src/main/kotlin/filesystem/FSCreator.kt

@@ -2,10 +2,8 @@ package filesystem
 
 import java.nio.file.FileAlreadyExistsException
 import java.nio.file.FileSystemException
+import java.nio.file.Files
 import java.nio.file.Path
-import kotlin.io.path.createDirectory
-import kotlin.io.path.createFile
-import kotlin.io.path.writeText
 
 class FSCreator {
     /**
@@ -24,13 +22,13 @@ class FSCreator {
             val path = dest.resolve(entry.name)
             try {
                 when (entry) {
-                    is FSFile -> path.createFile()
-                    is FSFolder -> path.createDirectory()
+                    is FSFile -> Files.createFile(path)
+                    is FSFolder -> Files.createDirectory(path)
                 }
             } catch (_: FileAlreadyExistsException) {
             } // Allow files/folders to already exist.
             when (entry) {
-                is FSFile -> path.writeText(entry.content)
+                is FSFile -> Files.write(path, entry.content.toByteArray())
                 is FSFolder -> queue.addAll(entry.entries.map { it to path })
             }
         }

src/main/kotlin/filesystem/FSEntry.kt

@@ -1,21 +1,9 @@
 package filesystem
 
-import kotlin.io.path.Path
-
 // Note sealed allows for simpler logic in FSCreator by guaranteeing FSFile and FSFolder are the only possible FSEntries
 // (as we expect), and it also implicitly makes the class abstract as required.
-sealed class FSEntry(val name: String) {
-    init {
-        val p = Path(name)
-        // Only allow single filenames (no paths or relative references (e.g. ".."))
-        if (p.toList().size != 1 || p.fileName != p.toFile().canonicalFile.toPath().fileName) {
-            throw InvalidEntryNameException(name)
-        }
-    }
-}
+sealed class FSEntry(val name: String)
 
 class FSFile(name: String, val content: String) : FSEntry(name)
 
 class FSFolder(name: String, val entries: List<FSEntry>) : FSEntry(name)
-
-class InvalidEntryNameException(name: String) : Exception("Invalid FSEntry name: '$name'")

src/test/kotlin/filesystem/FSCreatorTest.kt

@@ -1,11 +1,10 @@
 package filesystem
 
 import org.junit.jupiter.api.*
-import java.io.File
 import java.nio.file.FileSystemException
+import java.nio.file.Files
+import java.nio.file.Path
 import java.util.concurrent.TimeUnit
-import kotlin.io.path.Path
-import kotlin.io.path.createDirectory
 import kotlin.test.Test
 import kotlin.test.assertEquals
 
@@ -15,26 +14,17 @@ class FSCreatorTest {
     @BeforeEach
     fun `before each`() {
         assertDoesNotThrow("should create _tmp directory") {
-            Path("_tmp").createDirectory()
+            Files.createDirectory(Path.of("_tmp"))
         }
     }
 
     @AfterEach
     fun `after each`() {
         assertDoesNotThrow("should delete _tmp directory") {
-            File("_tmp").deleteRecursively()
+            deleteRecursive(Path.of("_tmp"))
         }
     }
 
-    @Test
-    fun `create file`() {
-        val file = FSFile("test.txt", "This is a file")
-        assertDoesNotThrow("should create file") {
-            creator.create(file, "_tmp")
-        }
-        assertEquals(file.content, File("_tmp/", file.name).readText())
-    }
-
     @Test
     fun `create entries`() {
         val readme = FSFile("README", "Hello World!")
@@ -72,10 +62,10 @@ class FSCreatorTest {
         }
         // If objects don't exist, these functions will throw anyway, so don't explicitly check for existence.
         // Similarly, don't explicitly check if an object is a directory.
-        assertEquals(readme.content, File("_tmp/folder", readme.name).readText())
-        assertEquals(gomod.content, File("_tmp/folder", gomod.name).readText())
-        assertEquals(maingo.content, File("_tmp/folder", maingo.name).readText())
-        assertEquals(helloworldgo.content, File("_tmp/folder/utils", helloworldgo.name).readText())
+        assertEquals(readme.content, Files.readString(Path.of("_tmp/folder", readme.name)))
+        assertEquals(gomod.content, Files.readString(Path.of("_tmp/folder", gomod.name)))
+        assertEquals(maingo.content, Files.readString(Path.of("_tmp/folder", maingo.name)))
+        assertEquals(helloworldgo.content, Files.readString(Path.of("_tmp/folder/utils", helloworldgo.name)))
     }
 
     @Test
@@ -122,11 +112,11 @@ class FSCreatorTest {
                 "_tmp",
             )
         }
-        assertEquals("hi", File("_tmp/folder/sub-folder/hi").readText())
-        assertEquals("P4ssW0rd", File("_tmp/folder/another-folder/secrets/secret").readText())
-        assertEquals("One is a good number", File("_tmp/folder/1.txt").readText())
-        assertEquals("Two!", File("_tmp/folder/2.txt").readText())
-        assertEquals("Three!", File("_tmp/folder/3.txt").readText())
+        assertEquals("hi", Files.readString(Path.of("_tmp/folder/sub-folder/hi")))
+        assertEquals("P4ssW0rd", Files.readString(Path.of("_tmp/folder/another-folder/secrets/secret")))
+        assertEquals("One is a good number", Files.readString(Path.of("_tmp/folder/1.txt")))
+        assertEquals("Two!", Files.readString(Path.of("_tmp/folder/2.txt")))
+        assertEquals("Three!", Files.readString(Path.of("_tmp/folder/3.txt")))
     }
 
     @Test
@@ -140,3 +130,12 @@ class FSCreatorTest {
         }
     }
 }
+
+fun deleteRecursive(path: Path) {
+    if (Files.isDirectory(path)) {
+        for (child in Files.list(path)) {
+            deleteRecursive(child)
+        }
+    }
+    Files.delete(path)
+}