Add Directory.list() to io.

src/cli/modules.c

@@ -7,6 +7,7 @@
 #include "scheduler.wren.inc"
 #include "timer.wren.inc"
 
+extern void directoryList(WrenVM* vm);
 extern void fileAllocate(WrenVM* vm);
 extern void fileFinalize(WrenVM* vm);
 extern void fileOpen(WrenVM* vm);
@@ -35,7 +36,7 @@ extern void timerStartTimer(WrenVM* vm);
 // If you add a new class to the largest module below, make sure to bump this.
 // Note that it also includes an extra slot for the sentinel value indicating
 // the end of the list.
-#define MAX_CLASSES_PER_MODULE 3
+#define MAX_CLASSES_PER_MODULE 4
 
 // Describes one foreign method in a class.
 typedef struct
@@ -87,6 +88,9 @@ typedef struct
 static ModuleRegistry modules[] =
 {
   MODULE(io)
+    CLASS(Directory)
+      STATIC_METHOD("list_(_,_)", directoryList)
+    END_CLASS
     CLASS(File)
       STATIC_METHOD("<allocate>", fileAllocate)
       STATIC_METHOD("<finalize>", fileFinalize)

src/module/io.c

@@ -46,6 +46,96 @@ void ioShutdown()
   shutdownStdin();
 }
 
+// If [request] failed with an error, sends the runtime error to the VM and
+// frees the request.
+//
+// Returns true if an error was reported.
+static bool handleRequestError(uv_fs_t* request)
+{
+  if (request->result >= 0) return false;
+  
+  FileRequestData* data = (FileRequestData*)request->data;
+  WrenValue* fiber = (WrenValue*)data->fiber;
+  
+  schedulerResumeError(fiber, uv_strerror((int)request->result));
+  
+  free(data);
+  uv_fs_req_cleanup(request);
+  free(request);
+  return true;
+}
+
+// Allocates a new request that resumes [fiber] when it completes.
+uv_fs_t* createRequest(WrenValue* fiber)
+{
+  uv_fs_t* request = (uv_fs_t*)malloc(sizeof(uv_fs_t));
+  
+  FileRequestData* data = (FileRequestData*)malloc(sizeof(FileRequestData));
+  data->fiber = fiber;
+  
+  request->data = data;
+  return request;
+}
+
+// Releases resources used by [request].
+//
+// Returns the fiber that should be resumed after [request] completes.
+WrenValue* freeRequest(uv_fs_t* request)
+{
+  FileRequestData* data = (FileRequestData*)request->data;
+  WrenValue* fiber = data->fiber;
+  
+  free(data);
+  uv_fs_req_cleanup(request);
+  free(request);
+  
+  return fiber;
+}
+
+static void directoryListCallback(uv_fs_t* request)
+{
+  if (handleRequestError(request)) return;
+
+  uv_dirent_t entry;
+
+  // TODO: Right now, there's way to create a list using the C API so create a
+  // buffer containing all of the result paths terminated by '\0'. We'll split
+  // that back into a list in Wren.
+  size_t resultLength = 0;
+  size_t bufferSize = 1024;
+  char* result = (char*)malloc(bufferSize);
+  
+  while (uv_fs_scandir_next(request, &entry) != UV_EOF)
+  {
+    size_t length = strlen(entry.name);
+    
+    // Grow the buffer if needed.
+    while (resultLength + length + 1 > bufferSize)
+    {
+      bufferSize *= 2;
+      result = realloc(result, bufferSize);
+    }
+    
+    // Copy the path, including the null terminator.
+    memcpy(result + resultLength, entry.name, length + 1);
+    resultLength += length + 1;
+  }
+  
+  WrenValue* fiber = freeRequest(request);
+  schedulerResumeBytes(fiber, result, resultLength);
+  free(result);
+}
+
+void directoryList(WrenVM* vm)
+{
+  const char* path = wrenGetArgumentString(vm, 1);
+  
+  uv_fs_t* request = createRequest(wrenGetArgumentValue(vm, 2));
+  
+  // TODO: Check return.
+  uv_fs_scandir(getLoop(), request, path, 0, directoryListCallback);
+}
+
 void fileAllocate(WrenVM* vm)
 {
   // Store the file descriptor in the foreign data, so that we can get to it
@@ -66,59 +156,12 @@ void fileFinalize(WrenVM* vm)
   uv_fs_req_cleanup(&request);
 }
 
