Rename js snippets

snippets/js/s/function-based-object-property-matches.md

@@ -0,0 +1,32 @@
+---
+title: Matches object properties based on function
+type: snippet
+language: javascript
+tags: [object]
+cover: watermelon-bike
+dateModified: 2020-10-21T21:54:53+03:00
+---
+
+Compares two objects to determine if the first one contains equivalent property values to the second one, based on a provided function.
+
+- Use `Object.keys()` to get all the keys of the second object.
+- Use `Array.prototype.every()`, `Object.prototype.hasOwnProperty()` and the provided function to determine if all keys exist in the first object and have equivalent values.
+- If no function is provided, the values will be compared using the equality operator.
+
+```js
+const matchesWith = (obj, source, fn) =>
+  Object.keys(source).every(key =>
+    obj.hasOwnProperty(key) && fn
+      ? fn(obj[key], source[key], key, obj, source)
+      : obj[key] == source[key]
+  );
+```
+
+```js
+const isGreeting = val => /^h(?:i|ello)$/.test(val);
+matchesWith(
+  { greeting: 'hello' },
+  { greeting: 'hi' },
+  (oV, sV) => isGreeting(oV) && isGreeting(sV)
+); // true
+```