Add "AstStatDeclareGlobal" to the Transpiler, so you can use it with Luau::toString (#1889)

Analysis/src/Transpiler.cpp

@@ -1252,6 +1252,15 @@ struct Printer
 
             writer.symbol(")");
         }
+        else if (const auto& a = program.as<AstStatDeclareGlobal>())
+        {
+            writer.keyword("declare");
+            writer.advance(a->nameLocation.begin);
+            writer.identifier(a->name.value);
+
+            writer.symbol(":");
+            visualizeTypeAnnotation(*a->type);
+        }
         else
         {
             LUAU_ASSERT(!"Unknown AstStat");

tests/Transpiler.test.cpp

@@ -1568,6 +1568,22 @@ TEST_CASE_FIXTURE(Fixture, "transpile_parse_error")
     CHECK_EQ("Expected identifier when parsing expression, got <eof>", result.parseError);
 }
 
+TEST_CASE_FIXTURE(Fixture, "transpile_declare_global_stat")
+{
+    std::string code = "declare _G: any";
+
+    ParseOptions options;
+    options.allowDeclarationSyntax = true;
+
+    auto allocator = Allocator{};
+    auto names = AstNameTable{allocator};
+    ParseResult parseResult = Parser::parse(code.data(), code.size(), names, allocator, options);
+
+    auto result = transpileWithTypes(*parseResult.root);
+
+    CHECK_EQ(result, code);
+}
+
 TEST_CASE_FIXTURE(Fixture, "transpile_to_string")
 {
     std::string code = "local a: string = 'hello'";