From 0b2cabbc31ca09d696f6472b3d137fb60858062a Mon Sep 17 00:00:00 2001
From: Jakob Borg <jakob@kastelo.net>
Date: Sat, 2 Feb 2019 11:45:17 +0100
Subject: [PATCH] all: Even more boring linter fixes (#5501)

---
 lib/osutil/atomic.go                   |  4 +-
 lib/osutil/osutil.go                   |  8 ++--
 lib/osutil/osutil_test.go              | 52 +++++++++++++-------------
 lib/osutil/traversessymlink_test.go    |  6 +--
 lib/protocol/benchmark_test.go         |  4 +-
 lib/protocol/deviceid.go               |  2 +-
 lib/protocol/deviceid_test.go          |  8 +++-
 lib/protocol/hello_test.go             |  3 --
 lib/protocol/protocol.go               | 10 ++---
 lib/protocol/protocol_test.go          |  8 ++--
 lib/rand/random.go                     |  2 +-
 lib/rc/rc.go                           |  2 +-
 lib/relay/client/methods.go            |  6 +--
 lib/scanner/blocks.go                  |  2 +-
 lib/scanner/blocks_test.go             | 10 ++---
 lib/scanner/walk.go                    |  8 ++--
 lib/scanner/walk_test.go               | 10 ++---
 lib/sha256/sha256.go                   |  6 +--
 lib/sync/debug.go                      |  2 +-
 lib/tlsutil/tlsutil.go                 |  6 +--
 lib/upgrade/upgrade_supported.go       |  4 +-
 lib/versioner/simple.go                |  4 +-
 lib/versioner/staggered.go             |  4 +-
 lib/versioner/staggered_test.go        |  2 +-
 lib/versioner/trashcan.go              |  6 +--
 lib/versioner/trashcan_test.go         |  2 +-
 lib/watchaggregator/aggregator_test.go | 48 +++++++++++++++++++-----
 lib/weakhash/benchmark_test.go         |  6 +--
 28 files changed, 131 insertions(+), 104 deletions(-)

diff --git a/lib/osutil/atomic.go b/lib/osutil/atomic.go
index 9618b724c..eca4ea67a 100644
--- a/lib/osutil/atomic.go
+++ b/lib/osutil/atomic.go
@@ -81,7 +81,7 @@ func (w *AtomicWriter) Close() error {
 	}
 
 	// Try to not leave temp file around, but ignore error.
-	defer w.fs.Remove(w.next.Name())
+	defer func() { _ = w.fs.Remove(w.next.Name()) }()
 
 	if err := w.next.Sync(); err != nil {
 		w.err = err
@@ -110,7 +110,7 @@ func (w *AtomicWriter) Close() error {
 
 	// fsync the directory too
 	if fd, err := w.fs.Open(filepath.Dir(w.next.Name())); err == nil {
-		fd.Sync()
+		_ = fd.Sync()
 		fd.Close()
 	}
 
diff --git a/lib/osutil/osutil.go b/lib/osutil/osutil.go
index 256ca1dab..478b238b8 100644
--- a/lib/osutil/osutil.go
+++ b/lib/osutil/osutil.go
@@ -42,7 +42,7 @@ func TryRename(filesystem fs.Filesystem, from, to string) error {
 func Rename(filesystem fs.Filesystem, from, to string) error {
 	// Don't leave a dangling temp file in case of rename error
 	if !(runtime.GOOS == "windows" && strings.EqualFold(from, to)) {
-		defer filesystem.Remove(from)
+		defer func() { _ = filesystem.Remove(from) }()
 	}
 	return TryRename(filesystem, from, to)
 }
@@ -94,13 +94,13 @@ func withPreparedTarget(filesystem fs.Filesystem, from, to string, f func() erro
 	// Make sure the destination directory is writeable
 	toDir := filepath.Dir(to)
 	if info, err := filesystem.Stat(toDir); err == nil && info.IsDir() && info.Mode()&0200 == 0 {
-		filesystem.Chmod(toDir, 0755)
-		defer filesystem.Chmod(toDir, info.Mode())
+		_ = filesystem.Chmod(toDir, 0755)
+		defer func() { _ = filesystem.Chmod(toDir, info.Mode()) }()
 	}
 
 	// On Windows, make sure the destination file is writeable (or we can't delete it)
 	if runtime.GOOS == "windows" {
-		filesystem.Chmod(to, 0666)
+		_ = filesystem.Chmod(to, 0666)
 		if !strings.EqualFold(from, to) {
 			err := filesystem.Remove(to)
 			if err != nil && !fs.IsNotExist(err) {
diff --git a/lib/osutil/osutil_test.go b/lib/osutil/osutil_test.go
index c6ee2d487..80f8ce7b7 100644
--- a/lib/osutil/osutil_test.go
+++ b/lib/osutil/osutil_test.go
@@ -26,9 +26,9 @@ func TestInWriteableDir(t *testing.T) {
 
 	fs := fs.NewFilesystem(fs.FilesystemTypeBasic, ".")
 
