7d924556..cf61467d08 100644
--- a/core/string/translation.cpp
+++ b/core/string/translation.cpp
@@ -35,7 +35,6 @@
 #include "core/os/os.h"
 
 #ifdef TOOLS_ENABLED
-#include "editor/editor_settings.h"
 #include "main/main.h"
 #endif
 
@@ -810,9 +809,12 @@ static const char *locale_names[] = {
 // - https://msdn.microsoft.com/en-us/library/windows/desktop/ms693062(v=vs.85).aspx
 
 static const char *locale_renames[][2] = {
-	{ "in", "id" }, //  Indonesian
-	{ "iw", "he" }, //  Hebrew
-	{ "no", "nb" }, //  Norwegian Bokmål
+	{ "in", "id" }, // Indonesian
+	{ "iw", "he" }, // Hebrew
+	{ "no", "nb" }, // Norwegian Bokmål
+	{ "C", "en" }, // "C" is the simple/default/untranslated Computer locale.
+	// ASCII-only, English, no currency symbols. Godot treats this as "en".
+	// See https://unix.stackexchange.com/a/87763/164141 "The C locale is"...
 	{ nullptr, nullptr }
 };
 
@@ -820,8 +822,8 @@ static const char *locale_renames[][2] = {
 
 Dictionary Translation::_get_messages() const {
 	Dictionary d;
-	for (const Map<StringName, StringName>::Element *E = translation_map.front(); E; E = E->next()) {
-		d[E->key()] = E->value();
+	for (const KeyValue<StringName, StringName> &E : translation_map) {
+		d[E.key] = E.value;
 	}
 	return d;
 }
@@ -830,8 +832,8 @@ Vector<String> Translation::_get_message_list() const {
 	Vector<String> msgs;
 	msgs.resize(translation_map.size());
 	int idx = 0;
-	for (const Map<StringName, StringName>::Element *E = translation_map.front(); E; E = E->next()) {
-		msgs.set(idx, E->key());
+	for (const KeyValue<StringName, StringName> &E : translation_map) {
+		msgs.set(idx, E.key);
 		idx += 1;
 	}
 
@@ -875,6 +877,11 @@ void Translation::add_plural_message(const StringName &p_src_text, const Vector<
 }
 
 StringName Translation::get_message(const StringName &p_src_text, const StringName &p_context) const {
+	StringName ret;
+	if (GDVIRTUAL_CALL(_get_message, p_src_text, p_context, ret)) {
+		return ret;
+	}
+
 	if (p_context != StringName()) {
 		WARN_PRINT("Translation class doesn't handle context. Using context in get_message() on a Translation instance is probably a mistake. \nUse a derived Translation class that handles context, such as TranslationPO class");
 	}
@@ -888,6 +895,11 @@ StringName Translation::get_message(const StringName &p_src_text, const StringNa
 }
 
 StringName Translation::get_plural_message(const StringName &p_src_text, const StringName &p_plural_text, int p_n, const StringName &p_context) const {
+	StringName ret;
+	if (GDVIRTUAL_CALL(_get_plural_message, p_src_text, p_plural_text, p_n, p_context, ret)) {
+		return ret;
+	}
+
 	WARN_PRINT("Translation class doesn't handle plural messages. Calling get_plural_message() on a Translation instance is probably a mistake. \nUse a derived Translation class that handles plurals, such as TranslationPO class");
 	return get_message(p_src_text);
 }
@@ -901,8 +913,8 @@ void Translation::erase_message(const StringName &p_src_text, const StringName &
 }
 
 void Translation::get_message_list(List<StringName> *r_messages) const {
-	for (const Map<StringName, StringName>::Element *E = translation_map.front(); E; E = E->next()) {
-		r_messages->push_back(E->key());
+	for (const KeyValue<StringName, StringName> &E : translation_map) {
+		r_messages->push_back(E.key);
 	}
 }
 
@@ -923,6 +935,9 @@ void Translation::_bind_methods() {
 	ClassDB::bind_method(D_METHOD("_set_messages"), &Translation::_set_messages);
 	ClassDB::bind_method(D_METHOD("_get_messages"), &Translation::_get_messages);
 
