proposal to add windows support to the custom target functionality

codecov.yml

@@ -0,0 +1,8 @@
+coverage:
+  status:
+    project:
+      default:
+        informational: true
+    patch:
+      default:
+        informational: true

cursor.go

@@ -5,15 +5,14 @@ package cursor
 
 import (
 	"fmt"
-	"io"
 	"os"
 )
 
-var target io.Writer = os.Stdout
+var target Writer = os.Stdout
 
 // SetTarget allows for any arbitrary io.Writer to be used
 // for cursor movement (will not work on Windows).
-func SetTarget(w io.Writer) {
+func SetTarget(w Writer) {
 	target = w
 }
 

cursor_test.go

@@ -1,9 +1,7 @@
 package cursor
 
 import (
-	"bytes"
 	"fmt"
-	"runtime"
 	"testing"
 )
 
@@ -27,75 +25,3 @@ func TestHeightCannotBeNegative(t *testing.T) {
 		t.Errorf("height is negative: %d", height)
 	}
 }
-
-func TestCustomIOWriter(t *testing.T) {
-	if runtime.GOOS == "windows" {
-		t.Skip("skipping these tests on windows")
-	}
-
-	var w bytes.Buffer
-	SetTarget(&w)
-
-	Up(2)
-	expected := "\x1b[2A"
-	actual := w.String()
-	if expected != actual {
-		t.Errorf("wanted: %v, got %v", expected, actual)
-	}
-
-	w.Reset()
-	Down(2)
-	expected = "\x1b[2B"
-	actual = w.String()
-	if expected != actual {
-		t.Errorf("wanted: %v, got %v", expected, actual)
-	}
-
-	w.Reset()
-	Right(2)
-	expected = "\x1b[2C"
-	actual = w.String()
-	if expected != actual {
-		t.Errorf("wanted: %v, got %v", expected, actual)
-	}
-
-	w.Reset()
-	Left(2)
-	expected = "\x1b[2D"
-	actual = w.String()
-	if expected != actual {
-		t.Errorf("wanted: %v, got %v", expected, actual)
-	}
-
-	w.Reset()
-	Hide()
-	expected = "\x1b[?25l"
-	actual = w.String()
-	if expected != actual {
-		t.Errorf("wanted: %v, got %v", expected, actual)
-	}
-
-	w.Reset()
-	Show()
-	expected = "\x1b[?25h"
-	actual = w.String()
-	if expected != actual {
-		t.Errorf("wanted: %v, got %v", expected, actual)
-	}
-
-	w.Reset()
-	ClearLine()
-	expected = "\x1b[2K"
-	actual = w.String()
-	if expected != actual {
-		t.Errorf("wanted: %v, got %v", expected, actual)
-	}
-
-	w.Reset()
-	HorizontalAbsolute(3)
-	expected = "\x1b[4G"
-	actual = w.String()
-	if expected != actual {
-		t.Errorf("wanted: %v, got %v", expected, actual)
-	}
-}

cursor_test_linux.go

@@ -0,0 +1,109 @@
+package cursor
+
+import (
+	"log"
+	"os"
+	"testing"
+)
+
+func TestCustomIOWriter(t *testing.T) {
+	tmpFile, err := os.CreateTemp("", "testingTmpFile-")
+	if err != nil {
+		log.Fatal(err)
+	}
+	defer os.Remove(tmpFile.Name())
+
+	w := tmpFile
+	SetTarget(w)
+
+	Up(2)
+	expected := "\x1b[2A"
+	actual := getFileContent(t, w.Name())
+	if expected != actual {
+		t.Errorf("wanted: %v, got %v", expected, actual)
+	}
+
+	clearFile(t, w)
+	Down(2)
+	expected = "\x1b[2B"
+	actual = getFileContent(t, w.Name())
+	if expected != actual {
+		t.Errorf("wanted: %v, got %v", expected, actual)
+	}
+
+	clearFile(t, w)
+	Right(2)
+	expected = "\x1b[2C"
+	actual = getFileContent(t, w.Name())
+	if expected != actual {
+		t.Errorf("wanted: %v, got %v", expected, actual)
+	}
+
+	clearFile(t, w)
+	Left(2)
+	expected = "\x1b[2D"
+	actual = getFileContent(t, w.Name())
+	if expected != actual {
+		t.Errorf("wanted: %v, got %v", expected, actual)
+	}
+
+	clearFile(t, w)
+	Hide()
+	expected = "\x1b[?25l"
+	actual = getFileContent(t, w.Name())
+	if expected != actual {
+		t.Errorf("wanted: %v, got %v", expected, actual)
+	}
+
+	clearFile(t, w)
+	Show()
+	expected = "\x1b[?25h"
+	actual = getFileContent(t, w.Name())
+	if expected != actual {
+		t.Errorf("wanted: %v, got %v", expected, actual)
+	}
+
+	clearFile(t, w)
+	ClearLine()
+	expected = "\x1b[2K"
+	actual = getFileContent(t, w.Name())
+	if expected != actual {
+		t.Errorf("wanted: %v, got %v", expected, actual)
+	}
+
+	clearFile(t, w)
+	HorizontalAbsolute(3)
+	expected = "\x1b[4G"
+	actual = getFileContent(t, w.Name())
+	if expected != actual {
+		t.Errorf("wanted: %v, got %v", expected, actual)
+	}
+}
+
+func getFileContent(t *testing.T, fileName string) string {
+	t.Helper()
+	content, err := os.ReadFile(fileName)
+	if err != nil {
+		t.Errorf("failed to read file contents: %s", err)
+
+		return ""
+	}
+
+	return string(content)
+}
+
+func clearFile(t *testing.T, file *os.File) {
+	t.Helper()
+	err := file.Truncate(0)
+	if err != nil {
+		t.Errorf("failed to clear file")
+
+		return
+	}
+	_, err = file.Seek(0, 0)
+	if err != nil {
+		t.Errorf("failed to clear file")
+
+		return
+	}
+}

