feat(40674): make error messages more consistent (#40675)

Author: a-tarasyuk

src/compiler/checker.ts

@@ -39487,7 +39487,7 @@ namespace ts {
             if (node.exclamationToken && (node.parent.parent.kind !== SyntaxKind.VariableStatement || !node.type || node.initializer || node.flags & NodeFlags.Ambient)) {
                 const message = node.initializer
                     ? Diagnostics.Declarations_with_initializers_cannot_also_have_definite_assignment_assertions
-                    : Diagnostics.Definite_assignment_assertions_can_only_be_used_along_with_a_type_annotation;
+                    : Diagnostics.Declarations_with_definite_assignment_assertions_must_also_have_type_annotations;
                 return grammarErrorOnNode(node.exclamationToken, message);
             }
 

src/compiler/diagnosticMessages.json

@@ -851,10 +851,6 @@
         "category": "Error",
         "code": 1257
     },
-    "Definite assignment assertions can only be used along with a type annotation.": {
-        "category": "Error",
-        "code": 1258
-    },
     "Module '{0}' can only be default-imported using the '{1}' flag": {
         "category": "Error",
         "code": 1259

tests/baselines/reference/definiteAssignmentAssertions.errors.txt

@@ -6,11 +6,11 @@ tests/cases/conformance/controlFlow/definiteAssignmentAssertions.ts(23,5): error
 tests/cases/conformance/controlFlow/definiteAssignmentAssertions.ts(23,6): error TS1264: Declarations with definite assignment assertions must also have type annotations.
 tests/cases/conformance/controlFlow/definiteAssignmentAssertions.ts(29,6): error TS1255: A definite assignment assertion '!' is not permitted in this context.
 tests/cases/conformance/controlFlow/definiteAssignmentAssertions.ts(35,15): error TS1255: A definite assignment assertion '!' is not permitted in this context.
-tests/cases/conformance/controlFlow/definiteAssignmentAssertions.ts(69,10): error TS1258: Definite assignment assertions can only be used along with a type annotation.
+tests/cases/conformance/controlFlow/definiteAssignmentAssertions.ts(69,10): error TS1264: Declarations with definite assignment assertions must also have type annotations.
 tests/cases/conformance/controlFlow/definiteAssignmentAssertions.ts(70,10): error TS1263: Declarations with initializers cannot also have definite assignment assertions.
 tests/cases/conformance/controlFlow/definiteAssignmentAssertions.ts(71,10): error TS1263: Declarations with initializers cannot also have definite assignment assertions.
-tests/cases/conformance/controlFlow/definiteAssignmentAssertions.ts(76,15): error TS1258: Definite assignment assertions can only be used along with a type annotation.
-tests/cases/conformance/controlFlow/definiteAssignmentAssertions.ts(77,15): error TS1258: Definite assignment assertions can only be used along with a type annotation.
+tests/cases/conformance/controlFlow/definiteAssignmentAssertions.ts(76,15): error TS1264: Declarations with definite assignment assertions must also have type annotations.
+tests/cases/conformance/controlFlow/definiteAssignmentAssertions.ts(77,15): error TS1264: Declarations with definite assignment assertions must also have type annotations.
 
 
 ==== tests/cases/conformance/controlFlow/definiteAssignmentAssertions.ts (13 errors) ====
@@ -100,7 +100,7 @@ tests/cases/conformance/controlFlow/definiteAssignmentAssertions.ts(77,15): erro
     function f4() {
         let a!;
              ~
-!!! error TS1258: Definite assignment assertions can only be used along with a type annotation.
+!!! error TS1264: Declarations with definite assignment assertions must also have type annotations.
         let b! = 1;
              ~
 !!! error TS1263: Declarations with initializers cannot also have definite assignment assertions.
@@ -113,8 +113,8 @@ tests/cases/conformance/controlFlow/definiteAssignmentAssertions.ts(77,15): erro
 
     declare let v1!: number;
                   ~
-!!! error TS1258: Definite assignment assertions can only be used along with a type annotation.
+!!! error TS1264: Declarations with definite assignment assertions must also have type annotations.
     declare var v2!: number;
                   ~
-!!! error TS1258: Definite assignment assertions can only be used along with a type annotation.
+!!! error TS1264: Declarations with definite assignment assertions must also have type annotations.