Fix: false positive new with member in no-extra-parens (fixes #12740)

eslint · May 30, 2020 · ce6d5c5 · ce6d5c5
1 parent c29bd9f
commit ce6d5c5
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Showing 2 changed files with 49 additions and 4 deletions.
diff --git a/lib/rules/no-extra-parens.js b/lib/rules/no-extra-parens.js
@@ -687,6 +687,34 @@ module.exports = {
             reportsBuffer.reports = reportsBuffer.reports.filter(r => r.node !== node);
         }
 
+        /**
+         * Checks whether a node is a MemberExpression at NewExpression's callee.
+         * @param {ASTNode} node node to check.
+         * @returns {boolean} True if the node is a MemberExpression at NewExpression's callee. false otherwise.
+         */
+        function isMemberInNewCallee(node) {
+            if (node.type === "MemberExpression") {
+                return node.parent.type === "NewExpression" && node.parent.callee === node
+                    ? true
+                    : isMemberInNewCallee(node.parent);
+            }
+            return false;
+        }
+
+        /**
+         * Checks whether a MemberExpression node contains a CallExpression in member chaining.
+         * @param {ASTNode} node node to check
+         * @returns {boolean} True if the MemberExpression contains a CallExpression in member chaining. false otherwise.
+         */
+        function hasCallExpInMemberExp(node) {
+            if (node.type === "MemberExpression") {
+                return node.object.type === "CallExpression"
+                    ? true
+                    : hasCallExpInMemberExp(node.object);
+            }
+            return false;
+        }
+
         return {
             ArrayExpression(node) {
                 node.elements
@@ -927,7 +955,8 @@ module.exports = {
             LogicalExpression: checkBinaryLogical,
 
             MemberExpression(node) {
-                const nodeObjHasExcessParens = hasExcessParens(node.object);
+                const shouldAllowWrapOnce = isMemberInNewCallee(node) && hasCallExpInMemberExp(node);
+                const nodeObjHasExcessParens = shouldAllowWrapOnce ? hasDoubleExcessParens(node.object) : hasExcessParens(node.object);
 
                 if (
                     nodeObjHasExcessParens &&
@@ -946,8 +975,8 @@ module.exports = {
                 }
 
                 if (nodeObjHasExcessParens &&
-                  node.object.type === "CallExpression" &&
-                  node.parent.type !== "NewExpression") {
+                  node.object.type === "CallExpression"
+                ) {
                     report(node.object);
                 }
 

diff --git a/tests/lib/rules/no-extra-parens.js b/tests/lib/rules/no-extra-parens.js
@@ -589,7 +589,15 @@ ruleTester.run("no-extra-parens", rule, {
         "for (let a = b; a; a); a; a;",
         "for (a; a; a); a; a;",
         "for (; a; a); a; a;",
-        "for (let a = (b && c) === d; ;);"
+        "for (let a = (b && c) === d; ;);",
+
+        "new (a()).b.c;",
+        "new (a().b).c;",
+        "new (a().b.c);",
+        "new (a().b().d);",
+        "new a().b().d;",
+        "new (a(b()).c)",
+        "new (a.b()).c"
     ],
 
     invalid: [
@@ -741,6 +749,14 @@ ruleTester.run("no-extra-parens", rule, {
         invalid("((new A))()", "(new A)()", "NewExpression"),
         invalid("new (foo\n.baz\n.bar\n.foo.baz)", "new foo\n.baz\n.bar\n.foo.baz", "MemberExpression"),
         invalid("new (foo.baz.bar.baz)", "new foo.baz.bar.baz", "MemberExpression"),
+        invalid("new ((a.b())).c", "new (a.b()).c", "CallExpression"),
+        invalid("new ((a().b)).c", "new (a().b).c", "MemberExpression"),
+        invalid("new ((a().b().d))", "new (a().b().d)", "MemberExpression"),
+        invalid("new ((a())).b.d", "new (a()).b.d", "CallExpression"),
+        invalid("new (a.b).d;", "new a.b.d;", "MemberExpression"),
+        invalid("(a().b).d;", "a().b.d;", "MemberExpression"),
+        invalid("(a.b()).d;", "a.b().d;", "CallExpression"),
+        invalid("(a.b).d;", "a.b.d;", "MemberExpression"),
 
         invalid("0, (_ => 0)", "0, _ => 0", "ArrowFunctionExpression", 1),
         invalid("(_ => 0), 0", "_ => 0, 0", "ArrowFunctionExpression", 1),