-	os.Mkdir("testdata", 0700)
-	os.Mkdir("testdata/rw", 0700)
-	os.Mkdir("testdata/ro", 0500)
+	_ = os.Mkdir("testdata", 0700)
+	_ = os.Mkdir("testdata/rw", 0700)
+	_ = os.Mkdir("testdata/ro", 0500)
 
 	create := func(name string) error {
 		fd, err := os.Create(name)
@@ -87,7 +87,7 @@ func TestInWritableDirWindowsRemove(t *testing.T) {
 	if err != nil {
 		t.Fatal(err)
 	}
-	defer os.Chmod("testdata/windows/ro/readonlynew", 0700)
+	defer func() { _ = os.Chmod("testdata/windows/ro/readonlynew", 0700) }()
 	defer os.RemoveAll("testdata")
 
 	create := func(name string) error {
@@ -99,12 +99,12 @@ func TestInWritableDirWindowsRemove(t *testing.T) {
 		return nil
 	}
 
-	os.Mkdir("testdata", 0700)
+	_ = os.Mkdir("testdata", 0700)
 
-	os.Mkdir("testdata/windows", 0500)
-	os.Mkdir("testdata/windows/ro", 0500)
-	create("testdata/windows/ro/readonly")
-	os.Chmod("testdata/windows/ro/readonly", 0500)
+	_ = os.Mkdir("testdata/windows", 0500)
+	_ = os.Mkdir("testdata/windows/ro", 0500)
+	_ = create("testdata/windows/ro/readonly")
+	_ = os.Chmod("testdata/windows/ro/readonly", 0500)
 
 	fs := fs.NewFilesystem(fs.FilesystemTypeBasic, ".")
 
@@ -128,8 +128,8 @@ func TestInWritableDirWindowsRemoveAll(t *testing.T) {
 	if err != nil {
 		t.Fatal(err)
 	}
-	defer os.Chmod("testdata/windows/ro/readonlynew", 0700)
-	defer os.RemoveAll("testdata")
+	defer func() { _ = os.Chmod("testdata/windows/ro/readonlynew", 0700) }()
+	defer func() { _ = os.RemoveAll("testdata") }()
 
 	create := func(name string) error {
 		fd, err := os.Create(name)
@@ -140,12 +140,12 @@ func TestInWritableDirWindowsRemoveAll(t *testing.T) {
 		return nil
 	}
 
-	os.Mkdir("testdata", 0700)
+	_ = os.Mkdir("testdata", 0700)
 
-	os.Mkdir("testdata/windows", 0500)
-	os.Mkdir("testdata/windows/ro", 0500)
-	create("testdata/windows/ro/readonly")
-	os.Chmod("testdata/windows/ro/readonly", 0500)
+	_ = os.Mkdir("testdata/windows", 0500)
+	_ = os.Mkdir("testdata/windows/ro", 0500)
+	_ = create("testdata/windows/ro/readonly")
+	_ = os.Chmod("testdata/windows/ro/readonly", 0500)
 
 	if err := os.RemoveAll("testdata/windows"); err != nil {
 		t.Errorf("Unexpected error: %s", err)
@@ -162,8 +162,8 @@ func TestInWritableDirWindowsRename(t *testing.T) {
 	if err != nil {
 		t.Fatal(err)
 	}
-	defer os.Chmod("testdata/windows/ro/readonlynew", 0700)
-	defer os.RemoveAll("testdata")
+	defer func() { _ = os.Chmod("testdata/windows/ro/readonlynew", 0700) }()
+	defer func() { _ = os.RemoveAll("testdata") }()
 
 	create := func(name string) error {
 		fd, err := os.Create(name)
@@ -174,12 +174,12 @@ func TestInWritableDirWindowsRename(t *testing.T) {
 		return nil
 	}
 
-	os.Mkdir("testdata", 0700)
+	_ = os.Mkdir("testdata", 0700)
 
-	os.Mkdir("testdata/windows", 0500)
-	os.Mkdir("testdata/windows/ro", 0500)
-	create("testdata/windows/ro/readonly")
-	os.Chmod("testdata/windows/ro/readonly", 0500)
+	_ = os.Mkdir("testdata/windows", 0500)
+	_ = os.Mkdir("testdata/windows/ro", 0500)
+	_ = create("testdata/windows/ro/readonly")
+	_ = os.Chmod("testdata/windows/ro/readonly", 0500)
 
 	fs := fs.NewFilesystem(fs.FilesystemTypeBasic, ".")
 
@@ -232,7 +232,7 @@ func TestIsDeleted(t *testing.T) {
 
 	testFs := fs.NewFilesystem(fs.FilesystemTypeBasic, "testdata")
 
-	testFs.MkdirAll("dir", 0777)
+	_ = testFs.MkdirAll("dir", 0777)
 	for _, f := range []string{"file", "del.file", "dir.file", "dir/file"} {
 		fd, err := testFs.Create(f)
 		if err != nil {
@@ -242,7 +242,7 @@ func TestIsDeleted(t *testing.T) {
 	}
 	if runtime.GOOS != "windows" {
 		// Can't create unreadable dir on windows
-		testFs.MkdirAll("inacc", 0777)
+		_ = testFs.MkdirAll("inacc", 0777)
 		if err := testFs.Chmod("inacc", 0000); err == nil {
 			if _, err := testFs.Lstat("inacc/file"); fs.IsPermission(err) {
 				// May fail e.g. if tests are run as root -> just skip
@@ -265,6 +265,6 @@ func TestIsDeleted(t *testing.T) {
 		}
 	}
 
