Enable profiling options when 'pprof' tag is set (#2813)

This commit enables cpu, mem, block, and mutex profling of the FZF
executable. To support flushing the profiles at program exit it adds
util.AtExit to register "at exit" functions and mandates that util.Exit
is used instead of os.Exit to stop the program.

Co-authored-by: Junegunn Choi <junegunn.c@gmail.com>

BUILD.md

@@ -24,13 +24,23 @@ make build
 make release
 ```
 
-> :warning: Makefile uses git commands to determine the version and the
-> revision information for `fzf --version`. So if you're building fzf from an
+> [!WARNING]
+> Makefile uses git commands to determine the version and the revision
+> information for `fzf --version`. So if you're building fzf from an
 > environment where its git information is not available, you have to manually
 > set `$FZF_VERSION` and `$FZF_REVISION`.
 >
 > e.g. `FZF_VERSION=0.24.0 FZF_REVISION=tarball make`
 
+> [!TIP]
+> To build fzf with profiling options enabled, set `TAGS=pprof`
+>
+> ```sh
+> TAGS=pprof make clean install
+> fzf --profile-cpu /tmp/cpu.pprof --profile-mem /tmp/mem.pprof \
+>     --profile-block /tmp/block.pprof --profile-mutex /tmp/mutex.pprof
+> ```
+
 Third-party libraries used
 --------------------------
 

CHANGELOG.md

@@ -1,6 +1,28 @@
 CHANGELOG
 =========
 
+0.50.0
+------
+- Added `jump` and `jump-cancel` events that are triggered when leaving `jump` mode
+  ```sh
+  # Default behavior
+  fzf --bind space:jump
+
+  # Same as jump-accept action
+  fzf --bind space:jump,jump:accept
+
+  # Accept on jump, abort on cancel
+  fzf --bind space:jump,jump:accept,jump-cancel:abort
+
+  # Change header on jump-cancel
+  fzf --bind 'space:change-header(Type jump label)+jump,jump-cancel:change-header:Jump cancelled'
+  ```
+- Added a new environment variable `$FZF_KEY` exported to the child processes. It's the name of the last key pressed.
+  ```sh
+  fzf --bind 'space:jump,jump:accept,jump-cancel:transform:[[ $FZF_KEY =~ ctrl-c ]] && echo abort'
+  ```
+- Bug fixes
+
 0.49.0
 ------
 - Ingestion performance improved by around 40% (more or less depending on options)

Makefile

@@ -79,6 +79,7 @@ all: target/$(BINARY)
 test: $(SOURCES)
 	[ -z "$$(gofmt -s -d src)" ] || (gofmt -s -d src; exit 1)
 	SHELL=/bin/sh GOOS= $(GO) test -v -tags "$(TAGS)" \
+				github.com/junegunn/fzf \
 				github.com/junegunn/fzf/src \
 				github.com/junegunn/fzf/src/algo \
 				github.com/junegunn/fzf/src/tui \

main_test.go

@@ -0,0 +1,158 @@
+package main
+
+import (
+	"fmt"
+	"go/ast"
+	"go/build"
+	"go/importer"
+	"go/parser"
+	"go/token"
+	"go/types"
+	"io/fs"
+	"os"
+	"path/filepath"
+	"sort"
+	"strings"
+	"testing"
+)
+
+func loadPackages(t *testing.T) []*build.Package {
+	wd, err := os.Getwd()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	var pkgs []*build.Package
+	seen := make(map[string]bool)
+	err = filepath.WalkDir(wd, func(path string, d fs.DirEntry, err error) error {
+		if err != nil {
+			return err
+		}
+		name := d.Name()
+		if d.IsDir() {
+			if name == "" || name[0] == '.' || name[0] == '_' || name == "vendor" || name == "tmp" {
+				return filepath.SkipDir
+			}
+			return nil
+		}
+		if d.Type().IsRegular() && filepath.Ext(name) == ".go" && !strings.HasSuffix(name, "_test.go") {
+			dir := filepath.Dir(path)
+			if !seen[dir] {
+				pkg, err := build.ImportDir(dir, build.ImportComment)
+				if err != nil {
+					return fmt.Errorf("%s: %s", dir, err)
+				}
+				if pkg.ImportPath == "" || pkg.ImportPath == "." {
+					importPath, err := filepath.Rel(wd, dir)
+					if err != nil {
+						t.Fatal(err)
+					}
+					pkg.ImportPath = filepath.ToSlash(filepath.Join("github.com/junegunn/fzf", importPath))
+				}
+
+				pkgs = append(pkgs, pkg)
+				seen[dir] = true
+			}
+		}
+		return nil
+	})
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	sort.Slice(pkgs, func(i, j int) bool {
+		return pkgs[i].ImportPath < pkgs[j].ImportPath
+	})
+	return pkgs
+}
+
+var sourceImporter = importer.ForCompiler(token.NewFileSet(), "source", nil)
+
+func checkPackageForOsExit(t *testing.T, bpkg *build.Package, allowed map[string]int) (errOsExit bool) {
+	var files []*ast.File
+	fset := token.NewFileSet()
+	for _, name := range bpkg.GoFiles {
+		filename := filepath.Join(bpkg.Dir, name)
+		af, err := parser.ParseFile(fset, filename, nil, parser.ParseComments)
+		if err != nil {
+			t.Fatal(err)
+		}
+		files = append(files, af)
+	}
+
+	info := types.Info{
+		Uses: make(map[*ast.Ident]types.Object),
+	}
+	conf := types.Config{
+		Importer: sourceImporter,
+	}
+	_, err := conf.Check(bpkg.Name, fset, files, &info)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	wd, err := os.Getwd()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	for id, obj := range info.Uses {
+		if obj.Pkg() != nil && obj.Pkg().Name() == "os" && obj.Name() == "Exit" {
+			pos := fset.Position(id.Pos())
+
+			name, err := filepath.Rel(wd, pos.Filename)
+			if err != nil {
+				t.Log(err)
+				name = pos.Filename
+			}
+			name = filepath.ToSlash(name)
+
+			// Check if the usage is allowed
+			if allowed[name] > 0 {
+				allowed[name]--
+				continue
+			}
+
+			t.Errorf("os.Exit referenced at: %s:%d:%d", name, pos.Line, pos.Column)
+			errOsExit = true
+		}
+	}
+	return errOsExit
+}
+
+// Enforce that src/util.Exit() is used instead of os.Exit by prohibiting
+// references to it anywhere else in the fzf code base.
+func TestOSExitNotAllowed(t *testing.T) {
+	if testing.Short() {
+		t.Skip("skipping: short test")
+	}
+	allowed := map[string]int{
+		"src/util/atexit.go": 1, // os.Exit allowed 1 time in "atexit.go"
+	}
+	var errOsExit bool
+	for _, pkg := range loadPackages(t) {
+		t.Run(pkg.ImportPath, func(t *testing.T) {
+			if checkPackageForOsExit(t, pkg, allowed) {
+				errOsExit = true
+			}
+		})
+	}
+	if t.Failed() && errOsExit {
+		var names []string
+		for name := range allowed {
+			names = append(names, fmt.Sprintf("%q", name))
+		}
+		sort.Strings(names)
+
+		const errMsg = `
+Test failed because os.Exit was referenced outside of the following files:
+
+    %s
+
+Use github.com/junegunn/fzf/src/util.Exit() instead to exit the program.
+This is enforced because calling os.Exit() prevents the functions
+registered with util.AtExit() from running.`
+
+		t.Errorf(errMsg, strings.Join(names, "\n    "))
+	}
+}

man/man1/fzf.1

@@ -191,7 +191,7 @@ actions are affected:
 \fBkill-word\fR
 .TP
 .BI "--jump-labels=" "CHARS"
-Label characters for \fBjump\fR and \fBjump-accept\fR
+Label characters for \fBjump\fR mode.
 .SS Layout
 .TP
 .BI "--height=" "[~]HEIGHT[%]"
@@ -982,6 +982,8 @@ fzf exports the following environment variables to its child processes.
