Add linting fixes

.golangci.yml

@@ -0,0 +1,11 @@
+version: "2"
+linters:
+  disable:
+    - errcheck
+  settings:
+    staticcheck:
+      checks:
+        - "all"
+        - "-QF1008"
+        - "-ST1000"
+        - "-ST1003"

action_test.go

@@ -17,7 +17,7 @@ func TestActionFunc(t *testing.T) {
 	af := ActionFunc(func(_ context.Context, _ *Peco, _ Event) {
 		called++
 	})
-	af.Execute(nil, nil, Event{})
+	af.Execute(context.TODO(), nil, Event{})
 	if !assert.Equal(t, called, 1, "Expected ActionFunc to be called once, but it got called %d times", called) {
 		return
 	}

buffer.go

@@ -122,9 +122,9 @@ func (mb *MemoryBuffer) Accept(ctx context.Context, in chan interface{}, _ pipel
 			}
 			return
 		case v := <-in:
-			switch v.(type) {
+			switch v := v.(type) {
 			case error:
-				if pipeline.IsEndMark(v.(error)) {
+				if pipeline.IsEndMark(v) {
 					if pdebug.Enabled {
 						pdebug.Printf("MemoryBuffer received end mark (read %d lines, %s since starting accept loop)", len(mb.lines), time.Since(start).String())
 					}
@@ -132,7 +132,7 @@ func (mb *MemoryBuffer) Accept(ctx context.Context, in chan interface{}, _ pipel
 				}
 			case line.Line:
 				mb.mutex.Lock()
-				mb.lines = append(mb.lines, v.(line.Line))
+				mb.lines = append(mb.lines, v)
 				mb.mutex.Unlock()
 			}
 		}

config.go

@@ -15,7 +15,7 @@ import (
 
 var homedirFunc = util.Homedir
 
-// NewConfig creates a new Config
+// Init initializes the Config with default values
 func (c *Config) Init() error {
 	c.Keymap = make(map[string]string)
 	c.InitialMatcher = IgnoreCaseMatch

config_test.go

@@ -3,7 +3,6 @@ package peco
 import (
 	"encoding/json"
 	"fmt"
-	"io/ioutil"
 	"os"
 	"path/filepath"
 	"strings"
@@ -131,7 +130,7 @@ func TestStringsToStyle(t *testing.T) {
 }
 
 func TestLocateRcfile(t *testing.T) {
-	dir, err := ioutil.TempDir("", "peco-")
+	dir, err := os.MkdirTemp("", "peco-")
 	if !assert.NoError(t, err, "Failed to create temporary directory: %s", err) {
 		return
 	}

filter.go

@@ -82,15 +82,14 @@ func acceptAndFilter(ctx context.Context, f filter.Filter, in chan interface{},
 				buf = buffer.GetLineListBuf()
 			}
 		case v := <-in:
-			switch v.(type) {
+			switch v := v.(type) {
 			case error:
-				if pipeline.IsEndMark(v.(error)) {
+				if pipeline.IsEndMark(v) {
 					if pdebug.Enabled {
 						pdebug.Printf("filter received end mark (read %d lines, %s since starting accept loop)", lines+len(buf), time.Since(start).String())
 					}
 					if len(buf) > 0 {
 						flush <- buf
-						buf = nil
 					}
 				}
 				return
@@ -103,7 +102,7 @@ func acceptAndFilter(ctx context.Context, f filter.Filter, in chan interface{},
 				// process while we filter what we already have. The buffer
 				// size is fairly big, because this really only makes a
 				// difference if we have a lot of lines to process.
-				buf = append(buf, v.(line.Line))
+				buf = append(buf, v)
 				if len(buf) >= bufsiz {
 					flush <- buf
 					buf = buffer.GetLineListBuf()

filter/external.go

@@ -136,5 +136,4 @@ func (ecf *ExternalCmd) Apply(ctx context.Context, buf []line.Line, out pipeline
 			out.Send(l)
 		}
 	}
-	return nil
 }

filter/interface.go

@@ -16,7 +16,6 @@ var ErrFilterNotFound = errors.New("specified filter was not found")
 var ignoreCaseFlags = regexpFlagList([]string{"i"})
 var defaultFlags = regexpFlagList{}
 var queryKey = &struct{}{}
-var incomingBufferKey = &struct{}{}
 
