From bc68e99fbce5ae8aad4806768b6f06ea0c743731 Mon Sep 17 00:00:00 2001
From: "Guillaume J. Charmes" <git+guillaume@charmes.net>
Date: Tue, 31 Oct 2023 09:07:26 -0400
Subject: [PATCH 1/5] Minor cosmetic cleanups in the tests. Add missing error
 checks. Use Fatal instead of Error to avoid panics upon failure.

---
 doc_test.go | 193 +++++++++++++++++++++++-----------------------------
 io_test.go  |  55 ++++++++-------
 2 files changed, 116 insertions(+), 132 deletions(-)

diff --git a/doc_test.go b/doc_test.go
index a1d915a..3e6a3fa 100644
--- a/doc_test.go
+++ b/doc_test.go
@@ -7,17 +7,10 @@ import (
 	"testing"
 )
 
-// Will fill p from reader r
+// Will fill p from reader r.
 func readBytes(r io.Reader, p []byte) error {
-	bytesRead := 0
-	for bytesRead < len(p) {
-		n, err := r.Read(p[bytesRead:])
-		if err != nil {
-			return err
-		}
-		bytesRead = bytesRead + n
-	}
-	return nil
+	_, err := io.ReadFull(r, p)
+	return err
 }
 
 func TestOpen(t *testing.T) {
@@ -25,17 +18,15 @@ func TestOpen(t *testing.T) {
 
 	pty, tty, err := Open()
 	if err != nil {
-		t.Errorf("Unexpected error from Open: %s", err)
+		t.Fatalf("Unexpected error from Open: %s.", err)
 	}
 
-	err = tty.Close()
-	if err != nil {
-		t.Errorf("Unexpected error from tty Close: %s", err)
+	if err := tty.Close(); err != nil {
+		t.Errorf("Unexpected error from tty Close: %s.", err)
 	}
 
-	err = pty.Close()
-	if err != nil {
-		t.Errorf("Unexpected error from pty Close: %s", err)
+	if err := pty.Close(); err != nil {
+		t.Errorf("Unexpected error from pty Close: %s.", err)
 	}
 }
 
@@ -44,24 +35,22 @@ func TestName(t *testing.T) {
 
 	pty, tty, err := Open()
 	if err != nil {
-		t.Errorf("Unexpected error from Open: %s", err)
+		t.Fatalf("Unexpected error from Open: %s.", err)
 	}
 
 	// Check name isn't empty. There's variation on what exactly the OS calls these files.
 	if pty.Name() == "" {
-		t.Error("pty name was empty")
+		t.Error("Pty name was empty.")
 	}
 	if tty.Name() == "" {
-		t.Error("tty name was empty")
+		t.Error("Tty name was empty.")
 	}
 
-	err = tty.Close()
-	if err != nil {
+	if err := tty.Close(); err != nil {
 		t.Errorf("Unexpected error from tty Close: %s", err)
 	}
 
-	err = pty.Close()
-	if err != nil {
+	if err := pty.Close(); err != nil {
 		t.Errorf("Unexpected error from pty Close: %s", err)
 	}
 }
@@ -74,30 +63,30 @@ func TestOpenByName(t *testing.T) {
 
 	pty, tty, err := Open()
 	if err != nil {
-		t.Fatal(err)
+		t.Fatalf("Error: open: %s.", err)
 	}
-	defer pty.Close()
-	defer tty.Close()
+	defer func() { _ = pty.Close() }()
+	defer func() { _ = tty.Close() }()
 
-	ttyFile, err := os.OpenFile(tty.Name(), os.O_RDWR, 0600)
+	ttyFile, err := os.OpenFile(tty.Name(), os.O_RDWR, 0o600)
 	if err != nil {
-		t.Fatalf("Failed to open tty file: %v", err)
+		t.Fatalf("Failed to open tty file: %s.", err)
 	}
-	defer ttyFile.Close()
+	defer func() { _ = ttyFile.Close() }()
 
 	// Ensure we can write to the newly opened tty file and read on the pty.
 	text := []byte("ping")
 	n, err := ttyFile.Write(text)
 	if err != nil {
-		t.Errorf("Unexpected error from Write: %s", err)
+		t.Fatalf("Unexpected error from Write: %s.", err)
 	}
 	if n != len(text) {
-		t.Errorf("Unexpected count returned from Write, got %d expected %d", n, len(text))
+		t.Errorf("Unexpected count returned from Write, got %d expected %d.", n, len(text))
 	}
 
 	buffer := make([]byte, len(text))
 	if err := readBytes(pty, buffer); err != nil {
-		t.Errorf("Unexpected error from readBytes: %s", err)
+		t.Fatalf("Unexpected error from readBytes: %s.", err)
 	}
 	if !bytes.Equal(text, buffer) {
 		t.Errorf("Unexpected result returned from Read, got %v expected %v", buffer, text)
@@ -109,34 +98,32 @@ func TestGetsize(t *testing.T) {
 
 	pty, tty, err := Open()
 	if err != nil {
-		t.Errorf("Unexpected error from Open: %s", err)
+		t.Fatalf("Unexpected error from Open: %s.", err)
 	}
 
 	prows, pcols, err := Getsize(pty)
 	if err != nil {
-		t.Errorf("Unexpected error from Getsize: %s", err)
+		t.Errorf("Unexpected error from Getsize: %s.", err)
 	}
 
 	trows, tcols, err := Getsize(tty)
 	if err != nil {
-		t.Errorf("Unexpected error from Getsize: %s", err)
+		t.Errorf("Unexpected error from Getsize: %s.", err)
 	}
 
 	if prows != trows {
-		t.Errorf("pty rows != tty rows: %d != %d", prows, trows)
+		t.Errorf("pty rows != tty rows: %d != %d.", prows, trows)
 	}
 	if prows != trows {
-		t.Errorf("pty cols != tty cols: %d != %d", pcols, tcols)
+		t.Errorf("pty cols != tty cols: %d != %d.", pcols, tcols)
 	}
 
-	err = tty.Close()
-	if err != nil {
-		t.Errorf("Unexpected error from tty Close: %s", err)
+	if err := tty.Close(); err != nil {
+		t.Errorf("Unexpected error from tty Close: %s.", err)
 	}
 
-	err = pty.Close()
-	if err != nil {
-		t.Errorf("Unexpected error from pty Close: %s", err)
+	if err := pty.Close(); err != nil {
+		t.Errorf("Unexpected error from pty Close: %s.", err)
 	}
 }
 
@@ -145,40 +132,38 @@ func TestGetsizefull(t *testing.T) {
 
 	pty, tty, err := Open()
 	if err != nil {
-		t.Errorf("Unexpected error from Open: %s", err)
+		t.Fatalf("Unexpected error from Open: %s.", err)
 	}
 
 	psize, err := GetsizeFull(pty)
 	if err != nil {
-		t.Errorf("Unexpected error from GetsizeFull: %s", err)
+		t.Fatalf("Unexpected error from GetsizeFull: %s.", err)
 	}
 
 	tsize, err := GetsizeFull(tty)
 	if err != nil {
-		t.Errorf("Unexpected error from GetsizeFull: %s", err)
+		t.Fatalf("Unexpected error from GetsizeFull: %s.", err)
 	}
 
 	if psize.X != tsize.X {
-		t.Errorf("pty x != tty x: %d != %d", psize.X, tsize.X)
+		t.Errorf("pty x != tty x: %d != %d.", psize.X, tsize.X)
 	}
 	if psize.Y != tsize.Y {
-		t.Errorf("pty y != tty y: %d != %d", psize.Y, tsize.Y)
+		t.Errorf("pty y != tty y: %d != %d.", psize.Y, tsize.Y)
 	}
 	if psize.Rows != tsize.Rows {
-		t.Errorf("pty rows != tty rows: %d != %d", psize.Rows, tsize.Rows)
+		t.Errorf("pty rows != tty rows: %d != %d.", psize.Rows, tsize.Rows)
 	}
 	if psize.Cols != tsize.Cols {
-		t.Errorf("pty cols != tty cols: %d != %d", psize.Cols, tsize.Cols)
+		t.Errorf("pty cols != tty cols: %d != %d.", psize.Cols, tsize.Cols)
 	}
 
-	err = tty.Close()
-	if err != nil {
-		t.Errorf("Unexpected error from tty Close: %s", err)
+	if err := tty.Close(); err != nil {
+		t.Errorf("Unexpected error from tty Close: %s.", err)
 	}
 
-	err = pty.Close()
-	if err != nil {
-		t.Errorf("Unexpected error from pty Close: %s", err)
+	if err := pty.Close(); err != nil {
+		t.Errorf("Unexpected error from pty Close: %s.", err)
 	}
 }
 
@@ -187,12 +172,12 @@ func TestSetsize(t *testing.T) {
 
 	pty, tty, err := Open()
 	if err != nil {
-		t.Errorf("Unexpected error from Open: %s", err)
+		t.Fatalf("Unexpected error from Open: %s.", err)
 	}
 
 	psize, err := GetsizeFull(pty)
 	if err != nil {
-		t.Errorf("Unexpected error from GetsizeFull: %s", err)
+		t.Fatalf("Unexpected error from GetsizeFull: %s.", err)
 	}
 
 	psize.X = psize.X + 1
@@ -200,37 +185,34 @@ func TestSetsize(t *testing.T) {
 	psize.Rows = psize.Rows + 1
 	psize.Cols = psize.Cols + 1
 
