Build with Go 1.20 and update misc dependencies

Signed-off-by: Alex Ellis (OpenFaaS Ltd) <alexellis2@gmail.com>

vendor/golang.org/x/tools/internal/gcimporter/iexport.go

@@ -44,12 +44,12 @@ func IExportShallow(fset *token.FileSet, pkg *types.Package) ([]byte, error) {
 	return out.Bytes(), err
 }
 
-// IImportShallow decodes "shallow" types.Package data encoded by IExportShallow
-// in the same executable. This function cannot import data from
+// IImportShallow decodes "shallow" types.Package data encoded by
+// IExportShallow in the same executable. This function cannot import data from
 // cmd/compile or gcexportdata.Write.
-func IImportShallow(fset *token.FileSet, imports map[string]*types.Package, data []byte, path string, insert InsertType) (*types.Package, error) {
+func IImportShallow(fset *token.FileSet, getPackage GetPackageFunc, data []byte, path string, insert InsertType) (*types.Package, error) {
 	const bundle = false
-	pkgs, err := iimportCommon(fset, imports, data, bundle, path, insert)
+	pkgs, err := iimportCommon(fset, getPackage, data, bundle, path, insert)
 	if err != nil {
 		return nil, err
 	}

vendor/golang.org/x/tools/internal/gcimporter/iimport.go

@@ -85,7 +85,7 @@ const (
 // If the export data version is not recognized or the format is otherwise
 // compromised, an error is returned.
 func IImportData(fset *token.FileSet, imports map[string]*types.Package, data []byte, path string) (int, *types.Package, error) {
-	pkgs, err := iimportCommon(fset, imports, data, false, path, nil)
+	pkgs, err := iimportCommon(fset, GetPackageFromMap(imports), data, false, path, nil)
 	if err != nil {
 		return 0, nil, err
 	}
@@ -94,10 +94,33 @@ func IImportData(fset *token.FileSet, imports map[string]*types.Package, data []
 
 // IImportBundle imports a set of packages from the serialized package bundle.
 func IImportBundle(fset *token.FileSet, imports map[string]*types.Package, data []byte) ([]*types.Package, error) {
-	return iimportCommon(fset, imports, data, true, "", nil)
+	return iimportCommon(fset, GetPackageFromMap(imports), data, true, "", nil)
 }
 
-func iimportCommon(fset *token.FileSet, imports map[string]*types.Package, data []byte, bundle bool, path string, insert InsertType) (pkgs []*types.Package, err error) {
+// A GetPackageFunc is a function that gets the package with the given path
+// from the importer state, creating it (with the specified name) if necessary.
+// It is an abstraction of the map historically used to memoize package creation.
+//
+// Two calls with the same path must return the same package.
+//
+// If the given getPackage func returns nil, the import will fail.
+type GetPackageFunc = func(path, name string) *types.Package
+
+// GetPackageFromMap returns a GetPackageFunc that retrieves packages from the
+// given map of package path -> package.
+//
+// The resulting func may mutate m: if a requested package is not found, a new
+// package will be inserted into m.
+func GetPackageFromMap(m map[string]*types.Package) GetPackageFunc {
+	return func(path, name string) *types.Package {
+		if _, ok := m[path]; !ok {
+			m[path] = types.NewPackage(path, name)
+		}
+		return m[path]
+	}
+}
+
+func iimportCommon(fset *token.FileSet, getPackage GetPackageFunc, data []byte, bundle bool, path string, insert InsertType) (pkgs []*types.Package, err error) {
 	const currentVersion = iexportVersionCurrent
 	version := int64(-1)
 	if !debug {
@@ -195,10 +218,9 @@ func iimportCommon(fset *token.FileSet, imports map[string]*types.Package, data
 		if pkgPath == "" {
 			pkgPath = path
 		}
-		pkg := imports[pkgPath]
+		pkg := getPackage(pkgPath, pkgName)
 		if pkg == nil {
-			pkg = types.NewPackage(pkgPath, pkgName)
-			imports[pkgPath] = pkg
+			errorf("internal error: getPackage returned nil package for %s", pkgPath)
 		} else if pkg.Name() != pkgName {
 			errorf("conflicting names %s and %s for package %q", pkg.Name(), pkgName, path)
 		}

