Add parenthesis around object inside of as (#1852)

Fixes #1851

src/fast-path.js

@@ -519,6 +519,9 @@ FastPath.prototype.needsParens = function() {
           return false;
       }
 
+    case "ObjectExpression":
+      return parent.type === "TSAsExpression";
+
     case "ClassExpression":
       return parent.type === "ExportDefaultDeclaration";
 

tests/typescript_as/__snapshots__/jsfmt.spec.js.snap

@@ -8,6 +8,7 @@ this.isTabActionBar((e.target || e.srcElement) as HTMLElement);
 start + (yearSelectTotal as number)
 scrollTop > (visibilityHeight as number)
 export default class Column<T> extends (RcTable.Column as React.ComponentClass<ColumnProps<T>>) {}
+({}) as {};
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 const name = (description as DescriptionObject).name || (description as string);
 this.isTabActionBar((e.target || e.srcElement) as HTMLElement);
@@ -20,5 +21,6 @@ scrollTop > (visibilityHeight as number);
 export default class Column<T> extends (RcTable.Column as React.ComponentClass<
   ColumnProps<T>
 >) {}
+({}) as {};
 
 `;

tests/typescript_as/as.js

@@ -5,3 +5,4 @@ this.isTabActionBar((e.target || e.srcElement) as HTMLElement);
 start + (yearSelectTotal as number)
 scrollTop > (visibilityHeight as number)
 export default class Column<T> extends (RcTable.Column as React.ComponentClass<ColumnProps<T>>) {}
+({}) as {};