Eager t.* access in shouldStoreRHSInTemporaryVariable (#14191)

zhangenming · web-flow · commit e9756cb958ce · 2022-02-13T15:48:49.000+01:00
diff --git a/packages/babel-plugin-proposal-object-rest-spread/src/shouldStoreRHSInTemporaryVariable.ts b/packages/babel-plugin-proposal-object-rest-spread/src/shouldStoreRHSInTemporaryVariable.ts
@@ -1,6 +1,13 @@
 import { types as t } from "@babel/core";
 
-const { isObjectProperty } = t;
+const {
+  isObjectProperty,
+  isArrayPattern,
+  isObjectPattern,
+  isAssignmentPattern,
+  isRestElement,
+  isIdentifier,
+} = t;
 /**
  * This is a helper function to determine if we should create an intermediate variable
  * such that the RHS of an assignment is not duplicated.
@@ -9,11 +16,11 @@ const { isObjectProperty } = t;
  * on further optimizations.
  */
 export default function shouldStoreRHSInTemporaryVariable(node: t.LVal) {
-  if (t.isArrayPattern(node)) {
+  if (isArrayPattern(node)) {
     const nonNullElements = node.elements.filter(element => element !== null);
     if (nonNullElements.length > 1) return true;
     else return shouldStoreRHSInTemporaryVariable(nonNullElements[0]);
-  } else if (t.isObjectPattern(node)) {
+  } else if (isObjectPattern(node)) {
     const { properties } = node;
     if (properties.length > 1) return true;
     else if (properties.length === 0) return false;
@@ -26,10 +33,10 @@ export default function shouldStoreRHSInTemporaryVariable(node: t.LVal) {
         return shouldStoreRHSInTemporaryVariable(firstProperty);
       }
     }
-  } else if (t.isAssignmentPattern(node)) {
+  } else if (isAssignmentPattern(node)) {
     return shouldStoreRHSInTemporaryVariable(node.left);
-  } else if (t.isRestElement(node)) {
-    if (t.isIdentifier(node.argument)) return true;
+  } else if (isRestElement(node)) {
+    if (isIdentifier(node.argument)) return true;
     return shouldStoreRHSInTemporaryVariable(node.argument);
   } else {
     // node is Identifier or MemberExpression
