Meituan-Dianping/mpvue · warning

v-on without argument expects an Object value

Error message

v-on without argument expects an Object value

What it means

`bindObjectListeners` implements `v-on="value"` without an argument, which merges a plain object of `{ eventName: handler }` into the vnode's `on` data. If the value is truthy but not a plain object, Vue warns because listeners cannot be derived from it.

Source

Thrown at packages/weex-vue-framework/factory.js:4013

      }
    }
  } else {
    markStaticNode(tree, key, isOnce);
  }
}

function markStaticNode (node, key, isOnce) {
  node.isStatic = true;
  node.key = key;
  node.isOnce = isOnce;
}

/*  */

function bindObjectListeners (data, value) {
  if (value) {
    if (!isPlainObject(value)) {
      process.env.NODE_ENV !== 'production' && warn(
        'v-on without argument expects an Object value',
        this
      );
    } else {
      var on = data.on = data.on ? extend({}, data.on) : {};
      for (var key in value) {
        var existing = on[key];
        var ours = value[key];
        on[key] = existing ? [].concat(ours, existing) : ours;
      }
    }
  }
  return data
}

/*  */

function initRender (vm) {

View on GitHub (pinned to 6c5d78ee04)

Solutions

1. Bind a plain object of handlers: `v-on="{ click: onClick, input: onInput }"`.
2. Convert to a plain object: `v-on="{ ...listenerMap }"` or build it in a computed returning a fresh `{}`.
3. If a single handler was intended, restore the argument: `v-on:click="fn"`.
4. Guard: `v-on="isPlainObj(h) ? h : {}"`.

Example fix

// before
<div v-on="handleClick" />
// after
<div v-on="{ click: handleClick }" />

if (listeners != null && (typeof listeners !== 'object' || Array.isArray(listeners) || listeners.constructor !== Object)) {
  throw new TypeError('v-on without argument requires a plain object of handlers');
}

function isListenerMap(v) {
  return v != null && typeof v === 'object' && !Array.isArray(v) && Object.getPrototypeOf(v) === Object.prototype;
}

When it happens

Trigger: `<div v-on="someArray">` or `v-on="handlerFn"` (a function, not an object of handlers); passing a reactive/non-plain object (e.g. a class instance or observed object) to `v-on`; `v-on="cond && handlers"` where the truthy branch isn't a plain object.

Common situations: Migrating from `v-on:click="fn"` by deleting the argument; spreading listener maps stored in Vuex (observed objects); passing class-instance event maps from TypeScript code.

Related errors

• Use "contextmenu" instead of "click.right" since right click
• v-bind without argument expects an Object or Array value
• tag <${tag}> has no matching end tag.
• passive and prevent can't be used together. Passive handler
• Templates should only be responsible for mapping the state t

AI-assisted analysis of Meituan-Dianping/mpvue@6c5d78ee04 (2026-09-02). Data as JSON: /api/errors/d7c1a1805518703b. Report an issue: GitHub.