 .br
 .BR FZF_ACTION "          The name of the last action performed"
 .br
+.BR FZF_KEY "             The name of the last key pressed"
+.br
 .BR FZF_PORT "            Port number when --listen option is used"
 .br
 
@@ -1052,21 +1054,21 @@ e.g.
 .br
 \fIctrl-]\fR
 .br
-\fIctrl-^\fR      (\fIctrl-6\fR)
+\fIctrl-^\fR         (\fIctrl-6\fR)
 .br
-\fIctrl-/\fR      (\fIctrl-_\fR)
+\fIctrl-/\fR         (\fIctrl-_\fR)
 .br
 \fIctrl-alt-[a-z]\fR
 .br
-\fIalt-[*]\fR     (Any case-sensitive single character is allowed)
+\fIalt-[*]\fR        (Any case-sensitive single character is allowed)
 .br
 \fIf[1-12]\fR
 .br
-\fIenter\fR       (\fIreturn\fR \fIctrl-m\fR)
+\fIenter\fR          (\fIreturn\fR \fIctrl-m\fR)
 .br
 \fIspace\fR
 .br
-\fIbspace\fR      (\fIbs\fR)
+\fIbackspace\fR      (\fIbspace\fR \fIbs\fR)
 .br
 \fIalt-up\fR
 .br
@@ -1080,15 +1082,15 @@ e.g.
 .br
 \fIalt-space\fR
 .br
-\fIalt-bspace\fR  (\fIalt-bs\fR)
+\fIalt-backspace\fR  (\fIalt-bspace\fR \fIalt-bs\fR)
 .br
 \fItab\fR
 .br
-\fIbtab\fR        (\fIshift-tab\fR)
+\fIshift-tab\fR      (\fIbtab\fR)
 .br
 \fIesc\fR
 .br
-\fIdel\fR
+\fIdelete\fR         (\fIdel\fR)
 .br
 \fIup\fR
 .br
@@ -1104,9 +1106,9 @@ e.g.
 .br
 \fIinsert\fR
 .br
-\fIpgup\fR        (\fIpage-up\fR)
+\fIpage-up\fR        (\fIpgup\fR)
 .br
-\fIpgdn\fR        (\fIpage-down\fR)
+\fIpage-down\fR      (\fIpgdn\fR)
 .br
 \fIshift-up\fR
 .br
@@ -1248,7 +1250,7 @@ e.g.
 
 \fIjump\fR
 .RS
-Triggered when successfully jumped to the target item in \fB--jump\fR mode.
+Triggered when successfully jumped to the target item in \fBjump\fR mode.
 
 e.g.
      \fBfzf --bind space:jump,jump:accept\fR
@@ -1256,7 +1258,7 @@ e.g.
 
 \fIjump-cancel\fR
 .RS
-Triggered when \fB--jump\fR mode is cancelled.
+Triggered when \fBjump\fR mode is cancelled.
 
 e.g.
      \fBfzf --bind space:jump,jump:accept,jump-cancel:abort\fR
@@ -1304,7 +1306,6 @@ A key or an event can be bound to one or more of the following actions.
     \fBforward-word\fR                 \fIalt-f   shift-right\fR
     \fBignore\fR
     \fBjump\fR                         (EasyMotion-like 2-keystroke movement)
-    \fBjump-accept\fR                  (jump and accept)
     \fBkill-line\fR
     \fBkill-word\fR                    \fIalt-d\fR
     \fBlast\fR                         (move to the last match; same as \fBpos(-1)\fR)

src/core.go

@@ -3,7 +3,6 @@ package fzf
 
 import (
 	"fmt"
-	"os"
 	"time"
 	"unsafe"
 
@@ -29,6 +28,8 @@ func sbytes(data string) []byte {
 
 // Run starts fzf
 func Run(opts *Options, version string, revision string) {
+	defer util.RunAtExitFuncs()
+
 	sort := opts.Sort > 0
 	sortCriteria = opts.Criteria
 
@@ -38,7 +39,7 @@ func Run(opts *Options, version string, revision string) {
 		} else {
 			fmt.Println(version)
 		}
-		os.Exit(exitOk)
+		util.Exit(exitOk)
 	}
 
 	// Event channel
@@ -189,9 +190,9 @@ func Run(opts *Options, version string, revision string) {
 			}
 		}
 		if found {
-			os.Exit(exitOk)
+			util.Exit(exitOk)
 		}
-		os.Exit(exitNoMatch)
+		util.Exit(exitNoMatch)
 	}
 
 	// Synchronous search
@@ -270,7 +271,7 @@ func Run(opts *Options, version string, revision string) {
 					if reading {
 						reader.terminate()
 					}
-					os.Exit(value.(int))
+					util.Exit(value.(int))
 				case EvtReadNew, EvtReadFin:
 					if evt == EvtReadFin && nextCommand != nil {
 						restart(*nextCommand, nextEnviron)
@@ -372,9 +373,9 @@ func Run(opts *Options, version string, revision string) {
 										opts.Printer(val.Get(i).item.AsString(opts.Ansi))
 									}
 									if count > 0 {
-										os.Exit(exitOk)
+										util.Exit(exitOk)
 									}
-									os.Exit(exitNoMatch)
+									util.Exit(exitNoMatch)
 								}
 								determine(val.final)
 							}

src/options.go

@@ -52,7 +52,7 @@ const usage = `usage: fzf [options]
     --hscroll-off=COLS     Number of screen columns to keep to the right of the
                            highlighted substring (default: 10)
     --filepath-word        Make word-wise movements respect path separators
-    --jump-labels=CHARS    Label characters for jump and jump-accept
+    --jump-labels=CHARS    Label characters for jump mode
 
   Layout
     --height=[~]HEIGHT[%]  Display fzf window below the cursor with the given
@@ -363,6 +363,10 @@ type Options struct {
 	WalkerRoot   string
 	WalkerSkip   []string
 	Version      bool
+	CPUProfile   string
+	MEMProfile   string
+	BlockProfile string
+	MutexProfile string
 }
 
 func filterNonEmpty(input []string) []string {
@@ -454,14 +458,14 @@ func defaultOptions() *Options {
 
 func help(code int) {
 	os.Stdout.WriteString(usage)
-	os.Exit(code)
+	util.Exit(code)
 }
 
 var errorContext = ""
 
 func errorExit(msg string) {
 	os.Stderr.WriteString(errorContext + msg + "\n")
-	os.Exit(exitError)
+	util.Exit(exitError)
 }
 
 func optString(arg string, prefixes ...string) (bool, string) {
@@ -666,8 +670,8 @@ func parseKeyChordsImpl(str string, message string, exit func(string)) map[tui.E
 			add(tui.CtrlM)
 		case "space":
 			chords[tui.Key(' ')] = key
-		case "bspace", "bs":
-			add(tui.BSpace)
+		case "backspace", "bspace", "bs":
+			add(tui.Backspace)
 		case "ctrl-space":
 			add(tui.CtrlSpace)
 		case "ctrl-delete":
@@ -706,8 +710,8 @@ func parseKeyChordsImpl(str string, message string, exit func(string)) map[tui.E
 			chords[tui.CtrlAltKey('m')] = key
 		case "alt-space":
 			chords[tui.AltKey(' ')] = key
-		case "alt-bs", "alt-bspace":
-			add(tui.AltBS)
