1// Copyright 2020 The Go Authors. All rights reserved. 2// Use of this source code is governed by a BSD-style 3// license that can be found in the LICENSE file. 4 5package fake 6 7import ( 8 "bytes" 9 "context" 10 "crypto/sha256" 11 "fmt" 12 "io/ioutil" 13 "os" 14 "path/filepath" 15 "strings" 16 "sync" 17 18 "golang.org/x/tools/internal/lsp/protocol" 19 "golang.org/x/tools/internal/span" 20 errors "golang.org/x/xerrors" 21) 22 23// FileEvent wraps the protocol.FileEvent so that it can be associated with a 24// workdir-relative path. 25type FileEvent struct { 26 Path, Content string 27 ProtocolEvent protocol.FileEvent 28} 29 30// RelativeTo is a helper for operations relative to a given directory. 31type RelativeTo string 32 33// AbsPath returns an absolute filesystem path for the workdir-relative path. 34func (r RelativeTo) AbsPath(path string) string { 35 fp := filepath.FromSlash(path) 36 if filepath.IsAbs(fp) { 37 return fp 38 } 39 return filepath.Join(string(r), filepath.FromSlash(path)) 40} 41 42// RelPath returns a '/'-encoded path relative to the working directory (or an 43// absolute path if the file is outside of workdir) 44func (r RelativeTo) RelPath(fp string) string { 45 root := string(r) 46 if rel, err := filepath.Rel(root, fp); err == nil && !strings.HasPrefix(rel, "..") { 47 return filepath.ToSlash(rel) 48 } 49 return filepath.ToSlash(fp) 50} 51 52func writeTxtar(txt string, rel RelativeTo) error { 53 files := unpackTxt(txt) 54 for name, data := range files { 55 if err := WriteFileData(name, data, rel); err != nil { 56 return errors.Errorf("writing to workdir: %w", err) 57 } 58 } 59 return nil 60} 61 62// WriteFileData writes content to the relative path, replacing the special 63// token $SANDBOX_WORKDIR with the relative root given by rel. 64func WriteFileData(path string, content []byte, rel RelativeTo) error { 65 content = bytes.ReplaceAll(content, []byte("$SANDBOX_WORKDIR"), []byte(rel)) 66 fp := rel.AbsPath(path) 67 if err := os.MkdirAll(filepath.Dir(fp), 0755); err != nil { 68 return errors.Errorf("creating nested directory: %w", err) 69 } 70 if err := ioutil.WriteFile(fp, []byte(content), 0644); err != nil { 71 return errors.Errorf("writing %q: %w", path, err) 72 } 73 return nil 74} 75 76// Workdir is a temporary working directory for tests. It exposes file 77// operations in terms of relative paths, and fakes file watching by triggering 78// events on file operations. 79type Workdir struct { 80 RelativeTo 81 82 watcherMu sync.Mutex 83 watchers []func(context.Context, []FileEvent) 84 85 fileMu sync.Mutex 86 files map[string]string 87} 88 89// NewWorkdir writes the txtar-encoded file data in txt to dir, and returns a 90// Workir for operating on these files using 91func NewWorkdir(dir string) *Workdir { 92 return &Workdir{RelativeTo: RelativeTo(dir)} 93} 94 95func hashFile(data []byte) string { 96 return fmt.Sprintf("%x", sha256.Sum256(data)) 97} 98 99func (w *Workdir) writeInitialFiles(txt string) error { 100 files := unpackTxt(txt) 101 w.files = map[string]string{} 102 for name, data := range files { 103 w.files[name] = hashFile(data) 104 if err := WriteFileData(name, data, w.RelativeTo); err != nil { 105 return errors.Errorf("writing to workdir: %w", err) 106 } 107 } 108 return nil 109} 110 111// RootURI returns the root URI for this working directory of this scratch 112// environment. 113func (w *Workdir) RootURI() protocol.DocumentURI { 114 return toURI(string(w.RelativeTo)) 115} 116 117// AddWatcher registers the given func to be called on any file change. 118func (w *Workdir) AddWatcher(watcher func(context.Context, []FileEvent)) { 119 w.watcherMu.Lock() 120 w.watchers = append(w.watchers, watcher) 121 w.watcherMu.Unlock() 122} 123 124// URI returns the URI to a the workdir-relative path. 125func (w *Workdir) URI(path string) protocol.DocumentURI { 126 return toURI(w.AbsPath(path)) 127} 128 129// URIToPath converts a uri to a workdir-relative path (or an absolute path, 130// if the uri is outside of the workdir). 131func (w *Workdir) URIToPath(uri protocol.DocumentURI) string { 132 fp := uri.SpanURI().Filename() 133 return w.RelPath(fp) 134} 135 136func toURI(fp string) protocol.DocumentURI { 137 return protocol.DocumentURI(span.URIFromPath(fp)) 138} 139 140// ReadFile reads a text file specified by a workdir-relative path. 141func (w *Workdir) ReadFile(path string) (string, error) { 142 b, err := ioutil.ReadFile(w.AbsPath(path)) 143 if err != nil { 144 return "", err 145 } 146 return string(b), nil 147} 148 149func (w *Workdir) RegexpRange(path, re string) (Pos, Pos, error) { 150 content, err := w.ReadFile(path) 151 if err != nil { 152 return Pos{}, Pos{}, err 153 } 154 return regexpRange(content, re) 155} 156 157// RegexpSearch searches the file corresponding to path for the first position 158// matching re. 159func (w *Workdir) RegexpSearch(path string, re string) (Pos, error) { 160 content, err := w.ReadFile(path) 161 if err != nil { 162 return Pos{}, err 163 } 164 start, _, err := regexpRange(content, re) 165 return start, err 166} 167 168// ChangeFilesOnDisk executes the given on-disk file changes in a batch, 169// simulating the action of changing branches outside of an editor. 