+	GDVIRTUAL_BIND(_get_plural_message, "src_message", "src_plural_message", "n", "context");
+	GDVIRTUAL_BIND(_get_message, "src_message", "context");
+
 	ADD_PROPERTY(PropertyInfo(Variant::DICTIONARY, "messages", PROPERTY_HINT_NONE, "", PROPERTY_USAGE_NOEDITOR | PROPERTY_USAGE_INTERNAL), "_set_messages", "_get_messages");
 	ADD_PROPERTY(PropertyInfo(Variant::STRING, "locale"), "set_locale", "get_locale");
 }
diff --git a/core/string/translation.h b/core/string/translation.h
index 4f179ac0fe..6aec0bb8ea 100644
--- a/core/string/translation.h
+++ b/core/string/translation.h
@@ -32,6 +32,8 @@
 #define TRANSLATION_H
 
 #include "core/io/resource.h"
+#include "core/object/gdvirtual.gen.inc"
+#include "core/object/script_language.h"
 
 class Translation : public Resource {
 	GDCLASS(Translation, Resource);
@@ -48,6 +50,9 @@ class Translation : public Resource {
 protected:
 	static void _bind_methods();
 
+	GDVIRTUAL2RC(StringName, _get_message, StringName, StringName);
+	GDVIRTUAL4RC(StringName, _get_plural_message, StringName, StringName, int, StringName);
+
 public:
 	void set_locale(const String &p_locale);
 	_FORCE_INLINE_ String get_locale() const { return locale; }
diff --git a/core/string/ustring.cpp b/core/string/ustring.cpp
index 7beecdb6b5..daeb7fbd17 100644
--- a/core/string/ustring.cpp
+++ b/core/string/ustring.cpp
@@ -39,12 +39,9 @@
 #include "core/string/ucaps.h"
 #include "core/variant/variant.h"
 
-#include <cstdint>
-
-#ifndef NO_USE_STDLIB
 #include <stdio.h>
 #include <stdlib.h>
-#endif
+#include <cstdint>
 
 #ifdef _MSC_VER
 #define _CRT_SECURE_NO_WARNINGS // to disable build-time warning which suggested to use strcpy_s instead strcpy
@@ -54,11 +51,27 @@
 #define snprintf _snprintf_s
 #endif
 
-#define MAX_DECIMALS 32
-#define UPPERCASE(m_c) (((m_c) >= 'a' && (m_c) <= 'z') ? ((m_c) - ('a' - 'A')) : (m_c))
-#define LOWERCASE(m_c) (((m_c) >= 'A' && (m_c) <= 'Z') ? ((m_c) + ('a' - 'A')) : (m_c))
-#define IS_DIGIT(m_d) ((m_d) >= '0' && (m_d) <= '9')
-#define IS_HEX_DIGIT(m_d) (((m_d) >= '0' && (m_d) <= '9') || ((m_d) >= 'a' && (m_d) <= 'f') || ((m_d) >= 'A' && (m_d) <= 'F'))
+static const int MAX_DECIMALS = 32;
+
+static _FORCE_INLINE_ bool is_digit(char32_t c) {
+	return (c >= '0' && c <= '9');
+}
+
+static _FORCE_INLINE_ bool is_hex_digit(char32_t c) {
+	return (is_digit(c) || (c >= 'a' && c <= 'f') || (c >= 'A' && c <= 'F'));
+}
+
+static _FORCE_INLINE_ bool is_upper_case(char32_t c) {
+	return (c >= 'A' && c <= 'Z');
+}
+
+static _FORCE_INLINE_ bool is_lower_case(char32_t c) {
+	return (c >= 'a' && c <= 'z');
+}
+
+static _FORCE_INLINE_ char32_t lower_case(char32_t c) {
+	return (is_upper_case(c) ? (c + ('a' - 'A')) : c);
+}
 
 const char CharString::_null = 0;
 const char16_t Char16String::_null = 0;
@@ -738,6 +751,7 @@ bool String::operator<=(const String &p_str) const {
 bool String::operator>(const String &p_str) const {
 	return p_str < *this;
 }
+
 bool String::operator>=(const String &p_str) const {
 	return !(*this < p_str);
 }
@@ -871,8 +885,8 @@ signed char String::naturalnocasecmp_to(const String &p_str) const {
 		while (*this_str) {
 			if (!*that_str) {
 				return 1;
-			} else if (IS_DIGIT(*this_str)) {
-				if (!IS_DIGIT(*that_str)) {
+			} else if (is_digit(*this_str)) {
+				if (!is_digit(*that_str)) {
 					return -1;
 				}
 
