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TypeError when using async/await with nested promises in a Vue component

👀 Views: 271 đŸ’Ŧ Answers: 1 📅 Created: 2025-06-07
vue async-await promises JavaScript

I'm working with a `TypeError: want to read property 'value' of undefined` when trying to await a nested promise inside a method in my Vue component. The method is supposed to fetch data from an API and then transform that data to set a reactive property. Here's how my method looks: ```javascript methods: { async fetchData() { try { const response = await this.$http.get('/api/data'); const transformedData = await this.transformData(response.data); this.myData = transformedData; } catch (behavior) { console.behavior('behavior fetching data:', behavior); } }, async transformData(data) { return new Promise((resolve, reject) => { // Simulating an asynchronous operation setTimeout(() => { if (data) { resolve(data.map(item => item.value)); } else { reject('No data provided'); } }, 1000); }); } }, ``` When I call `fetchData`, it seems to work fine until it reaches the line `resolve(data.map(item => item.value));`. If the `data` is an empty array, it throws the TypeError, which I wasn't expecting. I checked and confirmed that the API returns an empty array, but I thought the map function would handle that gracefully. I'm not sure how to prevent this behavior from occurring when the data is empty. I tried adding a check for empty data before calling `map`, but it didn't solve the scenario. Any insight on how to handle this correctly would be greatly appreciated! The stack includes Javascript and several other technologies. What would be the recommended way to handle this?