-	err = Setsize(tty, psize)
-	if err != nil {
-		t.Errorf("Unexpected error from Setsize: %s", err)
+	if err := Setsize(tty, psize); err != nil {
+		t.Fatalf("Unexpected error from Setsize: %s", err)
 	}
 
 	tsize, err := GetsizeFull(tty)
 	if err != nil {
-		t.Errorf("Unexpected error from GetsizeFull: %s", err)
+		t.Fatalf("Unexpected error from GetsizeFull: %s.", err)
 	}
 
 	if psize.X != tsize.X {
-		t.Errorf("pty x != tty x: %d != %d", psize.X, tsize.X)
+		t.Errorf("pty x != tty x: %d != %d.", psize.X, tsize.X)
 	}
 	if psize.Y != tsize.Y {
-		t.Errorf("pty y != tty y: %d != %d", psize.Y, tsize.Y)
+		t.Errorf("pty y != tty y: %d != %d.", psize.Y, tsize.Y)
 	}
 	if psize.Rows != tsize.Rows {
-		t.Errorf("pty rows != tty rows: %d != %d", psize.Rows, tsize.Rows)
+		t.Errorf("pty rows != tty rows: %d != %d.", psize.Rows, tsize.Rows)
 	}
 	if psize.Cols != tsize.Cols {
-		t.Errorf("pty cols != tty cols: %d != %d", psize.Cols, tsize.Cols)
+		t.Errorf("pty cols != tty cols: %d != %d.", psize.Cols, tsize.Cols)
 	}
 
-	err = tty.Close()
-	if err != nil {
-		t.Errorf("Unexpected error from tty Close: %s", err)
+	if err := tty.Close(); err != nil {
+		t.Errorf("Unexpected error from tty Close: %s.", err)
 	}
 
-	err = pty.Close()
-	if err != nil {
-		t.Errorf("Unexpected error from pty Close: %s", err)
+	if err := pty.Close(); err != nil {
+		t.Errorf("Unexpected error from pty Close: %s.", err)
 	}
 }
 
@@ -239,7 +221,7 @@ func TestReadWriteText(t *testing.T) {
 
 	pty, tty, err := Open()
 	if err != nil {
-		t.Errorf("Unexpected error from Open: %s", err)
+		t.Fatalf("Unexpected error from Open: %s.", err)
 	}
 
 	// Write to tty, read from pty
@@ -249,16 +231,15 @@ func TestReadWriteText(t *testing.T) {
 		t.Errorf("Unexpected error from Write: %s", err)
 	}
 	if n != len(text) {
-		t.Errorf("Unexpected count returned from Write, got %d expected %d", n, len(text))
+		t.Errorf("Unexpected count returned from Write, got %d expected %d.", n, len(text))
 	}
 
 	buffer := make([]byte, 4)
-	err = readBytes(pty, buffer)
-	if err != nil {
-		t.Errorf("Unexpected error from readBytes: %s", err)
+	if err := readBytes(pty, buffer); err != nil {
+		t.Fatalf("Unexpected error from readBytes: %s.", err)
 	}
 	if !bytes.Equal(text, buffer) {
-		t.Errorf("Unexpected result returned from Read, got %v expected %v", buffer, text)
+		t.Errorf("Unexpected result returned from Read, got %v expected %v.", buffer, text)
 	}
 
 	// Write to pty, read from tty.
@@ -266,41 +247,41 @@ func TestReadWriteText(t *testing.T) {
 	text = []byte("pong\n")
 	n, err = pty.Write(text)
 	if err != nil {
-		t.Errorf("Unexpected error from Write: %s", err)
+		t.Fatalf("Unexpected error from Write: %s.", err)
 	}
 	if n != len(text) {
-		t.Errorf("Unexpected count returned from Write, got %d expected %d", n, len(text))
+		t.Errorf("Unexpected count returned from Write, got %d expected %d.", n, len(text))
 	}
 
 	buffer = make([]byte, 5)
 	err = readBytes(tty, buffer)
 	if err != nil {
-		t.Errorf("Unexpected error from readBytes: %s", err)
+		t.Errorf("Unexpected error from readBytes: %s.", err)
 	}
 	expect := []byte("pong\n")
 	if !bytes.Equal(expect, buffer) {
-		t.Errorf("Unexpected result returned from Read, got %v expected %v", buffer, expect)
+		t.Errorf("Unexpected result returned from Read, got %v expected %v.", buffer, expect)
 	}
 
 	// Read the echo back from pty
 	buffer = make([]byte, 5)
 	err = readBytes(pty, buffer)
 	if err != nil {
-		t.Errorf("Unexpected error from readBytes: %s", err)
+		t.Fatalf("Unexpected error from readBytes: %s.", err)
 	}
 	expect = []byte("pong\r")
 	if !bytes.Equal(expect, buffer) {
-		t.Errorf("Unexpected result returned from Read, got %v expected %v", buffer, expect)
+		t.Errorf("Unexpected result returned from Read, got %v expected %v.", buffer, expect)
 	}
 
 	err = tty.Close()
 	if err != nil {
-		t.Errorf("Unexpected error from tty Close: %s", err)
+		t.Errorf("Unexpected error from tty Close: %s.", err)
 	}
 
 	err = pty.Close()
 	if err != nil {
-		t.Errorf("Unexpected error from pty Close: %s", err)
+		t.Errorf("Unexpected error from pty Close: %s.", err)
 	}
 }
 
@@ -309,66 +290,64 @@ func TestReadWriteControls(t *testing.T) {
 
 	pty, tty, err := Open()
 	if err != nil {
-		t.Errorf("Unexpected error from Open: %s", err)
+		t.Fatalf("Unexpected error from Open: %s.", err)
 	}
 
-	// Write the start of a line to pty
+	// Write the start of a line to pty.
 	text := []byte("pind")
 	n, err := pty.Write(text)
 	if err != nil {
-		t.Errorf("Unexpected error from Write: %s", err)
+		t.Fatalf("Unexpected error from Write: %s.", err)
 	}
 	if n != len(text) {
-		t.Errorf("Unexpected count returned from Write, got %d expected %d", n, len(text))
+		t.Errorf("Unexpected count returned from Write, got %d expected %d.", n, len(text))
 	}
 
-	// Backspace that last char
+	// Backspace that last char.
 	n, err = pty.Write([]byte("\b"))
 	if err != nil {
-		t.Errorf("Unexpected error from Write: %s", err)
+		t.Fatalf("Unexpected error from Write: %s.", err)
 	}
 	if n != 1 {
-		t.Errorf("Unexpected count returned from Write, got %d expected %d", n, 1)
+		t.Errorf("Unexpected count returned from Write, got %d expected %d.", n, 1)
 	}
 
-	// Write the correct char and a CR
+	// Write the correct char and a CR.
 	n, err = pty.Write([]byte("g\n"))
 	if err != nil {
-		t.Errorf("Unexpected error from Write: %s", err)
+		t.Fatalf("Unexpected error from Write: %s.", err)
 	}
 	if n != 2 {
-		t.Errorf("Unexpected count returned from Write, got %d expected %d", n, 2)
+		t.Errorf("Unexpected count returned from Write, got %d expected %d.", n, 2)
 	}
 
 	// Read the line
 	buffer := make([]byte, 7)
 	err = readBytes(tty, buffer)
 	if err != nil {
-		t.Errorf("Unexpected error from readBytes: %s", err)
+		t.Errorf("Unexpected error from readBytes: %s.", err)
 	}
 	expect := []byte("pind\bg\n")
 	if !bytes.Equal(expect, buffer) {
-		t.Errorf("Unexpected result returned from Read, got %v expected %v", buffer, expect)
+		t.Errorf("Unexpected result returned from Read, got %v expected %v.", buffer, expect)
 	}
 
 	// Read the echo back from pty
 	buffer = make([]byte, 7)
 	err = readBytes(pty, buffer)
 	if err != nil {
-		t.Errorf("Unexpected error from readBytes: %s", err)
+		t.Errorf("Unexpected error from readBytes: %s.", err)
 	}
 	expect = []byte("pind^Hg")
 	if !bytes.Equal(expect, buffer) {
-		t.Errorf("Unexpected result returned from Read, got %v expected %v", buffer, expect)
+		t.Errorf("Unexpected result returned from Read, got %v expected %v.", buffer, expect)
 	}
 
-	err = tty.Close()
-	if err != nil {
-		t.Errorf("Unexpected error from tty Close: %s", err)
+	if err := tty.Close(); err != nil {
+		t.Errorf("Unexpected error from tty Close: %s.", err)
 	}
 
-	err = pty.Close()
-	if err != nil {
-		t.Errorf("Unexpected error from pty Close: %s", err)
+	if err := pty.Close(); err != nil {
+		t.Errorf("Unexpected error from pty Close: %s.", err)
 	}
 }
diff --git a/io_test.go b/io_test.go
index 0837d9e..661559e 100644
--- a/io_test.go
+++ b/io_test.go
@@ -4,13 +4,12 @@
 package pty
 
 import (
-	"testing"
-
 	"context"
 	"errors"
 	"os"
 	"runtime"
 	"sync"
+	"testing"
 	"time"
 )
 
@@ -19,7 +18,7 @@ const (
 	timeout        = time.Second
 )
 
-var mu sync.Mutex
+var glTestFdLock sync.Mutex
 
 // Check that SetDeadline() works for ptmx.
 // Outstanding Read() calls must be interrupted by deadline.
@@ -28,25 +27,27 @@ var mu sync.Mutex
 func TestReadDeadline(t *testing.T) {
 	ptmx, success := prepare(t)
 
-	err := ptmx.SetDeadline(time.Now().Add(timeout / 10))
-	if err != nil {
+	if err := ptmx.SetDeadline(time.Now().Add(timeout / 10)); err != nil {
 		if errors.Is(err, os.ErrNoDeadline) {
-			t.Skipf("deadline is not supported on %s/%s", runtime.GOOS, runtime.GOARCH)
+			t.Skipf("Deadline is not supported on %s/%s.", runtime.GOOS, runtime.GOARCH)
 		} else {
-			t.Fatalf("error: set deadline: %v\n", err)
+			t.Fatalf("Error: set deadline: %s.", err)
 		}
 	}
 