@@ -881,10 +895,10 @@ signed char String::naturalnocasecmp_to(const String &p_str) const {
 				const char32_t *that_substr = that_str;
 
 				// Compare lengths of both numerical sequences, ignoring leading zeros
-				while (IS_DIGIT(*this_str)) {
+				while (is_digit(*this_str)) {
 					this_str++;
 				}
-				while (IS_DIGIT(*that_str)) {
+				while (is_digit(*that_str)) {
 					that_str++;
 				}
 				while (*this_substr == '0') {
@@ -912,7 +926,7 @@ signed char String::naturalnocasecmp_to(const String &p_str) const {
 					this_substr++;
 					that_substr++;
 				}
-			} else if (IS_DIGIT(*that_str)) {
+			} else if (is_digit(*that_str)) {
 				return 1;
 			} else {
 				if (_find_upper(*this_str) < _find_upper(*that_str)) { //more than
@@ -962,26 +976,25 @@ String String::capitalize() const {
 String String::camelcase_to_underscore(bool lowercase) const {
 	const char32_t *cstr = get_data();
 	String new_string;
-	const char A = 'A', Z = 'Z';
-	const char a = 'a', z = 'z';
 	int start_index = 0;
 
 	for (int i = 1; i < this->size(); i++) {
-		bool is_upper = cstr[i] >= A && cstr[i] <= Z;
-		bool is_number = cstr[i] >= '0' && cstr[i] <= '9';
+		bool is_upper = is_upper_case(cstr[i]);
+		bool is_number = is_digit(cstr[i]);
+
 		bool are_next_2_lower = false;
 		bool is_next_lower = false;
 		bool is_next_number = false;
-		bool was_precedent_upper = cstr[i - 1] >= A && cstr[i - 1] <= Z;
-		bool was_precedent_number = cstr[i - 1] >= '0' && cstr[i - 1] <= '9';
+		bool was_precedent_upper = is_upper_case(cstr[i - 1]);
+		bool was_precedent_number = is_digit(cstr[i - 1]);
 
 		if (i + 2 < this->size()) {
-			are_next_2_lower = cstr[i + 1] >= a && cstr[i + 1] <= z && cstr[i + 2] >= a && cstr[i + 2] <= z;
+			are_next_2_lower = is_lower_case(cstr[i + 1]) && is_lower_case(cstr[i + 2]);
 		}
 
 		if (i + 1 < this->size()) {
-			is_next_lower = cstr[i + 1] >= a && cstr[i + 1] <= z;
-			is_next_number = cstr[i + 1] >= '0' && cstr[i + 1] <= '9';
+			is_next_lower = is_lower_case(cstr[i + 1]);
+			is_next_number = is_digit(cstr[i + 1]);
 		}
 
 		const bool cond_a = is_upper && !was_precedent_upper && !was_precedent_number;
@@ -1377,10 +1390,15 @@ String String::num(double p_num, int p_decimals) {
 			return "inf";
 		}
 	}
-#ifndef NO_USE_STDLIB
 
 	if (p_decimals < 0) {
-		p_decimals = 14 - (int)floor(log10(p_num));
+		p_decimals = 14;
+		const double abs_num = ABS(p_num);
+		if (abs_num > 10) {
+			// We want to align the digits to the above sane default, so we only
+			// need to subtract log10 for numbers with a positive power of ten.
+			p_decimals -= (int)floor(log10(abs_num));
+		}
 	}
 	if (p_decimals > MAX_DECIMALS) {
 		p_decimals = MAX_DECIMALS;
@@ -1444,87 +1462,6 @@ String String::num(double p_num, int p_decimals) {
 	}
 