-	testFs.Chmod("inacc", 0777)
+	_ = testFs.Chmod("inacc", 0777)
 	os.RemoveAll("testdata")
 }
diff --git a/lib/osutil/traversessymlink_test.go b/lib/osutil/traversessymlink_test.go
index b69affaac..a8228a5d2 100644
--- a/lib/osutil/traversessymlink_test.go
+++ b/lib/osutil/traversessymlink_test.go
@@ -25,7 +25,7 @@ func TestTraversesSymlink(t *testing.T) {
 	defer os.RemoveAll(tmpDir)
 
 	fs := fs.NewFilesystem(fs.FilesystemTypeBasic, tmpDir)
-	fs.MkdirAll("a/b/c", 0755)
+	_ = fs.MkdirAll("a/b/c", 0755)
 	if err = osutil.DebugSymlinkForTestsOnly(filepath.Join(fs.URI(), "a", "b"), filepath.Join(fs.URI(), "a", "l")); err != nil {
 		if runtime.GOOS == "windows" {
 			t.Skip("Symlinks aren't working")
@@ -78,7 +78,7 @@ func TestIssue4875(t *testing.T) {
 	defer os.RemoveAll(tmpDir)
 
 	testFs := fs.NewFilesystem(fs.FilesystemTypeBasic, tmpDir)
-	testFs.MkdirAll("a/b/c", 0755)
+	_ = testFs.MkdirAll("a/b/c", 0755)
 	if err = osutil.DebugSymlinkForTestsOnly(filepath.Join(testFs.URI(), "a", "b"), filepath.Join(testFs.URI(), "a", "l")); err != nil {
 		if runtime.GOOS == "windows" {
 			t.Skip("Symlinks aren't working")
@@ -107,7 +107,7 @@ func BenchmarkTraversesSymlink(b *testing.B) {
 	os.RemoveAll("testdata")
 	defer os.RemoveAll("testdata")
 	fs := fs.NewFilesystem(fs.FilesystemTypeBasic, "testdata")
-	fs.MkdirAll("a/b/c", 0755)
+	_ = fs.MkdirAll("a/b/c", 0755)
 
 	for i := 0; i < b.N; i++ {
 		traversesSymlinkResult = osutil.TraversesSymlink(fs, "a/b/c")
diff --git a/lib/protocol/benchmark_test.go b/lib/protocol/benchmark_test.go
index 308d7cc13..99b68bf1e 100644
--- a/lib/protocol/benchmark_test.go
+++ b/lib/protocol/benchmark_test.go
@@ -132,8 +132,8 @@ func getTCPConnectionPair() (net.Conn, net.Conn, error) {
 	}
 
 	// Set the buffer sizes etc as usual
-	dialer.SetTCPOptions(conn0)
-	dialer.SetTCPOptions(conn1)
+	_ = dialer.SetTCPOptions(conn0)
+	_ = dialer.SetTCPOptions(conn1)
 
 	return conn0, conn1, nil
 }
diff --git a/lib/protocol/deviceid.go b/lib/protocol/deviceid.go
index 015080387..704fe327e 100644
--- a/lib/protocol/deviceid.go
+++ b/lib/protocol/deviceid.go
@@ -35,7 +35,7 @@ func repeatedDeviceID(v byte) (d DeviceID) {
 func NewDeviceID(rawCert []byte) DeviceID {
 	var n DeviceID
 	hf := sha256.New()
-	hf.Write(rawCert)
+	_, _ = hf.Write(rawCert)
 	hf.Sum(n[:0])
 	return n
 }
diff --git a/lib/protocol/deviceid_test.go b/lib/protocol/deviceid_test.go
index 45f930e90..d7c05313a 100644
--- a/lib/protocol/deviceid_test.go
+++ b/lib/protocol/deviceid_test.go
@@ -64,9 +64,13 @@ func TestMarshallingDeviceID(t *testing.T) {
 	n2 := DeviceID{}
 
 	bs, _ := n0.MarshalText()
-	n1.UnmarshalText(bs)
+	if err := n1.UnmarshalText(bs); err != nil {
+		t.Fatal(err)
+	}
 	bs, _ = n1.MarshalText()
-	n2.UnmarshalText(bs)
+	if err := n2.UnmarshalText(bs); err != nil {
+		t.Fatal(err)
+	}
 
 	if n2.String() != n0.String() {
 		t.Errorf("String marshalling error; %q != %q", n2.String(), n0.String())
diff --git a/lib/protocol/hello_test.go b/lib/protocol/hello_test.go
index 4ef5d9933..6576a639e 100644
--- a/lib/protocol/hello_test.go
+++ b/lib/protocol/hello_test.go
@@ -7,12 +7,9 @@ import (
 	"encoding/binary"
 	"encoding/hex"
 	"io"
-	"regexp"
 	"testing"
 )
 