cursor_windows.go

@@ -1,15 +1,16 @@
 package cursor
 
 import (
-	"io"
 	"os"
 	"syscall"
 	"unsafe"
 )
 
-// SetTarget allows for any arbitrary io.Writer to be used
-// for cursor movement (will not work on Windows).
-func SetTarget(w io.Writer) {
+var target Writer = os.Stdout
+
+// SetTarget allows for any arbitrary Writer to be used
+func SetTarget(w Writer) {
+	target = w
 }
 
 // Up moves the cursor n lines up relative to the current position.
@@ -39,7 +40,7 @@ func Left(n int) {
 }
 
 func move(x int, y int) {
-	handle := syscall.Handle(os.Stdout.Fd())
+	handle := syscall.Handle(target.Fd())
 
 	var csbi consoleScreenBufferInfo
 	_, _, _ = procGetConsoleScreenBufferInfo.Call(uintptr(handle), uintptr(unsafe.Pointer(&csbi)))
@@ -54,7 +55,7 @@ func move(x int, y int) {
 // HorizontalAbsolute moves the cursor to n horizontally.
 // The position n is absolute to the start of the line.
 func HorizontalAbsolute(n int) {
-	handle := syscall.Handle(os.Stdout.Fd())
+	handle := syscall.Handle(target.Fd())
 
 	var csbi consoleScreenBufferInfo
 	_, _, _ = procGetConsoleScreenBufferInfo.Call(uintptr(handle), uintptr(unsafe.Pointer(&csbi)))
@@ -74,7 +75,7 @@ func HorizontalAbsolute(n int) {
 // Don't forget to show the cursor at least at the end of your application.
 // Otherwise the user might have a terminal with a permanently hidden cursor, until he reopens the terminal.
 func Show() {
-	handle := syscall.Handle(os.Stdout.Fd())
+	handle := syscall.Handle(target.Fd())
 
 	var cci consoleCursorInfo
 	_, _, _ = procGetConsoleCursorInfo.Call(uintptr(handle), uintptr(unsafe.Pointer(&cci)))
@@ -87,7 +88,7 @@ func Show() {
 // Don't forget to show the cursor at least at the end of your application with Show.
 // Otherwise the user might have a terminal with a permanently hidden cursor, until he reopens the terminal.
 func Hide() {
-	handle := syscall.Handle(os.Stdout.Fd())
+	handle := syscall.Handle(target.Fd())
 
 	var cci consoleCursorInfo
 	_, _, _ = procGetConsoleCursorInfo.Call(uintptr(handle), uintptr(unsafe.Pointer(&cci)))
@@ -98,7 +99,7 @@ func Hide() {
 
 // ClearLine clears the current line and moves the cursor to it's start position.
 func ClearLine() {
-	handle := syscall.Handle(os.Stdout.Fd())
+	handle := syscall.Handle(target.Fd())
 
 	var csbi consoleScreenBufferInfo
 	_, _, _ = procGetConsoleScreenBufferInfo.Call(uintptr(handle), uintptr(unsafe.Pointer(&csbi)))

utils.go

@@ -1,5 +1,7 @@
 package cursor
 
+import "io"
+
 var height int
 
 // Bottom moves the cursor to the bottom of the terminal.
@@ -71,3 +73,8 @@ func ClearLinesDown(n int) {
 		DownAndClear(1)
 	}
 }
+
+type Writer interface {
+	io.Writer
+	Fd() uintptr
+}