| 🛟 Updated. 28d5985 k33g 16h ago | 1 | package buffer |
| 2 | |
| 3 | import ( |
| 4 | "errors" |
| 5 | "os" |
| 6 | "path/filepath" |
| 7 | "testing" |
| 8 | ) |
| 9 | |
| 10 | func TestOpenReadsTheFile(t *testing.T) { |
| 11 | path := filepath.Join(t.TempDir(), "main.go") |
| 12 | writeTestFile(t, path, "package main\n\nfunc main() {}\n") |
| 13 | |
| 14 | b, err := Open(path) |
| 15 | if err != nil { |
| 16 | t.Fatalf("Open() error = %v", err) |
| 17 | } |
| 18 | |
| 19 | if got := b.LineCount(); got != 3 { |
| 20 | t.Errorf("LineCount() = %d, want 3", got) |
| 21 | } |
| 22 | if got := b.Path(); got != path { |
| 23 | t.Errorf("Path() = %q, want %q", got, path) |
| 24 | } |
| 25 | if b.Modified() { |
| 26 | t.Error("a freshly opened buffer must not be modified") |
| 27 | } |
| 28 | if b.CanUndo() { |
| 29 | t.Error("opening a file must not leave anything to undo") |
| 30 | } |
| 31 | } |
| 32 | |
| 33 | func TestOpenAMissingFileGivesAnEmptyBuffer(t *testing.T) { |
| 34 | path := filepath.Join(t.TempDir(), "new.go") |
| 35 | |
| 36 | b, err := Open(path) |
| 37 | if err != nil { |
| 38 | t.Fatalf("Open() error = %v, want nil for a file that does not exist yet", err) |
| 39 | } |
| 40 | |
| 41 | if got := b.LineCount(); got != 1 { |
| 42 | t.Errorf("LineCount() = %d, want 1", got) |
| 43 | } |
| 44 | if got := b.Path(); got != path { |
| 45 | t.Errorf("Path() = %q, want the requested path", got) |
| 46 | } |
| 47 | if b.Modified() { |
| 48 | t.Error("an empty new buffer must not be modified") |
| 49 | } |
| 50 | } |
| 51 | |
| 52 | func TestOpenADirectoryFails(t *testing.T) { |
| 53 | if _, err := Open(t.TempDir()); err == nil { |
| 54 | t.Fatal("Open() error = nil, want a failure when the path is a directory") |
| 55 | } |
| 56 | } |
| 57 | |
| 58 | func TestSaveWritesTheTextBack(t *testing.T) { |
| 59 | path := filepath.Join(t.TempDir(), "main.go") |
| 60 | writeTestFile(t, path, "package main\n") |
| 61 | |
| 62 | b, err := Open(path) |
| 63 | if err != nil { |
| 64 | t.Fatalf("Open() error = %v", err) |
| 65 | } |
| 66 | b.MoveBufferEnd() |
| 67 | b.Insert("\nfunc main() {}") |
| 68 | |
| 69 | if err := b.Save(); err != nil { |
| 70 | t.Fatalf("Save() error = %v", err) |
| 71 | } |
| 72 | if b.Modified() { |
| 73 | t.Error("Save must clear the modified flag") |
| 74 | } |
| 75 | |
| 76 | want := "package main\nfunc main() {}\n" |
| 77 | if got := readTestFile(t, path); got != want { |
| 78 | t.Errorf("file content = %q, want %q", got, want) |
| 79 | } |
| 80 | } |
| 81 | |
| 82 | func TestSaveRoundTripsAnUnmodifiedFileByteForByte(t *testing.T) { |
| 83 | tests := []struct { |
| 84 | name string |
| 85 | content string |
| 86 | }{ |
| 87 | {"unix endings", "a\nb\n"}, |
| 88 | {"windows endings", "a\r\nb\r\n"}, |
| 89 | {"no trailing newline", "a\nb"}, |
| 90 | {"empty file", ""}, |
| 91 | } |
| 92 | |
| 93 | for _, tc := range tests { |
| 94 | t.Run(tc.name, func(t *testing.T) { |
