Don't Debug.fail on TypeAssertionExpression in JS

Author: jakebailey

src/compiler/program.ts

@@ -2930,13 +2930,12 @@ export function createProgram(rootNamesOrOptions: readonly string[] | CreateProg
                         diagnostics.push(createDiagnosticForNode(node, Diagnostics.Non_null_assertions_can_only_be_used_in_TypeScript_files));
                         return "skip";
                     case SyntaxKind.AsExpression:
+                    case SyntaxKind.TypeAssertionExpression:
                         diagnostics.push(createDiagnosticForNode((node as AsExpression).type, Diagnostics.Type_assertion_expressions_can_only_be_used_in_TypeScript_files));
                         return "skip";
                     case SyntaxKind.SatisfiesExpression:
                         diagnostics.push(createDiagnosticForNode((node as SatisfiesExpression).type, Diagnostics.Type_satisfaction_expressions_can_only_be_used_in_TypeScript_files));
                         return "skip";
-                    case SyntaxKind.TypeAssertionExpression:
-                        Debug.fail(); // Won't parse these in a JS file anyway, as they are interpreted as JSX.
                 }
             }
 

tests/baselines/reference/typeAssertionExpressionInJsNoCrash.errors.txt

@@ -0,0 +1,15 @@
+tests/cases/compiler/index.js(2,18): error TS2352: Conversion of type 'string' to type 'number' may be a mistake because neither type sufficiently overlaps with the other. If this was intentional, convert the expression to 'unknown' first.
+tests/cases/compiler/index.js(2,18): error TS2703: The operand of a 'delete' operator must be a property reference.
+tests/cases/compiler/index.js(2,19): error TS8016: Type assertion expressions can only be used in TypeScript files.
+
+
+==== tests/cases/compiler/index.js (3 errors) ====
+    const x = "oops";
+    const y = delete <number> x;
+                     ~~~~~~~~~~
+!!! error TS2352: Conversion of type 'string' to type 'number' may be a mistake because neither type sufficiently overlaps with the other. If this was intentional, convert the expression to 'unknown' first.
+                     ~~~~~~~~~~
+!!! error TS2703: The operand of a 'delete' operator must be a property reference.
+                      ~~~~~~
+!!! error TS8016: Type assertion expressions can only be used in TypeScript files.
+    

tests/baselines/reference/typeAssertionExpressionInJsNoCrash.symbols

@@ -0,0 +1,8 @@
+=== tests/cases/compiler/index.js ===
+const x = "oops";
+>x : Symbol(x, Decl(index.js, 0, 5))
+
+const y = delete <number> x;
+>y : Symbol(y, Decl(index.js, 1, 5))
+>x : Symbol(x, Decl(index.js, 0, 5))
+

tests/baselines/reference/typeAssertionExpressionInJsNoCrash.types

@@ -0,0 +1,11 @@
+=== tests/cases/compiler/index.js ===
+const x = "oops";
+>x : "oops"
+>"oops" : "oops"
+
+const y = delete <number> x;
+>y : boolean
+>delete <number> x : boolean
+><number> x : number
+>x : "oops"
+