-	var buf = make([]byte, 1)
+	buf := make([]byte, 1)
 	n, err := ptmx.Read(buf)
 	success()
+	if err != nil && !errors.Is(err, os.ErrDeadlineExceeded) {
+		t.Fatalf("Unexpected read error: %s.", err)
+	}
 
 	if n != 0 && buf[0] != errMarker {
-		t.Errorf("received unexpected data from pmtx (%d bytes): 0x%X; err=%v", n, buf, err)
+		t.Errorf("Received unexpected data from pmtx (%d bytes): 0x%X; err=%v.", n, buf, err)
 	}
 }
 
-// Check that ptmx.Close() interrupts outstanding ptmx.Read() calls
+// Check that ptmx.Close() interrupts outstanding ptmx.Read() calls.
 //
 // https://github.com/creack/pty/issues/114
 // https://github.com/creack/pty/issues/88
@@ -55,23 +56,27 @@ func TestReadClose(t *testing.T) {
 
 	go func() {
 		time.Sleep(timeout / 10)
-		err := ptmx.Close()
-		if err != nil {
-			t.Errorf("failed to close ptmx: %v", err)
+		if err := ptmx.Close(); err != nil {
+			t.Errorf("Failed to close ptmx: %s.", err)
 		}
 	}()
 
-	var buf = make([]byte, 1)
+	buf := make([]byte, 1)
 	n, err := ptmx.Read(buf)
 	success()
+	if err != nil && !errors.Is(err, os.ErrClosed) {
+		t.Fatalf("Unexpected read error: %s.", err)
+	}
 
 	if n != 0 && buf[0] != errMarker {
-		t.Errorf("received unexpected data from pmtx (%d bytes): 0x%X; err=%v", n, buf, err)
+		t.Errorf("Received unexpected data from pmtx (%d bytes): 0x%X; err=%v.", n, buf, err)
 	}
 }
 
 // Open pty and setup watchdogs for graceful and not so graceful failure modes
 func prepare(t *testing.T) (ptmx *os.File, done func()) {
+	t.Helper()
+
 	if runtime.GOOS == "darwin" {
 		t.Log("creack/pty uses blocking i/o on darwin intentionally:")
 		t.Log("> https://github.com/creack/pty/issues/52")
@@ -81,13 +86,13 @@ func prepare(t *testing.T) (ptmx *os.File, done func()) {
 	}
 
 	// Due to data race potential in (*os.File).Fd()
-	// we should never run these two tests in parallel
-	mu.Lock()
-	t.Cleanup(mu.Unlock)
+	// we should never run these two tests in parallel.
+	glTestFdLock.Lock()
+	t.Cleanup(glTestFdLock.Unlock)
 
 	ptmx, pts, err := Open()
 	if err != nil {
-		t.Fatalf("error: open: %v\n", err)
+		t.Fatalf("Error: open: %s.\n", err)
 	}
 	t.Cleanup(func() { _ = ptmx.Close() })
 	t.Cleanup(func() { _ = pts.Close() })
@@ -99,21 +104,21 @@ func prepare(t *testing.T) (ptmx *os.File, done func()) {
 		case <-ctx.Done():
 			// ptmx.Read() did not block forever, yay!
 		case <-time.After(timeout):
-			_, err := pts.Write([]byte{errMarker}) // unblock ptmx.Read()
-			if err != nil {
-				t.Errorf("failed to write to pts: %v", err)
+			if _, err := pts.Write([]byte{errMarker}); err != nil { // unblock ptmx.Read()
+				t.Errorf("Failed to write to pts: %s.", err)
 			}
-			t.Error("ptmx.Read() was not unblocked")
+			t.Error("ptmx.Read() was not unblocked.")
 			done() // cancel panic()
 		}
 	}()
 	go func() {
 		select {
 		case <-ctx.Done():
-			// Test has either failed or succeeded; it definitely did not hang
+			// Test has either failed or succeeded; it definitely did not hang.
 		case <-time.After(timeout * 10 / 9): // timeout +11%
-			panic("ptmx.Read() was not unblocked; avoid hanging forever") // just in case
+			panic("ptmx.Read() was not unblocked; avoid hanging forever.") // Just in case.
 		}
 	}()
+
 	return ptmx, done
 }

From ccf8e7e6b689fcf5142a9a1b39f2a5b173fba9e0 Mon Sep 17 00:00:00 2001
From: "Guillaume J. Charmes" <git+guillaume@charmes.net>
Date: Tue, 31 Oct 2023 09:20:53 -0400
Subject: [PATCH 2/5] Add openClose helper in tests to remove duplication.

---
 doc_test.go | 117 ++++++++++++----------------------------------------
 1 file changed, 27 insertions(+), 90 deletions(-)

diff --git a/doc_test.go b/doc_test.go
index 3e6a3fa..6e5916e 100644
--- a/doc_test.go
+++ b/doc_test.go
@@ -13,30 +13,37 @@ func readBytes(r io.Reader, p []byte) error {
 	return err
 }
 
-func TestOpen(t *testing.T) {
-	t.Parallel()
+// openCloses opens a pty/tty pair and stages the closing as part of the cleanup.
+func openClose(t *testing.T) (pty, tty *os.File) {
+	t.Helper()
 
 	pty, tty, err := Open()
 	if err != nil {
 		t.Fatalf("Unexpected error from Open: %s.", err)
 	}
+	t.Cleanup(func() {
+		if err := tty.Close(); err != nil {
+			t.Errorf("Unexpected error from tty Close: %s.", err)
+		}
 
-	if err := tty.Close(); err != nil {
-		t.Errorf("Unexpected error from tty Close: %s.", err)
-	}
+		if err := pty.Close(); err != nil {
+			t.Errorf("Unexpected error from pty Close: %s.", err)
+		}
+	})
 
-	if err := pty.Close(); err != nil {
-		t.Errorf("Unexpected error from pty Close: %s.", err)
-	}
+	return pty, tty
+}
+
+func TestOpen(t *testing.T) {
+	t.Parallel()
+
+	openClose(t)
 }
 
 func TestName(t *testing.T) {
 	t.Parallel()
 
-	pty, tty, err := Open()
-	if err != nil {
-		t.Fatalf("Unexpected error from Open: %s.", err)
-	}
+	pty, tty := openClose(t)
 
 	// Check name isn't empty. There's variation on what exactly the OS calls these files.
 	if pty.Name() == "" {
@@ -45,14 +52,6 @@ func TestName(t *testing.T) {
 	if tty.Name() == "" {
 		t.Error("Tty name was empty.")
 	}
-
-	if err := tty.Close(); err != nil {
-		t.Errorf("Unexpected error from tty Close: %s", err)
-	}
-
-	if err := pty.Close(); err != nil {
-		t.Errorf("Unexpected error from pty Close: %s", err)
-	}
 }
 
 // TestOpenByName ensures that the name associated with the tty is valid
@@ -61,12 +60,7 @@ func TestName(t *testing.T) {
 func TestOpenByName(t *testing.T) {
 	t.Parallel()
 
-	pty, tty, err := Open()
-	if err != nil {
-		t.Fatalf("Error: open: %s.", err)
-	}
-	defer func() { _ = pty.Close() }()
-	defer func() { _ = tty.Close() }()
+	pty, tty := openClose(t)
 
 	ttyFile, err := os.OpenFile(tty.Name(), os.O_RDWR, 0o600)
 	if err != nil {
@@ -96,10 +90,7 @@ func TestOpenByName(t *testing.T) {
 func TestGetsize(t *testing.T) {
 	t.Parallel()
 
-	pty, tty, err := Open()
-	if err != nil {
-		t.Fatalf("Unexpected error from Open: %s.", err)
-	}
+	pty, tty := openClose(t)
 
 	prows, pcols, err := Getsize(pty)
 	if err != nil {
@@ -117,23 +108,12 @@ func TestGetsize(t *testing.T) {
 	if prows != trows {
 		t.Errorf("pty cols != tty cols: %d != %d.", pcols, tcols)
 	}
-
-	if err := tty.Close(); err != nil {
-		t.Errorf("Unexpected error from tty Close: %s.", err)
-	}
-
-	if err := pty.Close(); err != nil {
-		t.Errorf("Unexpected error from pty Close: %s.", err)
-	}
 }
 
 func TestGetsizefull(t *testing.T) {
 	t.Parallel()
 
-	pty, tty, err := Open()
-	if err != nil {
-		t.Fatalf("Unexpected error from Open: %s.", err)
-	}
+	pty, tty := openClose(t)
 
 	psize, err := GetsizeFull(pty)
 	if err != nil {
@@ -157,23 +137,12 @@ func TestGetsizefull(t *testing.T) {
 	if psize.Cols != tsize.Cols {
 		t.Errorf("pty cols != tty cols: %d != %d.", psize.Cols, tsize.Cols)
 	}
-
-	if err := tty.Close(); err != nil {
-		t.Errorf("Unexpected error from tty Close: %s.", err)
-	}
-
-	if err := pty.Close(); err != nil {
-		t.Errorf("Unexpected error from pty Close: %s.", err)
-	}
 }
 
 func TestSetsize(t *testing.T) {
 	t.Parallel()
 
-	pty, tty, err := Open()
-	if err != nil {
-		t.Fatalf("Unexpected error from Open: %s.", err)
-	}
+	pty, tty := openClose(t)
 
 	psize, err := GetsizeFull(pty)
 	if err != nil {
@@ -206,29 +175,18 @@ func TestSetsize(t *testing.T) {
 	if psize.Cols != tsize.Cols {
 		t.Errorf("pty cols != tty cols: %d != %d.", psize.Cols, tsize.Cols)
 	}
-
-	if err := tty.Close(); err != nil {
-		t.Errorf("Unexpected error from tty Close: %s.", err)
-	}
-
-	if err := pty.Close(); err != nil {
-		t.Errorf("Unexpected error from pty Close: %s.", err)
-	}
 }
 
 func TestReadWriteText(t *testing.T) {
 	t.Parallel()
 
