Remove commands for manually getting terminal size; no longer needed

Tea core now sends the terminal dimensions on start and when the window
is resized (except on Windows where SIGWINCH, the resize signal, is not
supported).

commands.go

@@ -1,23 +1,20 @@
 package tea
 
-// Convenience commands. Note part of the Bubble Tea runtime, but potentially
+// Convenience commands. Note part of the Bubble Tea core, but potentially
 // handy.
 
 import (
-	"os"
 	"time"
-
-	"golang.org/x/crypto/ssh/terminal"
 )
 
 // Every is a command that ticks in sync with the system clock. So, if you
 // wanted to tick with the system clock every second, minute or hour you
 // could use this. It's also handy for having different things tick in sync.
 //
-// Note that because we're ticking with the system clock the tick will likely
+// Because we're ticking with the system clock the tick will likely not run for
-// not run for the entire specified duration. For example, if we're ticking for
+// the entire specified duration. For example, if we're ticking for one minute
-// one minute and the clock is at 12:34:20 then the next tick will happen at
+// and the clock is at 12:34:20 then the next tick will happen at 12:35:00, 40
-// 12:35:00, 40 seconds later.
+// seconds later.
 func Every(duration time.Duration, fn func(time.Time) Msg) Cmd {
 	return func() Msg {
 		n := time.Now()
@@ -36,24 +33,3 @@ func Tick(d time.Duration, fn func(time.Time) Msg) Cmd {
 		return fn(<-t.C)
 	}
 }
-
-// TerminalSizeMsg defines an interface for a message that contains terminal
-// sizing as sent by GetTerminalSize.
-type TerminalSizeMsg interface {
-
-	// Size returns the terminal width and height, in that order
-	Size() (int, int)
-
-	// Error returns the error, if any, received when fetching the terminal size
-	Error() error
-}
-
-// GetTerminalSize is a command used to retrieve the terminal dimensions. Pass
-// a function used to construct your message, which would implement the
-// TerminalSizeMsg interaface.
-func GetTerminalSize(newMsgFunc func(int, int, error) TerminalSizeMsg) Cmd {
-	w, h, err := terminal.GetSize(int(os.Stdout.Fd()))
-	return func() Msg {
-		return newMsgFunc(w, h, err)
-	}
-}

commands_unix.go

@@ -1,23 +0,0 @@
-// +build darwin dragonfly freebsd linux netbsd openbsd solaris
-
-package tea
-
-import (
-	"os"
-	"os/signal"
-	"syscall"
-)
-
-// OnResize is used to listen for window resizes. Use GetTerminalSize to get
-// the windows dimensions. We don't fetch the window size with this command to
-// avoid a potential performance hit making the necessary system calls, since
-// this command could potentially run a lot. On that note, consider debouncing
-// this function.
-func OnResize(newMsgFunc func() Msg) Cmd {
-	return func() Msg {
-		sig := make(chan os.Signal, 1)
-		signal.Notify(sig, syscall.SIGWINCH)
-		<-sig
-		return newMsgFunc()
-	}
-}

commands_windows.go

@@ -1,9 +0,0 @@
-// +build windows
-
-package tea
-
-// OnResize is not supported on Windows at this time as Windows does not
-// support the SIGWINCH signal.
-func OnResize(newMsgFunc func() Msg) Cmd {
-	return nil
-}

tea.go

@@ -59,7 +59,7 @@ type quitMsg struct{}
 // can send a batchMsg with Batch.
 type batchMsg []Cmd
 
-// WindowSizeMsg is used to report on the terminal size. It's fired once
+// WindowSizeMsg is used to report on the terminal size. It's sent once
 // initially and then on every terminal resize.
 type WindowSizeMsg struct {
 	Width  int