fix(29648): Error message related to JSDoc for non-JSDoc syntax error (#50793)

* fix(29648): improve diagnostics of non-JSDoc syntax errors

* fix lint errors

* update tests

* change diagnostic type suggestion. fix QF for jsdoc nullable type

* move error handling from the parser to the checker

* change diagnostic message. remove speculative parsing

* update baseline

tests/cases/compiler/parseInvalidNonNullableTypes.ts

@@ -0,0 +1,24 @@
+// @strict: true
+
+function f1(a: string): a is string! {
+    return true;
+}
+
+function f2(a: string): a is !string {
+    return true;
+}
+
+function f3(a: string!) {}
+function f4(a: number!) {}
+
+function f5(a: !string) {}
+function f6(a: !number) {}
+
+function f7(): string! {}
+function f8(): !string {}
+
+const a = 1 as any!;
+const b: number! = 1;
+
+const c = 1 as !any;
+const d: !number = 1;

tests/cases/compiler/parseInvalidNullableTypes.ts

@@ -0,0 +1,26 @@
+// @strict: true
+
+function f1(a: string): a is ?string {
+    return true;
+}
+
+function f2(a: string?) {}
+function f3(a: number?) {}
+
+function f4(a: ?string) {}
+function f5(a: ?number) {}
+
+function f6(a: string): ?string {
+    return true;
+}
+
+const a = 1 as any?;
+const b: number? = 1;
+
+const c = 1 as ?any;
+const d: ?number = 1;
+
+let e: unknown?;
+let f: never?;
+let g: void?;
+let h: undefined?;

tests/cases/fourslash/codeFixChangeJSDocSyntax10.ts

@@ -4,8 +4,8 @@
 //// }
 
 verify.codeFix({
-    description: "Change 'number?' to 'number | null'",
-    errorCode: 8020,
+    description: "Change 'number?' to 'number | undefined'",
+    errorCode: 17019,
     index: 0,
-    newRangeContent: "number | null",
+    newRangeContent: "number | undefined",
 });

tests/cases/fourslash/codeFixChangeJSDocSyntax11.ts

@@ -4,8 +4,8 @@
 //// }
 
 verify.codeFix({
-    description: "Change 'string?' to 'string | null | undefined'",
-    errorCode: 8020,
+    description: "Change 'string?' to 'string | undefined'",
+    errorCode: 17019,
     index: 1,
-    newRangeContent: "string | null | undefined",
+    newRangeContent: "string | undefined",
 });

tests/cases/fourslash/codeFixChangeJSDocSyntax14.ts

@@ -3,8 +3,8 @@
 //// var x = 12 as [|number?|];
 
 verify.codeFix({
-    description: "Change 'number?' to 'number | null'",
-    errorCode: 8020,
+    description: "Change 'number?' to 'number | undefined'",
+    errorCode: 17019,
     index: 0,
-    newRangeContent: "number | null",
+    newRangeContent: "number | undefined",
 });

tests/cases/fourslash/codeFixChangeJSDocSyntax15.ts

@@ -2,8 +2,16 @@
 //// var f = <[|function(number?): number|]>(x => x);
 
 verify.codeFix({
-    description: "Change 'function(number?): number' to '(arg0: number) => number'",
+    description: "Change 'number?' to 'number'",
+    errorCode: 17019,
+    index: 0,
+    newRangeContent: "function(number): number",
+    applyChanges: true
+});
+
+verify.codeFix({
+    description: "Change 'function(number): number' to '(arg0: number) => number'",
     errorCode: 8020,
     index: 0,
-    newRangeContent: "(arg0: number | null) => number",
+    newRangeContent: "(arg0: number) => number",
 });

tests/cases/fourslash/codeFixChangeJSDocSyntax27.ts

@@ -0,0 +1,11 @@
+// @strict: true
+/// <reference path='fourslash.ts' />
+//// function f(x: [|never?|]) {
+//// }
+
+verify.codeFix({
+    description: "Change 'never?' to 'never'",
+    errorCode: 17019,
+    index: 0,
+    newRangeContent: "never",
+});

tests/cases/fourslash/codeFixChangeJSDocSyntax28.ts

@@ -0,0 +1,11 @@
+// @strict: true
+/// <reference path='fourslash.ts' />
+//// function f(x: [|void?|]) {
+//// }
+
+verify.codeFix({
+    description: "Change 'void?' to 'void'",
+    errorCode: 17019,
+    index: 0,
+    newRangeContent: "void",
+});

tests/cases/fourslash/codeFixChangeJSDocSyntax5.ts

@@ -3,8 +3,8 @@
 //// var x: [|?number|] = 12;
 
 verify.codeFix({
-    description: "Change '?number' to 'number | null'",
-    errorCode: 8020,
+    description: "Change '?number' to 'number | null | undefined'",
+    errorCode: 17020,
     index: 0,
-    newRangeContent: "number | null",
+    newRangeContent: "number | null | undefined",
 });

tests/cases/fourslash/codeFixChangeJSDocSyntax6.ts

@@ -3,7 +3,7 @@
 //// var x: [|number?|] = 12;
 
 verify.codeFix({
-    description: "Change 'number?' to 'number | null | undefined'",
+    description: "Change 'number?' to 'number | undefined'",
     index: 1,
-    newRangeContent: "number | null | undefined",
+    newRangeContent: "number | undefined",
 });

tests/cases/fourslash/codeFixChangeJSDocSyntax_all.ts

@@ -6,5 +6,5 @@
 verify.codeFixAll({
 	fixId: "fixJSDocTypes_plain",
 	fixAllDescription: "Change all jsdoc-style types to TypeScript",
-	newFileContent: "function f(a: number | null, b: string) {}",
+	newFileContent: "function f(a: number | null | undefined, b: string) {}",
 })