Merge pull request microsoft#28132 from a-tarasyuk/feature/28086

28086 - "--downlevelIteration errors should mention using later targets"

Author: DanielRosenwasser

src/compiler/checker.ts

@@ -26053,7 +26053,7 @@ namespace ts {
                         ? downlevelIteration
                             ? Diagnostics.Type_0_is_not_an_array_type_or_does_not_have_a_Symbol_iterator_method_that_returns_an_iterator
                             : isIterable
-                                ? Diagnostics.Type_0_is_not_an_array_type_Use_compiler_option_downlevelIteration_to_allow_iterating_of_iterators
+                                ? Diagnostics.Type_0_is_not_an_array_type_or_a_string_type_Use_compiler_option_downlevelIteration_to_allow_iterating_of_iterators
                                 : Diagnostics.Type_0_is_not_an_array_type
                         : downlevelIteration
                             ? Diagnostics.Type_0_is_not_an_array_type_or_a_string_type_or_does_not_have_a_Symbol_iterator_method_that_returns_an_iterator

src/compiler/diagnosticMessages.json

@@ -2056,10 +2056,6 @@
         "category": "Error",
         "code": 2567
     },
-    "Type '{0}' is not an array type. Use compiler option '--downlevelIteration' to allow iterating of iterators.": {
-        "category": "Error",
-        "code": 2568
-    },
     "Type '{0}' is not an array type or a string type. Use compiler option '--downlevelIteration' to allow iterating of iterators.": {
         "category": "Error",
         "code": 2569

tests/baselines/reference/ES5For-ofTypeCheck14.errors.txt

@@ -1,8 +1,8 @@
-tests/cases/conformance/statements/for-ofStatements/ES5For-ofTypeCheck14.ts(2,17): error TS2568: Type 'Set<number>' is not an array type. Use compiler option '--downlevelIteration' to allow iterating of iterators.
+tests/cases/conformance/statements/for-ofStatements/ES5For-ofTypeCheck14.ts(2,17): error TS2569: Type 'Set<number>' is not an array type or a string type. Use compiler option '--downlevelIteration' to allow iterating of iterators.
 
 
 ==== tests/cases/conformance/statements/for-ofStatements/ES5For-ofTypeCheck14.ts (1 errors) ====
     var union: string | Set<number>
     for (const e of union) { }
                     ~~~~~
-!!! error TS2568: Type 'Set<number>' is not an array type. Use compiler option '--downlevelIteration' to allow iterating of iterators.
+!!! error TS2569: Type 'Set<number>' is not an array type or a string type. Use compiler option '--downlevelIteration' to allow iterating of iterators.