 	return buf;
-#else
-
-	String s;
-	String sd;
-	/* integer part */
-
-	bool neg = p_num < 0;
-	p_num = ABS(p_num);
-	int intn = (int)p_num;
-
-	/* decimal part */
-
-	if (p_decimals > 0 || (p_decimals == -1 && (int)p_num != p_num)) {
-		double dec = p_num - (double)((int)p_num);
-
-		int digit = 0;
-		if (p_decimals > MAX_DECIMALS) {
-			p_decimals = MAX_DECIMALS;
-		}
-
-		int dec_int = 0;
-		int dec_max = 0;
-
-		while (true) {
-			dec *= 10.0;
-			dec_int = dec_int * 10 + (int)dec % 10;
-			dec_max = dec_max * 10 + 9;
-			digit++;
-
-			if (p_decimals == -1) {
-				if (digit == MAX_DECIMALS) { //no point in going to infinite
-					break;
-				}
-
-				if (dec - (double)((int)dec) < 1e-6) {
-					break;
-				}
-			}
-
-			if (digit == p_decimals) {
-				break;
-			}
-		}
-		dec *= 10;
-		int last = (int)dec % 10;
-
-		if (last > 5) {
-			if (dec_int == dec_max) {
-				dec_int = 0;
-				intn++;
-			} else {
-				dec_int++;
-			}
-		}
-
-		String decimal;
-		for (int i = 0; i < digit; i++) {
-			char num[2] = { 0, 0 };
-			num[0] = '0' + dec_int % 10;
-			decimal = num + decimal;
-			dec_int /= 10;
-		}
-		sd = '.' + decimal;
-	}
-
-	if (intn == 0)
-
-		s = "0";
-	else {
-		while (intn) {
-			char32_t num = '0' + (intn % 10);
-			intn /= 10;
-			s = num + s;
-		}
-	}
-
-	s = s + sd;
-	if (neg)
-		s = "-" + s;
-	return s;
-#endif
 }
 
 String String::num_int64(int64_t p_num, int base, bool capitalize_hex) {
@@ -1609,38 +1546,52 @@ String String::num_real(double p_num, bool p_trailing) {
 
 	String s;
 	String sd;
-	/* integer part */
+
+	// Integer part.
 
 	bool neg = p_num < 0;
 	p_num = ABS(p_num);
-	int intn = (int)p_num;
+	int64_t intn = (int64_t)p_num;
 
-	/* decimal part */
+	// Decimal part.
 
-	if ((int)p_num != p_num) {
-		double dec = p_num - (double)((int)p_num);
+	if (intn != p_num) {
+		double dec = p_num - (double)intn;
 
 		int digit = 0;
 
-#if REAL_T_IS_DOUBLE
-		int decimals = 14 - (int)floor(log10(p_num));
+#ifdef REAL_T_IS_DOUBLE
+		int decimals = 14;
+		double tolerance = 1e-14;
 #else
-		int decimals = 6 - (int)floor(log10(p_num));
+		int decimals = 6;
+		double tolerance = 1e-6;
 #endif
+		// We want to align the digits to the above sane default, so we only
+		// need to subtract log10 for numbers with a positive power of ten.
+		if (p_num > 10) {
+			decimals -= (int)floor(log10(p_num));
+		}
+
 		if (decimals > MAX_DECIMALS) {
 			decimals = MAX_DECIMALS;
 		}
 
-		int dec_int = 0;
-		int dec_max = 0;
+		// In case the value ends up ending in "99999", we want to add a
+		// tiny bit to the value we're checking when deciding when to stop,
+		// so we multiply by slightly above 1 (1 + 1e-7 or 1e-15).
+		double check_multiplier = 1 + tolerance / 10;
+
+		int64_t dec_int = 0;
+		int64_t dec_max = 0;
 
 		while (true) {
 			dec *= 10.0;
-			dec_int = dec_int * 10 + (int)dec % 10;
+			dec_int = dec_int * 10 + (int64_t)dec % 10;
 			dec_max = dec_max * 10 + 9;
 			digit++;
 
-			if ((dec - (double)((int)dec)) < 1e-6) {
+			if ((dec - (double)(int64_t)(dec * check_multiplier)) < tolerance) {
 				break;
 			}
 
@@ -1650,7 +1601,7 @@ String String::num_real(double p_num, bool p_trailing) {
 		}
 
 		dec *= 10;
-		int last = (int)dec % 10;
+		int last = (int64_t)dec % 10;
 
 		if (last > 5) {
 			if (dec_int == dec_max) {
@@ -1704,19 +1655,18 @@ String String::num_scientific(double p_num) {
 			return "inf";
 		}
 	}
-#ifndef NO_USE_STDLIB
 
 	char buf[256];
 
 #if defined(__GNUC__) || defined(_MSC_VER)
 
-#if (defined(__MINGW32__) || (defined(_MSC_VER) && _MSC_VER < 1900)) && defined(_TWO_DIGIT_EXPONENT) && !defined(_UCRT)
-	// MinGW and old MSC require _set_output_format() to conform to C99 output for printf
+#if defined(__MINGW32__) && defined(_TWO_DIGIT_EXPONENT) && !defined(_UCRT)
+	// MinGW requires _set_output_format() to conform to C99 output for printf
 	unsigned int old_exponent_format = _set_output_format(_TWO_DIGIT_EXPONENT);
 #endif
 	snprintf(buf, 256, "%lg", p_num);
 
