test: Attempt to fix InvalidWatchKeyException test

TODO.md

@@ -8,11 +8,14 @@
 ## Medium Projects
 
 * [ ] Figure out how to use newer versions of GraalVM on all platforms for the JS parser.
-* [ ] Finish and test the comment writer functionality from PR 48.
-* [ ] Add test coverage for any other code that isn't already covered.
+* [ ] Write tests:
+  * [ ] PR #48 (write descriptions as comments in exported config values)
+  * [ ] File watcher on Windows/Linux (inc. `InvalidWatchKeyException`)
+  * [ ] Description of required, optional, and lazy config items
+  * [ ] Other random areas that aren't explicitly listed in this
 
 ## Large Projects
 
 * [ ] Move all configuration format parsers to KotlinX Serialization instead of a mix of Jackson modules and various
       third-party parsers.
-  * This would enable use of Konf on Kotlin Multiplatform projects!
+  * This could help enable use of Konf on Kotlin Multiplatform projects, but it would be extremely challenging.

settings.gradle.kts

@@ -40,19 +40,22 @@ develocity {
 dependencyResolutionManagement {
     versionCatalogs {
         create("libs") {
+            // Shared versions
             version("jackson", "2.17.1")
             // WARNING!
             // Don't upgrade the GraalVM dependency version!
             // The newer versions have different coordinates and a bunch of unusual issues.
             // There is no documented fix on non-Graal JDKs.
             version("graal", "22.3.5")
 
+            // Gradle plugins
             plugin("dokka", "org.jetbrains.dokka").version("1.9.20")
             plugin("kover", "org.jetbrains.kotlinx.kover").version("0.8.0")
             plugin("benchmark", "org.jetbrains.kotlinx.benchmark").version("0.4.10")
             plugin("sonatype-publisher", "net.thebugmc.gradle.sonatype-central-portal-publisher").version("1.2.3")
             plugin("solo-publisher", "ca.solo-studios.sonatype-publish").version("0.1.3")
 
+            // Dependencies
             library("kotlinx-coroutines-core", "org.jetbrains.kotlinx", "kotlinx-coroutines-core").version("1.8.1")
             library("reflections", "org.reflections", "reflections").version("0.10.2")
             library("commons-text", "org.apache.commons", "commons-text").version("1.12.0")
@@ -69,11 +72,16 @@ dependencyResolutionManagement {
             library("dom4j", "org.dom4j", "dom4j").version("2.1.4")
             library("jaxen", "jaxen", "jaxen").version("2.0.0")
             library("snakeyaml", "org.yaml", "snakeyaml").version("2.2")
+
+            // Test dependencies
             library("junit-params", "org.junit.jupiter", "junit-jupiter-params").version("5.10.2")
             library("spark", "com.sparkjava", "spark-core").version("2.9.4")
             library("slf4j-simple", "org.slf4j", "slf4j-simple").version("2.0.13")
+
+            // Benchmark dependencies
             library("kotlinx-benchmark-runtime", "org.jetbrains.kotlinx", "kotlinx-benchmark-runtime").version("0.4.10")
 
+            // Library bundles
             bundle("jackson", listOf("jackson-core", "jackson-annotations", "jackson-databind", "jackson-kotlin", "jackson-jsr310"))
             bundle("graal", listOf("graal-sdk", "graal-js"))
         }

src/test/kotlin/io/github/nhubbard/konf/TestInvalidWatchKey.kt

@@ -18,10 +18,13 @@
 package io.github.nhubbard.konf
 
 import io.github.nhubbard.konf.helpers.InvalidWatchKey
-import org.junit.jupiter.api.AfterAll
+import kotlinx.coroutines.MainScope
+import kotlinx.coroutines.delay
+import kotlinx.coroutines.launch
+import org.junit.jupiter.api.BeforeAll
 import org.junit.jupiter.api.Test
 import org.junit.jupiter.api.TestInstance
-import java.nio.file.Paths
+import java.util.concurrent.TimeUnit
 import kotlin.io.path.deleteIfExists
 import kotlin.io.path.writeText
 
@@ -34,24 +37,33 @@ class TestInvalidWatchKey {
     |  "second": "test_data"
     |}
     """.trimMargin()
-    private val inputFile = Paths.get("src/test/resources/invalid_watch.json")
+    private val inputFile = tempFileOf(input, suffix = ".json").toPath()
+
+    @BeforeAll
+    fun preTestSetup() {
+        inputFile.writeText(input)
+    }
 
     @Test
     fun testWatchKey_onBecomingInvalid_itThrows() {
+        // This test does not cover the correct branches on macOS
         if ("mac" !in System.getProperty("os.name").lowercase()) {
             // Write valid test data to input file
             inputFile.writeText(input)
             // Open valid data
-            Config {
+            val config = Config {
                 addSpec(InvalidWatchKey)
-            }.from.json.watchFile(inputFile.toFile())
-            // Overwrite the file with invalid data
-            inputFile.writeText("asofidmaposidfmpoasimdf")
+            }.from.json.watchFile(inputFile.toFile(), delayTime = 50, unit = TimeUnit.MILLISECONDS)
+            // Make watch key invalid???
+            inputFile.deleteIfExists()
+            // Wait for several seconds...
+            MainScope().launch {
+                delay(10000)
+                println(config[InvalidWatchKey.first])
+                println(config[InvalidWatchKey.second])
+            }
+            // Attempt to access invalid value???
+            config[InvalidWatchKey.second]
         }
     }
-
-    @AfterAll
-    fun postTestCleanup() {
-        inputFile.deleteIfExists()
-    }
 }