-var spaceRe = regexp.MustCompile(`\s`)
-
 func TestVersion14Hello(t *testing.T) {
 	// Tests that we can send and receive a version 0.14 hello message.
 
diff --git a/lib/protocol/protocol.go b/lib/protocol/protocol.go
index 7d9628e25..b2fa0fa7a 100644
--- a/lib/protocol/protocol.go
+++ b/lib/protocol/protocol.go
@@ -175,7 +175,6 @@ type rawConnection struct {
 	closed        chan struct{}
 	closeOnce     sync.Once
 	sendCloseOnce sync.Once
-	writerExited  chan struct{}
 	compression   Compression
 }
 
@@ -227,7 +226,10 @@ func NewConnection(deviceID DeviceID, reader io.Reader, writer io.Writer, receiv
 // Start creates the goroutines for sending and receiving of messages. It must
 // be called exactly once after creating a connection.
 func (c *rawConnection) Start() {
-	go c.readerLoop()
+	go func() {
+		err := c.readerLoop()
+		c.internalClose(err)
+	}()
 	go c.writerLoop()
 	go c.pingSender()
 	go c.pingReceiver()
@@ -336,10 +338,6 @@ func (c *rawConnection) ping() bool {
 }
 
 func (c *rawConnection) readerLoop() (err error) {
-	defer func() {
-		c.internalClose(err)
-	}()
-
 	fourByteBuf := make([]byte, 4)
 	state := stateInitial
 	for {
diff --git a/lib/protocol/protocol_test.go b/lib/protocol/protocol_test.go
index b567b6270..edbd5cbb8 100644
--- a/lib/protocol/protocol_test.go
+++ b/lib/protocol/protocol_test.go
@@ -69,8 +69,8 @@ func TestClose(t *testing.T) {
 		t.Error("Ping should not return true")
 	}
 
-	c0.Index("default", nil)
-	c0.Index("default", nil)
+	_ = c0.Index("default", nil)
+	_ = c0.Index("default", nil)
 
 	if _, err := c0.Request("default", "foo", 0, 0, nil, 0, false); err == nil {
 		t.Error("Request should return an error")
@@ -225,8 +225,8 @@ func testMarshal(t *testing.T, prefix string, m1, m2 message) bool {
 	bs1, _ := json.MarshalIndent(m1, "", "  ")
 	bs2, _ := json.MarshalIndent(m2, "", "  ")
 	if !bytes.Equal(bs1, bs2) {
-		ioutil.WriteFile(prefix+"-1.txt", bs1, 0644)
-		ioutil.WriteFile(prefix+"-2.txt", bs2, 0644)
+		_ = ioutil.WriteFile(prefix+"-1.txt", bs1, 0644)
+		_ = ioutil.WriteFile(prefix+"-2.txt", bs2, 0644)
 		return false
 	}
 
diff --git a/lib/rand/random.go b/lib/rand/random.go
index 23a2f255e..689ea3c4a 100644
--- a/lib/rand/random.go
+++ b/lib/rand/random.go
@@ -67,7 +67,7 @@ func Intn(n int) int {
 // suitable for use a predictable random seed.
 func SeedFromBytes(bs []byte) int64 {
 	h := md5.New()
-	h.Write(bs)
+	_, _ = h.Write(bs)
 	s := h.Sum(nil)
 	// The MD5 hash of the byte slice is 16 bytes long. We interpret it as two
 	// uint64s and XOR them together.
diff --git a/lib/rc/rc.go b/lib/rc/rc.go
index 21004fef5..327a435c9 100644
--- a/lib/rc/rc.go
+++ b/lib/rc/rc.go
@@ -114,7 +114,7 @@ func (p *Process) Start(bin string, args ...string) error {
 }
 
 func (p *Process) wait() {
-	p.cmd.Wait()
+	_ = p.cmd.Wait()
 
 	if p.logfd != nil {
 		p.stopErr = p.checkForProblems(p.logfd)
diff --git a/lib/relay/client/methods.go b/lib/relay/client/methods.go
index 6e4f1213e..299f78223 100644
--- a/lib/relay/client/methods.go
+++ b/lib/relay/client/methods.go
@@ -27,7 +27,7 @@ func GetInvitationFromRelay(uri *url.URL, id syncthingprotocol.DeviceID, certs [
 	}
 
 	conn := tls.Client(rconn, configForCerts(certs))
-	conn.SetDeadline(time.Now().Add(timeout))
+	_ = conn.SetDeadline(time.Now().Add(timeout))
 
 	if err := performHandshakeAndValidation(conn, uri); err != nil {
 		return protocol.SessionInvitation{}, err
@@ -75,7 +75,7 @@ func JoinSession(invitation protocol.SessionInvitation) (net.Conn, error) {
 		Key: invitation.Key,
 	}
 
-	conn.SetDeadline(time.Now().Add(10 * time.Second))
+	_ = conn.SetDeadline(time.Now().Add(10 * time.Second))
 	err = protocol.WriteMessage(conn, request)
 	if err != nil {
 		return nil, err
@@ -86,7 +86,7 @@ func JoinSession(invitation protocol.SessionInvitation) (net.Conn, error) {
 		return nil, err
 	}
 
