DEV: deepMerge and deepEqual functions (#10764)

app/assets/javascripts/discourse-common/addon/lib/object.js

@@ -0,0 +1,55 @@
+function isObject(obj) {
+  return obj && typeof obj === "object";
+}
+
+// a fairly simple deep merge based on: https://gist.github.com/ahtcx/0cd94e62691f539160b32ecda18af3d6
+export function deepMerge(...objects) {
+  function deepMergeInner(target, source) {
+    Object.keys(source).forEach((key) => {
+      const targetValue = target[key];
+      const sourceValue = source[key];
+
+      if (Array.isArray(targetValue) && Array.isArray(sourceValue)) {
+        target[key] = targetValue.concat(sourceValue);
+      } else if (isObject(targetValue) && isObject(sourceValue)) {
+        target[key] = deepMergeInner(
+          Object.assign({}, targetValue),
+          sourceValue
+        );
+      } else {
+        target[key] = sourceValue;
+      }
+    });
+
+    return target;
+  }
+
+  if (objects.some((object) => object && !isObject(object))) {
+    throw new Error('deepMerge: all values should be of type "object"');
+  }
+
+  const target = objects.shift();
+  let source;
+
+  while ((source = objects.shift())) {
+    deepMergeInner(target, source || {});
+  }
+
+  return target;
+}
+
+export function deepEqual(obj1, obj2) {
+  if (obj1 === obj2) {
+    return true;
+  } else if (isObject(obj1) && isObject(obj2)) {
+    if (Object.keys(obj1).length !== Object.keys(obj2).length) {
+      return false;
+    }
+    for (var prop in obj1) {
+      if (!deepEqual(obj1[prop], obj2[prop])) {
+        return false;
+      }
+    }
+    return true;
+  }
+}