-// If [request] failed with an error, sends the runtime error to the VM and
-// frees the request.
-//
-// Returns true if an error was reported.
-static bool handleRequestError(uv_fs_t* request)
-{
-  if (request->result >= 0) return false;
-  
-  FileRequestData* data = (FileRequestData*)request->data;
-  WrenValue* fiber = (WrenValue*)data->fiber;
-
-  schedulerResumeError(fiber, uv_strerror((int)request->result));
-
-  free(data);
-  uv_fs_req_cleanup(request);
-  free(request);
-  return true;
-}
-
-// Allocates a new request that resumes [fiber] when it completes.
-uv_fs_t* createRequest(WrenValue* fiber)
-{
-  uv_fs_t* request = (uv_fs_t*)malloc(sizeof(uv_fs_t));
-
-  FileRequestData* data = (FileRequestData*)malloc(sizeof(FileRequestData));
-  data->fiber = fiber;
-
-  request->data = data;
-  return request;
-}
-
-// Releases resources used by [request].
-//
-// Returns the fiber that should be resumed after [request] completes.
-WrenValue* freeRequest(uv_fs_t* request)
-{
-  FileRequestData* data = (FileRequestData*)request->data;
-  WrenValue* fiber = data->fiber;
-
-  free(data);
-  uv_fs_req_cleanup(request);
-  free(request);
-
-  return fiber;
-}
-
-static void openCallback(uv_fs_t* request)
+static void fileOpenCallback(uv_fs_t* request)
 {
   if (handleRequestError(request)) return;
   
   double fd = (double)request->result;
   WrenValue* fiber = freeRequest(request);
-  
   schedulerResumeDouble(fiber, fd);
 }
 
@@ -128,17 +171,16 @@ void fileOpen(WrenVM* vm)
   uv_fs_t* request = createRequest(wrenGetArgumentValue(vm, 2));
   
   // TODO: Allow controlling flags and modes.
-  uv_fs_open(getLoop(), request, path, O_RDONLY, 0, openCallback);
+  uv_fs_open(getLoop(), request, path, O_RDONLY, 0, fileOpenCallback);
 }
 
 // Called by libuv when the stat call for size completes.
-static void sizeCallback(uv_fs_t* request)
+static void fileSizeCallback(uv_fs_t* request)
 {
   if (handleRequestError(request)) return;
   
   double size = (double)request->statbuf.st_size;
   WrenValue* fiber = freeRequest(request);
-  
   schedulerResumeDouble(fiber, size);
 }
 
@@ -146,10 +188,10 @@ void fileSizePath(WrenVM* vm)
 {
   const char* path = wrenGetArgumentString(vm, 1);
   uv_fs_t* request = createRequest(wrenGetArgumentValue(vm, 2));
-  uv_fs_stat(getLoop(), request, path, sizeCallback);
+  uv_fs_stat(getLoop(), request, path, fileSizeCallback);
 }
 
-static void closeCallback(uv_fs_t* request)
+static void fileCloseCallback(uv_fs_t* request)
 {
   if (handleRequestError(request)) return;
   
@@ -173,7 +215,7 @@ void fileClose(WrenVM* vm)
   *foreign = -1;
   
   uv_fs_t* request = createRequest(wrenGetArgumentValue(vm, 1));
-  uv_fs_close(getLoop(), request, fd, closeCallback);
+  uv_fs_close(getLoop(), request, fd, fileCloseCallback);
   wrenReturnBool(vm, false);
 }
 
@@ -226,7 +268,7 @@ void fileSize(WrenVM* vm)
   int fd = *(int*)wrenGetArgumentForeign(vm, 0);
   // TODO: Assert fd != -1.
   