| 95 | path := filepath.Join(t.TempDir(), "f.txt") |
| 96 | writeTestFile(t, path, tc.content) |
| 97 | |
| 98 | b, err := Open(path) |
| 99 | if err != nil { |
| 100 | t.Fatalf("Open() error = %v", err) |
| 101 | } |
| 102 | if err := b.Save(); err != nil { |
| 103 | t.Fatalf("Save() error = %v", err) |
| 104 | } |
| 105 | |
| 106 | if got := readTestFile(t, path); got != tc.content { |
| 107 | t.Errorf("file content = %q, want %q", got, tc.content) |
| 108 | } |
| 109 | }) |
| 110 | } |
| 111 | } |
| 112 | |
| 113 | func TestSaveWithoutAPathReportsErrNoPath(t *testing.T) { |
| 114 | b := NewFromString("orphan") |
| 115 | |
| 116 | err := b.Save() |
| 117 | |
| 118 | if !errors.Is(err, ErrNoPath) { |
| 119 | t.Errorf("Save() error = %v, want ErrNoPath", err) |
| 120 | } |
| 121 | } |
| 122 | |
| 123 | func TestSaveAsAdoptsTheNewPath(t *testing.T) { |
| 124 | dir := t.TempDir() |
| 125 | path := filepath.Join(dir, "copy.go") |
| 126 | b := NewFromString("package main\n") |
| 127 | |
| 128 | if err := b.SaveAs(path); err != nil { |
| 129 | t.Fatalf("SaveAs() error = %v", err) |
| 130 | } |
| 131 | |
| 132 | if got := b.Path(); got != path { |
| 133 | t.Errorf("Path() = %q, want %q", got, path) |
| 134 | } |
| 135 | if got := readTestFile(t, path); got != "package main\n" { |
| 136 | t.Errorf("file content = %q", got) |
| 137 | } |
| 138 | if entries, _ := os.ReadDir(dir); len(entries) != 1 { |
| 139 | t.Errorf("the directory holds %d entries, want 1 — the temporary file must be gone", len(entries)) |
| 140 | } |
| 141 | } |
| 142 | |
| 143 | func TestSaveKeepsTheExistingFilePermissions(t *testing.T) { |
| 144 | path := filepath.Join(t.TempDir(), "script.go") |
| 145 | writeTestFile(t, path, "package main\n") |
| 146 | if err := os.Chmod(path, 0o640); err != nil { |
| 147 | t.Fatalf("Chmod() error = %v", err) |
| 148 | } |
| 149 | |
| 150 | b, err := Open(path) |
| 151 | if err != nil { |
| 152 | t.Fatalf("Open() error = %v", err) |
| 153 | } |
| 154 | if err := b.Save(); err != nil { |
| 155 | t.Fatalf("Save() error = %v", err) |
| 156 | } |
| 157 | |
| 158 | info, err := os.Stat(path) |
| 159 | if err != nil { |
| 160 | t.Fatalf("Stat() error = %v", err) |
| 161 | } |
| 162 | if got := info.Mode().Perm(); got != 0o640 { |
| 163 | t.Errorf("permissions = %o, want 640 — the atomic rename must not tighten them", got) |
| 164 | } |
| 165 | } |
| 166 | |
| 167 | func TestSaveIntoAMissingDirectoryFails(t *testing.T) { |
| 168 | b := NewFromString("x") |
| 169 | |
| 170 | err := b.SaveAs(filepath.Join(t.TempDir(), "nope", "f.go")) |
| 171 | |
| 172 | if err == nil { |
| 173 | t.Fatal("SaveAs() error = nil, want a failure when the directory does not exist") |
| 174 | } |
| 175 | if b.Path() != "" { |
| 176 | t.Errorf("Path() = %q, want it left alone after a failed save", b.Path()) |
| 177 | } |
| 178 | } |
| 179 | |
| 180 | func TestModeOfFallsBackForAMissingFile(t *testing.T) { |
| 181 | if got := modeOf(filepath.Join(t.TempDir(), "absent")); got != defaultFileMode { |