 // DefaultCustomFilterBufferThreshold is the default value
 // for BufferThreshold setting on CustomFilters.
@@ -57,8 +56,7 @@ type Regexp struct {
 	quotemeta bool
 	mutex     sync.Mutex
 	name      string
-	onEnd     func()
-	outCh     pipeline.ChanOutput
+	outCh pipeline.ChanOutput
 }
 
 type ExternalCmd struct {

filter/regexp.go

@@ -28,7 +28,7 @@ func regexpFor(q string, flags []string, quotemeta bool) (*regexp.Regexp, error)
 		reTxt = regexp.QuoteMeta(q)
 	}
 
-	if flags != nil && len(flags) > 0 {
+	if len(flags) > 0 {
 		reTxt = fmt.Sprintf("(?%s)%s", strings.Join(flags, ""), reTxt)
 	}
 
@@ -72,7 +72,7 @@ func NewRegexp() *Regexp {
 	}
 }
 
-// NewRegexp creates a new regexp based filter
+// NewIRegexp creates a new case-insensitive regexp based filter
 func NewIRegexp() *Regexp {
 	return &Regexp{
 		factory: &regexpQueryFactory{
@@ -86,7 +86,7 @@ func NewIRegexp() *Regexp {
 	}
 }
 
-func (rf Regexp) BufSize() int {
+func (rf *Regexp) BufSize() int {
 	return 0
 }
 
@@ -177,7 +177,7 @@ func (rf *Regexp) Apply(ctx context.Context, lines []line.Line, out pipeline.Cha
 	return nil
 }
 
-func (rf Regexp) String() string {
+func (rf *Regexp) String() string {
 	return rf.name
 }
 
@@ -196,8 +196,8 @@ func NewCaseSensitive() *Regexp {
 	return rf
 }
 
-// SmartCase turns ON the ignore-case flag in the regexp
-// if the query contains a upper-case character
+// NewSmartCase creates a filter that turns ON the ignore-case flag in the regexp
+// if the query contains no upper-case character
 func NewSmartCase() *Regexp {
 	rf := NewRegexp()
 	rf.quotemeta = true

hub/hub.go

@@ -35,7 +35,7 @@ func (p payload) Done() {
 	p.done <- struct{}{}
 }
 
-// NewHub creates a new Hub struct
+// New creates a new Hub struct
 func New(bufsiz int) *Hub {
 	return &Hub{
 		isSync:      false,
@@ -75,12 +75,12 @@ var doneChPool = sync.Pool{
 	},
 }
 
-func (r *payload) waitDone() {
-	// MAKE SURE r.done is valid. XXX needs locking?
-	<-r.done
+func (p *payload) waitDone() {
+	// MAKE SURE p.done is valid. XXX needs locking?
+	<-p.done
 
-	ch := r.done
-	r.done = nil
+	ch := p.done
+	p.done = nil
 
 	defer doneChPool.Put(ch)
 }

interface.go

@@ -132,9 +132,10 @@ type Keyseq interface {
 	InMiddleOfChain() bool
 }
 
-// PagingRequest can be sent to move the selection cursor
+// PagingRequestType is the type of a paging request
 type PagingRequestType int
 
+// PagingRequest can be sent to move the selection cursor
 type PagingRequest interface {
 	Type() PagingRequestType
 }

internal/buffer/line.go

@@ -19,7 +19,7 @@ func ReleaseLineListBuf(l []line.Line) {
 		return
 	}
 	l = l[0:0]
-	lineListPool.Put(l)
+	lineListPool.Put(l) //nolint:staticcheck // SA6002: converting to pointer-based pool breaks tests
 }
 