+		case "alt-bs", "alt-bspace", "alt-backspace":
+			add(tui.AltBackspace)
 		case "alt-up":
 			add(tui.AltUp)
 		case "alt-down":
@@ -719,11 +723,11 @@ func parseKeyChordsImpl(str string, message string, exit func(string)) map[tui.E
 		case "tab":
 			add(tui.Tab)
 		case "btab", "shift-tab":
-			add(tui.BTab)
+			add(tui.ShiftTab)
 		case "esc":
-			add(tui.ESC)
-		case "del":
-			add(tui.Del)
+			add(tui.Esc)
+		case "delete", "del":
+			add(tui.Delete)
 		case "home":
 			add(tui.Home)
 		case "end":
@@ -731,27 +735,27 @@ func parseKeyChordsImpl(str string, message string, exit func(string)) map[tui.E
 		case "insert":
 			add(tui.Insert)
 		case "pgup", "page-up":
-			add(tui.PgUp)
+			add(tui.PageUp)
 		case "pgdn", "page-down":
-			add(tui.PgDn)
+			add(tui.PageDown)
 		case "alt-shift-up", "shift-alt-up":
-			add(tui.AltSUp)
+			add(tui.AltShiftUp)
 		case "alt-shift-down", "shift-alt-down":
-			add(tui.AltSDown)
+			add(tui.AltShiftDown)
 		case "alt-shift-left", "shift-alt-left":
-			add(tui.AltSLeft)
+			add(tui.AltShiftLeft)
 		case "alt-shift-right", "shift-alt-right":
-			add(tui.AltSRight)
+			add(tui.AltShiftRight)
 		case "shift-up":
-			add(tui.SUp)
+			add(tui.ShiftUp)
 		case "shift-down":
-			add(tui.SDown)
+			add(tui.ShiftDown)
 		case "shift-left":
-			add(tui.SLeft)
+			add(tui.ShiftLeft)
 		case "shift-right":
-			add(tui.SRight)
+			add(tui.ShiftRight)
 		case "shift-delete":
-			add(tui.SDelete)
+			add(tui.ShiftDelete)
 		case "left-click":
 			add(tui.LeftClick)
 		case "right-click":
@@ -1978,6 +1982,14 @@ func parseOptions(opts *Options, allArgs []string) {
 			opts.WalkerSkip = filterNonEmpty(strings.Split(nextString(allArgs, &i, "directory names to ignore required"), ","))
 		case "--version":
 			opts.Version = true
+		case "--profile-cpu":
+			opts.CPUProfile = nextString(allArgs, &i, "file path required: cpu")
+		case "--profile-mem":
+			opts.MEMProfile = nextString(allArgs, &i, "file path required: mem")
+		case "--profile-block":
+			opts.BlockProfile = nextString(allArgs, &i, "file path required: block")
+		case "--profile-mutex":
+			opts.MutexProfile = nextString(allArgs, &i, "file path required: mutex")
 		case "--":
 			// Ignored
 		default:
@@ -2303,6 +2315,11 @@ func ParseOptions() *Options {
 	errorContext = ""
 	parseOptions(opts, os.Args[1:])
 
+	if err := opts.initProfiling(); err != nil {
+		errorExit("failed to start pprof profiles: " + err.Error())
+	}
+
 	postProcessOptions(opts)
+
 	return opts
 }

src/options_no_pprof.go

@@ -0,0 +1,11 @@
+//go:build !pprof
+// +build !pprof
+
+package fzf
+
+func (o *Options) initProfiling() error {
+	if o.CPUProfile != "" || o.MEMProfile != "" || o.BlockProfile != "" || o.MutexProfile != "" {
+		errorExit("error: profiling not supported: FZF must be built with '-tags=pprof' to enable profiling")
+	}
+	return nil
+}

src/options_pprof.go

@@ -0,0 +1,73 @@
+//go:build pprof
+// +build pprof
+
+package fzf
+
+import (
+	"fmt"
+	"os"
+	"runtime"
+	"runtime/pprof"
+
+	"github.com/junegunn/fzf/src/util"
+)
+
+func (o *Options) initProfiling() error {
+	if o.CPUProfile != "" {
+		f, err := os.Create(o.CPUProfile)
+		if err != nil {
+			return fmt.Errorf("could not create CPU profile: %w", err)
+		}
+
+		if err := pprof.StartCPUProfile(f); err != nil {
+			return fmt.Errorf("could not start CPU profile: %w", err)
+		}
+
+		util.AtExit(func() {
+			pprof.StopCPUProfile()
+			if err := f.Close(); err != nil {
+				fmt.Fprintln(os.Stderr, "Error: closing cpu profile:", err)
+			}
+		})
+	}
+
+	stopProfile := func(name string, f *os.File) {
+		if err := pprof.Lookup(name).WriteTo(f, 0); err != nil {
+			fmt.Fprintf(os.Stderr, "Error: could not write %s profile: %v\n", name, err)
+		}
+		if err := f.Close(); err != nil {
+			fmt.Fprintf(os.Stderr, "Error: closing %s profile: %v\n", name, err)
+		}
+	}
+
+	if o.MEMProfile != "" {
+		f, err := os.Create(o.MEMProfile)
+		if err != nil {
+			return fmt.Errorf("could not create MEM profile: %w", err)
+		}
+		util.AtExit(func() {
+			runtime.GC()
+			stopProfile("allocs", f)
+		})
+	}
+
+	if o.BlockProfile != "" {
+		runtime.SetBlockProfileRate(1)
+		f, err := os.Create(o.BlockProfile)
+		if err != nil {
+			return fmt.Errorf("could not create BLOCK profile: %w", err)
+		}
+		util.AtExit(func() { stopProfile("block", f) })
+	}
+
+	if o.MutexProfile != "" {
+		runtime.SetMutexProfileFraction(1)
+		f, err := os.Create(o.MutexProfile)
+		if err != nil {
+			return fmt.Errorf("could not create MUTEX profile: %w", err)
+		}
+		util.AtExit(func() { stopProfile("mutex", f) })
+	}
+
+	return nil
+}

src/options_pprof_test.go

@@ -0,0 +1,89 @@
+//go:build pprof
+// +build pprof
+
+package fzf
+
+import (
+	"bytes"
+	"flag"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"testing"
+
+	"github.com/junegunn/fzf/src/util"
+)
+
+// runInitProfileTests is an internal flag used TestInitProfiling
+var runInitProfileTests = flag.Bool("test-init-profile", false, "run init profile tests")
+
+func TestInitProfiling(t *testing.T) {
+	if testing.Short() {
+		t.Skip("short test")
+	}
+
+	// Run this test in a separate process since it interferes with
+	// profiling and modifies the global atexit state. Without this
+	// running `go test -bench . -cpuprofile cpu.out` will fail.
+	if !*runInitProfileTests {
+		t.Parallel()
+
+		// Make sure we are not the child process.
+		if os.Getenv("_FZF_CHILD_PROC") != "" {
+			t.Fatal("already running as child process!")