-	conn.SetDeadline(time.Time{})
+	_ = conn.SetDeadline(time.Time{})
 
 	switch msg := message.(type) {
 	case protocol.Response:
diff --git a/lib/scanner/blocks.go b/lib/scanner/blocks.go
index 3d3e641ec..477dfff0e 100644
--- a/lib/scanner/blocks.go
+++ b/lib/scanner/blocks.go
@@ -116,7 +116,7 @@ func Validate(buf, hash []byte, weakHash uint32) bool {
 			return true
 		}
 		// Copy error or mismatch, go to next algo.
-		rd.Seek(0, io.SeekStart)
+		_, _ = rd.Seek(0, io.SeekStart)
 	}
 
 	if len(hash) > 0 {
diff --git a/lib/scanner/blocks_test.go b/lib/scanner/blocks_test.go
index 99f1a7164..12c64bbd2 100644
--- a/lib/scanner/blocks_test.go
+++ b/lib/scanner/blocks_test.go
@@ -112,10 +112,10 @@ func TestAdler32Variants(t *testing.T) {
 	hf2 := rollingAdler32.New()
 
 	checkFn := func(data []byte) bool {
-		hf1.Write(data)
+		_, _ = hf1.Write(data)
 		sum1 := hf1.Sum32()
 
-		hf2.Write(data)
+		_, _ = hf2.Write(data)
 		sum2 := hf2.Sum32()
 
 		hf1.Reset()
@@ -127,7 +127,7 @@ func TestAdler32Variants(t *testing.T) {
 	// protocol block sized data
 	data := make([]byte, protocol.MinBlockSize)
 	for i := 0; i < 5; i++ {
-		rand.Read(data)
+		_, _ = rand.Read(data)
 		if !checkFn(data) {
 			t.Errorf("Hash mismatch on block sized data")
 		}
@@ -145,13 +145,13 @@ func TestAdler32Variants(t *testing.T) {
 	windowSize := 128
 
 	hf3 := rollingAdler32.New()
-	hf3.Write(data[:windowSize])
+	_, _ = hf3.Write(data[:windowSize])
 
 	for i := windowSize; i < len(data); i++ {
 		if i%windowSize == 0 {
 			// let the reference function catch up
 			hf2.Reset()
-			hf2.Write(data[i-windowSize : i])
+			_, _ = hf2.Write(data[i-windowSize : i])
 
 			// verify that they are in sync with the rolling function
 			sum2 := hf2.Sum32()
diff --git a/lib/scanner/walk.go b/lib/scanner/walk.go
index 5f76a848e..6dabf1b46 100644
--- a/lib/scanner/walk.go
+++ b/lib/scanner/walk.go
@@ -17,7 +17,7 @@ import (
 	"time"
 	"unicode/utf8"
 
-	"github.com/rcrowley/go-metrics"
+	metrics "github.com/rcrowley/go-metrics"
 	"github.com/syncthing/syncthing/lib/events"
 	"github.com/syncthing/syncthing/lib/fs"
 	"github.com/syncthing/syncthing/lib/ignore"
@@ -108,10 +108,10 @@ func (w *walker) walk(ctx context.Context) chan ScanResult {
 	go func() {
 		hashFiles := w.walkAndHashFiles(ctx, toHashChan, finishedChan)
 		if len(w.Subs) == 0 {
-			w.Filesystem.Walk(".", hashFiles)
+			_ = w.Filesystem.Walk(".", hashFiles)
 		} else {
 			for _, sub := range w.Subs {
-				w.Filesystem.Walk(sub, hashFiles)
+				_ = w.Filesystem.Walk(sub, hashFiles)
 			}
 		}
 		close(toHashChan)
@@ -223,7 +223,7 @@ func (w *walker) walkAndHashFiles(ctx context.Context, toHashChan chan<- protoco
 		if fs.IsTemporary(path) {
 			l.Debugln("temporary:", path, "err:", err)
 			if err == nil && info.IsRegular() && info.ModTime().Add(w.TempLifetime).Before(now) {
-				w.Filesystem.Remove(path)
+				_ = w.Filesystem.Remove(path)
 				l.Debugln("removing temporary:", path, info.ModTime())
 			}
 			return nil
diff --git a/lib/scanner/walk_test.go b/lib/scanner/walk_test.go
index 74725a51b..0b1766722 100644
--- a/lib/scanner/walk_test.go
+++ b/lib/scanner/walk_test.go
@@ -216,7 +216,7 @@ func TestNormalization(t *testing.T) {
 			if fd, err := testFs.OpenFile(filepath.Join("normalization", s1, s2), os.O_CREATE|os.O_EXCL, 0644); err != nil {
 				t.Fatal(err)
 			} else {
-				fd.Write([]byte("test"))
+				_, _ = fd.Write([]byte("test"))
 				fd.Close()
 			}
 		}
@@ -257,7 +257,7 @@ func TestIssue1507(t *testing.T) {
 	f := make(chan ScanResult, 100)
 	fn := w.walkAndHashFiles(context.TODO(), h, f)
 