-	pty, tty, err := Open()
-	if err != nil {
-		t.Fatalf("Unexpected error from Open: %s.", err)
-	}
+	pty, tty := openClose(t)
 
 	// Write to tty, read from pty
 	text := []byte("ping")
 	n, err := tty.Write(text)
 	if err != nil {
-		t.Errorf("Unexpected error from Write: %s", err)
+		t.Fatalf("Unexpected error from Write: %s", err)
 	}
 	if n != len(text) {
 		t.Errorf("Unexpected count returned from Write, got %d expected %d.", n, len(text))
@@ -256,7 +214,7 @@ func TestReadWriteText(t *testing.T) {
 	buffer = make([]byte, 5)
 	err = readBytes(tty, buffer)
 	if err != nil {
-		t.Errorf("Unexpected error from readBytes: %s.", err)
+		t.Fatalf("Unexpected error from readBytes: %s.", err)
 	}
 	expect := []byte("pong\n")
 	if !bytes.Equal(expect, buffer) {
@@ -273,25 +231,12 @@ func TestReadWriteText(t *testing.T) {
 	if !bytes.Equal(expect, buffer) {
 		t.Errorf("Unexpected result returned from Read, got %v expected %v.", buffer, expect)
 	}
-
-	err = tty.Close()
-	if err != nil {
-		t.Errorf("Unexpected error from tty Close: %s.", err)
-	}
-
-	err = pty.Close()
-	if err != nil {
-		t.Errorf("Unexpected error from pty Close: %s.", err)
-	}
 }
 
 func TestReadWriteControls(t *testing.T) {
 	t.Parallel()
 
-	pty, tty, err := Open()
-	if err != nil {
-		t.Fatalf("Unexpected error from Open: %s.", err)
-	}
+	pty, tty := openClose(t)
 
 	// Write the start of a line to pty.
 	text := []byte("pind")
@@ -342,12 +287,4 @@ func TestReadWriteControls(t *testing.T) {
 	if !bytes.Equal(expect, buffer) {
 		t.Errorf("Unexpected result returned from Read, got %v expected %v.", buffer, expect)
 	}
-
-	if err := tty.Close(); err != nil {
-		t.Errorf("Unexpected error from tty Close: %s.", err)
-	}
-
-	if err := pty.Close(); err != nil {
-		t.Errorf("Unexpected error from pty Close: %s.", err)
-	}
 }

From 219f7e0db96efd51edb48aae71bf77a427209710 Mon Sep 17 00:00:00 2001
From: "Guillaume J. Charmes" <git+guillaume@charmes.net>
Date: Tue, 31 Oct 2023 10:46:02 -0400
Subject: [PATCH 3/5] Add more test helpers, cleanup existing tests. Add
 editorconfig and golangci config, comply with golangci rules.

---
 .editorconfig        |  54 ++++++++
 .golangci.yml        | 324 +++++++++++++++++++++++++++++++++++++++++++
 doc_test.go          | 262 ++++++++++------------------------
 helpers_test.go      |  62 +++++++++
 io_test.go           |  13 +-
 ioctl.go             |   4 +-
 ioctl_inner.go       |   3 +-
 ioctl_legacy.go      |   2 +-
 ioctl_solaris.go     |   2 +-
 ioctl_unsupported.go |   2 +-
 pty_linux.go         |   2 +-
 winsize.go           |   5 +-
 winsize_unix.go      |   8 +-
 13 files changed, 534 insertions(+), 209 deletions(-)
 create mode 100644 .editorconfig
 create mode 100644 .golangci.yml
 create mode 100644 helpers_test.go