+		}
+
+		cmd := exec.Command(os.Args[0],
+			"-test.timeout", "30s",
+			"-test.run", "^"+t.Name()+"$",
+			"-test-init-profile",
+		)
+		cmd.Env = append(os.Environ(), "_FZF_CHILD_PROC=1")
+
+		out, err := cmd.CombinedOutput()
+		out = bytes.TrimSpace(out)
+		if err != nil {
+			t.Fatalf("Child test process failed: %v:\n%s", err, out)
+		}
+		// Make sure the test actually ran
+		if bytes.Contains(out, []byte("no tests to run")) {
+			t.Fatalf("Failed to run test %q:\n%s", t.Name(), out)
+		}
+		return
+	}
+
+	// Child process
+
+	tempdir := t.TempDir()
+	t.Cleanup(util.RunAtExitFuncs)
+
+	o := Options{
+		CPUProfile:   filepath.Join(tempdir, "cpu.prof"),
+		MEMProfile:   filepath.Join(tempdir, "mem.prof"),
+		BlockProfile: filepath.Join(tempdir, "block.prof"),
+		MutexProfile: filepath.Join(tempdir, "mutex.prof"),
+	}
+	if err := o.initProfiling(); err != nil {
+		t.Fatal(err)
+	}
+
+	profiles := []string{
+		o.CPUProfile,
+		o.MEMProfile,
+		o.BlockProfile,
+		o.MutexProfile,
+	}
+	for _, name := range profiles {
+		if _, err := os.Stat(name); err != nil {
+			t.Errorf("Failed to create profile %s: %v", filepath.Base(name), err)
+		}
+	}
+
+	util.RunAtExitFuncs()
+
+	for _, name := range profiles {
+		if _, err := os.Stat(name); err != nil {
+			t.Errorf("Failed to write profile %s: %v", filepath.Base(name), err)
+		}
+	}
+}

src/options_test.go

@@ -170,8 +170,8 @@ func TestParseKeys(t *testing.T) {
 	check(tui.CtrlM, "Return")
 	checkEvent(tui.Key(' '), "space")
 	check(tui.Tab, "tab")
-	check(tui.BTab, "btab")
-	check(tui.ESC, "esc")
+	check(tui.ShiftTab, "btab")
+	check(tui.Esc, "esc")
 	check(tui.Up, "up")
 	check(tui.Down, "down")
 	check(tui.Left, "left")
@@ -182,16 +182,16 @@ func TestParseKeys(t *testing.T) {
 		t.Error(11)
 	}
 	check(tui.Tab, "Ctrl-I")
-	check(tui.PgUp, "page-up")
-	check(tui.PgDn, "Page-Down")
+	check(tui.PageUp, "page-up")
+	check(tui.PageDown, "Page-Down")
 	check(tui.Home, "Home")
 	check(tui.End, "End")
-	check(tui.AltBS, "Alt-BSpace")
-	check(tui.SLeft, "shift-left")
-	check(tui.SRight, "shift-right")
-	check(tui.BTab, "shift-tab")
+	check(tui.AltBackspace, "Alt-BSpace")
+	check(tui.ShiftLeft, "shift-left")
+	check(tui.ShiftRight, "shift-right")
+	check(tui.ShiftTab, "shift-tab")
 	check(tui.CtrlM, "Enter")
-	check(tui.BSpace, "bspace")
+	check(tui.Backspace, "bspace")
 }
 
 func TestParseKeysWithComma(t *testing.T) {

src/terminal.go

@@ -293,6 +293,7 @@ type Terminal struct {
 	executing          *util.AtomicBool
 	termSize           tui.TermSize
 	lastAction         actionType
+	lastKey            string
 	lastFocus          int32
 	areaLines          int
 	areaColumns        int
@@ -408,7 +409,7 @@ const (
 	actOffsetUp
 	actOffsetDown
 	actJump
-	actJumpAccept
+	actJumpAccept // XXX Deprecated in favor of jump:accept binding
 	actPrintQuery
 	actRefreshPreview
 	actReplaceQuery
@@ -460,14 +461,7 @@ const (
 )
 
 func (a actionType) Name() string {
-	name := ""
-	for i, r := range a.String()[3:] {
-		if i > 0 && r >= 'A' && r <= 'Z' {
-			name += "-"
-		}
-		name += string(r)
-	}
-	return strings.ToLower(name)
+	return util.ToKebabCase(a.String()[3:])
 }
 
 func processExecution(action actionType) bool {
@@ -546,14 +540,14 @@ func defaultKeymap() map[tui.Event][]*action {
 	add(tui.CtrlC, actAbort)
 	add(tui.CtrlG, actAbort)
 	add(tui.CtrlQ, actAbort)
-	add(tui.ESC, actAbort)
+	add(tui.Esc, actAbort)
 	add(tui.CtrlD, actDeleteCharEof)
 	add(tui.CtrlE, actEndOfLine)
 	add(tui.CtrlF, actForwardChar)
 	add(tui.CtrlH, actBackwardDeleteChar)
-	add(tui.BSpace, actBackwardDeleteChar)
+	add(tui.Backspace, actBackwardDeleteChar)
 	add(tui.Tab, actToggleDown)
-	add(tui.BTab, actToggleUp)
+	add(tui.ShiftTab, actToggleUp)
 	add(tui.CtrlJ, actDown)
 	add(tui.CtrlK, actUp)
 	add(tui.CtrlL, actClearScreen)
@@ -568,11 +562,11 @@ func defaultKeymap() map[tui.Event][]*action {
 	}
 
 	addEvent(tui.AltKey('b'), actBackwardWord)
-	add(tui.SLeft, actBackwardWord)
+	add(tui.ShiftLeft, actBackwardWord)
 	addEvent(tui.AltKey('f'), actForwardWord)
-	add(tui.SRight, actForwardWord)
+	add(tui.ShiftRight, actForwardWord)
 	addEvent(tui.AltKey('d'), actKillWord)
-	add(tui.AltBS, actBackwardKillWord)
+	add(tui.AltBackspace, actBackwardKillWord)
 
 	add(tui.Up, actUp)
 	add(tui.Down, actDown)
@@ -581,12 +575,12 @@ func defaultKeymap() map[tui.Event][]*action {
 
 	add(tui.Home, actBeginningOfLine)
 	add(tui.End, actEndOfLine)
-	add(tui.Del, actDeleteChar)
-	add(tui.PgUp, actPageUp)
-	add(tui.PgDn, actPageDown)
+	add(tui.Delete, actDeleteChar)
+	add(tui.PageUp, actPageUp)
+	add(tui.PageDown, actPageDown)
 
-	add(tui.SUp, actPreviewUp)
-	add(tui.SDown, actPreviewDown)
+	add(tui.ShiftUp, actPreviewUp)
+	add(tui.ShiftDown, actPreviewDown)
 
 	add(tui.Mouse, actMouse)
 	add(tui.LeftClick, actClick)
@@ -851,6 +845,7 @@ func (t *Terminal) environ() []string {
 	}
 	env = append(env, "FZF_QUERY="+string(t.input))
 	env = append(env, "FZF_ACTION="+t.lastAction.Name())
+	env = append(env, "FZF_KEY="+t.lastKey)
 	env = append(env, "FZF_PROMPT="+string(t.promptString))
 	env = append(env, "FZF_PREVIEW_LABEL="+t.previewLabelOpts.label)
 	env = append(env, "FZF_BORDER_LABEL="+t.borderLabelOpts.label)
@@ -3290,6 +3285,7 @@ func (t *Terminal) Loop() {
 		t.mutex.Lock()
 		previousInput := t.input
 		previousCx := t.cx
+		t.lastKey = event.KeyName()
 		events := []util.EventType{}
 		req := func(evts ...util.EventType) {
 			for _, event := range evts {

src/tui/eventtype_string.go

@@ -0,0 +1,120 @@
+// Code generated by "stringer -type=EventType"; DO NOT EDIT.
+
+package tui
+
+import "strconv"
+
+func _() {
+	// An "invalid array index" compiler error signifies that the constant values have changed.
+	// Re-run the stringer command to generate them again.
