x/tools: remove workarounds for Go <1.23

Change-Id: I740769d6ed117bf140c9894b4464b3d3f7f326f1
Reviewed-on: https://go-review.googlesource.com/c/tools/+/653655
Auto-Submit: Alan Donovan <[email protected]>
Reviewed-by: Robert Findley <[email protected]>
LUCI-TryBot-Result: Go LUCI <[email protected]>

Author: adonovan

cmd/deadcode/deadcode.go

@@ -15,11 +15,13 @@ import (
 	"go/types"
 	"io"
 	"log"
+	"maps"
 	"os"
 	"path/filepath"
 	"regexp"
 	"runtime"
 	"runtime/pprof"
+	"slices"
 	"sort"
 	"strings"
 	"text/template"
@@ -290,9 +292,7 @@ func main() {
 
 	// Build array of jsonPackage objects.
 	var packages []any
-	pkgpaths := keys(byPkgPath)
-	sort.Strings(pkgpaths)
-	for _, pkgpath := range pkgpaths {
+	for _, pkgpath := range slices.Sorted(maps.Keys(byPkgPath)) {
 		if !filter.MatchString(pkgpath) {
 			continue
 		}
@@ -303,7 +303,7 @@ func main() {
 		// declaration order. This tends to keep related
 		// methods such as (T).Marshal and (*T).Unmarshal
 		// together better than sorting.
-		fns := keys(m)
+		fns := slices.Collect(maps.Keys(m))
 		sort.Slice(fns, func(i, j int) bool {
 			xposn := prog.Fset.Position(fns[i].Pos())
 			yposn := prog.Fset.Position(fns[j].Pos())
@@ -368,7 +368,7 @@ func prettyName(fn *ssa.Function, qualified bool) string {
 		// anonymous?
 		if fn.Parent() != nil {
 			format(fn.Parent())
-			i := index(fn.Parent().AnonFuncs, fn)
+			i := slices.Index(fn.Parent().AnonFuncs, fn)
 			fmt.Fprintf(&buf, "$%d", i+1)
 			return
 		}
@@ -427,7 +427,7 @@ func pathSearch(roots []*ssa.Function, res *rta.Result, targets map[*ssa.Functio
 	// Sort roots into preferred order.
 	importsTesting := func(fn *ssa.Function) bool {
 		isTesting := func(p *types.Package) bool { return p.Path() == "testing" }
-		return containsFunc(fn.Pkg.Pkg.Imports(), isTesting)
+		return slices.ContainsFunc(fn.Pkg.Pkg.Imports(), isTesting)
 	}
 	sort.Slice(roots, func(i, j int) bool {
 		x, y := roots[i], roots[j]
@@ -461,7 +461,7 @@ func pathSearch(roots []*ssa.Function, res *rta.Result, targets map[*ssa.Functio
 					for {
 						edge := seen[node]
 						if edge == nil {
-							reverse(path)
+							slices.Reverse(path)
 							return path
 						}
 						path = append(path, edge)
@@ -565,43 +565,3 @@ type jsonPosition struct {
 func (p jsonPosition) String() string {
 	return fmt.Sprintf("%s:%d:%d", p.File, p.Line, p.Col)
 }
-
-// -- from the future --
-
-// TODO(adonovan): use go1.22's slices and maps packages.
-
-func containsFunc[S ~[]E, E any](s S, f func(E) bool) bool {
-	return indexFunc(s, f) >= 0
-}
-
-func indexFunc[S ~[]E, E any](s S, f func(E) bool) int {
-	for i := range s {
-		if f(s[i]) {
-			return i
-		}
-	}
-	return -1
-}
-
-func index[S ~[]E, E comparable](s S, v E) int {
-	for i := range s {
-		if v == s[i] {
-			return i
-		}
-	}
-	return -1
-}
-
-func reverse[S ~[]E, E any](s S) {
-	for i, j := 0, len(s)-1; i < j; i, j = i+1, j-1 {
-		s[i], s[j] = s[j], s[i]
-	}
-}
-
-func keys[M ~map[K]V, K comparable, V any](m M) []K {
-	r := make([]K, 0, len(m))
-	for k := range m {
-		r = append(r, k)
-	}
-	return r
-}

