x/tools: remove dead code

These unused functions and methods were discovered by a (work in
progress) dead function analyzer.

Change-Id: Iaa9c5fd4f06bdcd5d7c6e194bcc24d6b37df8f4c
Reviewed-on: https://go-review.googlesource.com/c/tools/+/639675
Auto-Submit: Alan Donovan <[email protected]>
Reviewed-by: Robert Findley <[email protected]>
LUCI-TryBot-Result: Go LUCI <[email protected]>

Author: adonovan

cmd/splitdwarf/splitdwarf.go

@@ -358,6 +358,7 @@ func CreateMmapFile(outDwarf string, size int64) (*os.File, []byte) {
 	return dwarfFile, buffer
 }
 
+// (dead code; retained for debugging)
 func describe(exem *macho.FileTOC) {
 	note("Type = %s, Flags=0x%x", exem.Type, uint32(exem.Flags))
 	for i, l := range exem.Loads {

cmd/ssadump/main.go

@@ -188,11 +188,6 @@ func doMain() error {
 // e.g. --flag=one --flag=two would produce []string{"one", "two"}.
 type stringListValue []string
 
-func newStringListValue(val []string, p *[]string) *stringListValue {
-	*p = val
-	return (*stringListValue)(p)
-}
-
 func (ss *stringListValue) Get() interface{} { return []string(*ss) }
 
 func (ss *stringListValue) String() string { return fmt.Sprintf("%q", *ss) }

cmd/stringer/endtoend_test.go

@@ -93,20 +93,6 @@ func typeName(fname string) string {
 	return fmt.Sprintf("%c%s", base[0]+'A'-'a', base[1:len(base)-len(".go")])
 }
 
-func moreTests(t *testing.T, dirname, prefix string) []string {
-	x, err := os.ReadDir(dirname)
-	if err != nil {
-		// error, but try the rest of the tests
-		t.Errorf("can't read type param tess from %s: %v", dirname, err)
-		return nil
-	}
-	names := make([]string, len(x))
-	for i, f := range x {
-		names[i] = prefix + "/" + f.Name()
-	}
-	return names
-}
-
 // TestTags verifies that the -tags flag works as advertised.
 func TestTags(t *testing.T) {
 	stringer := stringerPath(t)

container/intsets/sparse.go

@@ -287,14 +287,6 @@ func (s *Sparse) next(b *block) *block {
 	return b.next
 }
 
-// prev returns the previous block in the list, or end if b is the first block.
-func (s *Sparse) prev(b *block) *block {
-	if b.prev == &s.root {
-		return &none
-	}
-	return b.prev
-}
-
 // IsEmpty reports whether the set s is empty.
 func (s *Sparse) IsEmpty() bool {
 	return s.root.next == nil || s.root.offset == MaxInt
@@ -1077,6 +1069,7 @@ func (s *Sparse) AppendTo(slice []int) []int {
 // -- Testing/debugging ------------------------------------------------
 
 // check returns an error if the representation invariants of s are violated.
+// (unused; retained for debugging)
 func (s *Sparse) check() error {
 	s.init()
 	if s.root.empty() {

copyright/copyright.go

@@ -16,6 +16,7 @@ import (
 	"strings"
 )
 
+// (used only by tests)
 func checkCopyright(dir string) ([]string, error) {
 	var files []string
 	err := filepath.WalkDir(dir, func(path string, d fs.DirEntry, err error) error {

go/analysis/internal/analysisflags/flags.go

@@ -250,21 +250,12 @@ const (
 	setFalse
 )
 
-func triStateFlag(name string, value triState, usage string) *triState {
-	flag.Var(&value, name, usage)
-	return &value
-}
-
 // triState implements flag.Value, flag.Getter, and flag.boolFlag.
 // They work like boolean flags: we can say vet -printf as well as vet -printf=true
 func (ts *triState) Get() interface{} {
 	return *ts == setTrue
 }
 
-func (ts triState) isTrue() bool {
-	return ts == setTrue
-}
-
 func (ts *triState) Set(value string) error {
 	b, err := strconv.ParseBool(value)
 	if err != nil {

go/expect/expect.go

@@ -120,10 +120,3 @@ func MatchBefore(fset *token.FileSet, readFile ReadFile, end token.Pos, pattern
 	}
 	return f.Pos(startOffset + matchStart), f.Pos(startOffset + matchEnd), nil
 }
-
-func lineEnd(f *token.File, line int) token.Pos {
-	if line >= f.LineCount() {
-		return token.Pos(f.Base() + f.Size())
-	}
-	return f.LineStart(line + 1)
-}

go/packages/gopackages/main.go

@@ -248,11 +248,6 @@ func (app *application) print(lpkg *packages.Package) {
 // e.g. --flag=one --flag=two would produce []string{"one", "two"}.
 type stringListValue []string
 
-func newStringListValue(val []string, p *[]string) *stringListValue {
-	*p = val
-	return (*stringListValue)(p)
-}
-
 func (ss *stringListValue) Get() interface{} { return []string(*ss) }
 
 func (ss *stringListValue) String() string { return fmt.Sprintf("%q", *ss) }

go/packages/packages_test.go

@@ -2999,30 +2999,6 @@ func constant(p *packages.Package, name string) *types.Const {
 	return c.(*types.Const)
 }
 