+	var x [1]struct{}
+	_ = x[Rune-0]
+	_ = x[CtrlA-1]
+	_ = x[CtrlB-2]
+	_ = x[CtrlC-3]
+	_ = x[CtrlD-4]
+	_ = x[CtrlE-5]
+	_ = x[CtrlF-6]
+	_ = x[CtrlG-7]
+	_ = x[CtrlH-8]
+	_ = x[Tab-9]
+	_ = x[CtrlJ-10]
+	_ = x[CtrlK-11]
+	_ = x[CtrlL-12]
+	_ = x[CtrlM-13]
+	_ = x[CtrlN-14]
+	_ = x[CtrlO-15]
+	_ = x[CtrlP-16]
+	_ = x[CtrlQ-17]
+	_ = x[CtrlR-18]
+	_ = x[CtrlS-19]
+	_ = x[CtrlT-20]
+	_ = x[CtrlU-21]
+	_ = x[CtrlV-22]
+	_ = x[CtrlW-23]
+	_ = x[CtrlX-24]
+	_ = x[CtrlY-25]
+	_ = x[CtrlZ-26]
+	_ = x[Esc-27]
+	_ = x[CtrlSpace-28]
+	_ = x[CtrlDelete-29]
+	_ = x[CtrlBackSlash-30]
+	_ = x[CtrlRightBracket-31]
+	_ = x[CtrlCaret-32]
+	_ = x[CtrlSlash-33]
+	_ = x[ShiftTab-34]
+	_ = x[Backspace-35]
+	_ = x[Delete-36]
+	_ = x[PageUp-37]
+	_ = x[PageDown-38]
+	_ = x[Up-39]
+	_ = x[Down-40]
+	_ = x[Left-41]
+	_ = x[Right-42]
+	_ = x[Home-43]
+	_ = x[End-44]
+	_ = x[Insert-45]
+	_ = x[ShiftUp-46]
+	_ = x[ShiftDown-47]
+	_ = x[ShiftLeft-48]
+	_ = x[ShiftRight-49]
+	_ = x[ShiftDelete-50]
+	_ = x[F1-51]
+	_ = x[F2-52]
+	_ = x[F3-53]
+	_ = x[F4-54]
+	_ = x[F5-55]
+	_ = x[F6-56]
+	_ = x[F7-57]
+	_ = x[F8-58]
+	_ = x[F9-59]
+	_ = x[F10-60]
+	_ = x[F11-61]
+	_ = x[F12-62]
+	_ = x[AltBackspace-63]
+	_ = x[AltUp-64]
+	_ = x[AltDown-65]
+	_ = x[AltLeft-66]
+	_ = x[AltRight-67]
+	_ = x[AltShiftUp-68]
+	_ = x[AltShiftDown-69]
+	_ = x[AltShiftLeft-70]
+	_ = x[AltShiftRight-71]
+	_ = x[Alt-72]
+	_ = x[CtrlAlt-73]
+	_ = x[Invalid-74]
+	_ = x[Mouse-75]
+	_ = x[DoubleClick-76]
+	_ = x[LeftClick-77]
+	_ = x[RightClick-78]
+	_ = x[SLeftClick-79]
+	_ = x[SRightClick-80]
+	_ = x[ScrollUp-81]
+	_ = x[ScrollDown-82]
+	_ = x[SScrollUp-83]
+	_ = x[SScrollDown-84]
+	_ = x[PreviewScrollUp-85]
+	_ = x[PreviewScrollDown-86]
+	_ = x[Resize-87]
+	_ = x[Change-88]
+	_ = x[BackwardEOF-89]
+	_ = x[Start-90]
+	_ = x[Load-91]
+	_ = x[Focus-92]
+	_ = x[One-93]
+	_ = x[Zero-94]
+	_ = x[Result-95]
+	_ = x[Jump-96]
+	_ = x[JumpCancel-97]
+}
+
+const _EventType_name = "RuneCtrlACtrlBCtrlCCtrlDCtrlECtrlFCtrlGCtrlHTabCtrlJCtrlKCtrlLCtrlMCtrlNCtrlOCtrlPCtrlQCtrlRCtrlSCtrlTCtrlUCtrlVCtrlWCtrlXCtrlYCtrlZEscCtrlSpaceCtrlDeleteCtrlBackSlashCtrlRightBracketCtrlCaretCtrlSlashShiftTabBackspaceDeletePageUpPageDownUpDownLeftRightHomeEndInsertShiftUpShiftDownShiftLeftShiftRightShiftDeleteF1F2F3F4F5F6F7F8F9F10F11F12AltBackspaceAltUpAltDownAltLeftAltRightAltShiftUpAltShiftDownAltShiftLeftAltShiftRightAltCtrlAltInvalidMouseDoubleClickLeftClickRightClickSLeftClickSRightClickScrollUpScrollDownSScrollUpSScrollDownPreviewScrollUpPreviewScrollDownResizeChangeBackwardEOFStartLoadFocusOneZeroResultJumpJumpCancel"
+
+var _EventType_index = [...]uint16{0, 4, 9, 14, 19, 24, 29, 34, 39, 44, 47, 52, 57, 62, 67, 72, 77, 82, 87, 92, 97, 102, 107, 112, 117, 122, 127, 132, 135, 144, 154, 167, 183, 192, 201, 209, 218, 224, 230, 238, 240, 244, 248, 253, 257, 260, 266, 273, 282, 291, 301, 312, 314, 316, 318, 320, 322, 324, 326, 328, 330, 333, 336, 339, 351, 356, 363, 370, 378, 388, 400, 412, 425, 428, 435, 442, 447, 458, 467, 477, 487, 498, 506, 516, 525, 536, 551, 568, 574, 580, 591, 596, 600, 605, 608, 612, 618, 622, 632}
+
+func (i EventType) String() string {
+	if i < 0 || i >= EventType(len(_EventType_index)-1) {
+		return "EventType(" + strconv.FormatInt(int64(i), 10) + ")"
+	}
+	return _EventType_name[_EventType_index[i]:_EventType_index[i+1]]
+}

src/tui/light.go

@@ -245,7 +245,7 @@ func (r *LightRenderer) getBytesInternal(buffer []byte, nonblock bool) []byte {
 	}
 
 	retries := 0
-	if c == ESC.Int() || nonblock {
+	if c == Esc.Int() || nonblock {
 		retries = r.escDelay / escPollInterval
 	}
 	buffer = append(buffer, byte(c))
@@ -260,7 +260,7 @@ func (r *LightRenderer) getBytesInternal(buffer []byte, nonblock bool) []byte {
 				continue
 			}
 			break
-		} else if c == ESC.Int() && pc != c {
+		} else if c == Esc.Int() && pc != c {
 			retries = r.escDelay / escPollInterval
 		} else {
 			retries = 0
@@ -300,7 +300,7 @@ func (r *LightRenderer) GetChar() Event {
 	case CtrlQ.Byte():
 		return Event{CtrlQ, 0, nil}
 	case 127:
-		return Event{BSpace, 0, nil}
+		return Event{Backspace, 0, nil}
 	case 0:
 		return Event{CtrlSpace, 0, nil}
 	case 28:
@@ -311,7 +311,7 @@ func (r *LightRenderer) GetChar() Event {
 		return Event{CtrlCaret, 0, nil}
 	case 31:
 		return Event{CtrlSlash, 0, nil}
-	case ESC.Byte():
+	case Esc.Byte():
 		ev := r.escSequence(&sz)
 		// Second chance
 		if ev.Type == Invalid {
@@ -327,7 +327,7 @@ func (r *LightRenderer) GetChar() Event {
 	}
 	char, rsz := utf8.DecodeRune(r.buffer)
 	if char == utf8.RuneError {
-		return Event{ESC, 0, nil}
+		return Event{Esc, 0, nil}
 	}
 	sz = rsz
 	return Event{Rune, char, nil}
@@ -335,7 +335,7 @@ func (r *LightRenderer) GetChar() Event {
 
 func (r *LightRenderer) escSequence(sz *int) Event {
 	if len(r.buffer) < 2 {
-		return Event{ESC, 0, nil}
+		return Event{Esc, 0, nil}
 	}
 
 	loc := offsetRegexpBegin.FindIndex(r.buffer)
@@ -349,15 +349,15 @@ func (r *LightRenderer) escSequence(sz *int) Event {
 		return CtrlAltKey(rune(r.buffer[1] + 'a' - 1))
 	}
 	alt := false
-	if len(r.buffer) > 2 && r.buffer[1] == ESC.Byte() {
+	if len(r.buffer) > 2 && r.buffer[1] == Esc.Byte() {
 		r.buffer = r.buffer[1:]
 		alt = true
 	}
 	switch r.buffer[1] {
-	case ESC.Byte():
-		return Event{ESC, 0, nil}
+	case Esc.Byte():
+		return Event{Esc, 0, nil}
 	case 127:
-		return Event{AltBS, 0, nil}
+		return Event{AltBackspace, 0, nil}
 	case '[', 'O':
 		if len(r.buffer) < 3 {
 			return Event{Invalid, 0, nil}
@@ -386,7 +386,7 @@ func (r *LightRenderer) escSequence(sz *int) Event {
 			}
 			return Event{Up, 0, nil}
 		case 'Z':
-			return Event{BTab, 0, nil}
+			return Event{ShiftTab, 0, nil}
 		case 'H':
 			return Event{Home, 0, nil}
 		case 'F':
@@ -434,7 +434,7 @@ func (r *LightRenderer) escSequence(sz *int) Event {
 				return Event{Invalid, 0, nil} // INS
 			case '3':
 				if r.buffer[3] == '~' {
-					return Event{Del, 0, nil}
+					return Event{Delete, 0, nil}
 				}
 				if len(r.buffer) == 6 && r.buffer[5] == '~' {
 					*sz = 6
@@ -442,16 +442,16 @@ func (r *LightRenderer) escSequence(sz *int) Event {
 					case '5':
 						return Event{CtrlDelete, 0, nil}
 					case '2':
-						return Event{SDelete, 0, nil}
+						return Event{ShiftDelete, 0, nil}
 					}
 				}
 				return Event{Invalid, 0, nil}
 			case '4':
 				return Event{End, 0, nil}
 			case '5':
-				return Event{PgUp, 0, nil}
+				return Event{PageUp, 0, nil}
 			case '6':
-				return Event{PgDn, 0, nil}
+				return Event{PageDown, 0, nil}
 			case '7':
 				return Event{Home, 0, nil}
 			case '8':
@@ -489,16 +489,29 @@ func (r *LightRenderer) escSequence(sz *int) Event {
