clerk/journal/lexer/lexer.go (view raw)
| 1 | package lexer |
| 2 | |
| 3 | import ( |
| 4 | "strings" |
| 5 | "unicode" |
| 6 | "unicode/utf8" |
| 7 | |
| 8 | "olexsmir.xyz/clerk/journal/token" |
| 9 | ) |
| 10 | |
| 11 | type Mode uint |
| 12 | |
| 13 | const ( |
| 14 | // start of a line, nothing consumed |
| 15 | ModeDefault Mode = iota |
| 16 | |
| 17 | // after ; # * % ; at start of line, or anywhere inline |
| 18 | // everything until \n is comment text |
| 19 | ModeComment |
| 20 | |
| 21 | // after lexing a date at column 0 |
| 22 | // expects: optional status, optional code, description, comment |
| 23 | ModeTransaction |
| 24 | |
| 25 | // after lexing an indent at start of line |
| 26 | // expects: account name, then two spaces, then amount |
| 27 | ModePosting |
| 28 | |
| 29 | // after ~, period expression |
| 30 | // expects: period, optional description (after 2+ spaces), optional comment |
| 31 | ModePeriodic |
| 32 | |
| 33 | // after =, automates transaction |
| 34 | // expects: expression |
| 35 | ModeAutomated |
| 36 | |
| 37 | // after a directive keyword like account, commodity, include |
| 38 | // expects: rest of directive content |
| 39 | ModeDirective |
| 40 | ) |
| 41 | |
| 42 | type Lexer struct { |
| 43 | file string |
| 44 | input []byte |
| 45 | mode Mode |
| 46 | |
| 47 | ch rune // current rune (0 = EOF/sentinel) |
| 48 | chSize int // byte size of current rune |
| 49 | pos int // current byte offset (points at ch) |
| 50 | rpos int // next byte offset to read (one ahead of pos) |
| 51 | col int // current column (1-based) |
| 52 | line int // current line (1-based) |
| 53 | |
| 54 | transactionPastStatus bool |
| 55 | postingExpectAccount bool |
| 56 | } |
| 57 | |
| 58 | func New(file string, input []byte) *Lexer { |
| 59 | l := &Lexer{ |
| 60 | file: file, |
| 61 | input: input, |
| 62 | line: 1, |
| 63 | } |
| 64 | l.advance() |
| 65 | if l.ch == '\uFEFF' { // start of the input |
| 66 | l.advance() |
| 67 | } |
| 68 | return l |
| 69 | } |
| 70 | |
| 71 | // Next returns next token in the input |
| 72 | func (l *Lexer) Next() token.Token { |
| 73 | switch l.mode { |
| 74 | case ModeDefault: |
| 75 | return l.lexDefault() |
| 76 | case ModeComment: |
| 77 | return l.lexComment() |
| 78 | case ModeTransaction: |
| 79 | return l.lexTransaction() |
| 80 | case ModePosting: |
| 81 | return l.lexPosting() |
| 82 | case ModePeriodic: |
| 83 | return l.lexPeriodic() |
| 84 | case ModeAutomated: |
| 85 | return l.lexAutomated() |
| 86 | case ModeDirective: |
| 87 | return l.lexDirective() |
| 88 | } |
| 89 | panic("unreachable") |
| 90 | } |
| 91 | |
| 92 | func (l *Lexer) lexDefault() token.Token { |
| 93 | switch { |
| 94 | case l.ch == 0: |
| 95 | return l.token(token.EOF, "") |
| 96 | case l.ch == '\n': |
| 97 | return l.lexNewline() |
| 98 | case l.ch == '\r': |
| 99 | l.col = 0 |
| 100 | l.advance() |
| 101 | return l.lexNewline() |
| 102 | case l.ch == ' ' || l.ch == '\t': |
| 103 | tok := l.lexIndent() |
| 104 | l.mode = ModePosting |
| 105 | l.postingExpectAccount = true |
| 106 | return tok |
| 107 | case l.ch == ';' || l.ch == '#' || l.ch == '%': |
| 108 | l.mode = ModeComment |
| 109 | return l.lexSingle(token.SEMICOLON) // todo: ?? |
| 110 | case l.ch == '*': // * at col 0 == comment |
| 111 | l.mode = ModeComment |
| 112 | return l.lexSingle(token.STAR) |
| 113 | case l.ch == '~': |
| 114 | l.mode = ModePeriodic |
| 115 | return l.lexSingle(token.TILDE) |
| 116 | case l.ch == '=': |
| 117 | l.mode = ModeAutomated |
| 118 | return l.lexSingle(token.EQ) |
| 119 | case l.ch == '+': |
| 120 | return l.lexSingle(token.PLUS) |
| 121 | case l.ch == '-': |
