Infer type from assertion for export assignment.

Author: dragomirtitian

src/compiler/transformers/declarations.ts

@@ -1529,7 +1529,8 @@ export function transformDeclarations(context: TransformationContext) {
                         errorNode: input,
                     });
                     errorFallbackNode = input;
-                    const varDecl = factory.createVariableDeclaration(newId, /*exclamationToken*/ undefined, resolver.createTypeOfExpression(input.expression, input, declarationEmitNodeBuilderFlags, symbolTracker), /*initializer*/ undefined);
+                    const type = ensureType(input);
+                    const varDecl = factory.createVariableDeclaration(newId, /*exclamationToken*/ undefined, type, /*initializer*/ undefined);
                     errorFallbackNode = undefined;
                     const statement = factory.createVariableStatement(needsDeclare ? [factory.createModifier(SyntaxKind.DeclareKeyword)] : [], factory.createVariableDeclarationList([varDecl], NodeFlags.Const));
 

tests/baselines/reference/verbatim-declarations-assertions(strict=false).js

@@ -234,9 +234,7 @@ export declare class C {
     methodWithRequiredDefault(p: P, req: number): void;
     constructor(ctorField?: P);
 }
-declare const _default: {
-    name: string;
-};
+declare const _default: P;
 export default _default;
 //// [assertToTypeLiteral.d.ts]
 export declare let vLet: {} & {
@@ -277,7 +275,7 @@ export declare class C {
         name: string;
     });
 }
-declare const _default: {
+declare const _default: {} & {
     name: string;
 };
 export default _default;

tests/baselines/reference/verbatim-declarations-assertions(strict=true).js

@@ -238,9 +238,7 @@ export declare class C {
     } | undefined, req: number): void;
     constructor(ctorField?: P);
 }
-declare const _default: {
-    name: string;
-};
+declare const _default: P;
 export default _default;
 //// [assertToTypeLiteral.d.ts]
 export declare let vLet: {} & {
@@ -281,7 +279,7 @@ export declare class C {
         name: string;
     });
 }
-declare const _default: {
+declare const _default: {} & {
     name: string;
 };
 export default _default;