core: fix up pty Zig error sets

src/pty.zig

@@ -41,14 +41,16 @@ pub const Mode = packed struct {
 // a termio that doesn't use a pty. This isn't used in any user-facing
 // artifacts, this is just a stopgap to get compilation to work on iOS.
 const NullPty = struct {
-    pub const Errors = error{GetModeFailed};
+    pub const Error = OpenError || GetModeError || SetSizeError || ChildPreExecError;
 
     pub const Fd = posix.fd_t;
 
     master: Fd,
     slave: Fd,
 
-    pub fn open(size: winsize) error{}!Pty {
+    pub const OpenError = error{};
+
+    pub fn open(size: winsize) OpenError!Pty {
         _ = size;
         return .{ .master = 0, .slave = 0 };
     }
@@ -57,17 +59,23 @@ const NullPty = struct {
         _ = self;
     }
 
-    pub fn getMode(self: Pty) error{GetModeFailed}!Mode {
+    pub const GetModeError = error{GetModeFailed};
+
+    pub fn getMode(self: Pty) GetModeError!Mode {
         _ = self;
         return .{};
     }
 
-    pub fn setSize(self: *Pty, size: winsize) error{}!void {
+    pub const SetSizeError = error{};
+
+    pub fn setSize(self: *Pty, size: winsize) SetSizeError!void {
         _ = self;
         _ = size;
     }
 
-    pub fn childPreExec(self: Pty) error{}!void {
+    pub const ChildPreExecError = error{};
+
+    pub fn childPreExec(self: Pty) ChildPreExecError!void {
         _ = self;
     }
 };
@@ -76,14 +84,7 @@ const NullPty = struct {
 /// of Linux syscalls. The caller is responsible for detail-oriented handling
 /// of the returned file handles.
 const PosixPty = struct {
-    pub const Errors = error{
+    pub const Error = OpenError || GetModeError || GetSizeError || SetSizeError || ChildPreExecError;
-        GetModeFailed,
-        IoctlFailed,
-        OpenPtyFailed,
-        OperationNotSupported,
-        ProcessGroupFailed,
-        SetControllingTerminalFailed,
-    };
 
     pub const Fd = posix.fd_t;
 
@@ -111,10 +112,10 @@ const PosixPty = struct {
     master: Fd,
     slave: Fd,
 
+    pub const OpenError = error{OpenptyFailed};
+
     /// Open a new PTY with the given initial size.
-    pub fn open(size: winsize) error{
+    pub fn open(size: winsize) OpenError!Pty {
-        OpenptyFailed,
-    }!Pty {
         // Need to copy so that it becomes non-const.
         var sizeCopy = size;
 
@@ -171,7 +172,9 @@ const PosixPty = struct {
         self.* = undefined;
     }
 
-    pub fn getMode(self: Pty) error{GetModeFailed}!Mode {
+    pub const GetModeError = error{GetModeFailed};
+
+    pub fn getMode(self: Pty) GetModeError!Mode {
         var attrs: c.termios = undefined;
         if (c.tcgetattr(self.master, &attrs) != 0)
             return error.GetModeFailed;
@@ -182,8 +185,10 @@ const PosixPty = struct {
         };
     }
 
+    pub const GetSizeError = error{IoctlFailed};
+
     /// Return the size of the pty.
-    pub fn getSize(self: Pty) error{IoctlFailed}!winsize {
+    pub fn getSize(self: Pty) GetSizeError!winsize {
         var ws: winsize = undefined;
         if (c.ioctl(self.master, TIOCGWINSZ, @intFromPtr(&ws)) < 0)
             return error.IoctlFailed;
@@ -191,15 +196,19 @@ const PosixPty = struct {
         return ws;
     }
 
+    pub const SetSizeError = error{IoctlFailed};
+
     /// Set the size of the pty.
-    pub fn setSize(self: *Pty, size: winsize) error{IoctlFailed}!void {
+    pub fn setSize(self: *Pty, size: winsize) SetSizeError!void {
         if (c.ioctl(self.master, TIOCSWINSZ, @intFromPtr(&size)) < 0)
             return error.IoctlFailed;
     }
 
+    pub const ChildPreExecError = error{ OperationNotSupported, ProcessGroupFailed, SetControllingTerminalFailed };
+
     /// This should be called prior to exec in the forked child process
     /// in order to setup the tty properly.
-    pub fn childPreExec(self: Pty) error{ OperationNotSupported, ProcessGroupFailed, SetControllingTerminalFailed }!void {
+    pub fn childPreExec(self: Pty) ChildPreExecError!void {
         // Reset our signals
         var sa: posix.Sigaction = .{
             .handler = .{ .handler = posix.SIG.DFL },
@@ -240,10 +249,7 @@ const PosixPty = struct {
 
 /// Windows PTY creation and management.
 const WindowsPty = struct {
-    pub const Errors = error{
+    pub const Error = OpenError || GetSizeError || SetSizeError;
-        ResizeFailed,
-        Unexpected,
-    };
 
     pub const Fd = windows.HANDLE;
 
@@ -257,8 +263,10 @@ const WindowsPty = struct {
     pseudo_console: windows.exp.HPCON,
     size: winsize,
 
+    pub const OpenError = error{Unexpected};
+
     /// Open a new PTY with the given initial size.
-    pub fn open(size: winsize) error{Unexpected}!Pty {
+    pub fn open(size: winsize) OpenError!Pty {
         var pty: Pty = undefined;
 
         var pipe_path_buf: [128]u8 = undefined;
@@ -367,13 +375,17 @@ const WindowsPty = struct {
         self.* = undefined;
     }
 
+    pub const GetSizeError = error{};
+
     /// Return the size of the pty.
-    pub fn getSize(self: Pty) error{}!winsize {
+    pub fn getSize(self: Pty) GetSizeError!winsize {
         return self.size;
     }
 
+    pub const SetSizeError = error{ResizeFailed};
+
     /// Set the size of the pty.
-    pub fn setSize(self: *Pty, size: winsize) error{ResizeFailed}!void {
+    pub fn setSize(self: *Pty, size: winsize) SetSizeError!void {
         const result = windows.exp.kernel32.ResizePseudoConsole(
             self.pseudo_console,
             .{ .X = @intCast(size.ws_col), .Y = @intCast(size.ws_row) },