Error: typescript doesn't type infer switch statement

microsoft/TypeScript#37178
letwebdev · Sep 16, 2023 · 5def84a · 5def84a
1 parent c936b34
commit 5def84a
Showing 1 changed file with 37 additions and 30 deletions.
diff --git a/src/views/HackerNewsView.vue b/src/views/HackerNewsView.vue
@@ -13,6 +13,7 @@ interface List {
   readonly description: string
 }
 type Lists = List[]
+type LiveData = number | number[] | object
 interface Item {
   readonly by: string
   readonly id: number
@@ -71,40 +72,46 @@ function fetchItems(listName: string = "topstories") {
         throw new Error(`HTTP error: ${response.status}`)
       }
     })
-    .then((liveData: number | number[] | object) => {
+    .then((liveData: LiveData) => {
       console.log("Type of liveData is " + typeof liveData)
-      if (typeof liveData === "number") {
-        console.log("Live data is currently largest item id: " + liveData)
-        const maxItemId: number = liveData
-        const randomItemId = generateRandomInteger(maxItemId)
-        fetchItem(randomItemId)
-      } else if (Array.isArray(liveData)) {
-        console.log("Live data is an array ")
-        let itemIds: number[]
-        if (settings.fetchingRandomly.enabled) {
-          const idsGenerantedRandomly: number[] = []
-          // TODO array.length may be less than maximumDisplayedItemsPerPage
-          for (let i = 0; i < settings.maximumDisplayedItemsPerPage.value; i++) {
-            const randomArrayIndex = generateRandomInteger(liveData.length - 1)
-            const idToPush = liveData[randomArrayIndex]
-            // Prevent duplicate id
-            if (idToPush === idsGenerantedRandomly[-1]) {
-              i--
-              continue
-            } else {
-              idsGenerantedRandomly.push(idToPush)
+      switch (true) {
+        case typeof liveData === "number": {
+          console.log("Live data is currently largest item id: " + liveData)
+          const maxItemId: number = liveData
+          const randomItemId = generateRandomInteger(maxItemId)
+          fetchItem(randomItemId)
+          break
+        }
+        case Array.isArray(liveData): {
+          console.log("Live data is an array ")
+          let itemIds: number[]
+          if (settings.fetchingRandomly.enabled) {
+            const idsGenerantedRandomly: number[] = []
+            // TODO array.length may be less than maximumDisplayedItemsPerPage
+            for (let i = 0; i < settings.maximumDisplayedItemsPerPage.value; i++) {
+              const randomArrayIndex = generateRandomInteger(liveData.length - 1)
+              const idToPush = liveData[randomArrayIndex]
+              // Prevent duplicate id
+              if (idToPush === idsGenerantedRandomly[-1]) {
+                i--
+                continue
+              } else {
+                idsGenerantedRandomly.push(idToPush)
+              }
             }
+            itemIds = [...idsGenerantedRandomly]
+          } else {
+            itemIds = [...liveData]
           }
-          itemIds = [...idsGenerantedRandomly]
-        } else {
-          itemIds = [...liveData]
+          itemIds.forEach((itemId) => {
+            fetchItem(itemId)
+          })
+          promptForFetching.value = ""
+          break
+        }
+        default: {
+          console.log("Unknwon live data type")
         }
-        itemIds.forEach((itemId) => {
-          fetchItem(itemId)
-        })
-        promptForFetching.value = ""
-      } else {
-        console.log("Unknwon live data type")
       }
     })
     .catch((error) => console.error(`Error fetching data: ${error.message}`))