Adds com.soywiz.korio.test.assertEqualsJvmFileReference (#495)

It uses dynamic access to assertEquals,
to not require including kotlin-test or create separate artifacts
just for this testing tool

build.gradle.kts

@@ -187,21 +187,17 @@ subprojects {
         afterEvaluate {
             val jvmTest = tasks.findByName("jvmTest")
             if (jvmTest is org.jetbrains.kotlin.gradle.targets.jvm.tasks.KotlinJvmTest) {
-                val jvmTestFix = tasks.create("jvmTestFix", Test::class)
-                jvmTestFix.group = "verification"
-                //jvmTestFix.group = jvmTest.group
-                jvmTestFix.environment("UPDATE_TEST_REF", "true")
-                jvmTestFix.testClassesDirs = jvmTest.testClassesDirs
-                jvmTestFix.classpath = jvmTest.classpath
-                jvmTestFix.bootstrapClasspath = jvmTest.bootstrapClasspath
-                if (!beforeJava9) {
-                    jvmTest.jvmArgs(*javaAddOpens)
-                    jvmTestFix.jvmArgs(*javaAddOpens)
-                }
-                if (headlessTests) {
-                    jvmTest.systemProperty("java.awt.headless", "true")
-                    jvmTestFix.systemProperty("java.awt.headless", "true")
+                val jvmTestFix = tasks.create("jvmTestFix", Test::class) {
+                    group = "verification"
+                    environment("UPDATE_TEST_REF", "true")
+                    testClassesDirs = jvmTest.testClassesDirs
+                    classpath = jvmTest.classpath
+                    bootstrapClasspath = jvmTest.bootstrapClasspath
+                    if (!beforeJava9) jvmArgs(*javaAddOpens)
+                    if (headlessTests) systemProperty("java.awt.headless", "true")
                 }
+                if (!beforeJava9) jvmTest.jvmArgs(*javaAddOpens)
+                if (headlessTests) jvmTest.systemProperty("java.awt.headless", "true")
             }
         }
 

korge/src/jvmTest/kotlin/com/soywiz/korge/test/assertEqualsFileReference.kt

@@ -1,15 +1,8 @@
 package com.soywiz.korge.test
 
-import java.io.*
-import kotlin.test.*
+import com.soywiz.korio.test.*
 
 // Use ./gradlew jvmTestFix to update these files
 fun assertEqualsFileReference(path: String, content: String) {
-    val file = File("src/jvmTest/resources/$path").absoluteFile
-    if (System.getenv("UPDATE_TEST_REF") == "true") {
-        file.parentFile.mkdirs()
-        file.writeText(content)
-    }
-    //if (!file.exists()) assertTrue(false, "File '$file' doesn't exists")
-    assertEquals(file.takeIf { it.exists() }?.readText(), content)
+    assertEqualsJvmFileReference(path, content)
 }

korio/src/commonMain/kotlin/com/soywiz/korio/dynamic/Dyn.kt

@@ -169,6 +169,7 @@ inline class Dyn(val value: Any?) : Comparable<Dyn> {
 
     interface Invokable {
         fun invoke(name: String, args: Array<out Any?>): Any?
+        fun invokeOrThrow(name: String, args: Array<out Any?>): Any? = invoke(name, args)
     }
 
     interface SuspendInvokable {
@@ -181,6 +182,12 @@ inline class Dyn(val value: Any?) : Comparable<Dyn> {
         else -> dynApi.invoke(value, name, args).dyn
     }
 
