feature: @putout/operator-parens: addParens/removeParens: do nothingh when parens exists/absent

Author: coderaiser

packages/operator-parens/lib/parens.js

@@ -6,20 +6,14 @@ const {
     TSParenthesizedType,
 } = types;
 
-module.exports.hasParens = (path) => {
-    const printer = getPrinter(path);
-    
-    if (printer !== 'babel')
-        return path.node.extra?.parenthesized;
-    
-    const {type} = path.parentPath;
-    
-    return /^(TS)?Parenthesized(Expression|Type)?$/.test(type);
-};
+module.exports.hasParens = hasParens;
 
 module.exports.addParens = (path) => {
     const printer = getPrinter(path);
 
+    if (hasParens(path, printer))
+        return path;
+    
     if (printer !== 'babel') {
         const {extra = {}} = path.node;
 
@@ -42,6 +36,9 @@ module.exports.addParens = (path) => {
 module.exports.removeParens = (path) => {
     const printer = getPrinter(path);
 
+    if (!hasParens(path, printer))
+        return path;
+    
     if (printer !== 'babel') {
         path.node.extra.parenthesized = false;
         return path;
@@ -59,3 +56,12 @@ function getPrinter(path) {
 
     return programPath.node.extra.__putout_printer;
 }
+
+function hasParens(path, printer = getPrinter(path)) {
+    if (printer !== 'babel')
+        return path.node.extra?.parenthesized;
+    
+    const {type} = path.parentPath;
+    
+    return /^(TS)?Parenthesized(Expression|Type)?$/.test(type);
+}

packages/operator-parens/lib/parens.spec.js

@@ -69,6 +69,29 @@ test('putout: operator: parens: removeParens: babel', (t) => {
     t.end();
 });
 
+test('putout: operator: parens: removeParens: babel: no parens', (t) => {
+    const source = 'b = 3';
+    const ast = parse(source, {
+        printer: 'babel',
+    });
+    
+    traverse(ast, {
+        NumericLiteral(path) {
+            removeParens(path);
+            path.stop();
+        },
+    });
+    
+    const result = print(ast, {
+        printer: 'babel',
+    });
+    
+    const expected = 'b = 3;\n';
+    
+    t.equal(result, expected);
+    t.end();
+});
+
 test('putout: operator: parens: removeParens: babel: return', (t) => {
     const source = '(b = 3)';
     const ast = parse(source, {
@@ -145,6 +168,29 @@ test('putout: operator: parens: addParens: babel', (t) => {
     t.end();
 });
 
+test('putout: operator: parens: addParens: babel: has parens', (t) => {
+    const source = '(b = 3)';
+    const ast = parse(source, {
+        printer: 'babel',
+    });
+    
+    traverse(ast, {
+        AssignmentExpression(path) {
+            addParens(path);
+            path.stop();
+        },
+    });
+    
+    const result = print(ast, {
+        printer: 'babel',
+    });
+    
+    const expected = '(b = 3);\n';
+    
+    t.equal(result, expected);
+    t.end();
+});
+
 test('putout: operator: parens: addParens: babel: return', (t) => {
     const source = 'b = 3';
     const ast = parse(source, {