| 182 | t.Errorf("modeOf(missing) = %o, want %o", got, defaultFileMode) |
| 183 | } |
| 184 | } |
| 185 | |
| 186 | // writeTestFile creates a file with the given content, failing the test if it |
| 187 | // cannot. |
| 188 | func writeTestFile(t *testing.T, path, content string) { |
| 189 | t.Helper() |
| 190 | if err := os.WriteFile(path, []byte(content), 0o644); err != nil { |
| 191 | t.Fatalf("writing %s: %v", path, err) |
| 192 | } |
| 193 | } |
| 194 | |
| 195 | // readTestFile returns the content of a file, failing the test if it cannot. |
| 196 | func readTestFile(t *testing.T, path string) string { |
| 197 | t.Helper() |
| 198 | data, err := os.ReadFile(path) |
| 199 | if err != nil { |
| 200 | t.Fatalf("reading %s: %v", path, err) |
| 201 | } |
| 202 | return string(data) |
| 203 | } |
| 204 | |
| 205 | func TestReloadPicksUpAChangeMadeOnDisk(t *testing.T) { |
| 206 | // What a formatter run from the Go menu leaves behind. |
| 207 | path := filepath.Join(t.TempDir(), "main.go") |
| 208 | writeTestFile(t, path, "package main\n") |
| 209 | b, err := Open(path) |
| 210 | if err != nil { |
| 211 | t.Fatalf("Open() error = %v", err) |
| 212 | } |
| 213 | |
| 214 | writeTestFile(t, path, "package main\n\nfunc main() {}\n") |
| 215 | changed, err := b.Reload() |
| 216 | |
| 217 | if err != nil { |
| 218 | t.Fatalf("Reload() error = %v", err) |
| 219 | } |
| 220 | if !changed { |
| 221 | t.Error("Reload() reported no change for a file that was rewritten") |
| 222 | } |
| 223 | if got := b.Text(); got != "package main\n\nfunc main() {}\n" { |
| 224 | t.Errorf("the buffer holds %q", got) |
| 225 | } |
| 226 | if b.Modified() { |
| 227 | t.Error("a reloaded buffer reports itself modified") |
| 228 | } |
| 229 | } |
| 230 | |
| 231 | func TestReloadReportsNoChangeWhenTheFileIsTheSame(t *testing.T) { |
| 232 | // A caller uses this to tell a file something rewrote from one it did not. |
| 233 | path := filepath.Join(t.TempDir(), "main.go") |
| 234 | writeTestFile(t, path, "package main\n") |
| 235 | b, _ := Open(path) |
| 236 | |
| 237 | changed, err := b.Reload() |
| 238 | |
| 239 | if err != nil { |
| 240 | t.Fatalf("Reload() error = %v", err) |
| 241 | } |
| 242 | if changed { |
| 243 | t.Error("Reload() reported a change for a file nobody touched") |
| 244 | } |
| 245 | } |
| 246 | |
| 247 | func TestReloadRefusesToThrowAwayUnsavedWork(t *testing.T) { |
| 248 | path := filepath.Join(t.TempDir(), "main.go") |
| 249 | writeTestFile(t, path, "package main\n") |
| 250 | b, _ := Open(path) |
| 251 | b.Insert("// mine") |
| 252 | before := b.Text() |
| 253 | |
| 254 | writeTestFile(t, path, "something else\n") |
| 255 | _, err := b.Reload() |
| 256 | |
| 257 | if !errors.Is(err, ErrModified) { |
| 258 | t.Fatalf("Reload() error = %v, want ErrModified", err) |
| 259 | } |
| 260 | if got := b.Text(); got != before { |
| 261 | t.Errorf("the buffer was reloaded anyway: %q", got) |