-func copyAll(srcPath, dstPath string) error {
-	return filepath.Walk(srcPath, func(path string, info os.FileInfo, _ error) error {
-		if info.IsDir() {
-			return nil
-		}
-		contents, err := os.ReadFile(path)
-		if err != nil {
-			return err
-		}
-		rel, err := filepath.Rel(srcPath, path)
-		if err != nil {
-			return err
-		}
-		dstFilePath := strings.Replace(filepath.Join(dstPath, rel), "definitelynot_go.mod", "go.mod", -1)
-		if err := os.MkdirAll(filepath.Dir(dstFilePath), 0755); err != nil {
-			return err
-		}
-		if err := os.WriteFile(dstFilePath, contents, 0644); err != nil {
-			return err
-		}
-		return nil
-	})
-}
-
 func TestExportFile(t *testing.T) {
 	// This used to trigger the log.Fatal in loadFromExportData.
 	// See go.dev/issue/45584.

go/ssa/dom.go

@@ -318,6 +318,7 @@ func printDomTreeText(buf *bytes.Buffer, v *BasicBlock, indent int) {
 
 // printDomTreeDot prints the dominator tree of f in AT&T GraphViz
 // (.dot) format.
+// (unused; retained for debugging)
 func printDomTreeDot(buf *bytes.Buffer, f *Function) {
 	fmt.Fprintln(buf, "//", f)
 	fmt.Fprintln(buf, "digraph domtree {")

go/ssa/interp/external.go

@@ -303,15 +303,6 @@ func ext۰time۰Sleep(fr *frame, args []value) value {
 	return nil
 }
 
-func valueToBytes(v value) []byte {
-	in := v.([]value)
-	b := make([]byte, len(in))
-	for i := range in {
-		b[i] = in[i].(byte)
-	}
-	return b
-}
-
 func ext۰os۰Getenv(fr *frame, args []value) value {
 	name := args[0].(string)
 	switch name {

go/ssa/util.go

@@ -14,6 +14,7 @@ import (
 	"io"
 	"os"
 	"sync"
+	_ "unsafe" // for go:linkname hack
 
 	"golang.org/x/tools/go/types/typeutil"
 	"golang.org/x/tools/internal/typeparams"
@@ -408,14 +409,6 @@ func (canon *canonizer) instantiateMethod(m *types.Func, targs []types.Type, ctx
 }
 
 // Exposed to ssautil using the linkname hack.
+//
+//go:linkname isSyntactic golang.org/x/tools/go/ssa.isSyntactic
 func isSyntactic(pkg *Package) bool { return pkg.syntax }
-
-// mapValues returns a new unordered array of map values.
-func mapValues[K comparable, V any](m map[K]V) []V {
-	vals := make([]V, 0, len(m))
-	for _, fn := range m {
-		vals = append(vals, fn)
-	}
-	return vals
-
-}

internal/diff/lcs/old.go

@@ -199,6 +199,7 @@ func (e *editGraph) bdone(D, k int) (bool, lcs) {
 }
 
 // run the backward algorithm, until success or up to the limit on D.
+// (used only by tests)
 func backward(e *editGraph) lcs {
 	e.setBackward(0, 0, e.ux)
 	if ok, ans := e.bdone(0, 0); ok {

internal/jsonrpc2_v2/jsonrpc2.go

@@ -112,15 +112,6 @@ func (a *async) done() {
 	close(a.ready)
 }
 
-func (a *async) isDone() bool {
-	select {
-	case <-a.ready:
-		return true
-	default:
-		return false
-	}
-}
-
 func (a *async) wait() error {
 	<-a.ready
 	err := <-a.firstErr

internal/jsonrpc2_v2/serve_go116.go

@@ -8,12 +8,7 @@
 package jsonrpc2
 
 import (
-	"errors"
 	"net"
 )
 
 var errClosed = net.ErrClosed
-
-func isErrClosed(err error) bool {
-	return errors.Is(err, errClosed)
-}

internal/jsonrpc2_v2/serve_pre116.go

@@ -9,22 +9,8 @@ package jsonrpc2
 
 import (
 	"errors"
-	"strings"
 )
 
 // errClosed is an error with the same string as net.ErrClosed,
 // which was added in Go 1.16.
 var errClosed = errors.New("use of closed network connection")
-
-// isErrClosed reports whether err ends in the same string as errClosed.
-func isErrClosed(err error) bool {
-	// As of Go 1.16, this could be 'errors.Is(err, net.ErrClosing)', but
-	// unfortunately gopls still requires compatibility with
-	// (otherwise-unsupported) older Go versions.
-	//
-	// In the meantime, this error string has not changed on any supported Go
-	// version, and is not expected to change in the future.
-	// This is not ideal, but since the worst that could happen here is some
-	// superfluous logging, it is acceptable.
-	return strings.HasSuffix(err.Error(), "use of closed network connection")
-}

internal/refactor/inline/util.go

@@ -22,9 +22,6 @@ func is[T any](x any) bool {
 	return ok
 }
 
-// TODO(adonovan): use go1.21's slices.Clone.
-func clone[T any](slice []T) []T { return append([]T{}, slice...) }
-
 // TODO(adonovan): use go1.21's slices.Index.
 func index[T comparable](slice []T, x T) int {
 	for i, elem := range slice {