| 122 | return l.lexSingle(token.MINUS) |
| 123 | case l.ch == '.': |
| 124 | return l.lexSingle(token.TEXT) |
| 125 | case l.ch == '!': |
| 126 | return l.lexSingle(token.BANG) |
| 127 | case l.ch == '@': |
| 128 | return l.lexSingle(token.AT) |
| 129 | case l.isAlpha(): |
| 130 | return l.lexKeyword() |
| 131 | case l.isDigit(): |
| 132 | if !l.isDate() { |
| 133 | s := l.save() |
| 134 | for l.isDigit() || l.ch == '-' || l.ch == '/' || l.ch == '.' { |
| 135 | l.advance() |
| 136 | } |
| 137 | return token.Token{Type: token.ILLEGAL, Literal: string(l.input[s.offset:l.pos]), Span: l.span(s)} |
| 138 | } |
| 139 | tok := l.lexDate() |
| 140 | l.mode = ModeTransaction |
| 141 | l.transactionPastStatus = false |
| 142 | return tok |
| 143 | default: |
| 144 | s := l.save() |
| 145 | l.advance() |
| 146 | return token.Token{Type: token.ILLEGAL, Literal: string(l.input[s.offset:l.pos]), Span: l.span(s)} |
| 147 | } |
| 148 | } |
| 149 | |
| 150 | func (l *Lexer) lexComment() token.Token { |
| 151 | if l.ch == '\n' || l.ch == 0 { |
| 152 | l.mode = ModeDefault |
| 153 | return l.lexNewline() |
| 154 | } |
| 155 | |
| 156 | for l.ch == ' ' || l.ch == '\t' { |
| 157 | l.lexWhitespace() |
| 158 | } |
| 159 | |
| 160 | if l.ch == '\n' || l.ch == 0 { |
| 161 | l.mode = ModeDefault |
| 162 | return l.lexNewline() |
| 163 | } |
| 164 | |
| 165 | s := l.save() |
| 166 | for l.ch != '\n' && l.ch != 0 { |
| 167 | l.advance() |
| 168 | } |
| 169 | return token.Token{Type: token.TEXT, Literal: string(l.input[s.offset:l.pos]), Span: l.span(s)} |
| 170 | } |
| 171 | |
| 172 | func (l *Lexer) lexTransaction() token.Token { |
| 173 | switch l.ch { |
| 174 | case 0: |
| 175 | return l.token(token.EOF, "") |
| 176 | case '\n': |
| 177 | l.mode = ModeDefault |
| 178 | return l.lexNewline() |
| 179 | case '\r': |
| 180 | l.col = 0 |
| 181 | l.advance() |
| 182 | return l.lexNewline() |
| 183 | case ';': |
| 184 | l.mode = ModeComment |
| 185 | return l.lexSingle(token.SEMICOLON) |
| 186 | case ' ', '\t': |
| 187 | return l.lexWhitespace() |
| 188 | case '*': |
| 189 | if !l.transactionPastStatus { |
| 190 | l.transactionPastStatus = true |
| 191 | return l.lexSingle(token.STAR) |
| 192 | } |
| 193 | return l.lexText() |
| 194 | case '!': |
| 195 | if !l.transactionPastStatus { |
| 196 | l.transactionPastStatus = true |
| 197 | return l.lexSingle(token.BANG) |
| 198 | } |
| 199 | return l.lexText() |
| 200 | case '|': |
| 201 | return l.lexSingle(token.PIPE) |
| 202 | case '+': |
| 203 | return l.lexSingle(token.PLUS) |
| 204 | case '-': |
| 205 | return l.lexSingle(token.MINUS) |
| 206 | case '=': |
| 207 | return l.lexEquals() |
| 208 | case '"', '\'': |
| 209 | return l.lexString() |
| 210 | default: // description / payee |
| 211 | if l.isDate() { // secondsry date after = |
| 212 | return l.lexDate() |
| 213 | } |
| 214 | return l.lexText() |
| 215 | } |
| 216 | } |
| 217 | |
| 218 | func (l *Lexer) lexPeriodic() token.Token { |
| 219 | switch l.ch { |
| 220 | case 0: |
| 221 | return l.token(token.EOF, "") |
| 222 | case '\n': |
| 223 | l.mode = ModeDefault |
| 224 | return l.lexNewline() |
| 225 | case '\r': |
| 226 | l.col = 0 |
| 227 | l.advance() |
| 228 | return l.lexNewline() |
| 229 | case ';': |
| 230 | l.mode = ModeComment |
| 231 | return l.lexSingle(token.SEMICOLON) |
| 232 | case ' ', '\t': |
| 233 | return l.lexWhitespace() |
| 234 | default: |
| 235 | return l.lexText() |
| 236 | } |
| 237 | } |
| 238 | |
| 239 | func (l *Lexer) lexAutomated() token.Token { |
| 240 | switch l.ch { |
| 241 | case 0: |
| 242 | return l.token(token.EOF, "") |
| 243 | case '\n': |
| 244 | l.mode = ModeDefault |