170func (w *Workdir) ChangeFilesOnDisk(ctx context.Context, events []FileEvent) error { 171 for _, e := range events { 172 switch e.ProtocolEvent.Type { 173 case protocol.Deleted: 174 fp := w.AbsPath(e.Path) 175 if err := os.Remove(fp); err != nil { 176 return errors.Errorf("removing %q: %w", e.Path, err) 177 } 178 case protocol.Changed, protocol.Created: 179 if _, err := w.writeFile(ctx, e.Path, e.Content); err != nil { 180 return err 181 } 182 } 183 } 184 w.sendEvents(ctx, events) 185 return nil 186} 187 188// RemoveFile removes a workdir-relative file path. 189func (w *Workdir) RemoveFile(ctx context.Context, path string) error { 190 fp := w.AbsPath(path) 191 if err := os.RemoveAll(fp); err != nil { 192 return errors.Errorf("removing %q: %w", path, err) 193 } 194 evts := []FileEvent{{ 195 Path: path, 196 ProtocolEvent: protocol.FileEvent{ 197 URI: w.URI(path), 198 Type: protocol.Deleted, 199 }, 200 }} 201 w.sendEvents(ctx, evts) 202 return nil 203} 204 205func (w *Workdir) sendEvents(ctx context.Context, evts []FileEvent) { 206 if len(evts) == 0 { 207 return 208 } 209 w.watcherMu.Lock() 210 watchers := make([]func(context.Context, []FileEvent), len(w.watchers)) 211 copy(watchers, w.watchers) 212 w.watcherMu.Unlock() 213 for _, w := range watchers { 214 go w(ctx, evts) 215 } 216} 217 218// WriteFiles writes the text file content to workdir-relative paths. 219// It batches notifications rather than sending them consecutively. 220func (w *Workdir) WriteFiles(ctx context.Context, files map[string]string) error { 221 var evts []FileEvent 222 for filename, content := range files { 223 evt, err := w.writeFile(ctx, filename, content) 224 if err != nil { 225 return err 226 } 227 evts = append(evts, evt) 228 } 229 w.sendEvents(ctx, evts) 230 return nil 231} 232 233// WriteFile writes text file content to a workdir-relative path. 234func (w *Workdir) WriteFile(ctx context.Context, path, content string) error { 235 evt, err := w.writeFile(ctx, path, content) 236 if err != nil { 237 return err 238 } 239 w.sendEvents(ctx, []FileEvent{evt}) 240 return nil 241} 242 243func (w *Workdir) writeFile(ctx context.Context, path, content string) (FileEvent, error) { 244 fp := w.AbsPath(path) 245 _, err := os.Stat(fp) 246 if err != nil && !os.IsNotExist(err) { 247 return FileEvent{}, errors.Errorf("checking if %q exists: %w", path, err) 248 } 249 var changeType protocol.FileChangeType 250 if os.IsNotExist(err) { 251 changeType = protocol.Created 252 } else { 253 changeType = protocol.Changed 254 } 255 if err := WriteFileData(path, []byte(content), w.RelativeTo); err != nil { 256 return FileEvent{}, err 257 } 258 return FileEvent{ 259 Path: path, 260 ProtocolEvent: protocol.FileEvent{ 261 URI: w.URI(path), 262 Type: changeType, 263 }, 264 }, nil 265} 266 267// listFiles lists files in the given directory, returning a map of relative 268// path to modification time. 269func (w *Workdir) listFiles(dir string) (map[string]string, error) { 270 files := make(map[string]string) 271 absDir := w.AbsPath(dir) 272 if err := filepath.Walk(absDir, func(fp string, info os.FileInfo, err error) error { 273 if err != nil { 274 return err 275 } 276 if info.IsDir() { 277 return nil 278 } 279 path := w.RelPath(fp) 280 data, err := ioutil.ReadFile(fp) 281 if err != nil { 282 return err 283 } 284 files[path] = hashFile(data) 285 return nil 286 }); err != nil { 287 return nil, err 288 } 289 return files, nil 290} 291 292// CheckForFileChanges walks the working directory and checks for any files 293// that have changed since the last poll. 294func (w *Workdir) CheckForFileChanges(ctx context.Context) error { 295 evts, err := w.pollFiles() 296 if err != nil { 297 return err 298 } 299 w.sendEvents(ctx, evts) 300 return nil 301} 302 303// pollFiles updates w.files and calculates FileEvents corresponding to file 304// state changes since the last poll. It does not call sendEvents. 305func (w *Workdir) pollFiles() ([]FileEvent, error) { 306 w.fileMu.Lock() 307 defer w.fileMu.Unlock() 308 309 files, err := w.listFiles(".") 310 if err != nil { 311 return nil, err 312 } 313 var evts []FileEvent 314 // Check which files have been added or modified. 315 for path, hash := range files { 316 oldhash, ok := w.files[path] 317 delete(w.files, path) 318 var typ protocol.FileChangeType 319 switch { 320 case !ok: 321 typ = protocol.Created 322 case oldhash != hash: 323 typ = protocol.Changed 324 default: 325 continue 326 } 327 evts = append(evts, FileEvent{ 328 Path: path, 329 ProtocolEvent: protocol.FileEvent{ 330 URI: w.URI(path), 331 Type: typ, 332 }, 333 }) 334 } 335 // Any remaining files must have been deleted. 336 for path := range w.files { 337 evts = append(evts, FileEvent{ 338 Path: path, 339 ProtocolEvent: protocol.FileEvent{ 340 URI: w.URI(path), 341 Type: protocol.Deleted, 342 }, 343 }) 344 } 345 w.files = files 346 return evts, nil 347} 348