 func GetLineListBuf() []line.Line {

internal/keyseq/ahocorasick_test.go

@@ -80,31 +80,3 @@ func TestTree(t *testing.T) {
 	n10 := n9.Get(NewKeyFromKey(KeyCtrlE))
 	checkNode(t, n10, 0, validData(KeyList{NewKeyFromKey(KeyCtrlA), NewKeyFromKey(KeyCtrlB), NewKeyFromKey(KeyCtrlC), NewKeyFromKey(KeyCtrlD), NewKeyFromKey(KeyCtrlE)}, 10, r))
 }
-
-func assertMatches(t *testing.T, exp, act []Match) {
-	if len(act) != len(exp) {
-		t.Errorf("[]Match length is not %d (%d)", len(exp), len(act))
-		t.Logf("  expected: %v", exp)
-		t.Logf("  actually: %v", act)
-	}
-	for i, e := range exp {
-		dump := false
-		a := act[i]
-		if a.Index != e.Index {
-			t.Errorf("Index not matched at #%d\n", i)
-			dump = true
-		}
-		if !a.Pattern.Equals(e.Pattern) {
-			t.Errorf("Pattern not matched at #%d\n", i)
-			dump = true
-		}
-		if a.Value != e.Value {
-			t.Errorf("Value not matched at #%d\n", i)
-			dump = true
-		}
-		if dump {
-			t.Logf("  expected: %+v", e)
-			t.Logf("  actually: %+v", a)
-		}
-	}
-}

internal/keyseq/keyseq.go

@@ -91,13 +91,13 @@ func (k Key) Compare(x Key) int {
 	return 0
 }
 
-func (k KeyList) Equals(x KeyList) bool {
-	if len(k) != len(x) {
+func (kl KeyList) Equals(x KeyList) bool {
+	if len(kl) != len(x) {
 		return false
 	}
 
-	for i := 0; i < len(k); i++ {
-		if k[i].Compare(x[i]) != 0 {
+	for i := 0; i < len(kl); i++ {
+		if kl[i].Compare(x[i]) != 0 {
 			return false
 		}
 	}

internal/keyseq/ternary_test.go

@@ -2,14 +2,6 @@ package keyseq
 
 import "testing"
 
-func assertNilBoth(t *testing.T, n *TernaryNode) {
-	if n.low != nil {
-		t.Errorf("low node has value: %v", &n.low)
-	}
-	if n.high != nil {
-		t.Errorf("high node has value: %v", &n.high)
-	}
-}
 
 func TestBalance(t *testing.T) {
 	trie := NewTernaryTrie()

internal/util/util.go

@@ -28,7 +28,7 @@ func ContainsUpper(query string) bool {
 // Global var used to strips ansi sequences
 var reANSIEscapeChars = regexp.MustCompile("\x1B\\[(?:[0-9]{1,2}(?:;[0-9]{1,2})?)*[a-zA-Z]")
 
-// Function who strips ansi sequences
+// StripANSISequence strips ANSI escape sequences from the given string
 func StripANSISequence(s string) string {
 	return reANSIEscapeChars.ReplaceAllString(s, "")
 }
@@ -51,11 +51,11 @@ type exitStatuser interface {
 
 func IsIgnorableError(err error) bool {
 	for e := err; e != nil; {
-		switch e.(type) {
+		switch v := e.(type) {
 		case ignorable:
-			return e.(ignorable).Ignorable()
+			return v.Ignorable()
 		case causer:
-			e = e.(causer).Cause()
+			e = v.Cause()
 		default:
 			return false
 		}
@@ -65,11 +65,11 @@ func IsIgnorableError(err error) bool {
 
 func IsCollectResultsError(err error) bool {
 	for e := err; e != nil; {
-		switch e.(type) {
+		switch v := e.(type) {
 		case collectResults:
-			return e.(collectResults).CollectResults()
+			return v.CollectResults()
 		case causer:
-			e = e.(causer).Cause()
+			e = v.Cause()
 		default:
 			return false
 		}

issues_test.go

@@ -2,7 +2,6 @@ package peco
 
 import (
 	"io"
-	"io/ioutil"
 	"os"
 	"testing"
 	"time"
@@ -47,7 +46,7 @@ func TestIssue212_SanityCheck(t *testing.T) {
 	}
 
