Bypassing cancellation errors

Refs: #48
motorro · Sep 29, 2023 · 7a672d4 · 7a672d4
1 parent 215ccc5
commit 7a672d4
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Showing 5 changed files with 41 additions and 6 deletions.
diff --git a/coroutines/src/commonMain/kotlin/com/motorro/rxlcemodel/coroutines/CacheThenNetLceModel.kt b/coroutines/src/commonMain/kotlin/com/motorro/rxlcemodel/coroutines/CacheThenNetLceModel.kt
@@ -21,6 +21,7 @@ import com.motorro.rxlcemodel.common.Logger
 import com.motorro.rxlcemodel.coroutines.service.ServiceSet
 import com.motorro.rxlcemodel.lce.LceState
 import com.motorro.rxlcemodel.lce.LceState.*
+import coroutinesRunCatching
 import kotlinx.coroutines.*
 import kotlinx.coroutines.flow.*
 
@@ -104,7 +105,7 @@ class CacheThenNetLceModel<DATA: Any, PARAMS: Any>(
                         type = if (null == data) Loading.Type.LOADING else Loading.Type.REFRESHING
                     )
                 )
-                runCatching { loadAndCacheNetwork() }.onFailure { error ->
+                coroutinesRunCatching { loadAndCacheNetwork() }.onFailure { error ->
                     if (error !is CancellationException) {
                         withLogger {
                             modelLog(WARNING, "Error getting data from network - ERROR: $error")

diff --git a/coroutines/src/commonMain/kotlin/com/motorro/rxlcemodel/coroutines/UpdateWrapper.kt b/coroutines/src/commonMain/kotlin/com/motorro/rxlcemodel/coroutines/UpdateWrapper.kt
@@ -22,6 +22,7 @@ import com.motorro.rxlcemodel.common.UpdateOperationState
 import com.motorro.rxlcemodel.common.UpdateOperationState.*
 import com.motorro.rxlcemodel.coroutines.service.CacheService
 import com.motorro.rxlcemodel.lce.LceState
+import coroutinesRunCatching
 import kotlinx.coroutines.CoroutineDispatcher
 import kotlinx.coroutines.ExperimentalCoroutinesApi
 import kotlinx.coroutines.flow.*
@@ -55,15 +56,15 @@ abstract class UpdateWrapper<DATA: Any, PARAMS: Any>(
      */
     protected suspend fun doUpdate(dataSource: suspend (params: PARAMS) -> Entity<DATA>) {
         networkOperationState.emit(LOADING)
-        try {
+        coroutinesRunCatching {
             withContext(ioDispatcher) {
                 withLogger { modelLog(INFO, "Subscribing network...") }
                 val data = dataSource(params)
                 withLogger { modelLog(INFO, "Saving to cache...") }
                 cacheService.save(params, data)
             }
             networkOperationState.emit(IDLE)
-        } catch (error: Throwable) {
+        }.onFailure { error ->
             withLogger { modelLog(WARNING, "Network error: $error") }
             networkOperationState.emit(ERROR(error))
         }

diff --git a/coroutines/src/commonMain/kotlin/com/motorro/rxlcemodel/coroutines/coroutines.kt b/coroutines/src/commonMain/kotlin/com/motorro/rxlcemodel/coroutines/coroutines.kt
@@ -0,0 +1,15 @@
+import kotlinx.coroutines.CancellationException
+
+/**
+ * Calls the specified function [block] with `this` value as its receiver and returns its encapsulated result if invocation was successful,
+ * catching any [Throwable] exception besides [CancellationException] that was thrown from the [block] function execution and encapsulating it as a failure.
+ */
+public inline fun <T, R> T.coroutinesRunCatching(block: T.() -> R): Result<R> {
+    return try {
+        Result.success(block())
+    } catch (c: CancellationException) {
+        throw c
+    } catch (e: Throwable) {
+        Result.failure(e)
+    }
+}
diff --git a/coroutines/src/commonMain/kotlin/com/motorro/rxlcemodel/coroutines/lceUtils.kt b/coroutines/src/commonMain/kotlin/com/motorro/rxlcemodel/coroutines/lceUtils.kt
@@ -16,6 +16,7 @@ package com.motorro.rxlcemodel.coroutines
 import com.motorro.rxlcemodel.lce.LceState
 import com.motorro.rxlcemodel.lce.combine
 import com.motorro.rxlcemodel.lce.map
+import coroutinesRunCatching
 import kotlinx.coroutines.ExperimentalCoroutinesApi
 import kotlinx.coroutines.flow.*
 
@@ -117,9 +118,7 @@ fun <DATA_1: Any, DATA_2: Any> Flow<LceState<DATA_1>>.flatMapSingleData(mapper:
 
     suspend fun stateMapper(data1: DATA_1?): LceState<DATA_2> = when(data1) {
         null -> LceState.Loading(null, false)
-        else -> try {
-            LceState.Content(mapper(data1), true)
-        } catch (e: Throwable) {
+        else -> coroutinesRunCatching { LceState.Content(mapper(data1), true) }.getOrElse { e ->
             LceState.Error(null, false, e)
         }
     }

diff --git a/coroutines/src/commonTest/kotlin/com/motorro/rxlcemodel/coroutines/LceUtilsKtTest.kt b/coroutines/src/commonTest/kotlin/com/motorro/rxlcemodel/coroutines/LceUtilsKtTest.kt
@@ -14,6 +14,7 @@
 package com.motorro.rxlcemodel.coroutines
 
 import com.motorro.rxlcemodel.lce.LceState
+import kotlinx.coroutines.CancellationException
 import kotlinx.coroutines.ExperimentalCoroutinesApi
 import kotlinx.coroutines.flow.*
 import kotlinx.coroutines.launch
@@ -22,6 +23,7 @@ import kotlinx.coroutines.test.runTest
 import kotlin.test.Test
 import kotlin.test.assertEquals
 import kotlin.test.assertFailsWith
+import kotlin.test.assertTrue
 
 @OptIn(ExperimentalCoroutinesApi::class)
 class LceUtilsKtTest {
@@ -247,6 +249,23 @@ class LceUtilsKtTest {
         )
     }
 
+    @Test
+    fun singleDataMapperBypassesCancellationExceptions() = runTest {
+        val error1 = Exception("error 1")
+        val error2 = CancellationException("Cancelled")
+
+        @Suppress("UNUSED_PARAMETER")
+        fun mapper(input: Int): String = throw error2
+
+        val source = flowOf(
+            LceState.Loading(null, false),
+            LceState.Content(2, true)
+        )
+
+        val result = source.flatMapSingleData(::mapper).toList()
+        assertEquals(1, result.size)
+    }
+
     @Test
     fun mapsUseCaseData() = runTest {
         val error = Exception()