+    fun dynamicInvokeOrThrow(name: String, vararg args: Any?): Dyn = when (value) {
+        null -> error("Can't invoke '$name' on null")
+        is Invokable -> value.invokeOrThrow(name, args).dyn
+        else -> dynApi.invokeOrThrow(value, name, args).dyn
+    }
+
     suspend fun suspendDynamicInvoke(name: String, vararg args: Any?): Dyn = when (value) {
         null -> null.dyn
         is Invokable -> value.invoke(name, args).dyn

korio/src/commonMain/kotlin/com/soywiz/korio/dynamic/DynApi.kt

@@ -8,6 +8,7 @@ interface DynApi {
     fun get(instance: Any?, key: String): Any?
     fun set(instance: Any?, key: String, value: Any?)
     fun invoke(instance: Any?, key: String, args: Array<out Any?>): Any?
+    fun invokeOrThrow(instance: Any?, key: String, args: Array<out Any?>): Any? = invoke(instance, key, args)
 
     suspend fun suspendGet(instance: Any?, key: String): Any? = get(instance, key)
     suspend fun suspendSet(instance: Any?, key: String, value: Any?): Unit = set(instance, key, value)

korio/src/jvmAndroidMain/kotlin/com/soywiz/korio/dynamic/DynApiJvm.kt

@@ -86,9 +86,28 @@ internal actual object DynamicInternal : DynApi {
     }
 
     override fun invoke(instance: Any?, key: String, args: Array<out Any?>): Any? {
-        if (instance == null) return null
+        return invokeBase(instance, key, args, doThrow = false)
+    }
+
+    override fun invokeOrThrow(instance: Any?, key: String, args: Array<out Any?>): Any? {
+        return invokeBase(instance, key, args, doThrow = true)
+    }
+
+    fun invokeBase(instance: Any?, key: String, args: Array<out Any?>, doThrow: Boolean): Any? {
+        if (instance == null) {
+            if (doThrow) error("Can't invoke '$key' on null")
+            return null
+        }
         val method = tryGetMethod(if (instance is Class<*>) instance else instance.javaClass, key, args)
-        return method?.invoke(if (instance is Class<*>) null else instance, *args)
+        if (method == null) {
+            if (doThrow) error("Can't find method '$key' on ${instance::class}")
+            return null
+        }
+        return try {
+            method.invoke(if (instance is Class<*>) null else instance, *args)
+        } catch (e: InvocationTargetException) {
+            throw e.targetException ?: e
+        }
     }
 }
 

korio/src/jvmMain/kotlin/com/soywiz/korio/test/assertEqualsJvmFileReference.kt

@@ -0,0 +1,46 @@
+package com.soywiz.korio.test
+
+import com.soywiz.korio.dynamic.*
+import java.io.*
+
+/**
+ * Checks that a string matches a file in `src/jvmTest/resources`.
+ * When environment variable UPDATE_TEST_REF=true, instead of checking,
+ * this functions updates the file with the expected content.
+ *
+ * This is similar to jest's snapshot testing: <https://jestjs.io/docs/snapshot-testing>
+ *
+ * ---
+ *
+ * To simplify its usage, it is recommended to define a `jvmTestFix` gradle task as follows:
+ *
+ * Use ./gradlew jvmTestFix to update these files
+ *
+ * jvmTestFix gradle task should add environment("UPDATE_TEST_REF", "true")
+ *
+ * ```kotlin
+ * val jvmTestFix = tasks.create("jvmTestFix", Test::class) {
+ *     group = "verification"
+ *     environment("UPDATE_TEST_REF", "true")
+ *     testClassesDirs = jvmTest.testClassesDirs
+ *     classpath = jvmTest.classpath
+ *     bootstrapClasspath = jvmTest.bootstrapClasspath
+ *     systemProperty("java.awt.headless", "true")
+ * }
+ * ```
+ */
+fun assertEqualsJvmFileReference(path: String, content: String) {
+    val file = File("src/jvmTest/resources/$path").absoluteFile
+    if (System.getenv("UPDATE_TEST_REF") == "true") {
+        file.parentFile.mkdirs()
+        file.writeText(content)
+    }
+
+    val message: String? = null
+    val expected: String = file.takeIf { it.exists() }?.readText() ?: ""
+    val actual: String = content
+
+    Dyn.global["kotlin.test.AssertionsKt"]
+        .dynamicInvokeOrThrow("getAsserter")
+        .dynamicInvokeOrThrow("assertEquals", message, expected, actual)
+}