| // Copyright 2022 Google LLC |
| // |
| // Licensed under the Apache License, Version 2.0 (the "License"); |
| // you may not use this file except in compliance with the License. |
| // You may obtain a copy of the License at |
| // |
| // http://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, software |
| // distributed under the License is distributed on an "AS IS" BASIS, |
| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| // See the License for the specific language governing permissions and |
| // limitations under the License. |
| |
| //go:build go1.18 |
| // +build go1.18 |
| |
| package aliasfix |
| |
| import ( |
| "bytes" |
| "go/ast" |
| "go/format" |
| "go/parser" |
| "go/token" |
| "io" |
| "io/fs" |
| "os" |
| "path/filepath" |
| "strconv" |
| "strings" |
| |
| "golang.org/x/tools/imports" |
| ) |
| |
| var ( |
| fset = token.NewFileSet() |
| ) |
| |
| // ProcessPath rewrites imports from go-genproto in terms of google-cloud-go |
| // types. |
| func ProcessPath(path string) error { |
| dir, err := os.Stat(path) |
| if err != nil { |
| return err |
| } |
| if dir.IsDir() { |
| err := filepath.WalkDir(path, func(path string, d fs.DirEntry, err error) error { |
| if err == nil && !d.IsDir() && strings.HasSuffix(d.Name(), ".go") { |
| err = processFile(path, nil) |
| } |
| if err != nil { |
| return err |
| } |
| return nil |
| }) |
| if err != nil { |
| return err |
| } |
| } else { |
| if err := processFile(path, nil); err != nil { |
| return err |
| } |
| } |
| return nil |
| } |
| |
| // processFile checks to see if the given file needs any imports rewritten and |
| // does so if needed. Note an io.Writer is injected here for testability. |
| func processFile(name string, w io.Writer) (err error) { |
| var f *ast.File |
| f, err = parser.ParseFile(fset, name, nil, parser.ParseComments) |
| if err != nil { |
| return err |
| } |
| var modified bool |
| for _, imp := range f.Imports { |
| var importPath string |
| importPath, err = strconv.Unquote(imp.Path.Value) |
| if err != nil { |
| return err |
| } |
| if pkg, ok := GenprotoPkgMigration[importPath]; ok && pkg.Status == StatusMigrated { |
| oldNamespace := importPath[strings.LastIndex(importPath, "/")+1:] |
| newNamespace := pkg.ImportPath[strings.LastIndex(pkg.ImportPath, "/")+1:] |
| if imp.Name == nil && oldNamespace != newNamespace { |
| // use old namespace for fewer diffs |
| imp.Name = ast.NewIdent(oldNamespace) |
| } else if imp.Name != nil && imp.Name.Name == newNamespace { |
| // no longer need named import if matching named import |
| imp.Name = nil |
| } |
| imp.EndPos = imp.End() |
| imp.Path.Value = strconv.Quote(pkg.ImportPath) |
| modified = true |
| } |
| } |
| if !modified { |
| return nil |
| } |
| |
| if w == nil { |
| backup := name + ".bak" |
| if err = os.Rename(name, backup); err != nil { |
| return err |
| } |
| defer func() { |
| if err != nil { |
| os.Rename(backup, name) |
| } else { |
| os.Remove(backup) |
| } |
| }() |
| var file *os.File |
| file, err = os.Create(name) |
| if err != nil { |
| return err |
| } |
| defer file.Close() |
| w = file |
| } |
| var buf bytes.Buffer |
| if err := format.Node(&buf, fset, f); err != nil { |
| return err |
| } |
| b, err := imports.Process(name, buf.Bytes(), nil) |
| if err != nil { |
| return err |
| } |
| if _, err := w.Write(b); err != nil { |
| return err |
| } |
| |
| return nil |
| } |