-  uv_fs_fstat(getLoop(), request, fd, sizeCallback);
+  uv_fs_fstat(getLoop(), request, fd, fileSizeCallback);
 }
 
 static void allocCallback(uv_handle_t* handle, size_t suggestedSize,

src/module/io.wren

@@ -1,5 +1,37 @@
 import "scheduler" for Scheduler
 
+class Directory {
+  static list(path) {
+    if (!(path is String)) Fiber.abort("Path must be a string.")
+
+    list_(path, Fiber.current)
+
+    // We get back a byte array containing all of the paths, each terminated by
+    // a zero byte.
+    var entryBuffer = Scheduler.runNextScheduled_()
+
+    // TODO: Add split() to String.
+    // Split it into an array of strings.
+    var entries = []
+    var start = 0
+    var i = 0
+    var bytes = entryBuffer.bytes
+    while (i < bytes.count) {
+      if (bytes[i] == 0) {
+        var entry = entryBuffer[start...i]
+        start = i + 1
+        entries.add(entry)
+      }
+
+      i = i + 1
+    }
+
+    return entries
+  }
+
+  foreign static list_(path, fiber)
+}
+
 foreign class File {
   static open(path) {
     if (!(path is String)) Fiber.abort("Path must be a string.")
@@ -90,6 +122,7 @@ class Stdin {
       readStop_()
 
       if (__line != null) {
+        // Emit the last line.
         var line = __line
         __line = null
         if (__waitingFiber != null) __waitingFiber.transfer(line)

src/module/io.wren.inc

@@ -2,6 +2,38 @@
 static const char* ioModuleSource =
 "import \"scheduler\" for Scheduler\n"
 "\n"
+"class Directory {\n"
+"  static list(path) {\n"
+"    if (!(path is String)) Fiber.abort(\"Path must be a string.\")\n"
+"\n"
+"    list_(path, Fiber.current)\n"
+"\n"
+"    // We get back a byte array containing all of the paths, each terminated by\n"
+"    // a zero byte.\n"
+"    var entryBuffer = Scheduler.runNextScheduled_()\n"
+"\n"
+"    // TODO: Add split() to String.\n"
+"    // Split it into an array of strings.\n"
+"    var entries = []\n"
+"    var start = 0\n"
+"    var i = 0\n"
+"    var bytes = entryBuffer.bytes\n"
+"    while (i < bytes.count) {\n"
+"      if (bytes[i] == 0) {\n"
+"        var entry = entryBuffer[start...i]\n"
+"        start = i + 1\n"
+"        entries.add(entry)\n"
+"      }\n"
+"\n"
+"      i = i + 1\n"
+"    }\n"
+"\n"
+"    return entries\n"
+"  }\n"
+"\n"
+"  foreign static list_(path, fiber)\n"
+"}\n"
+"\n"
 "foreign class File {\n"
 "  static open(path) {\n"
 "    if (!(path is String)) Fiber.abort(\"Path must be a string.\")\n"
@@ -92,6 +124,7 @@ static const char* ioModuleSource =
 "      readStop_()\n"
 "\n"
 "      if (__line != null) {\n"
+"        // Emit the last line.\n"
 "        var line = __line\n"
 "        __line = null\n"
 "        if (__waitingFiber != null) __waitingFiber.transfer(line)\n"

test/io/directory/dir/a.txt

@@ -0,0 +1 @@
+this is a text file

test/io/directory/dir/b.txt

@@ -0,0 +1 @@
+this is a text file

test/io/directory/dir/c.txt

@@ -0,0 +1 @@
+this is a text file

test/io/directory/list.wren

@@ -0,0 +1,8 @@
+import "io" for Directory
+
+var entries = Directory.list("test/io/directory/dir")
+
+// Ignore OS-specific dot files like ".DS_Store".
+entries = entries.where {|entry| !entry.startsWith(".") }.toList
+
+System.print(entries) // expect: [a.txt, b.txt, c.txt]

test/io/directory/list_file.wren

@@ -0,0 +1,3 @@
+import "io" for Directory
+
+var entries = Directory.list("test/io/directory/dir/a.txt") // expect runtime error: not a directory

test/io/directory/list_nonexistent.wren

@@ -0,0 +1,3 @@
+import "io" for Directory
+
+Directory.list("nonexistent") // expect runtime error: no such file or directory

test/io/directory/list_wrong_arg_type.wren

@@ -0,0 +1,3 @@
+import "io" for Directory
+
+Directory.list(123) // expect runtime error: Path must be a string.