vendor/golang.org/x/tools/internal/tokeninternal/tokeninternal.go

@@ -7,7 +7,9 @@
 package tokeninternal
 
 import (
+	"fmt"
 	"go/token"
+	"sort"
 	"sync"
 	"unsafe"
 )
@@ -57,3 +59,93 @@ func GetLines(file *token.File) []int {
 		panic("unexpected token.File size")
 	}
 }
+
+// AddExistingFiles adds the specified files to the FileSet if they
+// are not already present. It panics if any pair of files in the
+// resulting FileSet would overlap.
+func AddExistingFiles(fset *token.FileSet, files []*token.File) {
+	// Punch through the FileSet encapsulation.
+	type tokenFileSet struct {
+		// This type remained essentially consistent from go1.16 to go1.21.
+		mutex sync.RWMutex
+		base  int
+		files []*token.File
+		_     *token.File // changed to atomic.Pointer[token.File] in go1.19
+	}
+
+	// If the size of token.FileSet changes, this will fail to compile.
+	const delta = int64(unsafe.Sizeof(tokenFileSet{})) - int64(unsafe.Sizeof(token.FileSet{}))
+	var _ [-delta * delta]int
+
+	type uP = unsafe.Pointer
+	var ptr *tokenFileSet
+	*(*uP)(uP(&ptr)) = uP(fset)
+	ptr.mutex.Lock()
+	defer ptr.mutex.Unlock()
+
+	// Merge and sort.
+	newFiles := append(ptr.files, files...)
+	sort.Slice(newFiles, func(i, j int) bool {
+		return newFiles[i].Base() < newFiles[j].Base()
+	})
+
+	// Reject overlapping files.
+	// Discard adjacent identical files.
+	out := newFiles[:0]
+	for i, file := range newFiles {
+		if i > 0 {
+			prev := newFiles[i-1]
+			if file == prev {
+				continue
+			}
+			if prev.Base()+prev.Size()+1 > file.Base() {
+				panic(fmt.Sprintf("file %s (%d-%d) overlaps with file %s (%d-%d)",
+					prev.Name(), prev.Base(), prev.Base()+prev.Size(),
+					file.Name(), file.Base(), file.Base()+file.Size()))
+			}
+		}
+		out = append(out, file)
+	}
+	newFiles = out
+
+	ptr.files = newFiles
+
+	// Advance FileSet.Base().
+	if len(newFiles) > 0 {
+		last := newFiles[len(newFiles)-1]
+		newBase := last.Base() + last.Size() + 1
+		if ptr.base < newBase {
+			ptr.base = newBase
+		}
+	}
+}
+
+// FileSetFor returns a new FileSet containing a sequence of new Files with
+// the same base, size, and line as the input files, for use in APIs that
+// require a FileSet.
+//
+// Precondition: the input files must be non-overlapping, and sorted in order
+// of their Base.
+func FileSetFor(files ...*token.File) *token.FileSet {
+	fset := token.NewFileSet()
+	for _, f := range files {
+		f2 := fset.AddFile(f.Name(), f.Base(), f.Size())
+		lines := GetLines(f)
+		f2.SetLines(lines)
+	}
+	return fset
+}
+
+// CloneFileSet creates a new FileSet holding all files in fset. It does not
+// create copies of the token.Files in fset: they are added to the resulting
+// FileSet unmodified.
+func CloneFileSet(fset *token.FileSet) *token.FileSet {
+	var files []*token.File
+	fset.Iterate(func(f *token.File) bool {
+		files = append(files, f)
+		return true
+	})
+	newFileSet := token.NewFileSet()
+	AddExistingFiles(newFileSet, files)
+	return newFileSet
+}