[Refactor] improve performance of rule merging

jsx-eslint · May 2, 2022 · 1db241c · 1db241c
1 parent c8833f3
commit 1db241c
Showing 1 changed file with 43 additions and 32 deletions.
diff --git a/lib/util/Components.js b/lib/util/Components.js
@@ -247,6 +247,40 @@ function getWrapperFunctions(context, pragma) {
   ]);
 }
 
+// eslint-disable-next-line valid-jsdoc
+/**
+ * Merge many eslint rules into one
+ * @param {{[_: string]: Function}[]} rules the returned values for eslint rule.create(context)
+ * @returns {{[_: string]: Function}} merged rule
+ */
+function mergeRules(rules) {
+  /** @type {Map<string, Function[]>} */
+  const handlersByKey = new Map();
+  for (const rule of rules) {
+    for (const key of Object.keys(rule)) {
+      const fns = handlersByKey.get(key);
+      if (!fns) {
+        handlersByKey.set(key, [rule[key]]);
+      } else {
+        fns.push(rule[key]);
+      }
+    }
+  }
+
+  /** @type {{[key: string]: Function}} */
+  const rule = {};
+  for (const key of handlersByKey.keys()) {
+    const fns = handlersByKey.get(key);
+    rule[key] = function mergedHandler(node) {
+      for (const fn of fns) {
+        fn(node);
+      }
+    };
+  }
+
+  return rule;
+}
+
 function componentRule(rule, context) {
   const pragma = pragmaUtil.getFromContext(context);
   const sourceCode = context.getSourceCode();
@@ -859,44 +893,21 @@ function componentRule(rule, context) {
     },
   };
 
-  // Update the provided rule instructions to add the component detection
   const ruleInstructions = rule(context, components, utils);
-  const updatedRuleInstructions = Object.assign({}, ruleInstructions);
   const propTypesInstructions = propTypesUtil(context, components, utils);
   const usedPropTypesInstructions = usedPropTypesUtil(context, components, utils);
   const defaultPropsInstructions = defaultPropsUtil(context, components, utils);
-  const allKeys = new Set(Object.keys(detectionInstructions).concat(
-    Object.keys(propTypesInstructions),
-    Object.keys(usedPropTypesInstructions),
-    Object.keys(defaultPropsInstructions),
-    Object.keys(reactImportInstructions)
-  ));
 
-  allKeys.forEach((instruction) => {
-    updatedRuleInstructions[instruction] = (node) => {
-      if (instruction in detectionInstructions) {
-        detectionInstructions[instruction](node);
-      }
-      if (instruction in propTypesInstructions) {
-        propTypesInstructions[instruction](node);
-      }
-      if (instruction in usedPropTypesInstructions) {
-        usedPropTypesInstructions[instruction](node);
-      }
-      if (instruction in defaultPropsInstructions) {
-        defaultPropsInstructions[instruction](node);
-      }
-      if (instruction in reactImportInstructions) {
-        reactImportInstructions[instruction](node);
-      }
-      if (ruleInstructions[instruction]) {
-        return ruleInstructions[instruction](node);
-      }
-    };
-  });
+  const mergedRule = mergeRules([
+    detectionInstructions,
+    propTypesInstructions,
+    usedPropTypesInstructions,
+    defaultPropsInstructions,
+    reactImportInstructions,
+    ruleInstructions,
+  ]);
 
-  // Return the updated rule instructions
-  return updatedRuleInstructions;
+  return mergedRule;
 }
 
 module.exports = Object.assign(Components, {