lib/terminal: factor from cmd/progress, swap Azure/go-ansiterm for mattn/go-colorable

2019-09-26 21:14:47 +01:00 · 2019-09-26 21:14:47 +01:00 · 593de059be
commit 593de059be
parent c78d1dd18b
4 changed files with 120 additions and 106 deletions
--- a/lib/terminal/terminal.go
+++ b/lib/terminal/terminal.go
@ -0,0 +1,111 @@
+// Package terminal provides VT100 terminal codes and a windows
+// implementation of that.
+package terminal
+
+import (
+	"io"
+	"os"
+	"runtime"
+	"sync"
+
+	colorable "github.com/mattn/go-colorable"
+	"golang.org/x/crypto/ssh/terminal"
+)
+
+// VT100 codes
+const (
+	EraseLine         = "\x1b[2K"
+	MoveToStartOfLine = "\x1b[1G"
+	MoveUp            = "\x1b[1A"
+
+	Reset      = "\x1b[0m"
+	Bright     = "\x1b[1m"
+	Dim        = "\x1b[2m"
+	Underscore = "\x1b[4m"
+	Blink      = "\x1b[5m"
+	Reverse    = "\x1b[7m"
+	Hidden     = "\x1b[8m"
+
+	BlackFg   = "\x1b[30m"
+	RedFg     = "\x1b[31m"
+	GreenFg   = "\x1b[32m"
+	YellowFg  = "\x1b[33m"
+	BlueFg    = "\x1b[34m"
+	MagentaFg = "\x1b[35m"
+	CyanFg    = "\x1b[36m"
+	WhiteFg   = "\x1b[37m"
+
+	BlackBg   = "\x1b[40m"
+	RedBg     = "\x1b[41m"
+	GreenBg   = "\x1b[42m"
+	YellowBg  = "\x1b[43m"
+	BlueBg    = "\x1b[44m"
+	MagentaBg = "\x1b[45m"
+	CyanBg    = "\x1b[46m"
+	WhiteBg   = "\x1b[47m"
+
+	HiBlackFg   = "\x1b[90m"
+	HiRedFg     = "\x1b[91m"
+	HiGreenFg   = "\x1b[92m"
+	HiYellowFg  = "\x1b[93m"
+	HiBlueFg    = "\x1b[94m"
+	HiMagentaFg = "\x1b[95m"
+	HiCyanFg    = "\x1b[96m"
+	HiWhiteFg   = "\x1b[97m"
+
+	HiBlackBg   = "\x1b[100m"
+	HiRedBg     = "\x1b[101m"
+	HiGreenBg   = "\x1b[102m"
+	HiYellowBg  = "\x1b[103m"
+	HiBlueBg    = "\x1b[104m"
+	HiMagentaBg = "\x1b[105m"
+	HiCyanBg    = "\x1b[106m"
+	HiWhiteBg   = "\x1b[107m"
+)
+
+var (
+	// make sure that start is only called once
+	once sync.Once
+)
+
+// Start the terminal - must be called before use
+func Start() {
+	once.Do(func() {
+		f := os.Stdout
+		if !terminal.IsTerminal(int(f.Fd())) {
+			// If stdout not a tty then remove escape codes
+			Out = colorable.NewNonColorable(f)
+		} else if runtime.GOOS == "windows" && os.Getenv("TERM") != "" {
+			// If TERM is set just use stdout
+			Out = f
+		} else {
+			Out = colorable.NewColorable(f)
+		}
+	})
+}
+
+// WriteString writes the string passed in to the terminal
+func WriteString(s string) {
+	Write([]byte(s))
+}
+
+// GetSize reads the dimensions of the current terminal or returns a
+// sensible default
+func GetSize() (w, h int) {
+	w, h, err := terminal.GetSize(int(os.Stdout.Fd()))
+	if err != nil {
+		w, h = 80, 25
+	}
+	return w, h
+}
+
+// Out is an io.Writer which can be used to write to the terminal
+// eg for use with fmt.Fprintf(terminal.Out, "terminal fun: %d\n", n)
+var Out io.Writer
+
+// Write sends out to the VT100 terminal.
+// It will initialise the terminal if this is the first call.
+func Write(out []byte) {
+	Start()
+	_, _ = Out.Write(out)
+}