-#if (defined(__MINGW32__) || (defined(_MSC_VER) && _MSC_VER < 1900)) && defined(_TWO_DIGIT_EXPONENT) && !defined(_UCRT)
+#if defined(__MINGW32__) && defined(_TWO_DIGIT_EXPONENT) && !defined(_UCRT)
 	_set_output_format(old_exponent_format);
 #endif
 
@@ -1727,10 +1677,6 @@ String String::num_scientific(double p_num) {
 	buf[255] = 0;
 
 	return buf;
-#else
-
-	return String::num(p_num);
-#endif
 }
 
 String String::md5(const uint8_t *p_md5) {
@@ -2198,9 +2144,9 @@ int64_t String::hex_to_int() const {
 	int64_t hex = 0;
 
 	while (*s) {
-		char32_t c = LOWERCASE(*s);
+		char32_t c = lower_case(*s);
 		int64_t n;
-		if (c >= '0' && c <= '9') {
+		if (is_digit(c)) {
 			n = c - '0';
 		} else if (c >= 'a' && c <= 'f') {
 			n = (c - 'a') + 10;
@@ -2239,7 +2185,7 @@ int64_t String::bin_to_int() const {
 	int64_t binary = 0;
 
 	while (*s) {
-		char32_t c = LOWERCASE(*s);
+		char32_t c = lower_case(*s);
 		int64_t n;
 		if (c == '0' || c == '1') {
 			n = c - '0';
@@ -2269,7 +2215,7 @@ int64_t String::to_int() const {
 
 	for (int i = 0; i < to; i++) {
 		char32_t c = operator[](i);
-		if (c >= '0' && c <= '9') {
+		if (is_digit(c)) {
 			bool overflow = (integer > INT64_MAX / 10) || (integer == INT64_MAX / 10 && ((sign == 1 && c > '7') || (sign == -1 && c > '8')));
 			ERR_FAIL_COND_V_MSG(overflow, sign == 1 ? INT64_MAX : INT64_MIN, "Cannot represent " + *this + " as 64-bit integer, provided value is " + (sign == 1 ? "too big." : "too small."));
 			integer *= 10;
@@ -2298,7 +2244,7 @@ int64_t String::to_int(const char *p_str, int p_len) {
 
 	for (int i = 0; i < to; i++) {
 		char c = p_str[i];
-		if (c >= '0' && c <= '9') {
+		if (is_digit(c)) {
 			bool overflow = (integer > INT64_MAX / 10) || (integer == INT64_MAX / 10 && ((sign == 1 && c > '7') || (sign == -1 && c > '8')));
 			ERR_FAIL_COND_V_MSG(overflow, sign == 1 ? INT64_MAX : INT64_MIN, "Cannot represent " + String(p_str).substr(0, to) + " as integer, provided value is " + (sign == 1 ? "too big." : "too small."));
 			integer *= 10;
@@ -2329,7 +2275,7 @@ int64_t String::to_int(const wchar_t *p_str, int p_len) {
 
 	for (int i = 0; i < to; i++) {
 		wchar_t c = p_str[i];
-		if (c >= '0' && c <= '9') {
+		if (is_digit(c)) {
 			bool overflow = (integer > INT64_MAX / 10) || (integer == INT64_MAX / 10 && ((sign == 1 && c > '7') || (sign == -1 && c > '8')));
 			ERR_FAIL_COND_V_MSG(overflow, sign == 1 ? INT64_MAX : INT64_MIN, "Cannot represent " + String(p_str).substr(0, to) + " as integer, provided value is " + (sign == 1 ? "too big." : "too small."));
 			integer *= 10;
@@ -2449,7 +2395,7 @@ static double built_in_strtod(const C *string, /* A decimal ASCII floating-point
 	decPt = -1;
 	for (mantSize = 0;; mantSize += 1) {
 		c = *p;
-		if (!IS_DIGIT(c)) {
+		if (!is_digit(c)) {
 			if ((c != '.') || (decPt >= 0)) {
 				break;
 			}
@@ -2524,11 +2470,11 @@ static double built_in_strtod(const C *string, /* A decimal ASCII floating-point
 			}
 			expSign = false;
 		}
-		if (!IS_DIGIT(char32_t(*p))) {
+		if (!is_digit(char32_t(*p))) {
 			p = pExp;
 			goto done;
 		}
-		while (IS_DIGIT(char32_t(*p))) {
+		while (is_digit(char32_t(*p))) {
 			exp = exp * 10 + (*p - '0');
 			p += 1;
 		}
@@ -2614,7 +2560,7 @@ int64_t String::to_int(const char32_t *p_str, int p_len, bool p_clamp) {
 		char32_t c = *(str++);
 		switch (reading) {
 			case READING_SIGN: {
-				if (c >= '0' && c <= '9') {
+				if (is_digit(c)) {
 					reading = READING_INT;
 					// let it fallthrough
 				} else if (c == '-') {
@@ -2631,7 +2577,7 @@ int64_t String::to_int(const char32_t *p_str, int p_len, bool p_clamp) {
 				[[fallthrough]];
 			}
 			case READING_INT: {
-				if (c >= '0' && c <= '9') {
+				if (is_digit(c)) {
 					if (integer > INT64_MAX / 10) {
 						String number("");
 						str = p_str;
@@ -3616,7 +3562,7 @@ String String::strip_edges(bool left, bool right) const {
 	}
 
