From dc80e6a28b693ca9d8406a4618d7fa4723a0aa95 Mon Sep 17 00:00:00 2001
From: Oleksandr T <oleksandr.tarasiuk@outlook.com>
Date: Tue, 17 Aug 2021 03:20:40 +0300
Subject: [PATCH] feat(18147): skip uncessary parenthesis (#44769)

---
 src/services/refactors/extractSymbol.ts   |  4 ++--
 tests/cases/fourslash/extract-const8.ts   | 14 ++++++++++++++
 tests/cases/fourslash/extract-const9.ts   | 14 ++++++++++++++
 tests/cases/fourslash/extract-method42.ts | 21 +++++++++++++++++++++
 tests/cases/fourslash/extract-method43.ts | 21 +++++++++++++++++++++
 5 files changed, 72 insertions(+), 2 deletions(-)
 create mode 100644 tests/cases/fourslash/extract-const8.ts
 create mode 100644 tests/cases/fourslash/extract-const9.ts
 create mode 100644 tests/cases/fourslash/extract-method42.ts
 create mode 100644 tests/cases/fourslash/extract-method43.ts

diff --git a/src/services/refactors/extractSymbol.ts b/src/services/refactors/extractSymbol.ts
index 8ffc1646c47..6490fde5387 100644
--- a/src/services/refactors/extractSymbol.ts
+++ b/src/services/refactors/extractSymbol.ts
@@ -1141,7 +1141,7 @@ namespace ts.refactor.extractSymbol {
             ? undefined
             : checker.typeToTypeNode(checker.getContextualType(node)!, scope, NodeBuilderFlags.NoTruncation); // TODO: GH#18217
 
-        let initializer = transformConstantInitializer(node, substitutions);
+        let initializer = transformConstantInitializer(skipParentheses(node), substitutions);
 
         ({ variableType, initializer } = transformFunctionInitializerAndType(variableType, initializer));
 
@@ -1375,7 +1375,7 @@ namespace ts.refactor.extractSymbol {
         }
         let returnValueProperty: string | undefined;
         let ignoreReturns = false;
-        const statements = factory.createNodeArray(isBlock(body) ? body.statements.slice(0) : [isStatement(body) ? body : factory.createReturnStatement(body as Expression)]);
+        const statements = factory.createNodeArray(isBlock(body) ? body.statements.slice(0) : [isStatement(body) ? body : factory.createReturnStatement(skipParentheses(body as Expression))]);
         // rewrite body if either there are writes that should be propagated back via return statements or there are substitutions
         if (hasWritesOrVariableDeclarations || substitutions.size) {
             const rewrittenStatements = visitNodes(statements, visitor).slice();
diff --git a/tests/cases/fourslash/extract-const8.ts b/tests/cases/fourslash/extract-const8.ts
new file mode 100644
index 00000000000..5c72bd82e18
--- /dev/null
+++ b/tests/cases/fourslash/extract-const8.ts
@@ -0,0 +1,14 @@
+/// <reference path='fourslash.ts' />
+
+// @filename: foo.ts
+////const foo = 1 * /*a*/(2 + 2)/*b*/;
+
+goTo.select("a", "b");
+edit.applyRefactor({
+    refactorName: "Extract Symbol",
+    actionName: "constant_scope_0",
+    actionDescription: "Extract to constant in enclosing scope",
+    newContent:
+`const newLocal = 2 + 2;
+const foo = 1 * /*RENAME*/newLocal;`
+});
diff --git a/tests/cases/fourslash/extract-const9.ts b/tests/cases/fourslash/extract-const9.ts
new file mode 100644
index 00000000000..b575d227967
--- /dev/null
+++ b/tests/cases/fourslash/extract-const9.ts
@@ -0,0 +1,14 @@
+/// <reference path='fourslash.ts' />
+
+// @filename: foo.ts
+////const foo = 1 * /*a*/(((((2 + 2)))))/*b*/;
+
+goTo.select("a", "b");
+edit.applyRefactor({
+    refactorName: "Extract Symbol",
+    actionName: "constant_scope_0",
+    actionDescription: "Extract to constant in enclosing scope",
+    newContent:
+`const newLocal = 2 + 2;
+const foo = 1 * /*RENAME*/newLocal;`
+});
diff --git a/tests/cases/fourslash/extract-method42.ts b/tests/cases/fourslash/extract-method42.ts
new file mode 100644
index 00000000000..b22dc145f81
--- /dev/null
+++ b/tests/cases/fourslash/extract-method42.ts
@@ -0,0 +1,21 @@
+/// <reference path='fourslash.ts' />
+
+////function foo() {
+////	const x = 10 * /*a*/(10 + 10)/*b*/;
+////}
+
+goTo.select("a", "b");
+edit.applyRefactor({
+    refactorName: "Extract Symbol",
+    actionName: "function_scope_1",
+    actionDescription: "Extract to function in global scope",
+    newContent:
+`function foo() {
+	const x = 10 * /*RENAME*/newFunction();
+}
+
+function newFunction() {
+    return 10 + 10;
+}
+`
+});
diff --git a/tests/cases/fourslash/extract-method43.ts b/tests/cases/fourslash/extract-method43.ts
new file mode 100644
index 00000000000..8deb93f4765
--- /dev/null
+++ b/tests/cases/fourslash/extract-method43.ts
@@ -0,0 +1,21 @@
+/// <reference path='fourslash.ts' />
+
+////function foo() {
+////	const x = 10 * /*a*/((((((10 + 10))))))/*b*/;
+////}
+
+goTo.select("a", "b");
+edit.applyRefactor({
+    refactorName: "Extract Symbol",
+    actionName: "function_scope_1",
+    actionDescription: "Extract to function in global scope",
+    newContent:
+`function foo() {
+	const x = 10 * /*RENAME*/newFunction();
+}
+
+function newFunction() {
+    return 10 + 10;
+}
+`
+});