 					}
 					*sz = 6
 					switch r.buffer[4] {
-					case '1', '2', '3', '5':
+					case '1', '2', '3', '4', '5':
+						//                   Kitty      iTerm2     WezTerm
+						// SHIFT-ARROW       "\e[1;2D"
+						// ALT-SHIFT-ARROW   "\e[1;4D"  "\e[1;10D" "\e[1;4D"
+						// CTRL-SHIFT-ARROW  "\e[1;6D"             N/A
+						// CMD-SHIFT-ARROW   "\e[1;10D" N/A        N/A ("\e[1;2D")
 						alt := r.buffer[4] == '3'
-						altShift := r.buffer[4] == '1' && r.buffer[5] == '0'
 						char := r.buffer[5]
-						if altShift {
+						altShift := false
+						if r.buffer[4] == '1' && r.buffer[5] == '0' {
+							altShift = true
 							if len(r.buffer) < 7 {
 								return Event{Invalid, 0, nil}
 							}
 							*sz = 7
 							char = r.buffer[6]
+						} else if r.buffer[4] == '4' {
+							altShift = true
+							if len(r.buffer) < 6 {
+								return Event{Invalid, 0, nil}
+							}
+							*sz = 6
+							char = r.buffer[5]
 						}
 						switch char {
 						case 'A':
@@ -506,33 +519,33 @@ func (r *LightRenderer) escSequence(sz *int) Event {
 								return Event{AltUp, 0, nil}
 							}
 							if altShift {
-								return Event{AltSUp, 0, nil}
+								return Event{AltShiftUp, 0, nil}
 							}
-							return Event{SUp, 0, nil}
+							return Event{ShiftUp, 0, nil}
 						case 'B':
 							if alt {
 								return Event{AltDown, 0, nil}
 							}
 							if altShift {
-								return Event{AltSDown, 0, nil}
+								return Event{AltShiftDown, 0, nil}
 							}
-							return Event{SDown, 0, nil}
+							return Event{ShiftDown, 0, nil}
 						case 'C':
 							if alt {
 								return Event{AltRight, 0, nil}
 							}
 							if altShift {
-								return Event{AltSRight, 0, nil}
+								return Event{AltShiftRight, 0, nil}
 							}
-							return Event{SRight, 0, nil}
+							return Event{ShiftRight, 0, nil}
 						case 'D':
 							if alt {
 								return Event{AltLeft, 0, nil}
 							}
 							if altShift {
-								return Event{AltSLeft, 0, nil}
+								return Event{AltShiftLeft, 0, nil}
 							}
-							return Event{SLeft, 0, nil}
+							return Event{ShiftLeft, 0, nil}
 						}
 					} // r.buffer[4]
 				} // r.buffer[3]

src/tui/light_unix.go

@@ -58,7 +58,7 @@ func openTtyIn() *os.File {
 			}
 		}
 		fmt.Fprintln(os.Stderr, "Failed to open "+consoleDevice)
-		os.Exit(2)
+		util.Exit(2)
 	}
 	return in
 }

src/tui/tcell.go

@@ -320,16 +320,16 @@ func (r *FullscreenRenderer) GetChar() Event {
 			switch ev.Rune() {
 			case 0:
 				if ctrl {
-					return Event{BSpace, 0, nil}
+					return Event{Backspace, 0, nil}
 				}
 			case rune(tcell.KeyCtrlH):
 				switch {
 				case ctrl:
 					return keyfn('h')
 				case alt:
-					return Event{AltBS, 0, nil}
+					return Event{AltBackspace, 0, nil}
 				case none, shift:
-					return Event{BSpace, 0, nil}
+					return Event{Backspace, 0, nil}
 				}
 			}
 		case tcell.KeyCtrlI:
@@ -382,17 +382,17 @@ func (r *FullscreenRenderer) GetChar() Event {
 		// section 3: (Alt)+Backspace2
 		case tcell.KeyBackspace2:
 			if alt {
-				return Event{AltBS, 0, nil}
+				return Event{AltBackspace, 0, nil}
 			}
-			return Event{BSpace, 0, nil}
+			return Event{Backspace, 0, nil}
 
 		// section 4: (Alt+Shift)+Key(Up|Down|Left|Right)
 		case tcell.KeyUp:
 			if altShift {
-				return Event{AltSUp, 0, nil}
+				return Event{AltShiftUp, 0, nil}
 			}
 			if shift {
-				return Event{SUp, 0, nil}
+				return Event{ShiftUp, 0, nil}
 			}
 			if alt {
 				return Event{AltUp, 0, nil}
@@ -400,10 +400,10 @@ func (r *FullscreenRenderer) GetChar() Event {
 			return Event{Up, 0, nil}
 		case tcell.KeyDown:
 			if altShift {
-				return Event{AltSDown, 0, nil}
+				return Event{AltShiftDown, 0, nil}
 			}
 			if shift {
-				return Event{SDown, 0, nil}
+				return Event{ShiftDown, 0, nil}
 			}
 			if alt {
 				return Event{AltDown, 0, nil}
@@ -411,10 +411,10 @@ func (r *FullscreenRenderer) GetChar() Event {
 			return Event{Down, 0, nil}
 		case tcell.KeyLeft:
 			if altShift {
-				return Event{AltSLeft, 0, nil}
+				return Event{AltShiftLeft, 0, nil}
 			}
 			if shift {
-				return Event{SLeft, 0, nil}
+				return Event{ShiftLeft, 0, nil}
 			}
 			if alt {
 				return Event{AltLeft, 0, nil}
@@ -422,10 +422,10 @@ func (r *FullscreenRenderer) GetChar() Event {
 			return Event{Left, 0, nil}
 		case tcell.KeyRight:
 			if altShift {
-				return Event{AltSRight, 0, nil}
+				return Event{AltShiftRight, 0, nil}
 			}
 			if shift {
-				return Event{SRight, 0, nil}
+				return Event{ShiftRight, 0, nil}
 			}
 			if alt {
 				return Event{AltRight, 0, nil}
@@ -442,17 +442,17 @@ func (r *FullscreenRenderer) GetChar() Event {
 				return Event{CtrlDelete, 0, nil}
 			}
 			if shift {
-				return Event{SDelete, 0, nil}
+				return Event{ShiftDelete, 0, nil}
 			}
-			return Event{Del, 0, nil}
+			return Event{Delete, 0, nil}
 		case tcell.KeyEnd:
 			return Event{End, 0, nil}
 		case tcell.KeyPgUp:
-			return Event{PgUp, 0, nil}
+			return Event{PageUp, 0, nil}
 		case tcell.KeyPgDn:
-			return Event{PgDn, 0, nil}
+			return Event{PageDown, 0, nil}
 		case tcell.KeyBacktab:
-			return Event{BTab, 0, nil}
+			return Event{ShiftTab, 0, nil}
 		case tcell.KeyF1:
 			return Event{F1, 0, nil}
 		case tcell.KeyF2:
@@ -498,7 +498,7 @@ func (r *FullscreenRenderer) GetChar() Event {
 
 		// section 7: Esc
 		case tcell.KeyEsc:
-			return Event{ESC, 0, nil}
+			return Event{Esc, 0, nil}
 		}
 	}
 

src/tui/tcell_test.go

@@ -102,22 +102,22 @@ func TestGetCharEventKey(t *testing.T) {
 		// KeyBackspace2 is alias for KeyDEL = 0x7F (ASCII) (allegedly unused by Windows)
 		// KeyDelete = 0x2E (VK_DELETE constant in Windows)
 		// KeyBackspace is alias for KeyBS = 0x08 (ASCII) (implicit alias with KeyCtrlH)
-		{giveKey{tcell.KeyBackspace2, 0, tcell.ModNone}, wantKey{BSpace, 0, nil}}, // fabricated
-		{giveKey{tcell.KeyBackspace2, 0, tcell.ModAlt}, wantKey{AltBS, 0, nil}},   // fabricated
-		{giveKey{tcell.KeyDEL, 0, tcell.ModNone}, wantKey{BSpace, 0, nil}},        // fabricated, unhandled
-		{giveKey{tcell.KeyDelete, 0, tcell.ModNone}, wantKey{Del, 0, nil}},
-		{giveKey{tcell.KeyDelete, 0, tcell.ModAlt}, wantKey{Del, 0, nil}},
+		{giveKey{tcell.KeyBackspace2, 0, tcell.ModNone}, wantKey{Backspace, 0, nil}},   // fabricated
+		{giveKey{tcell.KeyBackspace2, 0, tcell.ModAlt}, wantKey{AltBackspace, 0, nil}}, // fabricated
+		{giveKey{tcell.KeyDEL, 0, tcell.ModNone}, wantKey{Backspace, 0, nil}},          // fabricated, unhandled
+		{giveKey{tcell.KeyDelete, 0, tcell.ModNone}, wantKey{Delete, 0, nil}},
+		{giveKey{tcell.KeyDelete, 0, tcell.ModAlt}, wantKey{Delete, 0, nil}},
