Implement Platform.homePath (#48)

* fix naming and path max

Co-authored-by: ruby0x1 <[email protected]>

Author: vladimyr

src/cli/modules.c

@@ -24,6 +24,7 @@ extern void fileRealPath(WrenVM* vm);
 extern void fileSize(WrenVM* vm);
 extern void fileStat(WrenVM* vm);
 extern void fileWriteBytes(WrenVM* vm);
+extern void platformHomePath(WrenVM* vm);
 extern void platformIsPosix(WrenVM* vm);
 extern void platformName(WrenVM* vm);
 extern void processAllArguments(WrenVM* vm);
@@ -169,6 +170,7 @@ static ModuleRegistry modules[] =
   END_MODULE
   MODULE(os)
     CLASS(Platform)
+      STATIC_METHOD("homePath", platformHomePath)
       STATIC_METHOD("isPosix", platformIsPosix)
       STATIC_METHOD("name", platformName)
     END_CLASS

src/module/os.c

@@ -15,6 +15,33 @@ void osSetArguments(int argc, const char* argv[])
   args = argv;
 }
 
+void platformHomePath(WrenVM* vm)
+{
+  wrenEnsureSlots(vm, 1);
+
+  char _buffer[WREN_PATH_MAX];
+  char* buffer = _buffer;
+  size_t length = sizeof(_buffer);
+  int result = uv_os_homedir(buffer, &length);
+
+  if (result == UV_ENOBUFS)
+  {
+    buffer = (char*)malloc(length);
+    result = uv_os_homedir(buffer, &length);
+  }
+
+  if (result != 0)
+  {
+    wrenSetSlotString(vm, 0, "Cannot get the current user's home directory.");
+    wrenAbortFiber(vm, 0);
+    return;
+  }
+
+  wrenSetSlotString(vm, 0, buffer);
+
+  if (buffer != _buffer) free(buffer);
+}
+
 void platformName(WrenVM* vm)
 {
   wrenEnsureSlots(vm, 1);

src/module/os.wren

@@ -1,4 +1,5 @@
 class Platform {
+  foreign static homePath
   foreign static isPosix
   foreign static name
 

src/module/os.wren.inc

@@ -3,6 +3,7 @@
 
 static const char* osModuleSource =
 "class Platform {\n"
+"  foreign static homePath\n"
 "  foreign static isPosix\n"
 "  foreign static name\n"
 "\n"

test/os/platform/homedir.wren

@@ -0,0 +1,7 @@
+import "io" for File, Directory
+import "os" for Platform
+
+System.print(Platform.homePath is String) // expect: true
+System.print(!Platform.homePath.isEmpty) // expect: true
+System.print(File.realPath(Platform.homePath) == Platform.homePath) // expect: true
+System.print(Directory.exists(Platform.homePath)) // expect: true