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TypeError: Cannot read property 'slice' of undefined

オープン
  • 何か問題がありますか？
#112 コメント 2 件 リアクション 0 件 担当者 0 名 GitHub で見る

まだ誰も着手していません。

評価

難易度
3/5
見積もり時間
1〜2日
初心者へのやさしさ
30/100
issue の種類
バグ
明瞭さ
説明が足りない
活発さ
停滞
技術スタック
react-native, typescript
領域
mobile

調査の方向性

まず、示されているポイントデータを使って CurrencyScreen のエラーを再現し、次にスタックトレースに記載されている LineGraphImpl と AnimatedLineGraph への呼び出しを追跡します。どの undefined 値が slice 呼び出しに到達するのかを特定し、通貨画面で報告されたエラーが発生しなくなったことを確認します。

索引モデルが issue の本文から書いたものです。

説明

export default function CurrencyScreen({ navigation, route }: CurrencyScreenProps) {

    const { id } = route.params

    const [dates, setDates] = useState<IValuteShowRequest>({
        start_date: convertDateToString(
            new Date(new Date().setDate(new Date().getDate() - 10))
        ),
        end_date: convertDateToString(new Date())
    })

    const { data, isLoading, error } = useGetValuteQuery({
        id,
        body: dates
    });

    const preparedData = data?.data

    const points = preparedData?.positions.map(position => {
        return {
            value: position.value,
            date: parseDateFromString(position.date)
        }
    })

    // const switchDate = (pos: 'start_date' | "end_date", date: Date) => {
    //     setDates(prev => { return { ...prev, [pos]: convertDateToString(date) } })
    // }

    if (isLoading) {
        return <Loading />
    }

    if (error) {
        return <Error />
    }

    return (
        <View style={baseStyles.wrapper}>
            <ScrollView style={baseStyles.scrollView}>
                {points && <LineGraph color={Colors.blue500} animated={true} points={points} />}
            </ScrollView>
        </View>
    );
}

ERROR  TypeError: Cannot read property 'slice' of undefined

This error is located at:
    in AnimatedLineGraph (created by LineGraphImpl)
    in LineGraphImpl (created by CurrencyScreen)
    in RCTView (created by View)
    in View (created by ScrollView)
    in RCTScrollView (created by ScrollView)
    in ScrollView (created by ScrollView)
    in ScrollView (created by CurrencyScreen)
    in RCTView (created by View)
    in View (created by CurrencyScreen)
    in CurrencyScreen (created by SceneView)
    in StaticContainer
    in EnsureSingleNavigator (created by SceneView)
    in SceneView (created by SceneView)
    in RCTView (created by View)
    in View (created by DebugContainer)
    in DebugContainer (created by MaybeNestedStack)
    in MaybeNestedStack (created by SceneView)
    in RCTView (created by View)
    in View (created by SceneView)
    in RNSScreen (created by Animated(Anonymous))
    in Animated(Anonymous) (created by InnerScreen)
    in Suspender (created by Freeze)
    in Suspense (created by Freeze)
    in Freeze (created by DelayedFreeze)
    in DelayedFreeze (created by InnerScreen)
    in InnerScreen (created by Screen)
    in Screen (created by SceneView)
    in SceneView (created by NativeStackViewInner)
    in Suspender (created by Freeze)
    in Suspense (created by Freeze)
    in Freeze (created by DelayedFreeze)
    in DelayedFreeze (created by ScreenStack)
    in RNSScreenStack (created by ScreenStack)
    in ScreenStack (created by NativeStackViewInner)
    in NativeStackViewInner (created by NativeStackView)
    in RCTView (created by View)
    in View (created by SafeAreaProviderCompat)
    in SafeAreaProviderCompat (created by NativeStackView)
    in NativeStackView (created by NativeStackNavigator)
    in PreventRemoveProvider (created by NavigationContent)
    in NavigationContent
    in Unknown (created by NativeStackNavigator)
    in NativeStackNavigator (created by Router)
    in Router (created by App)
    in AuthProvider (created by App)
    in NotifProvider (created by App)
    in EnsureSingleNavigator
    in BaseNavigationContainer
    in ThemeProvider
    in NavigationContainerInner (created by App)
    in RCTView (created by View)
    in View (created by App)
    in ThemeProvider (created by PaperProvider)
    in RCTView (created by View)
    in View (created by Portal.Host)
    in Portal.Host (created by PaperProvider)
    in RNCSafeAreaProvider (created by SafeAreaProvider)
    in SafeAreaProvider (created by SafeAreaInsetsContext)
    in SafeAreaProviderCompat (created by PaperProvider)
    in PaperProvider (created by App)
    in Provider (created by App)
    in App (created by withDevTools(App))
    in withDevTools(App)
    in RCTView (created by View)
    in View (created by AppContainer)
    in RCTView (created by View)
    in View (created by AppContainer)
    in AppContainer
    in main(RootComponent), js engine: hermes
主要言語
TypeScript
スター
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フォーク
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平均マージ
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マージ済み PR（30日）
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環境構築

はじめの一歩

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  3. リポジトリをフォークし、ブランチを切って変更します。
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