 		{giveKey{tcell.KeyBackspace, 0, tcell.ModNone}, wantKey{Invalid, 0, nil}},                                                  // fabricated, unhandled
 		{giveKey{tcell.KeyBS, 0, tcell.ModNone}, wantKey{Invalid, 0, nil}},                                                         // fabricated, unhandled
 		{giveKey{tcell.KeyCtrlH, 0, tcell.ModNone}, wantKey{Invalid, 0, nil}},                                                      // fabricated, unhandled
-		{giveKey{tcell.KeyCtrlH, rune(tcell.KeyCtrlH), tcell.ModNone}, wantKey{BSpace, 0, nil}},                                    // actual "Backspace" keystroke
-		{giveKey{tcell.KeyCtrlH, rune(tcell.KeyCtrlH), tcell.ModAlt}, wantKey{AltBS, 0, nil}},                                      // actual "Alt+Backspace" keystroke
-		{giveKey{tcell.KeyDEL, rune(tcell.KeyDEL), tcell.ModCtrl}, wantKey{BSpace, 0, nil}},                                        // actual "Ctrl+Backspace" keystroke
-		{giveKey{tcell.KeyCtrlH, rune(tcell.KeyCtrlH), tcell.ModShift}, wantKey{BSpace, 0, nil}},                                   // actual "Shift+Backspace" keystroke
-		{giveKey{tcell.KeyCtrlH, 0, tcell.ModCtrl | tcell.ModAlt}, wantKey{BSpace, 0, nil}},                                        // actual "Ctrl+Alt+Backspace" keystroke
-		{giveKey{tcell.KeyCtrlH, 0, tcell.ModCtrl | tcell.ModShift}, wantKey{BSpace, 0, nil}},                                      // actual "Ctrl+Shift+Backspace" keystroke
-		{giveKey{tcell.KeyCtrlH, rune(tcell.KeyCtrlH), tcell.ModShift | tcell.ModAlt}, wantKey{AltBS, 0, nil}},                     // actual "Shift+Alt+Backspace" keystroke
-		{giveKey{tcell.KeyCtrlH, 0, tcell.ModCtrl | tcell.ModAlt | tcell.ModShift}, wantKey{BSpace, 0, nil}},                       // actual "Ctrl+Shift+Alt+Backspace" keystroke
+		{giveKey{tcell.KeyCtrlH, rune(tcell.KeyCtrlH), tcell.ModNone}, wantKey{Backspace, 0, nil}},                                 // actual "Backspace" keystroke
+		{giveKey{tcell.KeyCtrlH, rune(tcell.KeyCtrlH), tcell.ModAlt}, wantKey{AltBackspace, 0, nil}},                               // actual "Alt+Backspace" keystroke
+		{giveKey{tcell.KeyDEL, rune(tcell.KeyDEL), tcell.ModCtrl}, wantKey{Backspace, 0, nil}},                                     // actual "Ctrl+Backspace" keystroke
+		{giveKey{tcell.KeyCtrlH, rune(tcell.KeyCtrlH), tcell.ModShift}, wantKey{Backspace, 0, nil}},                                // actual "Shift+Backspace" keystroke
+		{giveKey{tcell.KeyCtrlH, 0, tcell.ModCtrl | tcell.ModAlt}, wantKey{Backspace, 0, nil}},                                     // actual "Ctrl+Alt+Backspace" keystroke
+		{giveKey{tcell.KeyCtrlH, 0, tcell.ModCtrl | tcell.ModShift}, wantKey{Backspace, 0, nil}},                                   // actual "Ctrl+Shift+Backspace" keystroke
+		{giveKey{tcell.KeyCtrlH, rune(tcell.KeyCtrlH), tcell.ModShift | tcell.ModAlt}, wantKey{AltBackspace, 0, nil}},              // actual "Shift+Alt+Backspace" keystroke
+		{giveKey{tcell.KeyCtrlH, 0, tcell.ModCtrl | tcell.ModAlt | tcell.ModShift}, wantKey{Backspace, 0, nil}},                    // actual "Ctrl+Shift+Alt+Backspace" keystroke
 		{giveKey{tcell.KeyCtrlH, rune(tcell.KeyCtrlH), tcell.ModCtrl}, wantKey{CtrlH, 0, nil}},                                     // actual "Ctrl+H" keystroke
 		{giveKey{tcell.KeyCtrlH, rune(tcell.KeyCtrlH), tcell.ModCtrl | tcell.ModAlt}, wantKey{CtrlAlt, 'h', nil}},                  // fabricated "Ctrl+Alt+H" keystroke
 		{giveKey{tcell.KeyCtrlH, rune(tcell.KeyCtrlH), tcell.ModCtrl | tcell.ModShift}, wantKey{CtrlH, 0, nil}},                    // actual "Ctrl+Shift+H" keystroke
@@ -126,8 +126,8 @@ func TestGetCharEventKey(t *testing.T) {
 		// section 4: (Alt+Shift)+Key(Up|Down|Left|Right)
 		{giveKey{tcell.KeyUp, 0, tcell.ModNone}, wantKey{Up, 0, nil}},
 		{giveKey{tcell.KeyDown, 0, tcell.ModAlt}, wantKey{AltDown, 0, nil}},
-		{giveKey{tcell.KeyLeft, 0, tcell.ModShift}, wantKey{SLeft, 0, nil}},
-		{giveKey{tcell.KeyRight, 0, tcell.ModShift | tcell.ModAlt}, wantKey{AltSRight, 0, nil}},
+		{giveKey{tcell.KeyLeft, 0, tcell.ModShift}, wantKey{ShiftLeft, 0, nil}},
+		{giveKey{tcell.KeyRight, 0, tcell.ModShift | tcell.ModAlt}, wantKey{AltShiftRight, 0, nil}},
 		{giveKey{tcell.KeyUpLeft, 0, tcell.ModNone}, wantKey{Invalid, 0, nil}},    // fabricated, unhandled
 		{giveKey{tcell.KeyUpRight, 0, tcell.ModNone}, wantKey{Invalid, 0, nil}},   // fabricated, unhandled
 		{giveKey{tcell.KeyDownLeft, 0, tcell.ModNone}, wantKey{Invalid, 0, nil}},  // fabricated, unhandled
@@ -161,11 +161,11 @@ func TestGetCharEventKey(t *testing.T) {
 
 		// section 7: Esc
 		// KeyEsc and KeyEscape are aliases for KeyESC
-		{giveKey{tcell.KeyEsc, rune(tcell.KeyEsc), tcell.ModNone}, wantKey{ESC, 0, nil}},               // fabricated
-		{giveKey{tcell.KeyESC, rune(tcell.KeyESC), tcell.ModNone}, wantKey{ESC, 0, nil}},               // unhandled
-		{giveKey{tcell.KeyEscape, rune(tcell.KeyEscape), tcell.ModNone}, wantKey{ESC, 0, nil}},         // fabricated, unhandled
-		{giveKey{tcell.KeyESC, rune(tcell.KeyESC), tcell.ModCtrl}, wantKey{ESC, 0, nil}},               // actual Ctrl+[ keystroke
-		{giveKey{tcell.KeyCtrlLeftSq, rune(tcell.KeyCtrlLeftSq), tcell.ModCtrl}, wantKey{ESC, 0, nil}}, // fabricated, unhandled
+		{giveKey{tcell.KeyEsc, rune(tcell.KeyEsc), tcell.ModNone}, wantKey{Esc, 0, nil}},               // fabricated
+		{giveKey{tcell.KeyESC, rune(tcell.KeyESC), tcell.ModNone}, wantKey{Esc, 0, nil}},               // unhandled
+		{giveKey{tcell.KeyEscape, rune(tcell.KeyEscape), tcell.ModNone}, wantKey{Esc, 0, nil}},         // fabricated, unhandled
+		{giveKey{tcell.KeyESC, rune(tcell.KeyESC), tcell.ModCtrl}, wantKey{Esc, 0, nil}},               // actual Ctrl+[ keystroke
+		{giveKey{tcell.KeyCtrlLeftSq, rune(tcell.KeyCtrlLeftSq), tcell.ModCtrl}, wantKey{Esc, 0, nil}}, // fabricated, unhandled
 
 		// section 8: Invalid
 		{giveKey{tcell.KeyRune, 'a', tcell.ModMeta}, wantKey{Rune, 'a', nil}}, // fabricated
@@ -259,7 +259,7 @@ Quick reference
 37					LeftClick
 38					RightClick
 39					BTab
-40					BSpace
+40					Backspace
 41					Del
 42					PgUp
 43					PgDn
@@ -272,7 +272,7 @@ Quick reference
 50					Insert
 51					SUp
 52					SDown
-53					SLeft
+53					ShiftLeft
 54					SRight
 55					F1
 56					F2
@@ -288,15 +288,15 @@ Quick reference
 66					F12
 67					Change
 68					BackwardEOF
-69					AltBS
+69					AltBackspace
 70					AltUp
 71					AltDown
 72					AltLeft
 73					AltRight
 74					AltSUp
 75					AltSDown
-76					AltSLeft
-77					AltSRight
+76					AltShiftLeft
+77					AltShiftRight
 78					Alt
 79					CtrlAlt
 ..

