[FIX] Prevent multiple deletes being called

Author: c-py

one-way-data-binding-library.mjs

@@ -17,21 +17,23 @@ export default (bindings) => {
       matchedBy.forEach((match) => {
         // No binding exists for this key; bind and call create method
         if (!(key in bound)) {
-          nextBound[key] = { methods: bindings[match](), data };
-          if (nextBound[key].methods.create) {
-            nextBound[key].methods.create(data, state);
+          bound[key] = { methods: bindings[match](), data };
+          if (bound[key].methods.create) {
+            bound[key].methods.create(data, state);
           }
         }
         // Binding exists and data reference has changed; call update method
         else if (bound[key].methods.update && data !== bound[key].data) {
-          nextBound[key] = { methods: bound[key].methods, data };
-          nextBound[key].methods.update(data, state);
+          bound[key].methods.update(data, state);
         }
+
+        nextBound[key] = { methods: bound[key].methods, data };
       });
     });
 
     Object.keys(bound).forEach((key) => {
       if (!(key in nextBound) || nextBound[key] === undefined) {
+        console.log("delete", key);
         bound[key].methods.delete?.(state);
       }
     });

one-way-data-binding-library.test.mjs

@@ -254,4 +254,23 @@ describe("one-way-data-binding-library", () => {
 
     expect(runs).toBe(1);
   });
+
+  it("runs a single delete on popping a list", () => {
+    let runs = 0;
+
+    const foo = () => ({
+      delete: () => runs++,
+    });
+
+    const run = bind({
+      "state.foo[*]": foo,
+    });
+
+    run(() => ({ state: { foo: [1, 2, 3] } }));
+    run((state) => {
+      state.state.foo.pop();
+    });
+
+    expect(runs).toBe(1);
+  });
 });