Replace opaque HCON merge values

Author: scriptogre

src/htmx.js

@@ -74,8 +74,8 @@ var htmx = (() => {
             for (let [key, val] of Object.entries(source)) {
                 if (['__proto__', 'constructor', 'prototype'].includes(key)) continue;
 
-                let sourceIsObject = val && typeof val === 'object' && !Array.isArray(val);
-                let targetIsObject = target[key] && typeof target[key] === 'object' && !Array.isArray(target[key]);
+                let sourceIsObject = val?.constructor === Object;
+                let targetIsObject = target[key]?.constructor === Object;
 
                 if (sourceIsObject && targetIsObject) {
                     HCON.merge(val, target[key]);

test/tests/unit/HCON.js

@@ -396,6 +396,12 @@ describe('HCON.merge unit tests', function() {
         assert.deepEqual(result.list, [3, 4])
     })
 
+    it('does not deep-merge non-plain objects (replaces them)', function () {
+        let signal = new AbortController().signal
+        let result = HCON.merge({ signal }, { signal: new AbortController().signal })
+        assert.strictEqual(result.signal, signal)
+    })
+
     // string source (auto-parse)
 
     it('parses an HCON string source', function () {