Print parens for nodes with extra.parenthesized

Fixes benjamn#705
conartist6 · May 25, 2020 · 17b85de · 17b85de
1 parent 1d920ae
commit 17b85de
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Showing 3 changed files with 21 additions and 15 deletions.
diff --git a/lib/fast-path.ts b/lib/fast-path.ts
@@ -329,7 +329,7 @@ FPp.needsParens = function (assumeExpressionContext) {
     return false;
   }
 
-  if (parent.type === 'ParenthesizedExpression') {
+  if (parent.type === 'ParenthesizedExpression' || (node.extra && node.extra.parenthesized)) {
     return false;
   }
 

diff --git a/lib/printer.ts b/lib/printer.ts
@@ -192,14 +192,14 @@ function genericPrint(path: any, config: any, options: any, printPath: any) {
     return linesWithoutParens;
   }
 
-  let shouldAddParens = false;
+  let shouldAddParens = node.extra ? node.extra.parenthesized : false;
   const decoratorsLines = printDecorators(path, printPath);
 
   if (decoratorsLines.isEmpty()) {
     // Nodes with decorators can't have parentheses, so we can avoid
     // computing path.needsParens() except in this case.
     if (!options.avoidRootParens) {
-      shouldAddParens = path.needsParens();
+      shouldAddParens = shouldAddParens || path.needsParens();
     }
   } else {
     parts.push(decoratorsLines);
@@ -1969,11 +1969,8 @@ function genericPrintNoParens(path: any, options: any, print: any) {
       return concat([path.call(print, 'left'), '.', path.call(print, 'right')]);
 
     case 'TSAsExpression': {
-      const withParens = n.extra && n.extra.parenthesized === true;
-      if (withParens) parts.push('(');
       const expression = path.call(print, 'expression');
       parts.push(expression, fromString(' as '), path.call(print, 'typeAnnotation'));
-      if (withParens) parts.push(')');
 
       return concat(parts);
     }
@@ -2099,17 +2096,8 @@ function genericPrintNoParens(path: any, options: any, print: any) {
     }
 
     case 'TSTypeAssertion': {
-      const withParens = n.extra && n.extra.parenthesized === true;
-      if (withParens) {
-        parts.push('(');
-      }
-
       parts.push('<', path.call(print, 'typeAnnotation'), '> ', path.call(print, 'expression'));
 
-      if (withParens) {
-        parts.push(')');
-      }
-
       return concat(parts);
     }
 

diff --git a/test/parens-babylon.ts b/test/parens-babylon.ts
@@ -37,4 +37,22 @@ describe('babylon parens', function () {
   it('YieldExpression', function () {
     check('(function* () { return {...(yield obj)}})');
   });
+
+  it('decorative parens', function () {
+    const ast = parse('1');
+    const expr = ast.program.body[0].expression;
+
+    expr.extra.parenthesized = true;
+
+    assert.strictEqual(printer.print(ast).code, '(1)');
+  });
+
+  it('decorative parens which are also necessary', function () {
+    const ast = parse('(1).foo');
+    const expr = ast.program.body[0].expression;
+
+    expr.object.extra.parenthesized = false;
+
+    assert.strictEqual(printer.print(ast).code, '(1).foo');
+  });
 });