-	fn("", nil, protocol.ErrClosed)
+	_ = fn("", nil, protocol.ErrClosed)
 }
 
 func TestWalkSymlinkUnix(t *testing.T) {
@@ -268,9 +268,9 @@ func TestWalkSymlinkUnix(t *testing.T) {
 
 	// Create a folder with a symlink in it
 	os.RemoveAll("_symlinks")
-	os.Mkdir("_symlinks", 0755)
+	_ = os.Mkdir("_symlinks", 0755)
 	defer os.RemoveAll("_symlinks")
-	os.Symlink("../testdata", "_symlinks/link")
+	_ = os.Symlink("../testdata", "_symlinks/link")
 
 	fs := fs.NewFilesystem(fs.FilesystemTypeBasic, "_symlinks")
 	for _, path := range []string{".", "link"} {
@@ -298,7 +298,7 @@ func TestWalkSymlinkWindows(t *testing.T) {
 	// Create a folder with a symlink in it
 	name := "_symlinks-win"
 	os.RemoveAll(name)
-	os.Mkdir(name, 0755)
+	_ = os.Mkdir(name, 0755)
 	defer os.RemoveAll(name)
 	fs := fs.NewFilesystem(fs.FilesystemTypeBasic, name)
 	if err := osutil.DebugSymlinkForTestsOnly("../testdata", "_symlinks/link"); err != nil {
diff --git a/lib/sha256/sha256.go b/lib/sha256/sha256.go
index c301f4542..e9188a4fc 100644
--- a/lib/sha256/sha256.go
+++ b/lib/sha256/sha256.go
@@ -115,12 +115,12 @@ func cpuBenchOnce(duration time.Duration, newFn func() hash.Hash) float64 {
 	chunkSize := 100 * 1 << 10
 	h := newFn()
 	bs := make([]byte, chunkSize)
-	rand.Reader.Read(bs)
+	_, _ = rand.Reader.Read(bs)
 
 	t0 := time.Now()
 	b := 0
 	for time.Since(t0) < duration {
-		h.Write(bs)
+		_, _ = h.Write(bs)
 		b += chunkSize
 	}
 	h.Sum(nil)
@@ -146,7 +146,7 @@ func verifyCorrectness() {
 	input := "Syncthing Magic Testing Value\n"
 
 	h := New()
-	h.Write([]byte(input))
+	_, _ = h.Write([]byte(input))
 	sum := hex.EncodeToString(h.Sum(nil))
 	if sum != correct {
 		panic("sha256 is broken")
diff --git a/lib/sync/debug.go b/lib/sync/debug.go
index 5c4a23609..5ba6c64ff 100644
--- a/lib/sync/debug.go
+++ b/lib/sync/debug.go
@@ -12,7 +12,7 @@ import (
 	"strings"
 	"time"
 
-	"github.com/sasha-s/go-deadlock"
+	deadlock "github.com/sasha-s/go-deadlock"
 	"github.com/syncthing/syncthing/lib/logger"
 )
 
diff --git a/lib/tlsutil/tlsutil.go b/lib/tlsutil/tlsutil.go
index 8b8014f8a..c8c11fc0d 100644
--- a/lib/tlsutil/tlsutil.go
+++ b/lib/tlsutil/tlsutil.go
@@ -186,9 +186,9 @@ func (l *DowngradingListener) AcceptNoWrapTLS() (net.Conn, bool, error) {
 	}
 
 	var first [1]byte
-	conn.SetReadDeadline(time.Now().Add(1 * time.Second))
+	_ = conn.SetReadDeadline(time.Now().Add(1 * time.Second))
 	n, err := conn.Read(first[:])
-	conn.SetReadDeadline(time.Time{})
+	_ = conn.SetReadDeadline(time.Time{})
 	if err != nil || n == 0 {
 		// We hit a read error here, but the Accept() call succeeded so we must not return an error.
 		// We return the connection as is with a special error which handles this
@@ -308,7 +308,7 @@ JpJcUNtrf1XK49IlpWW1Ds8seQsSg7/9BQ==
 
 	c := tls.Client(c0, clientCfg)
 	go func() {
-		c.Handshake()
+		_ = c.Handshake()
 	}()
 