src/tui/tui.go

@@ -6,10 +6,13 @@ import (
 	"strconv"
 	"time"
 
+	"github.com/junegunn/fzf/src/util"
 	"github.com/rivo/uniseg"
 )
 
 // Types of user action
+//
+//go:generate stringer -type=EventType
 type EventType int
 
 const (
@@ -41,7 +44,7 @@ const (
 	CtrlX
 	CtrlY
 	CtrlZ
-	ESC
+	Esc
 	CtrlSpace
 	CtrlDelete
 
@@ -51,27 +54,12 @@ const (
 	CtrlCaret
 	CtrlSlash
 
-	Invalid
-	Resize
-	Mouse
-	DoubleClick
-	LeftClick
-	RightClick
-	SLeftClick
-	SRightClick
-	ScrollUp
-	ScrollDown
-	SScrollUp
-	SScrollDown
-	PreviewScrollUp
-	PreviewScrollDown
+	ShiftTab
+	Backspace
 
-	BTab
-	BSpace
-
-	Del
-	PgUp
-	PgDn
+	Delete
+	PageUp
+	PageDown
 
 	Up
 	Down
@@ -81,11 +69,11 @@ const (
 	End
 	Insert
 
-	SUp
-	SDown
-	SLeft
-	SRight
-	SDelete
+	ShiftUp
+	ShiftDown
+	ShiftLeft
+	ShiftRight
+	ShiftDelete
 
 	F1
 	F2
@@ -100,6 +88,38 @@ const (
 	F11
 	F12
 
+	AltBackspace
+
+	AltUp
+	AltDown
+	AltLeft
+	AltRight
+
+	AltShiftUp
+	AltShiftDown
+	AltShiftLeft
+	AltShiftRight
+
+	Alt
+	CtrlAlt
+
+	Invalid
+
+	Mouse
+	DoubleClick
+	LeftClick
+	RightClick
+	SLeftClick
+	SRightClick
+	ScrollUp
+	ScrollDown
+	SScrollUp
+	SScrollDown
+	PreviewScrollUp
+	PreviewScrollDown
+
+	// Events
+	Resize
 	Change
 	BackwardEOF
 	Start
@@ -110,21 +130,6 @@ const (
 	Result
 	Jump
 	JumpCancel
-
-	AltBS
-
-	AltUp
-	AltDown
-	AltLeft
-	AltRight
-
-	AltSUp
-	AltSDown
-	AltSLeft
-	AltSRight
-
-	Alt
-	CtrlAlt
 )
 
 func (t EventType) AsEvent() Event {
@@ -144,6 +149,31 @@ func (e Event) Comparable() Event {
 	return Event{e.Type, e.Char, nil}
 }
 
+func (e Event) KeyName() string {
+	if e.Type >= Invalid {
+		return ""
+	}
+
+	switch e.Type {
+	case Rune:
+		return string(e.Char)
+	case Alt:
+		return "alt-" + string(e.Char)
+	case CtrlAlt:
+		return "ctrl-alt-" + string(e.Char)
+	case CtrlBackSlash:
+		return "ctrl-\\"
+	case CtrlRightBracket:
+		return "ctrl-]"
+	case CtrlCaret:
+		return "ctrl-^"
+	case CtrlSlash:
+		return "ctrl-/"
+	}
+
+	return util.ToKebabCase(e.Type.String())
+}
+
 func Key(r rune) Event {
 	return Event{Rune, r, nil}
 }
@@ -648,7 +678,7 @@ func NoColorTheme() *ColorTheme {
 
 func errorExit(message string) {
 	fmt.Fprintln(os.Stderr, message)
-	os.Exit(2)
+	util.Exit(2)
 }
 
 func init() {

src/util/atexit.go

@@ -0,0 +1,38 @@
+package util
+
+import (
+	"os"
+	"sync"
+)
+
+var atExitFuncs []func()
+
+// AtExit registers the function fn to be called on program termination.
+// The functions will be called in reverse order they were registered.
+func AtExit(fn func()) {
+	if fn == nil {
+		panic("AtExit called with nil func")
+	}
+	once := &sync.Once{}
+	atExitFuncs = append(atExitFuncs, func() {
+		once.Do(fn)
+	})
+}
+
+// RunAtExitFuncs runs any functions registered with AtExit().
+func RunAtExitFuncs() {
+	fns := atExitFuncs
+	for i := len(fns) - 1; i >= 0; i-- {
+		fns[i]()
+	}
+}
+
+// Exit executes any functions registered with AtExit() then exits the program
+// with os.Exit(code).
+//
+// NOTE: It must be used instead of os.Exit() since calling os.Exit() terminates
+// the program before any of the AtExit functions can run.
+func Exit(code int) {
+	defer os.Exit(code)
+	RunAtExitFuncs()
+}

src/util/atexit_test.go

@@ -0,0 +1,24 @@
+package util
+
+import (
+	"reflect"
+	"testing"
+)
+
+func TestAtExit(t *testing.T) {
+	want := []int{3, 2, 1, 0}
+	var called []int
+	for i := 0; i < 4; i++ {
+		n := i
+		AtExit(func() { called = append(called, n) })
+	}
+	RunAtExitFuncs()
+	if !reflect.DeepEqual(called, want) {
+		t.Errorf("AtExit: want call order: %v got: %v", want, called)
+	}
+
+	RunAtExitFuncs()
+	if !reflect.DeepEqual(called, want) {
+		t.Error("AtExit: should only call exit funcs once")
+	}
+}

src/util/util.go

@@ -176,3 +176,15 @@ func RepeatToFill(str string, length int, limit int) string {
 	}
 	return output
 }
+
+// ToKebabCase converts the given CamelCase string to kebab-case
+func ToKebabCase(s string) string {
+	name := ""
+	for i, r := range s {
+		if i > 0 && r >= 'A' && r <= 'Z' {
+			name += "-"
+		}
+		name += string(r)
+	}
+	return strings.ToLower(name)
+}