diff --git a/.editorconfig b/.editorconfig
new file mode 100644
index 0000000..349f67a
--- /dev/null
+++ b/.editorconfig
@@ -0,0 +1,54 @@
+root = true
+
+# Sane defaults.
+[*]
+# Always use unix end of line.
+end_of_line              = lf
+# Always insert a new line at the end of files.
+insert_final_newline     = true
+# Don't leave trailing whitespaces.
+trim_trailing_whitespace = true
+# Default to utf8 encoding.
+charset                  = utf-8
+# Space > tab for consistent aligns.
+indent_style             = space
+# Default to 2 spaces for indent/tabs.
+indent_size              = 2
+# Flag long lines.
+max_line_length          = 140
+
+# Explicitly define settings for commonly used files.
+
+[*.go]
+indent_style = tab
+indent_size  = 8
+
+[*.feature]
+indent_style = space
+indent_size  = 2
+
+[*.json]
+indent_style = space
+indent_size  = 2
+
+[*.{yml,yaml}]
+indent_style = space
+indent_size  = 2
+
+[*.tf]
+indent_style = space
+indent_size  = 2
+
+[*.md]
+# Don't check line lenghts in files.
+max_line_length = 0
+
+[{Makefile,*.mk}]
+indent_style = tab
+indent_size  = 8
+
+[{Dockerfile,Dockerfile.*}]
+indent_size = 4
+
+[*.sql]
+indent_size = 2
diff --git a/.golangci.yml b/.golangci.yml
new file mode 100644
index 0000000..f023e0f
--- /dev/null
+++ b/.golangci.yml
@@ -0,0 +1,324 @@
+---
+# Reference: https://golangci-lint.run/usage/configuration/
+run:
+  timeout: 5m
+  # modules-download-mode: vendor
+
+  # Include test files.
+  tests: true
+
+  skip-dirs: []
+
+  skip-files: []
+
+output:
+  # colored-line-number|line-number|json|tab|checkstyle|code-climate, default is "colored-line-number".
+  format: colored-line-number
+  print-issued-lines: true
+  print-linter-name: true
+
+# Linter specific settings. See below in the `linter.enable` section for details on what each linter is doing.
+linters-settings:
+  dogsled:
+    # Checks assignments with too many blank identifiers. Default is 2.
+    max-blank-identifiers: 2
+
+  dupl:
+    # Tokens count to trigger issue.
+    threshold: 150
+
+  errcheck:
+    # Report about not checking of errors in type assertions: `a := b.(MyStruct)`.
+    # Enabled as this is often overlooked by developers.
+    check-type-assertions: true
+    # Report about assignment of errors to blank identifier: `num, _ := strconv.Atoi(numStr)`.
+    # Disabled as we consider that if the developer did type `_`, it was on purpose.
+    # Note that while this isn't enforced by the linter, each and every case of ignored error should
+    # be accompanied with a comment explaining why that error is being discarded.
+    check-blank: false
+
+  exhaustive:
+    # Indicates that switch statements are to be considered exhaustive if a
+    # 'default' case is present, even if all enum members aren't listed in the
+    # switch.
+    default-signifies-exhaustive: false
+
+  funlen:
+    # funlen checks the number of lines/statements in a function.
+    # While is is always best to keep functions short for readability, maintainability and testing,
+    # the default are a bit too strict (60 lines / 40 statements), increase it to be more flexible.
+    lines: 160
+    statements: 70
+
+  # NOTE: We don't set `gci` for import order as it supports only one prefix. Use `goimports.local-prefixes` instead.
+
+  gocognit:
+    # Minimal code complexity to report, defaults to 30 in gocognit, defaults 10 in golangci.
+    # Use 15 as it allows for some flexibility while preventing too much complexity.
+    # NOTE: Similar to gocyclo.
+    min-complexity: 35
+
+  nestif:
+    # Minimal complexity of if statements to report.
+    min-complexity: 8
+
+  goconst:
+    # Minimal length of string constant.
+    min-len: 4
+    # Minimal occurrences count to trigger.
+    # Increase the default from 3 to 5 as small number of const usage can reduce readability instead of improving it.
+    min-occurrences: 5
+
+  gocritic:
+    # Which checks should be disabled; can't be combined with 'enabled-checks'.
+    # See https://go-critic.github.io/overview#checks-overview
+    # To check which checks are enabled run `GL_DEBUG=gocritic golangci-lint run`
+    disabled-checks:
+      - hugeParam  # Very strict check on the size of variables being copied. Too strict for most developer.
+    # Enable multiple checks by tags, run `GL_DEBUG=gocritic golangci-lint run` to see all tags and checks.
+    # Empty list by default. See https://github.com/go-critic/go-critic#usage -> section "Tags".
+    enabled-tags:
+      - diagnostic
+      - style
+      - opinionated
+      - performance
+    settings:
+      rangeValCopy:
+        sizeThreshold: 1024  # Increase the allowed copied bytes in range.
+
+  cyclop:
+    max-complexity: 35
+
+  gocyclo:
+    # Similar check as gocognit.
+    # NOTE: We might be able to remove this linter as it is redundant with gocyclo. It is in golangci-lint, so we keep it for now.
+    min-complexity: 35
+
+  godot:
+    # Check all top-level comments, not only declarations.
+    check-all: true
+
+  gofmt:
+    # simplify code: gofmt with `-s` option.
+    simplify: true
+
+  # NOTE: the goheader settings are set per-project.
+
+  goimports:
+    # Put imports beginning with prefix after 3rd-party packages.
+    # It's a comma-separated list of prefixes.
+    local-prefixes: "github.com/creack/pty"
+
+  golint:
+    # Minimal confidence for issues, default is 0.8.
+    min-confidence: 0.8
+
+  gosimple:
+    # Select the Go version to target. The default is '1.13'.
+    go: "1.18"
+    # https://staticcheck.io/docs/options#checks
+    checks: ["all"]
+
+  gosec:
+
+  govet:
+    # Enable all available checks from go vet.
+    enable-all: false
+    # Report about shadowed variables.
+    check-shadowing: true
+
+  # NOTE: depguard is disabled as it is very slow and made redundant by gomodguard.
+
+  lll:
+    # Make sure everyone is on the same level, fix the tab width to go's default.
+    tab-width: 8
+    # Increase the default max line length to give more flexibility. Forcing newlines can reduce readability instead of improving it.
+    line-length: 180
+
+  misspell:
+    locale: US
+    ignore-words:
+
+  nakedret:
+    # Make an issue if func has more lines of code than this setting and it has naked returns; default is 30.
+    # NOTE: Consider setting this to 1 to prevent naked returns.
+    max-func-lines: 30
+
+  nolintlint:
+    # Prevent ununsed directive to avoid stale comments.
+    allow-unused: false
+    # Require an explanation of nonzero length after each nolint directive.
+    require-explanation: true
+    # Exclude following linters from requiring an explanation.
+    # NOTE: It is strongly discouraged to put anything in there.
+    allow-no-explanation: []
+    # Enable to require nolint directives to mention the specific linter being suppressed. This ensurce the developer understand the reason being the error.
+    require-specific: true
+
+  prealloc:
+    # NOTE: For most programs usage of prealloc will be a premature optimization.
+    #       Keep thing simple, pre-alloc what is obvious and profile the program for more complex scenarios.
+    #
+    simple: true       # Checkonly on simple loops that have no returns/breaks/continues/gotos in them.
+    range-loops: true  # Check range loops, true by default
+    for-loops: false   # Check suggestions on for loops, false by default
+
+  rowserrcheck:
+    packages: []
+
+  staticcheck:
+    # Select the Go version to target. The default is '1.13'.
+    go: "1.18"
+    # https://staticcheck.io/docs/options#checks
+    checks: ["all"]
+
+  stylecheck:
+    # Select the Go version to target. The default is '1.13'.
+    go: "1.18"
+    # https://staticcheck.io/docs/options#checks
+    checks: ["all"]  # "-ST1000", "-ST1003", "-ST1016", "-ST1020", "-ST1021", "-ST1022"]
+
+  tagliatelle:
+    # Check the struck tag name case.
+    case:
+      # Use the struct field name to check the name of the struct tag.
+      use-field-name: false
+      rules:
+        # Any struct tag type can be used.
+        # support string case: `camel`, `pascal`, `kebab`, `snake`, `goCamel`, `goPascal`, `goKebab`, `goSnake`, `upper`, `lower`
+        json: snake
+        firestore: camel
+        yaml: camel
+        xml: camel
+        bson: camel
+        avro: snake
+        mapstructure: kebab
+        envconfig: upper
+
+  unparam:
+    # Don't create an error if an exported code have static params being used. It is often expected in libraries.
+    # NOTE: It would be nice if this linter would differentiate between a main package and a lib.
+    check-exported: true
+
+  unused: {}
+
+  whitespace:
+    multi-if: false    # Enforces newlines (or comments) after every multi-line if statement
+    multi-func: false  # Enforces newlines (or comments) after every multi-line function signature
+
+# Run `golangci-lint help linters` to get the full list of linter with their description.
+linters:
+  disable-all: true
+  # NOTE: enable-all is deprecated because too  many people don't pin versions...
+  # We still require explicit documentation on why some linters are disabled.
+  # disable:
+  #   - depguard          # Go linter that checks if package imports are in a list of acceptable packages [fast: true, auto-fix: false]
+  #   - exhaustivestruct  # Checks if all struct's fields are initialized [fast: true, auto-fix: false]
+  #   - forbidigo         # Forbids identifiers [fast: true, auto-fix: false]
+  #   - gci               # Gci control golang package import order and make it always deterministic. [fast: true, auto-fix: true]
+  #   - godox             # Tool for detection of FIXME, TODO and other comment keywords [fast: true, auto-fix: false]
+  #   - goerr113          # Golang linter to check the errors handling expressions [fast: true, auto-fix: false]
+  #   - golint            # Golint differs from gofmt. Gofmt reformats Go source code, whereas golint prints out style mistakes [fast: false, auto-fix: false]
+  #   - gomnd             # An analyzer to detect magic numbers. [fast: true, auto-fix: false]
+  #   - gomoddirectives   # Manage the use of 'replace', 'retract', and 'excludes' directives in go.mod. [fast: true, auto-fix: false]
+  #   - interfacer        # Linter that suggests narrower interface types [fast: false, auto-fix: false]
+  #   - maligned          # Tool to detect Go structs that would take less memory if their fields were sorted [fast: false, auto-fix: false]
+  #   - nlreturn          # nlreturn checks for a new line before return and branch statements to increase code clarity [fast: true, auto-fix: false]
+  #   - scopelint         # Scopelint checks for unpinned variables in go programs [fast: true, auto-fix: false]
+  #   - wrapcheck         # Checks that errors returned from external packages are wrapped [fast: false, auto-fix: false]
+  #   - wsl               # Whitespace Linter - Forces you to use empty lines! [fast: true, auto-fix: false]
+
+  # disable-reasons:
+  #   - depguard          # Checks whitelisted/blacklisted import path, but runs way too slow. Not that useful.
+  #   - exhaustivestruct  # Good concept, but not mature enough (errors on not assignable fields like locks) and too noisy when using AWS SDK as most fields are unused.
+  #   - forbidigo         # Great idea, but too strict out of the box. Probably will re-enable soon.
+  #   - gci               # Conflicts with goimports/gofumpt.
+  #   - godox             # Don't fail when finding TODO, FIXME, etc.
+  #   - goerr113          # Too many false positives.
+  #   - golint            # Deprecated (since v1.41.0) due to: The repository of the linter has been archived by the owner.  Replaced by revive.
+  #   - gomnd             # Checks for magic numbers. Disabled due to too many false positives not configurable (03/01/2020 v1.23.7).
+  #   - gomoddirectives   # Doesn't support //nolint to whitelist.
+  #   - interfacer        # Deprecated (since v1.38.0) due to: The repository of the linter has been archived by the owner.
+  #   - maligned          # Deprecated (since v1.38.0) due to: The repository of the linter has been archived by the owner.  Replaced by govet 'fieldalignment'.
+  #   - nlreturn          # Actually reduces readability in most cases.
+  #   - scopelint         # Deprecated (since v1.39.0) due to: The repository of the linter has been deprecated by the owner.  Replaced by exportloopref.
+  #   - wrapcheck         # Good concept, but always warns for http coded errors. Need to re-enable and whitelist our error package.
+  #   - wsl               # Forces to add newlines around blocks. Lots of false positives, not that useful.
+
+  enable:
+    - asciicheck        # Simple linter to check that your code does not contain non-ASCII identifiers [fast: true, auto-fix: false]
+    - bodyclose         # checks whether HTTP response body is closed successfully [fast: false, auto-fix: false]
+    - cyclop            # checks function and package cyclomatic complexity [fast: false, auto-fix: false]
+    - dogsled           # Checks assignments with too many blank identifiers (e.g. x, _, _, _, := f()) [fast: true, auto-fix: false]
+    - dupl              # Tool for code clone detection [fast: true, auto-fix: false]
+    - durationcheck     # check for two durations multiplied together [fast: false, auto-fix: false]
+    - errcheck          # Errcheck is a program for checking for unchecked errors in go programs. These unchecked errors can be critical bugs in some cases [fast: false, auto-fix: false]
+    - errname           # Checks that sentinel errors are prefixed with the `Err` and error types are suffixed with the `Error`. [fast: false, auto-fix: false]
+    - errorlint         # go-errorlint is a source code linter for Go software that can be used to find code that will cause problems with the error wrapping scheme introduced in Go 1.13. [fast: false, auto-fix: false]
+    - exhaustive        # check exhaustiveness of enum switch statements [fast: false, auto-fix: false]
+    - exportloopref     # checks for pointers to enclosing loop variables [fast: false, auto-fix: false]
+    - forcetypeassert   # finds forced type assertions [fast: true, auto-fix: false]
+    - funlen            # Tool for detection of long functions [fast: true, auto-fix: false]
+    - gochecknoglobals  # check that no global variables exist [fast: true, auto-fix: false]
+    - gochecknoinits    # Checks that no init functions are present in Go code [fast: true, auto-fix: false]
+    - gocognit          # Computes and checks the cognitive complexity of functions [fast: true, auto-fix: false]
+    - goconst           # Finds repeated strings that could be replaced by a constant [fast: true, auto-fix: false]
+    - gocritic          # Provides many diagnostics that check for bugs, performance and style issues. [fast: false, auto-fix: false]
+    - gocyclo           # Computes and checks the cyclomatic complexity of functions [fast: true, auto-fix: false]
+    - godot             # Check if comments end in a period [fast: true, auto-fix: true]
+    - gofmt             # Gofmt checks whether code was gofmt-ed. By default this tool runs with -s option to check for code simplification [fast: true, auto-fix: true]
+    - gofumpt           # Gofumpt checks whether code was gofumpt-ed. [fast: true, auto-fix: true]
+    - goheader          # Checks is file header matches to pattern [fast: true, auto-fix: false]
+    - goimports         # Goimports does everything that gofmt does. Additionally it checks unused imports [fast: true, auto-fix: true]
+    - gomodguard        # Allow and block list linter for direct Go module dependencies. This is different from depguard where there are different block types for example version constraints and module recommendations. [fast: true, auto-fix: false]
+    - goprintffuncname  # Checks that printf-like functions are named with `f` at the end [fast: true, auto-fix: false]
+    - gosec             # (gas): Inspects source code for security problems [fast: false, auto-fix: false]
+    - gosimple          # (megacheck): Linter for Go source code that specializes in simplifying a code [fast: false, auto-fix: false]
+    - govet             # (vet, vetshadow): Vet examines Go source code and reports suspicious constructs, such as Printf calls whose arguments do not align with the format string [fast: false, auto-fix: false]
+    - importas          # Enforces consistent import aliases [fast: false, auto-fix: false]
+    - ineffassign       # Detects when assignments to existing variables are not used [fast: true, auto-fix: false]
+    - lll               # Reports long lines [fast: true, auto-fix: false]
+    - makezero          # Finds slice declarations with non-zero initial length [fast: false, auto-fix: false]
+    - misspell          # Finds commonly misspelled English words in comments [fast: true, auto-fix: true]
+    - nakedret          # Finds naked returns in functions greater than a specified function length [fast: true, auto-fix: false]
+    - nestif            # Reports deeply nested if statements [fast: true, auto-fix: false]
+    - nilerr            # Finds the code that returns nil even if it checks that the error is not nil. [fast: false, auto-fix: false]
+    - noctx             # noctx finds sending http request without context.Context [fast: false, auto-fix: false]
+    - nolintlint        # Reports ill-formed or insufficient nolint directives [fast: true, auto-fix: false]
+    - paralleltest      # paralleltest detects missing usage of t.Parallel() method in your Go test [fast: true, auto-fix: false]
+    - prealloc          # Finds slice declarations that could potentially be preallocated [fast: true, auto-fix: false]
+    - predeclared       # find code that shadows one of Go's predeclared identifiers [fast: true, auto-fix: false]
+    - promlinter        # Check Prometheus metrics naming via promlint [fast: true, auto-fix: false]
+    - revive            # Fast, configurable, extensible, flexible, and beautiful linter for Go. Drop-in replacement of golint. [fast: false, auto-fix: false]
+    # Disabled due to generic. Work in progress upstream.
+    # - rowserrcheck      # checks whether Err of rows is checked successfully [fast: false, auto-fix: false]
+    # Disabled due to generic. Work in progress upstream.
+    # - sqlclosecheck     # Checks that sql.Rows and sql.Stmt are closed. [fast: false, auto-fix: false]
+    - staticcheck       # (megacheck): Staticcheck is a go vet on steroids, applying a ton of static analysis checks [fast: false, auto-fix: false]
+    - stylecheck        # Stylecheck is a replacement for golint [fast: false, auto-fix: false]
+    # Disabled due to generic. Work in progress upstream.
+    # - tagliatelle       # Checks the struct tags. [fast: true, auto-fix: false]
+    # - testpackage       # linter that makes you use a separate _test package [fast: true, auto-fix: false]
+    - thelper           # thelper detects golang test helpers without t.Helper() call and checks the consistency of test helpers [fast: false, auto-fix: false]
+    - tparallel         # tparallel detects inappropriate usage of t.Parallel() method in your Go test codes [fast: false, auto-fix: false]
+    - typecheck         # Like the front-end of a Go compiler, parses and type-checks Go code [fast: false, auto-fix: false]
+    - unconvert         # Remove unnecessary type conversions [fast: false, auto-fix: false]
+    - unparam           # Reports unused function parameters [fast: false, auto-fix: false]
+    # Disabled due to way too many false positive in go1.20.
+    # - unused            # (megacheck): Checks Go code for unused constants, variables, functions and types [fast: false, auto-fix: false]
+    # Disabled due to generic. Work in progress upstream.
+    # - wastedassign      # wastedassign finds wasted assignment statements. [fast: false, auto-fix: false]
+    - whitespace        # Tool for detection of leading and trailing whitespace [fast: true, auto-fix: true]
+
+issues:
+  exclude:
+    # Allow shadowing of 'err'.
+    - 'shadow: declaration of "err" shadows declaration'
+    # Allow shadowing of `ctx`.
+    - 'shadow: declaration of "ctx" shadows declaration'
+  # Maximum issues count per one linter. Set to 0 to disable. Default is 50.
+  max-per-linter: 10
+  # Disable default excludes. Always be explicit on what we exclude.
+  exclude-use-default: false
+  # Exclude some linters from running on tests files.
+  exclude-rules: []
diff --git a/doc_test.go b/doc_test.go
index 6e5916e..ac67e82 100644
--- a/doc_test.go
+++ b/doc_test.go
@@ -1,39 +1,10 @@
 package pty
 
