AppFile create, check existence, delete, works for android

composeApp/src/androidInstrumentedTest/kotlin/resources/CreatesAppFileTest.kt

@@ -0,0 +1,34 @@
+package resources
+
+import androidx.test.platform.app.InstrumentationRegistry
+import io.kotest.matchers.booleans.shouldBeFalse
+import io.kotest.matchers.booleans.shouldBeTrue
+import kotlin.test.AfterTest
+import kotlin.test.BeforeTest
+import kotlin.test.Test
+
+class CreatesAppFileTest {
+    val saveFile = AppFile("saveFile.json")
+
+    @BeforeTest
+    fun setup() {
+        AppFile.context = InstrumentationRegistry.getInstrumentation().targetContext
+        if(saveFile.exists()) {
+            saveFile.delete()
+        }
+    }
+
+    @AfterTest
+    fun teardown() {
+        if(saveFile.exists()) {
+            saveFile.delete()
+        }
+    }
+
+    @Test
+    fun createAppFile() {
+        saveFile.exists().shouldBeFalse()
+        saveFile.create().shouldBeTrue()
+        saveFile.exists().shouldBeTrue()
+    }
+}

composeApp/src/androidMain/kotlin/resources/AppFile.android.kt

@@ -1,16 +1,23 @@
 package resources
 
 @Suppress("EXPECT_ACTUAL_CLASSIFIERS_ARE_IN_BETA_WARNING")
-actual class AppFile actual constructor(fileName: String) {
+actual class AppFile actual constructor(val fileName: String) {
     actual fun exists(): Boolean {
-        TODO("Not yet implemented")
+        return context?.getFileStreamPath(fileName)?.exists() ?: false
     }
 
     actual fun create(): Boolean {
-        TODO("Not yet implemented")
+        return context?.openFileOutput(fileName, android.content.Context.MODE_PRIVATE)?.use {
+            it.write(byteArrayOf())
+            true
+        } ?: false
     }
 
     actual fun delete(): Boolean {
-        TODO("Not yet implemented")
+        return context?.deleteFile(fileName) ?: false
+    }
+
+    companion object {
+        var context: android.content.Context? = null
     }
 }