go/analysis/analysistest/analysistest.go

@@ -7,12 +7,12 @@ package analysistest
 
 import (
 	"bytes"
-	"cmp"
 	"fmt"
 	"go/format"
 	"go/token"
 	"go/types"
 	"log"
+	"maps"
 	"os"
 	"path/filepath"
 	"regexp"
@@ -215,7 +215,7 @@ func RunWithSuggestedFixes(t Testing, dir string, a *analysis.Analyzer, patterns
 		// Because the checking is driven by original
 		// filenames, there is no way to express that a fix
 		// (e.g. extract declaration) creates a new file.
-		for _, filename := range sortedKeys(allFilenames) {
+		for _, filename := range slices.Sorted(maps.Keys(allFilenames)) {
 			// Read the original file.
 			content, err := os.ReadFile(filename)
 			if err != nil {
@@ -266,7 +266,7 @@ func RunWithSuggestedFixes(t Testing, dir string, a *analysis.Analyzer, patterns
 				// Form #2: all suggested fixes are represented by a single file.
 				want := ar.Comment
 				var accumulated []diff.Edit
-				for _, message := range sortedKeys(fixEdits) {
+				for _, message := range slices.Sorted(maps.Keys(fixEdits)) {
 					for _, fix := range fixEdits[message] {
 						accumulated = merge(filename, message, accumulated, fix[filename])
 					}
@@ -768,13 +768,3 @@ func sanitize(gopath, filename string) string {
 	prefix := gopath + string(os.PathSeparator) + "src" + string(os.PathSeparator)
 	return filepath.ToSlash(strings.TrimPrefix(filename, prefix))
 }
-
-// TODO(adonovan): use better stuff from go1.23.
-func sortedKeys[K cmp.Ordered, V any](m map[K]V) []K {
-	keys := make([]K, 0, len(m))
-	for k := range m {
-		keys = append(keys, k)
-	}
-	slices.Sort(keys)
-	return keys
-}

go/callgraph/vta/graph.go

@@ -633,12 +633,12 @@ func (b *builder) call(c ssa.CallInstruction) {
 		return
 	}
 
-	siteCallees(c, b.callees)(func(f *ssa.Function) bool {
+	for f := range siteCallees(c, b.callees) {
 		addArgumentFlows(b, c, f)
 
 		site, ok := c.(ssa.Value)
 		if !ok {
-			return true // go or defer
+			continue // go or defer
 		}
 
 		results := f.Signature.Results()
@@ -653,8 +653,7 @@ func (b *builder) call(c ssa.CallInstruction) {
 				b.addInFlowEdge(resultVar{f: f, index: i}, local)
 			}
 		}
-		return true
-	})
+	}
 }
 
 func addArgumentFlows(b *builder, c ssa.CallInstruction, f *ssa.Function) {

go/callgraph/vta/propagation.go

@@ -6,6 +6,7 @@ package vta
 
 import (
 	"go/types"
+	"iter"
 	"slices"
 
 	"golang.org/x/tools/go/callgraph/vta/internal/trie"
@@ -113,11 +114,9 @@ type propType struct {
 // the role of a map from nodes to a set of propTypes.
 type propTypeMap map[node]*trie.MutMap
 
-// propTypes returns a go1.23 iterator for the propTypes associated with
+// propTypes returns an iterator for the propTypes associated with
 // node `n` in map `ptm`.
-func (ptm propTypeMap) propTypes(n node) func(yield func(propType) bool) {
-	// TODO: when x/tools uses go1.23, change callers to use range-over-func
-	// (https://go.dev/issue/65237).
+func (ptm propTypeMap) propTypes(n node) iter.Seq[propType] {
 	return func(yield func(propType) bool) {
 		if types := ptm[n]; types != nil {
 			types.M.Range(func(_ uint64, elem any) bool {

go/callgraph/vta/propagation_test.go

@@ -98,10 +98,9 @@ func nodeToTypeString(pMap propTypeMap) map[string]string {
 	nodeToTypeStr := make(map[string]string)
 	for node := range pMap {
 		var propStrings []string
-		pMap.propTypes(node)(func(prop propType) bool {
+		for prop := range pMap.propTypes(node) {
 			propStrings = append(propStrings, propTypeString(prop))
-			return true
-		})
+		}
 		sort.Strings(propStrings)
 		nodeToTypeStr[node.String()] = strings.Join(propStrings, ";")
 	}

go/callgraph/vta/utils.go

@@ -6,6 +6,7 @@ package vta
 
 import (
 	"go/types"
+	"iter"
 
 	"golang.org/x/tools/go/ssa"
 	"golang.org/x/tools/internal/typeparams"
@@ -147,10 +148,8 @@ func sliceArrayElem(t types.Type) types.Type {
 	}
 }
 
-// siteCallees returns a go1.23 iterator for the callees for call site `c`.
-func siteCallees(c ssa.CallInstruction, callees calleesFunc) func(yield func(*ssa.Function) bool) {
-	// TODO: when x/tools uses go1.23, change callers to use range-over-func
-	// (https://go.dev/issue/65237).
+// siteCallees returns an iterator for the callees for call site `c`.
+func siteCallees(c ssa.CallInstruction, callees calleesFunc) iter.Seq[*ssa.Function] {
 	return func(yield func(*ssa.Function) bool) {
 		for _, callee := range callees(c) {
 			if !yield(callee) {

go/callgraph/vta/vta.go

@@ -126,12 +126,11 @@ func (c *constructor) resolves(call ssa.CallInstruction) []*ssa.Function {
 	// Cover the case of dynamic higher-order and interface calls.
 	var res []*ssa.Function
 	resolved := resolve(call, c.types, c.cache)
-	siteCallees(call, c.callees)(func(f *ssa.Function) bool {
+	for f := range siteCallees(call, c.callees) {
 		if _, ok := resolved[f]; ok {
 			res = append(res, f)
 		}
-		return true
-	})
+	}
 	return res
 }
 
