Don't create test file in build directory

Author: fzhinkin

core/common/test/files/SmokeFileTest.kt

@@ -9,10 +9,21 @@ import kotlinx.io.*
 import kotlin.test.*
 
 class SmokeFileTest {
+    private var tempFile: String? = null
+
+    @BeforeTest
+    fun setup() {
+        tempFile = createTempFile()
+    }
+
+    @AfterTest
+    fun cleanup() {
+        deleteFile(tempFile!!)
+    }
 
     @Test
     fun testBasicFile() {
-        val path = Path("test.txt")
+        val path = Path(tempFile!!)
         path.sink().use {
             it.writeUtf8("example")
         }

core/common/test/util.kt

@@ -102,3 +102,6 @@ fun bufferWithSegments(vararg segments: String): Buffer {
 //  b: Path,
 //  sameAsNio: Boolean = true,
 //): IllegalArgumentException
+
+expect fun createTempFile(): String
+expect fun deleteFile(path: String)

core/jvm/test/ultil.kt

@@ -0,0 +1,16 @@
+/*
+ * Copyright 2017-2023 JetBrains s.r.o. and respective authors and developers.
+ * Use of this source code is governed by the Apache 2.0 license that can be found in the LICENCE file.
+ */
+package kotlinx.io
+
+import java.nio.file.*
+
+actual fun createTempFile(): String = Files.createTempFile(null, null).toString()
+
+actual fun deleteFile(path: String) {
+    if (!Files.isRegularFile(Paths.get(path))) {
+        throw IllegalArgumentException("Path is not a file: $path.")
+    }
+    Files.delete(Paths.get(path))
+}

core/native/src/files/PathsNative.kt

@@ -21,13 +21,13 @@ public actual fun Path(path: String): Path = Path(path, null)
 
 public actual fun Path.source(): Source {
     val openFile: CPointer<FILE> = fopen(path, "r")
-        ?: throw IOException("Failed to open $path with $errno")
+        ?: throw IOException("Failed to open $path with ${strerror(errno)?.toKString()}")
     return FileSource(openFile).buffer()
 }
 
 public actual fun Path.sink(): Sink {
-    val openFile: CPointer<FILE> = fopen(path, "wx")
-        ?: throw IOException("Failed to open $path with $errno")
+    val openFile: CPointer<FILE> = fopen(path, "w")
+        ?: throw IOException("Failed to open $path with ${strerror(errno)?.toKString()}")
     return FileSink(openFile).buffer()
 }
 

core/native/test/util.kt

@@ -0,0 +1,21 @@
+/*
+ * Copyright 2017-2023 JetBrains s.r.o. and respective authors and developers.
+ * Use of this source code is governed by the Apache 2.0 license that can be found in the LICENCE file.
+ */
+package kotlinx.io
+
+import kotlinx.cinterop.*
+import platform.posix.*
+
+actual fun createTempFile(): String {
+    val template = "tmp-XXXXXX"
+    val path = mktemp(template.cstr) ?: throw IOException("Filed to create temp file: ${strerror(errno)}")
+    return path.toKString()
+}
+
+actual fun deleteFile(path: String) {
+    if (access(path, F_OK) != 0) throw IOException("File does not exist: $path")
+    if (remove(path) != 0) {
+        throw IOException("Failed to delete file $path: ${strerror(errno)}")
+    }
+}