 	s := tls.Server(c1, serverCfg)
diff --git a/lib/upgrade/upgrade_supported.go b/lib/upgrade/upgrade_supported.go
index 163b9a336..3d862d914 100644
--- a/lib/upgrade/upgrade_supported.go
+++ b/lib/upgrade/upgrade_supported.go
@@ -201,8 +201,8 @@ func upgradeToURL(archiveName, binary string, url string) error {
 	if err != nil {
 		return err
 	}
-	if os.Rename(fname, binary); err != nil {
-		os.Rename(old, binary)
+	if err := os.Rename(fname, binary); err != nil {
+		_ = os.Rename(old, binary)
 		return err
 	}
 	return nil
diff --git a/lib/versioner/simple.go b/lib/versioner/simple.go
index 79dad81c5..ac1611d48 100644
--- a/lib/versioner/simple.go
+++ b/lib/versioner/simple.go
@@ -59,8 +59,8 @@ func (v Simple) Archive(filePath string) error {
 	if err != nil {
 		if fs.IsNotExist(err) {
 			l.Debugln("creating versions dir .stversions")
-			v.fs.Mkdir(versionsDir, 0755)
-			v.fs.Hide(versionsDir)
+			_ = v.fs.Mkdir(versionsDir, 0755)
+			_ = v.fs.Hide(versionsDir)
 		} else {
 			return err
 		}
diff --git a/lib/versioner/staggered.go b/lib/versioner/staggered.go
index beea0aa67..639c9119a 100644
--- a/lib/versioner/staggered.go
+++ b/lib/versioner/staggered.go
@@ -239,8 +239,8 @@ func (v *Staggered) Archive(filePath string) error {
 	if _, err := v.versionsFs.Stat("."); err != nil {
 		if fs.IsNotExist(err) {
 			l.Debugln("creating versions dir", v.versionsFs)
-			v.versionsFs.MkdirAll(".", 0755)
-			v.versionsFs.Hide(".")
+			_ = v.versionsFs.MkdirAll(".", 0755)
+			_ = v.versionsFs.Hide(".")
 		} else {
 			return err
 		}
diff --git a/lib/versioner/staggered_test.go b/lib/versioner/staggered_test.go
index cd84c069f..b405b261c 100644
--- a/lib/versioner/staggered_test.go
+++ b/lib/versioner/staggered_test.go
@@ -60,7 +60,7 @@ func TestStaggeredVersioningVersionCount(t *testing.T) {
 	}
 	sort.Strings(delete)
 
-	os.MkdirAll("testdata/.stversions", 0755)
+	_ = os.MkdirAll("testdata/.stversions", 0755)
 	defer os.RemoveAll("testdata")
 
 	v := NewStaggered("", fs.NewFilesystem(fs.FilesystemTypeBasic, "testdata"), map[string]string{"maxAge": strconv.Itoa(365 * 86400)}).(*Staggered)
diff --git a/lib/versioner/trashcan.go b/lib/versioner/trashcan.go
index 70e65ac83..5f2379c58 100644
--- a/lib/versioner/trashcan.go
+++ b/lib/versioner/trashcan.go
@@ -65,7 +65,7 @@ func (t *Trashcan) Archive(filePath string) error {
 		if err := t.fs.MkdirAll(versionsDir, 0777); err != nil {
 			return err
 		}
-		t.fs.Hide(versionsDir)
+		_ = t.fs.Hide(versionsDir)
 	}
 
 	l.Debugln("archiving", filePath)
@@ -84,7 +84,7 @@ func (t *Trashcan) Archive(filePath string) error {
 	// Set the mtime to the time the file was deleted. This is used by the
 	// cleanout routine. If this fails things won't work optimally but there's
 	// not much we can do about it so we ignore the error.
-	t.fs.Chtimes(archivedPath, time.Now(), time.Now())
+	_ = t.fs.Chtimes(archivedPath, time.Now(), time.Now())
 
 	return nil
 }
@@ -144,7 +144,7 @@ func (t *Trashcan) cleanoutArchive() error {
 
 		if info.ModTime().Before(cutoff) {
 			// The file is too old; remove it.
-			t.fs.Remove(path)
+			_ = t.fs.Remove(path)
 		} else {
 			// Keep this file, and remember it so we don't unnecessarily try
 			// to remove this directory.
diff --git a/lib/versioner/trashcan_test.go b/lib/versioner/trashcan_test.go
index 023e5806b..e7f5b122b 100644
--- a/lib/versioner/trashcan_test.go
+++ b/lib/versioner/trashcan_test.go
@@ -42,7 +42,7 @@ func TestTrashcanCleanout(t *testing.T) {
 
 	oldTime := time.Now().Add(-8 * 24 * time.Hour)
 	for _, tc := range testcases {
-		os.MkdirAll(filepath.Dir(tc.file), 0777)
+		_ = os.MkdirAll(filepath.Dir(tc.file), 0777)
 		if err := ioutil.WriteFile(tc.file, []byte("data"), 0644); err != nil {
 			t.Fatal(err)
 		}
diff --git a/lib/watchaggregator/aggregator_test.go b/lib/watchaggregator/aggregator_test.go
index 25483781a..5815cbfbc 100644
--- a/lib/watchaggregator/aggregator_test.go
+++ b/lib/watchaggregator/aggregator_test.go
@@ -65,46 +65,71 @@ func TestAggregate(t *testing.T) {
 
 	folderCfg := defaultFolderCfg.Copy()
 	folderCfg.ID = "Aggregate"
-	ctx, _ := context.WithCancel(context.Background())
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
 	a := newAggregator(folderCfg, ctx)
 
 	// checks whether maxFilesPerDir events in one dir are kept as is
 	for i := 0; i < maxFilesPerDir; i++ {
-		a.newEvent(fs.Event{filepath.Join("parent", strconv.Itoa(i)), fs.NonRemove}, inProgress)
+		a.newEvent(fs.Event{
+			Name: filepath.Join("parent", strconv.Itoa(i)),
+			Type: fs.NonRemove,
+		}, inProgress)
 	}
 	if l := len(getEventPaths(a.root, ".", a)); l != maxFilesPerDir {
 		t.Errorf("Unexpected number of events stored, got %v, expected %v", l, maxFilesPerDir)
 	}
 