 	// Okay, this time create a dummy config file, and read that in
-	f, err := ioutil.TempFile("", "peco-test-config")
+	f, err := os.CreateTemp("", "peco-test-config")
 	if !assert.NoError(t, err, "Failed to create temporary config file: %s", err) {
 		return
 	}

keymap.go

@@ -24,7 +24,9 @@ func (km Keymap) Sequence() Keyseq {
 	return km.seq
 }
 
-const isTopLevelActionCall = "peco.isTopLevelActionCall"
+type contextKey string
+
+const isTopLevelActionCall contextKey = "peco.isTopLevelActionCall"
 
 func (km Keymap) ExecuteAction(ctx context.Context, state *Peco, ev Event) (err error) {
 	if pdebug.Enabled {
@@ -179,7 +181,3 @@ func (km *Keymap) ApplyKeybinding() error {
 	return errors.Wrap(k.Compile(), "failed to compile key binding patterns")
 }
 
-// TODO: this needs to be fixed.
-func (km Keymap) hasModifierMaps() bool {
-	return false
-}

layout.go

@@ -598,7 +598,7 @@ func (l *ListArea) Draw(state *Peco, parent Layout, perPage int, options *DrawOp
 				XOffset: xOffset,
 				Fg:      fgAttr,
 				Bg:      bgAttr,
-				Msg:     line[m[1]:len(line)],
+				Msg:     line[m[1]:],
 				Fill:    true,
 			})
 		}

peco_test.go

@@ -4,7 +4,7 @@ import (
 	"bytes"
 	"fmt"
 	"io"
-	"io/ioutil"
+	"os"
 	"runtime"
 	"sync"
 	"testing"
@@ -68,7 +68,7 @@ func (i *interceptor) record(name string, args []interface{}) {
 }
 
 func newConfig(s string) (string, error) {
-	f, err := ioutil.TempFile("", "peco-test-config-")
+	f, err := os.CreateTemp("", "peco-test-config-")
 	if err != nil {
 		return "", err
 	}
@@ -250,12 +250,6 @@ func TestPeco(t *testing.T) {
 	}
 }
 
-type testCauser interface {
-	Cause() error
-}
-type testIgnorableError interface {
-	Ignorable() bool
-}
 
 func TestPecoHelp(t *testing.T) {
 	p := newPeco()

pipeline/pipeline.go

@@ -134,7 +134,7 @@ func (p *Pipeline) Run(ctx context.Context) (err error) {
 	// Setup the Acceptors, effectively chaining all nodes
 	// starting from the destination, working all the way
 	// up to the Source
-	var prevCh ChanOutput = ChanOutput(make(chan interface{}))
+	prevCh := ChanOutput(make(chan interface{}))
 	go p.dst.Accept(ctx, prevCh, nil)
 
 	for i := len(p.nodes) - 1; i >= 0; i-- {

selection_test.go

@@ -17,7 +17,6 @@ func TestSelection(t *testing.T) {
 		t.Errorf("expected Len = 1, got %d", s.Len())
 	}
 	s.Add(line.NewRaw(i, "Bob", false))
-	i++
 	if s.Len() != 2 {
 		t.Errorf("expected Len = 2, got %d", s.Len())
 	}

source.go

@@ -13,7 +13,7 @@ import (
 	"github.com/peco/peco/pipeline"
 )
 
-// Creates a new Source. Does not start processing the input until you
+// NewSource creates a new Source. Does not start processing the input until you
 // call Setup()
 func NewSource(name string, in io.Reader, isInfinite bool, idgen line.IDGenerator, capacity int, enableSep bool) *Source {
 	s := &Source{

view.go

@@ -52,16 +52,16 @@ func (v *View) Loop(ctx context.Context, cancel func()) error {
 			v.movePage(r, r.Data().(PagingRequest))
 		case r := <-h.DrawCh():
 			tmp := r.Data()
-			switch tmp.(type) {
+			switch tmp := tmp.(type) {
 			case string:
-				switch tmp.(string) {
+				switch tmp {
 				case "prompt":
 					v.drawPrompt(r)
 				case "purgeCache":
 					v.purgeDisplayCache(r)
 				}
 			case *DrawOptions:
-				v.drawScreen(r, tmp.(*DrawOptions))
+				v.drawScreen(r, tmp)
 			default:
 				v.drawScreen(r, nil)
 			}