 	if (right) {
-		for (int i = (int)(len - 1); i >= 0; i--) {
+		for (int i = len - 1; i >= 0; i--) {
 			if (operator[](i) <= 32) {
 				end--;
 			} else {
@@ -3800,12 +3746,12 @@ bool String::is_valid_identifier() const {
 
 	for (int i = 0; i < len; i++) {
 		if (i == 0) {
-			if (str[0] >= '0' && str[0] <= '9') {
+			if (is_digit(str[0])) {
 				return false; // no start with number plz
 			}
 		}
 
-		bool valid_char = (str[i] >= '0' && str[i] <= '9') || (str[i] >= 'a' && str[i] <= 'z') || (str[i] >= 'A' && str[i] <= 'Z') || str[i] == '_';
+		bool valid_char = is_digit(str[i]) || is_lower_case(str[i]) || is_upper_case(str[i]) || str[i] == '_';
 
 		if (!valid_char) {
 			return false;
@@ -3830,10 +3776,7 @@ String String::uri_encode() const {
 	String res;
 	for (int i = 0; i < temp.length(); ++i) {
 		char ord = temp[i];
-		if (ord == '.' || ord == '-' || ord == '_' || ord == '~' ||
-				(ord >= 'a' && ord <= 'z') ||
-				(ord >= 'A' && ord <= 'Z') ||
-				(ord >= '0' && ord <= '9')) {
+		if (ord == '.' || ord == '-' || ord == '_' || ord == '~' || is_lower_case(ord) || is_upper_case(ord) || is_digit(ord)) {
 			res += ord;
 		} else {
 			char h_Val[3];
@@ -3855,9 +3798,9 @@ String String::uri_decode() const {
 	for (int i = 0; i < src.length(); ++i) {
 		if (src[i] == '%' && i + 2 < src.length()) {
 			char ord1 = src[i + 1];
-			if ((ord1 >= '0' && ord1 <= '9') || (ord1 >= 'A' && ord1 <= 'Z')) {
+			if (is_digit(ord1) || is_upper_case(ord1)) {
 				char ord2 = src[i + 2];
-				if ((ord2 >= '0' && ord2 <= '9') || (ord2 >= 'A' && ord2 <= 'Z')) {
+				if (is_digit(ord2) || is_upper_case(ord2)) {
 					char bytes[3] = { (char)ord1, (char)ord2, 0 };
 					res += (char)strtol(bytes, nullptr, 16);
 					i += 2;
@@ -3963,7 +3906,7 @@ static _FORCE_INLINE_ int _xml_unescape(const char32_t *p_src, int p_src_len, ch
 						char32_t ct = p_src[i];
 						if (ct == ';') {
 							break;
-						} else if (ct >= '0' && ct <= '9') {
+						} else if (is_digit(ct)) {
 							ct = ct - '0';
 						} else if (ct >= 'a' && ct <= 'f') {
 							ct = (ct - 'a') + 10;
@@ -4191,7 +4134,7 @@ bool String::is_valid_hex_number(bool p_with_prefix) const {
 
 	for (int i = from; i < len; i++) {
 		char32_t c = operator[](i);
-		if ((c >= '0' && c <= '9') || (c >= 'a' && c <= 'f') || (c >= 'A' && c <= 'F')) {
+		if (is_hex_digit(c)) {
 			continue;
 		}
 		return false;
@@ -4219,7 +4162,7 @@ bool String::is_valid_float() const {
 	bool numbers_found = false;
 
 	for (int i = from; i < len; i++) {
-		if (operator[](i) >= '0' && operator[](i) <= '9') {
+		if (is_digit(operator[](i))) {
 			if (exponent_found) {
 				exponent_values_found = true;
 			} else {
@@ -4388,28 +4331,44 @@ bool String::is_resource_file() const {
 	return begins_with("res://") && find("::") == -1;
 }
 