 import (
-	"bytes"
-	"io"
 	"os"
 	"testing"
 )
 
-// Will fill p from reader r.
-func readBytes(r io.Reader, p []byte) error {
-	_, err := io.ReadFull(r, p)
-	return err
-}
-
-// openCloses opens a pty/tty pair and stages the closing as part of the cleanup.
-func openClose(t *testing.T) (pty, tty *os.File) {
-	t.Helper()
-
-	pty, tty, err := Open()
-	if err != nil {
-		t.Fatalf("Unexpected error from Open: %s.", err)
-	}
-	t.Cleanup(func() {
-		if err := tty.Close(); err != nil {
-			t.Errorf("Unexpected error from tty Close: %s.", err)
-		}
-
-		if err := pty.Close(); err != nil {
-			t.Errorf("Unexpected error from pty Close: %s.", err)
-		}
-	})
-
-	return pty, tty
-}
-
 func TestOpen(t *testing.T) {
 	t.Parallel()
 
@@ -60,31 +31,22 @@ func TestName(t *testing.T) {
 func TestOpenByName(t *testing.T) {
 	t.Parallel()
 
-	pty, tty := openClose(t)
+	pty, tty := openClose(t) // Get the pty/tty pair.
 
+	// Manually open the tty from the exiting name.
 	ttyFile, err := os.OpenFile(tty.Name(), os.O_RDWR, 0o600)
-	if err != nil {
-		t.Fatalf("Failed to open tty file: %s.", err)
-	}
+	noError(t, err, "Failed to open tty file")
 	defer func() { _ = ttyFile.Close() }()
 
 	// Ensure we can write to the newly opened tty file and read on the pty.
 	text := []byte("ping")
-	n, err := ttyFile.Write(text)
-	if err != nil {
-		t.Fatalf("Unexpected error from Write: %s.", err)
-	}
-	if n != len(text) {
-		t.Errorf("Unexpected count returned from Write, got %d expected %d.", n, len(text))
-	}
 
-	buffer := make([]byte, len(text))
-	if err := readBytes(pty, buffer); err != nil {
-		t.Fatalf("Unexpected error from readBytes: %s.", err)
-	}
-	if !bytes.Equal(text, buffer) {
-		t.Errorf("Unexpected result returned from Read, got %v expected %v", buffer, text)
-	}
+	n, err := ttyFile.Write(text)                                   // Write the text to the manually open tty.
+	noError(t, err, "Unexpected error from Write")                  // Make sure it didn't fail.
+	assert(t, len(text), n, "Unexpected count returned from Write") // Assert the number of bytes written.
+
+	buffer := readN(t, pty, len(text), "Unexpected error from pty Read")
+	assertBytes(t, text, buffer, "Unexpected result result returned from pty Read")
 }
 
 func TestGetsize(t *testing.T) {
@@ -93,50 +55,30 @@ func TestGetsize(t *testing.T) {
 	pty, tty := openClose(t)
 
 	prows, pcols, err := Getsize(pty)
-	if err != nil {
-		t.Errorf("Unexpected error from Getsize: %s.", err)
-	}
+	noError(t, err, "Unexpected error from pty Getsize")
 
 	trows, tcols, err := Getsize(tty)
-	if err != nil {
-		t.Errorf("Unexpected error from Getsize: %s.", err)
-	}
+	noError(t, err, "Unexpected error from tty Getsize")
 
-	if prows != trows {
-		t.Errorf("pty rows != tty rows: %d != %d.", prows, trows)
-	}
-	if prows != trows {
-		t.Errorf("pty cols != tty cols: %d != %d.", pcols, tcols)
-	}
+	assert(t, prows, trows, "rows from Getsize on pty and tty should match")
+	assert(t, pcols, tcols, "cols from Getsize on pty and tty should match")
 }
 
-func TestGetsizefull(t *testing.T) {
+func TestGetsizeFull(t *testing.T) {
 	t.Parallel()
 
 	pty, tty := openClose(t)
 
 	psize, err := GetsizeFull(pty)
-	if err != nil {
-		t.Fatalf("Unexpected error from GetsizeFull: %s.", err)
-	}
+	noError(t, err, "Unexpected error from pty GetsizeFull")
 
 	tsize, err := GetsizeFull(tty)
-	if err != nil {
-		t.Fatalf("Unexpected error from GetsizeFull: %s.", err)
-	}
+	noError(t, err, "Unexpected error from tty GetsizeFull")
 
-	if psize.X != tsize.X {
-		t.Errorf("pty x != tty x: %d != %d.", psize.X, tsize.X)
-	}
-	if psize.Y != tsize.Y {
-		t.Errorf("pty y != tty y: %d != %d.", psize.Y, tsize.Y)
-	}
-	if psize.Rows != tsize.Rows {
-		t.Errorf("pty rows != tty rows: %d != %d.", psize.Rows, tsize.Rows)
-	}
-	if psize.Cols != tsize.Cols {
-		t.Errorf("pty cols != tty cols: %d != %d.", psize.Cols, tsize.Cols)
-	}
+	assert(t, psize.X, tsize.X, "X from GetsizeFull on pty and tty should match")
+	assert(t, psize.Y, tsize.Y, "Y from GetsizeFull on pty and tty should match")
+	assert(t, psize.Rows, tsize.Rows, "rows from GetsizeFull on pty and tty should match")
+	assert(t, psize.Cols, tsize.Cols, "cols from GetsizeFull on pty and tty should match")
 }
 
 func TestSetsize(t *testing.T) {
@@ -145,36 +87,22 @@ func TestSetsize(t *testing.T) {
 	pty, tty := openClose(t)
 
 	psize, err := GetsizeFull(pty)
-	if err != nil {
-		t.Fatalf("Unexpected error from GetsizeFull: %s.", err)
-	}
+	noError(t, err, "Unexpected error from pty GetsizeFull")
 