 	// checks whether maxFilesPerDir+1 events in one dir are aggregated to parent dir
-	a.newEvent(fs.Event{filepath.Join("parent", "new"), fs.NonRemove}, inProgress)
+	a.newEvent(fs.Event{
+		Name: filepath.Join("parent", "new"),
+		Type: fs.NonRemove,
+	}, inProgress)
 	compareBatchToExpectedDirect(t, getEventPaths(a.root, ".", a), []string{"parent"})
 
 	// checks that adding an event below "parent" does not change anything
-	a.newEvent(fs.Event{filepath.Join("parent", "extra"), fs.NonRemove}, inProgress)
+	a.newEvent(fs.Event{
+		Name: filepath.Join("parent", "extra"),
+		Type: fs.NonRemove,
+	}, inProgress)
 	compareBatchToExpectedDirect(t, getEventPaths(a.root, ".", a), []string{"parent"})
 
 	// again test aggregation in "parent" but with event in subdirs
 	a = newAggregator(folderCfg, ctx)
 	for i := 0; i < maxFilesPerDir; i++ {
-		a.newEvent(fs.Event{filepath.Join("parent", strconv.Itoa(i)), fs.NonRemove}, inProgress)
+		a.newEvent(fs.Event{
+			Name: filepath.Join("parent", strconv.Itoa(i)),
+			Type: fs.NonRemove,
+		}, inProgress)
 	}
-	a.newEvent(fs.Event{filepath.Join("parent", "sub", "new"), fs.NonRemove}, inProgress)
+	a.newEvent(fs.Event{
+		Name: filepath.Join("parent", "sub", "new"),
+		Type: fs.NonRemove,
+	}, inProgress)
 	compareBatchToExpectedDirect(t, getEventPaths(a.root, ".", a), []string{"parent"})
 
 	// test aggregation in root
 	a = newAggregator(folderCfg, ctx)
 	for i := 0; i < maxFiles; i++ {
-		a.newEvent(fs.Event{strconv.Itoa(i), fs.NonRemove}, inProgress)
+		a.newEvent(fs.Event{
+			Name: strconv.Itoa(i),
+			Type: fs.NonRemove,
+		}, inProgress)
 	}
 	if len(getEventPaths(a.root, ".", a)) != maxFiles {
 		t.Errorf("Unexpected number of events stored in root")
 	}
-	a.newEvent(fs.Event{filepath.Join("parent", "sub", "new"), fs.NonRemove}, inProgress)
+	a.newEvent(fs.Event{
+		Name: filepath.Join("parent", "sub", "new"),
+		Type: fs.NonRemove,
+	}, inProgress)
 	compareBatchToExpectedDirect(t, getEventPaths(a.root, ".", a), []string{"."})
 
 	// checks that adding an event when "." is already stored is a noop
-	a.newEvent(fs.Event{"anythingelse", fs.NonRemove}, inProgress)
+	a.newEvent(fs.Event{
+		Name: "anythingelse",
+		Type: fs.NonRemove,
+	}, inProgress)
 	compareBatchToExpectedDirect(t, getEventPaths(a.root, ".", a), []string{"."})
 
 	a = newAggregator(folderCfg, ctx)
@@ -115,7 +140,10 @@ func TestAggregate(t *testing.T) {
 	}
 	for _, dir := range dirs {
 		for i := 0; i < filesPerDir; i++ {
-			a.newEvent(fs.Event{filepath.Join(dir, strconv.Itoa(i)), fs.NonRemove}, inProgress)
+			a.newEvent(fs.Event{
+				Name: filepath.Join(dir, strconv.Itoa(i)),
+				Type: fs.NonRemove,
+			}, inProgress)
 		}
 	}
 	compareBatchToExpectedDirect(t, getEventPaths(a.root, ".", a), []string{"."})
diff --git a/lib/weakhash/benchmark_test.go b/lib/weakhash/benchmark_test.go
index 791900e4e..1829e5b8a 100644
--- a/lib/weakhash/benchmark_test.go
+++ b/lib/weakhash/benchmark_test.go
@@ -42,7 +42,7 @@ func BenchmarkWeakHashAdler32(b *testing.B) {
 	hf := adler32.New()
 
 	for i := 0; i < b.N; i++ {
-		hf.Write(data)
+		_, _ = hf.Write(data)
 	}
 
 	_ = hf.Sum32()
@@ -52,7 +52,7 @@ func BenchmarkWeakHashAdler32(b *testing.B) {
 func BenchmarkWeakHashAdler32Roll(b *testing.B) {
 	data := make([]byte, size)
 	hf := adler32.New()
-	hf.Write(data)
+	_, _ = hf.Write(data)
 
 	b.ResetTimer()
 
@@ -70,7 +70,7 @@ func BenchmarkWeakHashRabinKarp64(b *testing.B) {
 	hf := rabinkarp64.New()
 
 	for i := 0; i < b.N; i++ {
-		hf.Write(data)
+		_, _ = hf.Write(data)
 	}
 
 	_ = hf.Sum64()