-bool String::is_rel_path() const {
+bool String::is_relative_path() const {
 	return !is_absolute_path();
 }
 
 String String::get_base_dir() const {
-	int basepos = find(":/");
-	if (basepos == -1) {
-		basepos = find(":\\");
+	int end = 0;
+
+	// url scheme style base
+	int basepos = find("://");
+	if (basepos != -1) {
+		end = basepos + 3;
+	}
+
+	// windows top level directory base
+	if (end == 0) {
+		basepos = find(":/");
+		if (basepos == -1) {
+			basepos = find(":\\");
+		}
+		if (basepos != -1) {
+			end = basepos + 2;
+		}
 	}
+
+	// unix root directory base
+	if (end == 0) {
+		if (begins_with("/")) {
+			end = 1;
+		}
+	}
+
 	String rs;
 	String base;
-	if (basepos != -1) {
-		int end = basepos + 3;
+	if (end != 0) {
 		rs = substr(end, length());
 		base = substr(0, end);
 	} else {
-		if (begins_with("/")) {
-			rs = substr(1, length());
-			base = "/";
-		} else {
-			rs = *this;
-		}
+		rs = *this;
 	}
 
 	int sep = MAX(rs.rfind("/"), rs.rfind("\\"));
diff --git a/core/string/ustring.h b/core/string/ustring.h
index ffb354d6e1..1d80ccf58d 100644
--- a/core/string/ustring.h
+++ b/core/string/ustring.h
@@ -51,11 +51,15 @@ class CharProxy {
 	CowData<T> &_cowdata;
 	static const T _null = 0;
 
-	_FORCE_INLINE_ CharProxy(const int &p_index, CowData<T> &cowdata) :
+	_FORCE_INLINE_ CharProxy(const int &p_index, CowData<T> &p_cowdata) :
 			_index(p_index),
-			_cowdata(cowdata) {}
+			_cowdata(p_cowdata) {}
 
 public:
+	_FORCE_INLINE_ CharProxy(const CharProxy<T> &p_other) :
+			_index(p_other._index),
+			_cowdata(p_other._cowdata) {}
+
 	_FORCE_INLINE_ operator T() const {
 		if (unlikely(_index == _cowdata.size())) {
 			return _null;
@@ -68,12 +72,12 @@ public:
 		return _cowdata.ptr() + _index;
 	}
 
-	_FORCE_INLINE_ void operator=(const T &other) const {
-		_cowdata.set(_index, other);
+	_FORCE_INLINE_ void operator=(const T &p_other) const {
+		_cowdata.set(_index, p_other);
 	}
 
-	_FORCE_INLINE_ void operator=(const CharProxy<T> &other) const {
-		_cowdata.set(_index, other.operator T());
+	_FORCE_INLINE_ void operator=(const CharProxy<T> &p_other) const {
+		_cowdata.set(_index, p_other.operator T());
 	}
 };
 
@@ -398,7 +402,7 @@ public:
 
 	// path functions
 	bool is_absolute_path() const;
-	bool is_rel_path() const;
+	bool is_relative_path() const;
 	bool is_resource_file() const;
 	String path_to(const String &p_path) const;
 	String path_to_file(const String &p_path) const;
@@ -523,10 +527,10 @@ String DTRN(const String &p_text, const String &p_text_plural, int p_n, const St
 #define TTRGET(m_value) TTR(m_value)
 
 #else
-#define TTR(m_value) (String())
-#define TTRN(m_value) (String())
-#define DTR(m_value) (String())
-#define DTRN(m_value) (String())
+#define TTR(m_value) String()
+#define TTRN(m_value) String()
+#define DTR(m_value) String()
+#define DTRN(m_value) String()
 #define TTRC(m_value) (m_value)
 #define TTRGET(m_value) (m_value)
 #endif