-	psize.X = psize.X + 1
-	psize.Y = psize.Y + 1
-	psize.Rows = psize.Rows + 1
-	psize.Cols = psize.Cols + 1
+	psize.X++
+	psize.Y++
+	psize.Rows++
+	psize.Cols++
 
-	if err := Setsize(tty, psize); err != nil {
-		t.Fatalf("Unexpected error from Setsize: %s", err)
-	}
+	noError(t, Setsize(tty, psize), "Unexpected error from Setsize")
 
 	tsize, err := GetsizeFull(tty)
-	if err != nil {
-		t.Fatalf("Unexpected error from GetsizeFull: %s.", err)
-	}
+	noError(t, err, "Unexpected error from tty GetsizeFull")
 
-	if psize.X != tsize.X {
-		t.Errorf("pty x != tty x: %d != %d.", psize.X, tsize.X)
-	}
-	if psize.Y != tsize.Y {
-		t.Errorf("pty y != tty y: %d != %d.", psize.Y, tsize.Y)
-	}
-	if psize.Rows != tsize.Rows {
-		t.Errorf("pty rows != tty rows: %d != %d.", psize.Rows, tsize.Rows)
-	}
-	if psize.Cols != tsize.Cols {
-		t.Errorf("pty cols != tty cols: %d != %d.", psize.Cols, tsize.Cols)
-	}
+	assert(t, psize.X, tsize.X, "Unexpected Getsize X result after Setsize")
+	assert(t, psize.Y, tsize.Y, "Unexpected Getsize Y result after Setsize")
+	assert(t, psize.Rows, tsize.Rows, "Unexpected Getsize Rows result after Setsize")
+	assert(t, psize.Cols, tsize.Cols, "Unexpected Getsize Cols result after Setsize")
 }
 
 func TestReadWriteText(t *testing.T) {
@@ -182,54 +110,35 @@ func TestReadWriteText(t *testing.T) {
 
 	pty, tty := openClose(t)
 
-	// Write to tty, read from pty
-	text := []byte("ping")
-	n, err := tty.Write(text)
-	if err != nil {
-		t.Fatalf("Unexpected error from Write: %s", err)
-	}
-	if n != len(text) {
-		t.Errorf("Unexpected count returned from Write, got %d expected %d.", n, len(text))
-	}
+	// Write to tty, read from pty.
+	{
+		text := []byte("ping")
 
-	buffer := make([]byte, 4)
-	if err := readBytes(pty, buffer); err != nil {
-		t.Fatalf("Unexpected error from readBytes: %s.", err)
-	}
-	if !bytes.Equal(text, buffer) {
-		t.Errorf("Unexpected result returned from Read, got %v expected %v.", buffer, text)
+		n, err := tty.Write(text)
+		noError(t, err, "Unexpected error from tty Write")
+		assert(t, n, len(text), "Unexpected count returned from tty Write")
+
+		buffer := readN(t, pty, len(text), "Unexpected error from pty Read")
+		assertBytes(t, text, buffer, "Unexpected result returned from pty Read")
 	}
 
 	// Write to pty, read from tty.
 	// We need to send a \n otherwise this will block in the terminal driver.
-	text = []byte("pong\n")
-	n, err = pty.Write(text)
-	if err != nil {
-		t.Fatalf("Unexpected error from Write: %s.", err)
-	}
-	if n != len(text) {
-		t.Errorf("Unexpected count returned from Write, got %d expected %d.", n, len(text))
-	}
+	{
+		text := []byte("pong\n")
 
-	buffer = make([]byte, 5)
-	err = readBytes(tty, buffer)
-	if err != nil {
-		t.Fatalf("Unexpected error from readBytes: %s.", err)
-	}
-	expect := []byte("pong\n")
-	if !bytes.Equal(expect, buffer) {
-		t.Errorf("Unexpected result returned from Read, got %v expected %v.", buffer, expect)
-	}
+		n, err := pty.Write(text)
+		noError(t, err, "Unexpected error from pty Write")
+		assert(t, n, len(text), "Unexpected count returned from pty Write")
 
-	// Read the echo back from pty
-	buffer = make([]byte, 5)
-	err = readBytes(pty, buffer)
-	if err != nil {
-		t.Fatalf("Unexpected error from readBytes: %s.", err)
-	}
-	expect = []byte("pong\r")
-	if !bytes.Equal(expect, buffer) {
-		t.Errorf("Unexpected result returned from Read, got %v expected %v.", buffer, expect)
+		// Expect the raw text back when reading from tty.
+		buffer := readN(t, tty, len(text), "Unexpected error from tty Read")
+		assertBytes(t, text, buffer, "Unexpected result returned from tty Read")
+
+		// Read the echo back from pty. Expect LF to be CRLF.
+		expect := []byte("pong\r\n")
+		buffer = readN(t, pty, len(expect), "Unexpected error from pty Read")
+		assertBytes(t, expect, buffer, "Unexpected result returned from pty Read")
 	}
 }
 
@@ -239,52 +148,25 @@ func TestReadWriteControls(t *testing.T) {
 	pty, tty := openClose(t)
 
 	// Write the start of a line to pty.
-	text := []byte("pind")
-	n, err := pty.Write(text)
-	if err != nil {
-		t.Fatalf("Unexpected error from Write: %s.", err)
-	}
-	if n != len(text) {
-		t.Errorf("Unexpected count returned from Write, got %d expected %d.", n, len(text))
-	}
+	n, err := pty.WriteString("pind")                                    // Intentional typo.
+	noError(t, err, "Unexpected error from Write initial text")          // Make sure it didn't fail.
+	assert(t, 4, n, "Unexpected count returned from Write initial text") // Assert the number of bytes written.
 
 	// Backspace that last char.
-	n, err = pty.Write([]byte("\b"))
-	if err != nil {
-		t.Fatalf("Unexpected error from Write: %s.", err)
-	}
-	if n != 1 {
-		t.Errorf("Unexpected count returned from Write, got %d expected %d.", n, 1)
-	}
-
-	// Write the correct char and a CR.
-	n, err = pty.Write([]byte("g\n"))
-	if err != nil {
-		t.Fatalf("Unexpected error from Write: %s.", err)
-	}
-	if n != 2 {
-		t.Errorf("Unexpected count returned from Write, got %d expected %d.", n, 2)
-	}
-
-	// Read the line
-	buffer := make([]byte, 7)
-	err = readBytes(tty, buffer)
-	if err != nil {
-		t.Errorf("Unexpected error from readBytes: %s.", err)
-	}
-	expect := []byte("pind\bg\n")
-	if !bytes.Equal(expect, buffer) {
-		t.Errorf("Unexpected result returned from Read, got %v expected %v.", buffer, expect)
-	}
-
-	// Read the echo back from pty
-	buffer = make([]byte, 7)
-	err = readBytes(pty, buffer)
-	if err != nil {
-		t.Errorf("Unexpected error from readBytes: %s.", err)
-	}
-	expect = []byte("pind^Hg")
-	if !bytes.Equal(expect, buffer) {
-		t.Errorf("Unexpected result returned from Read, got %v expected %v.", buffer, expect)
-	}
+	n, err = pty.WriteString("\b")                                    // "Remove" the typo.
+	noError(t, err, "Unexpected error from Write backspace")          // Make sure it didn't fail.
+	assert(t, 1, n, "Unexpected count returned from Write backspace") // Assert the number of bytes written.
+
+	// Write the correct char and a LF.
+	n, err = pty.WriteString("g\n")                                    // Fix the typo.
+	noError(t, err, "Unexpected error from Write fixed text")          // Make sure it didn't fail.
+	assert(t, 2, n, "Unexpected count returned from Write fixed text") // Assert the number of bytes written.
+
+	// Read the line.
+	buffer := readN(t, tty, 7, "Unexpected error from tty Read")
+	assertBytes(t, []byte("pind\bg\n"), buffer, "Unexpected result returned from tty Read")
+
+	// Read the echo back from pty.
+	buffer = readN(t, pty, 9, "Unexpected error from pty Read")
+	assertBytes(t, []byte("pind^Hg\r\n"), buffer, "Unexpected result returned from pty Read")
 }
diff --git a/helpers_test.go b/helpers_test.go
new file mode 100644
index 0000000..fbc98b7
--- /dev/null
+++ b/helpers_test.go
@@ -0,0 +1,62 @@
+package pty
+
+import (
+	"bytes"
+	"fmt"
+	"io"
+	"os"
+	"testing"
+)
+
+// openCloses opens a pty/tty pair and stages the closing as part of the cleanup.
+func openClose(t *testing.T) (pty, tty *os.File) {
+	t.Helper()
+
+	pty, tty, err := Open()
+	if err != nil {
+		t.Fatalf("Unexpected error from Open: %s.", err)
+	}
+	t.Cleanup(func() {
+		if err := tty.Close(); err != nil {
+			t.Errorf("Unexpected error from tty Close: %s.", err)
+		}
+
+		if err := pty.Close(); err != nil {
+			t.Errorf("Unexpected error from pty Close: %s.", err)
+		}
+	})
+
+	return pty, tty
+}
+
+func noError(t *testing.T, err error, msg string) {
+	t.Helper()
+	if err != nil {
+		t.Fatalf("%s: %s.", msg, err)
+	}
+}
+
+func assert[T comparable](t *testing.T, a, b T, msg string) {
+	t.Helper()
+	if a != b {
+		t.Errorf("%s: %v != %v.", msg, a, b)
+	}
+}
+
+// When asserting bytes, we want to display the diff, which may contain control characters.
+func assertBytes(t *testing.T, a, b []byte, msg string) {
+	t.Helper()
+	if !bytes.Equal(a, b) {
+		t.Errorf("%s: %v != %v.", msg, a, b)
+	}
+}
+
+// Read a specific number of bytes from r, assert it didn't fail and return the bytes.
+func readN(t *testing.T, r io.Reader, n int, msg string) []byte {
+	t.Helper()
+
+	buf := make([]byte, n)
+	_, err := io.ReadFull(r, buf)
+	noError(t, err, fmt.Sprintf("%s: %s", msg, err))
+	return buf
+}
diff --git a/io_test.go b/io_test.go
index 661559e..d448eb7 100644
--- a/io_test.go
+++ b/io_test.go
@@ -18,12 +18,15 @@ const (
 	timeout        = time.Second
 )
 