@@ -140,12 +139,11 @@ func (c *constructor) resolves(call ssa.CallInstruction) []*ssa.Function {
 func resolve(c ssa.CallInstruction, types propTypeMap, cache methodCache) map[*ssa.Function]empty {
 	fns := make(map[*ssa.Function]empty)
 	n := local{val: c.Common().Value}
-	types.propTypes(n)(func(p propType) bool {
+	for p := range types.propTypes(n) {
 		for _, f := range propFunc(p, c, cache) {
 			fns[f] = empty{}
 		}
-		return true
-	})
+	}
 	return fns
 }
 

go/ssa/builder.go

@@ -82,6 +82,8 @@ import (
 	"runtime"
 	"sync"
 
+	"slices"
+
 	"golang.org/x/tools/internal/typeparams"
 	"golang.org/x/tools/internal/versions"
 )
@@ -2021,8 +2023,8 @@ func (b *builder) forStmtGo122(fn *Function, s *ast.ForStmt, label *lblock) {
 		// Remove instructions for phi, load, and store.
 		// lift() will remove the unused i_next *Alloc.
 		isDead := func(i Instruction) bool { return dead[i] }
-		loop.Instrs = removeInstrsIf(loop.Instrs, isDead)
-		post.Instrs = removeInstrsIf(post.Instrs, isDead)
+		loop.Instrs = slices.DeleteFunc(loop.Instrs, isDead)
+		post.Instrs = slices.DeleteFunc(post.Instrs, isDead)
 	}
 }
 

go/ssa/lift.go

@@ -43,6 +43,7 @@ import (
 	"go/token"
 	"math/big"
 	"os"
+	"slices"
 
 	"golang.org/x/tools/internal/typeparams"
 )
@@ -105,23 +106,7 @@ func buildDomFrontier(fn *Function) domFrontier {
 }
 
 func removeInstr(refs []Instruction, instr Instruction) []Instruction {
-	return removeInstrsIf(refs, func(i Instruction) bool { return i == instr })
-}
-
-func removeInstrsIf(refs []Instruction, p func(Instruction) bool) []Instruction {
-	// TODO(taking): replace with go1.22 slices.DeleteFunc.
-	i := 0
-	for _, ref := range refs {
-		if p(ref) {
-			continue
-		}
-		refs[i] = ref
-		i++
-	}
-	for j := i; j != len(refs); j++ {
-		refs[j] = nil // aid GC
-	}
-	return refs[:i]
+	return slices.DeleteFunc(refs, func(i Instruction) bool { return i == instr })
 }
 
 // lift replaces local and new Allocs accessed only with

go/types/internal/play/play.go

@@ -430,12 +430,3 @@ textarea { width: 6in; }
 body { color: gray; }
 div#out { font-family: monospace; font-size: 80%; }
 `
-
-// TODO(adonovan): use go1.21 built-in.
-func min(x, y int) int {
-	if x < y {
-		return x
-	} else {
-		return y
-	}
-}

gopls/internal/cache/parsego/parse.go

@@ -27,7 +27,6 @@ import (
 	"golang.org/x/tools/gopls/internal/label"
 	"golang.org/x/tools/gopls/internal/protocol"
 	"golang.org/x/tools/gopls/internal/util/astutil"
-	"golang.org/x/tools/gopls/internal/util/bug"
 	"golang.org/x/tools/gopls/internal/util/safetoken"
 	"golang.org/x/tools/internal/astutil/cursor"
 	"golang.org/x/tools/internal/diff"
@@ -65,39 +64,8 @@ func Parse(ctx context.Context, fset *token.FileSet, uri protocol.DocumentURI, s
 	}
 	// Inv: file != nil.
 
-	// Workaround for #70162 (missing File{Start,End} when
-	// parsing empty file) with go1.23.
-	//
-	// When parsing an empty file, or one without a valid
-	// package declaration, the go1.23 parser bails out before
-	// setting FileStart and End.
-	//
-	// This leaves us no way to find the original
-	// token.File that ParseFile created, so as a
-	// workaround, we recreate the token.File, and
-	// populate the FileStart and FileEnd fields.
-	//
-	// See also #53202.
 	tokenFile := func(file *ast.File) *token.File {
-		tok := fset.File(file.FileStart)
-		if tok == nil {
-			// Invalid File.FileStart (also File.{Package,Name.Pos}).
-			if file.Package.IsValid() {
-				bug.Report("ast.File has valid Package but no FileStart")
-			}
-			if file.Name.Pos().IsValid() {
-				bug.Report("ast.File has valid Name.Pos but no FileStart")
-			}
-			tok = fset.AddFile(uri.Path(), -1, len(src))
-			tok.SetLinesForContent(src)
-			// If the File contained any valid token.Pos values,
-			// they would all be invalid wrt the new token.File,
-			// but we have established that it lacks FileStart,
-			// Package, and Name.Pos.
-			file.FileStart = token.Pos(tok.Base())
-			file.FileEnd = token.Pos(tok.Base() + tok.Size())
-		}
-		return tok
+		return fset.File(file.FileStart)
 	}
 
 	tok := tokenFile(file)