| 262 | } |
| 263 | } |
| 264 | |
| 265 | func TestReloadKeepsTheCursorWhereItWas(t *testing.T) { |
| 266 | // A formatter moves lines about; putting the cursor back at the top would |
| 267 | // lose the reader's place for no reason. |
| 268 | path := filepath.Join(t.TempDir(), "main.go") |
| 269 | writeTestFile(t, path, "one\ntwo\nthree\n") |
| 270 | b, _ := Open(path) |
| 271 | b.SetCursor(Position{Line: 1, Col: 2}) |
| 272 | |
| 273 | if _, err := b.Reload(); err != nil { |
| 274 | t.Fatalf("Reload() error = %v", err) |
| 275 | } |
| 276 | writeTestFile(t, path, "one\nTWO!\nthree\n") |
| 277 | if _, err := b.Reload(); err != nil { |
| 278 | t.Fatalf("Reload() error = %v", err) |
| 279 | } |
| 280 | |
| 281 | if got := b.Cursor(); got.Line != 1 || got.Col != 2 { |
| 282 | t.Errorf("Cursor() = %+v, want line 1 column 2", got) |
| 283 | } |
| 284 | } |
| 285 | |
| 286 | func TestReloadClampsACursorPastTheEndOfTheNewFile(t *testing.T) { |
| 287 | path := filepath.Join(t.TempDir(), "main.go") |
| 288 | writeTestFile(t, path, "one\ntwo\nthree\nfour\n") |
| 289 | b, _ := Open(path) |
| 290 | b.SetCursor(Position{Line: 3, Col: 4}) |
| 291 | |
| 292 | writeTestFile(t, path, "one\n") |
| 293 | if _, err := b.Reload(); err != nil { |
| 294 | t.Fatalf("Reload() error = %v", err) |
| 295 | } |
| 296 | |
| 297 | cursor := b.Cursor() |
| 298 | if cursor.Line >= b.LineCount() { |
| 299 | t.Errorf("Cursor() = %+v, past the end of a %d-line file", cursor, b.LineCount()) |
| 300 | } |
| 301 | } |
| 302 | |
| 303 | func TestReloadForgetsTheUndoHistory(t *testing.T) { |
| 304 | // Undoing back past a reload would restore text the file no longer has. |
| 305 | path := filepath.Join(t.TempDir(), "main.go") |
| 306 | writeTestFile(t, path, "one\n") |
| 307 | b, _ := Open(path) |
| 308 | b.Insert("x") |
| 309 | if err := b.Save(); err != nil { |
| 310 | t.Fatalf("Save() error = %v", err) |
| 311 | } |
| 312 | |
| 313 | writeTestFile(t, path, "reformatted\n") |
| 314 | if _, err := b.Reload(); err != nil { |
| 315 | t.Fatalf("Reload() error = %v", err) |
| 316 | } |
| 317 | b.Undo() |
| 318 | |
| 319 | if got := b.Text(); got != "reformatted\n" { |
| 320 | t.Errorf("undo after a reload gave %q", got) |
| 321 | } |
| 322 | } |
| 323 | |
| 324 | func TestReloadWithNoPathSaysSo(t *testing.T) { |
| 325 | if _, err := New().Reload(); !errors.Is(err, ErrNoPath) { |
| 326 | t.Errorf("Reload() error = %v, want ErrNoPath", err) |
| 327 | } |
| 328 | } |
| 329 | |
| 330 | func TestReloadOfAFileThatHasGoneIsAnError(t *testing.T) { |
| 331 | path := filepath.Join(t.TempDir(), "main.go") |
| 332 | writeTestFile(t, path, "package main\n") |
| 333 | b, _ := Open(path) |
| 334 | |
| 335 | if err := os.Remove(path); err != nil { |
| 336 | t.Fatalf("removing the file: %v", err) |
| 337 | } |
| 338 | if _, err := b.Reload(); err == nil { |
| 339 | t.Error("Reload() accepted a file that no longer exists") |
| 340 | } |
| 341 | } |