+//nolint:gochecknoglobals // Expected global lock to avodi potential race on (*os.File).Fd().
 var glTestFdLock sync.Mutex
 
 // Check that SetDeadline() works for ptmx.
 // Outstanding Read() calls must be interrupted by deadline.
 //
 // https://github.com/creack/pty/issues/162
+//
+//nolint:paralleltest // Potential in (*os.File).Fd().
 func TestReadDeadline(t *testing.T) {
 	ptmx, success := prepare(t)
 
@@ -51,6 +54,8 @@ func TestReadDeadline(t *testing.T) {
 //
 // https://github.com/creack/pty/issues/114
 // https://github.com/creack/pty/issues/88
+//
+//nolint:paralleltest // Potential in (*os.File).Fd().
 func TestReadClose(t *testing.T) {
 	ptmx, success := prepare(t)
 
@@ -73,7 +78,7 @@ func TestReadClose(t *testing.T) {
 	}
 }
 
-// Open pty and setup watchdogs for graceful and not so graceful failure modes
+// Open pty and setup watchdogs for graceful and not so graceful failure modes.
 func prepare(t *testing.T) (ptmx *os.File, done func()) {
 	t.Helper()
 
@@ -104,18 +109,18 @@ func prepare(t *testing.T) (ptmx *os.File, done func()) {
 		case <-ctx.Done():
 			// ptmx.Read() did not block forever, yay!
 		case <-time.After(timeout):
-			if _, err := pts.Write([]byte{errMarker}); err != nil { // unblock ptmx.Read()
+			if _, err := pts.Write([]byte{errMarker}); err != nil { // Unblock ptmx.Read().
 				t.Errorf("Failed to write to pts: %s.", err)
 			}
 			t.Error("ptmx.Read() was not unblocked.")
-			done() // cancel panic()
+			done() // Cancel panic().
 		}
 	}()
 	go func() {
 		select {
 		case <-ctx.Done():
 			// Test has either failed or succeeded; it definitely did not hang.
-		case <-time.After(timeout * 10 / 9): // timeout +11%
+		case <-time.After(timeout * 10 / 9): // Timeout + 11%.
 			panic("ptmx.Read() was not unblocked; avoid hanging forever.") // Just in case.
 		}
 	}()
diff --git a/ioctl.go b/ioctl.go
index 60ac9b8..021e4c7 100644
--- a/ioctl.go
+++ b/ioctl.go
@@ -8,13 +8,13 @@ import "os"
 func ioctl(f *os.File, cmd, ptr uintptr) error {
 	sc, e := f.SyscallConn()
 	if e != nil {
-		return ioctl_inner(f.Fd(), cmd, ptr) // fall back to blocking io (old behavior)
+		return ioctlInner(f.Fd(), cmd, ptr) // Fall back to blocking io (old behavior).
 	}
 
 	ch := make(chan error, 1)
 	defer close(ch)
 
-	e = sc.Control(func(fd uintptr) { ch <- ioctl_inner(fd, cmd, ptr) })
+	e = sc.Control(func(fd uintptr) { ch <- ioctlInner(fd, cmd, ptr) })
 	if e != nil {
 		return e
 	}
diff --git a/ioctl_inner.go b/ioctl_inner.go
index fd5dbef..272b50b 100644
--- a/ioctl_inner.go
+++ b/ioctl_inner.go
@@ -5,12 +5,13 @@ package pty
 
 import "syscall"
 
+// Local syscall const values.
 const (
 	TIOCGWINSZ = syscall.TIOCGWINSZ
 	TIOCSWINSZ = syscall.TIOCSWINSZ
 )
 
-func ioctl_inner(fd, cmd, ptr uintptr) error {
+func ioctlInner(fd, cmd, ptr uintptr) error {
 	_, _, e := syscall.Syscall(syscall.SYS_IOCTL, fd, cmd, ptr)
 	if e != 0 {
 		return e
diff --git a/ioctl_legacy.go b/ioctl_legacy.go
index f00b1a1..f7e923c 100644
--- a/ioctl_legacy.go
+++ b/ioctl_legacy.go
@@ -6,5 +6,5 @@ package pty
 import "os"
 
 func ioctl(f *os.File, cmd, ptr uintptr) error {
-	return ioctl_inner(f.Fd(), cmd, ptr) // fall back to blocking io (old behavior)
+	return ioctlInner(f.Fd(), cmd, ptr) // fall back to blocking io (old behavior)
 }
diff --git a/ioctl_solaris.go b/ioctl_solaris.go
index c0231df..6fd8bfe 100644
--- a/ioctl_solaris.go
+++ b/ioctl_solaris.go
@@ -40,7 +40,7 @@ type strioctl struct {
 // Defined in asm_solaris_amd64.s.
 func sysvicall6(trap, nargs, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2 uintptr, err syscall.Errno)
 
-func ioctl_inner(fd, cmd, ptr uintptr) error {
+func ioctlInner(fd, cmd, ptr uintptr) error {
 	if _, _, errno := sysvicall6(uintptr(unsafe.Pointer(&procioctl)), 3, fd, cmd, ptr, 0, 0, 0); errno != 0 {
 		return errno
 	}
diff --git a/ioctl_unsupported.go b/ioctl_unsupported.go
index 79ad4c6..e17908d 100644
--- a/ioctl_unsupported.go
+++ b/ioctl_unsupported.go
@@ -8,6 +8,6 @@ const (
 	TIOCSWINSZ = 0
 )
 
-func ioctl_inner(fd, cmd, ptr uintptr) error {
+func ioctlInner(fd, cmd, ptr uintptr) error {
 	return ErrUnsupported
 }
diff --git a/pty_linux.go b/pty_linux.go
index e12e2c8..e7e01c0 100644
--- a/pty_linux.go
+++ b/pty_linux.go
@@ -49,6 +49,6 @@ func ptsname(f *os.File) (string, error) {
 
 func unlockpt(f *os.File) error {
 	var u _C_int
-	// use TIOCSPTLCK with a pointer to zero to clear the lock
+	// use TIOCSPTLCK with a pointer to zero to clear the lock.
 	return ioctl(f, syscall.TIOCSPTLCK, uintptr(unsafe.Pointer(&u))) //nolint:gosec // Expected unsafe pointer for Syscall call.
 }
diff --git a/winsize.go b/winsize.go
index 57323f4..cfa3e5f 100644
--- a/winsize.go
+++ b/winsize.go
@@ -10,10 +10,7 @@ func InheritSize(pty, tty *os.File) error {
 	if err != nil {
 		return err
 	}
-	if err := Setsize(tty, size); err != nil {
-		return err
-	}
-	return nil
+	return Setsize(tty, size)
 }
 
 // Getsize returns the number of rows (lines) and cols (positions
diff --git a/winsize_unix.go b/winsize_unix.go
index ad98c8a..8dbbcda 100644
--- a/winsize_unix.go
+++ b/winsize_unix.go
@@ -11,10 +11,10 @@ import (
 
 // Winsize describes the terminal size.
 type Winsize struct {
-	Rows uint16 // ws_row: Number of rows (in cells)
-	Cols uint16 // ws_col: Number of columns (in cells)
-	X    uint16 // ws_xpixel: Width in pixels
-	Y    uint16 // ws_ypixel: Height in pixels
+	Rows uint16 // ws_row: Number of rows (in cells).
+	Cols uint16 // ws_col: Number of columns (in cells).
+	X    uint16 // ws_xpixel: Width in pixels.
+	Y    uint16 // ws_ypixel: Height in pixels.
 }
 
 // Setsize resizes t to s.

From 0a15590bf0148e86be03cc00016045cf42e6ee0e Mon Sep 17 00:00:00 2001
From: "Guillaume J. Charmes" <git+guillaume@charmes.net>
Date: Tue, 31 Oct 2023 10:55:31 -0400
Subject: [PATCH 4/5] Skip tests for go1.6.

---
 .github/workflows/test.yml | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index dab2c73..4a949d3 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -48,5 +48,8 @@ jobs:
       - name: Build
         run: go build -v
 
-      - name: Test
+      # Skip tests for 1.6 as we use modern Go.
+      # If the main lib builds and tests pass on other versions, we are good.
+      - if: ${{ matrix.go_version != '1.6.x' }}
+        name: Test
         run: go test -v

From cafb3b47d008d5dd887a8f266969e15f3fe6a439 Mon Sep 17 00:00:00 2001
From: "Guillaume J. Charmes" <git+guillaume@charmes.net>
Date: Tue, 31 Oct 2023 14:32:20 -0400
Subject: [PATCH 5/5] Fix typo.

---
 io_test.go | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/io_test.go b/io_test.go
index d448eb7..a429edb 100644
--- a/io_test.go
+++ b/io_test.go
@@ -18,7 +18,7 @@ const (
 	timeout        = time.Second
 )
 
-//nolint:gochecknoglobals // Expected global lock to avodi potential race on (*os.File).Fd().
+//nolint:gochecknoglobals // Expected global lock to avoid potential race on (*os.File).Fd().
 var glTestFdLock sync.Mutex
 
 // Check that SetDeadline() works for ptmx.