Make more types (`Callable`, `Signal`) conversion to `String` explicit.

core/string/translation_server.h

@@ -77,7 +77,7 @@ class TranslationServer : public Object {
 					(p_locale.variant == variant);
 		}
 
-		operator String() const;
+		explicit operator String() const;
 
 		Locale(const TranslationServer &p_server, const String &p_locale, bool p_add_defaults);
 	};

core/templates/hashfuncs.h

@@ -55,6 +55,7 @@
 #include "core/templates/pair.h"
 #include "core/templates/rid.h"
 #include "core/typedefs.h"
+#include "core/variant/callable.h"
 
 #ifdef _MSC_VER
 #include <intrin.h> // Needed for `__umulh` below.
@@ -342,6 +343,7 @@ struct HashMapHasherDefault {
 	static _FORCE_INLINE_ uint32_t hash(const StringName &p_string_name) { return p_string_name.hash(); }
 	static _FORCE_INLINE_ uint32_t hash(const NodePath &p_path) { return p_path.hash(); }
 	static _FORCE_INLINE_ uint32_t hash(const ObjectID &p_id) { return hash_one_uint64(p_id); }
+	static _FORCE_INLINE_ uint32_t hash(const Callable &p_callable) { return p_callable.hash(); }
 
 	static _FORCE_INLINE_ uint32_t hash(const uint64_t p_int) { return hash_one_uint64(p_int); }
 	static _FORCE_INLINE_ uint32_t hash(const int64_t p_int) { return hash_one_uint64(uint64_t(p_int)); }

core/variant/callable.h

@@ -123,7 +123,7 @@ public:
 
 	void operator=(const Callable &p_callable);
 
-	operator String() const;
+	explicit operator String() const;
 
 	static Callable create(const Variant &p_variant, const StringName &p_method);
 
@@ -190,7 +190,7 @@ public:
 	bool operator!=(const Signal &p_signal) const;
 	bool operator<(const Signal &p_signal) const;
 
-	operator String() const;
+	explicit operator String() const;
 
 	Error emit(const Variant **p_arguments, int p_argcount) const;
 	Error connect(const Callable &p_callable, uint32_t p_flags = 0);

core/variant/method_ptrcall.h

@@ -131,7 +131,7 @@ struct PtrToArgStringConvertByReference {
 	// No EncodeT because direct pointer conversion not possible.
 	_FORCE_INLINE_ static void encode(const T &p_vec, void *p_ptr) {
 		String *arr = reinterpret_cast<String *>(p_ptr);
-		*arr = p_vec;
+		*arr = String(p_vec);
 	}
 };
 

core/variant/variant.cpp

@@ -1725,11 +1725,11 @@ String Variant::stringify(int recursion_count) const {
 		}
 		case CALLABLE: {
 			const Callable &c = *reinterpret_cast<const Callable *>(_data._mem);
-			return c;
+			return String(c);
 		}
 		case SIGNAL: {
 			const Signal &s = *reinterpret_cast<const Signal *>(_data._mem);
-			return s;
+			return String(s);
 		}
 		case RID: {
 			const ::RID &s = *reinterpret_cast<const ::RID *>(_data._mem);