| 245 | return l.lexNewline() |
| 246 | case '\r': |
| 247 | l.col = 0 |
| 248 | l.advance() |
| 249 | return l.lexNewline() |
| 250 | case ' ', '\t': |
| 251 | return l.lexWhitespace() |
| 252 | case ';': |
| 253 | l.mode = ModeComment |
| 254 | return l.lexSingle(token.SEMICOLON) |
| 255 | default: |
| 256 | return l.lexText() |
| 257 | } |
| 258 | } |
| 259 | |
| 260 | func (l *Lexer) lexPosting() token.Token { |
| 261 | switch { |
| 262 | case l.ch == 0: |
| 263 | l.postingExpectAccount = false |
| 264 | return l.token(token.EOF, "") |
| 265 | case l.ch == '\n': |
| 266 | l.postingExpectAccount = false |
| 267 | l.mode = ModeDefault |
| 268 | return l.lexNewline() |
| 269 | case l.ch == ';': |
| 270 | l.postingExpectAccount = false |
| 271 | l.mode = ModeComment |
| 272 | return l.lexSingle(token.SEMICOLON) |
| 273 | case l.ch == ' ' || l.ch == '\t': |
| 274 | return l.lexWhitespace() |
| 275 | case l.postingExpectAccount && l.ch == '*': |
| 276 | return l.lexSingle(token.STAR) |
| 277 | case l.postingExpectAccount && l.ch == '!': |
| 278 | return l.lexSingle(token.BANG) |
| 279 | case l.ch == '=': |
| 280 | return l.lexEquals() |
| 281 | case l.ch == '@': |
| 282 | return l.lexAt() |
| 283 | case l.ch == '{': |
| 284 | return l.lexLBrace() |
| 285 | case l.ch == '}': |
| 286 | return l.lexRBrace() |
| 287 | case l.ch == '(': |
| 288 | if !l.postingExpectAccount { |
| 289 | return l.lexParenExpr() |
| 290 | } |
| 291 | return l.lexSingle(token.LPAREN) |
| 292 | case l.ch == ')': |
| 293 | return l.lexSingle(token.RPAREN) |
| 294 | case l.ch == '[': |
| 295 | return l.lexSingle(token.LBRACKET) |
| 296 | case l.ch == ']': |
| 297 | return l.lexSingle(token.RBRACKET) |
| 298 | case l.postingExpectAccount && l.ch != '*' && l.ch != '!' && l.ch != '(' && l.ch != '[': |
| 299 | l.postingExpectAccount = false |
| 300 | return l.lexAccountText() |
| 301 | case l.ch == '*': // after account name |
| 302 | return l.lexSingle(token.STAR) |
| 303 | case l.isDigit(), l.ch == '.': |
| 304 | return l.lexNumber() |
| 305 | case l.ch == '-': |
| 306 | return l.lexSingle(token.MINUS) |
| 307 | case l.ch == '+': |
| 308 | return l.lexSingle(token.PLUS) |
| 309 | case l.isCommodityStart(): |
| 310 | return l.lexCommodityMark() |
| 311 | case l.ch >= 'a' && l.ch <= 'z': |
| 312 | return l.lexCommodityMark() |
| 313 | default: |
| 314 | return l.lexAccountText() |
| 315 | } |
| 316 | } |
| 317 | |
| 318 | func (l *Lexer) lexDirective() token.Token { |
| 319 | switch l.ch { |
| 320 | case '\n', 0: |
| 321 | l.mode = ModeDefault |
| 322 | return l.lexNewline() |
| 323 | case ';': |
| 324 | l.mode = ModeComment |
| 325 | return l.lexSingle(token.SEMICOLON) |
| 326 | case ' ', '\t': |
| 327 | return l.lexWhitespace() |
| 328 | case '=': |
| 329 | return l.lexSingle(token.EQ) |
| 330 | case '+': |
| 331 | return l.lexSingle(token.PLUS) |
| 332 | case '-': |
| 333 | return l.lexSingle(token.MINUS) |
| 334 | case '.': |
| 335 | return l.lexSingle(token.TEXT) |
| 336 | case '"', '\'': |
| 337 | return l.lexString() |
| 338 | default: |
| 339 | if l.isCommodityStart() { |
| 340 | return l.lexCommodityMark() |
| 341 | } |
| 342 | if l.isTime() { |
| 343 | return l.lexTime() |
| 344 | } |
| 345 | if l.isDate() { |
| 346 | return l.lexDate() |
| 347 | } |
| 348 | if l.isDigit() { |
| 349 | return l.lexNumber() |
| 350 | } |
| 351 | return l.lexText() |
| 352 | } |
| 353 | // case l.ch == '/': // regex in 'alias' |
| 354 | // return l.lexSingle(token.SLASH) |
| 355 | } |
| 356 | |
| 357 | func (l *Lexer) lexSingle(kind token.Type) token.Token { |
| 358 | s := l.save() |
| 359 | l.advance() |
| 360 | return token.Token{ |
| 361 | Type: kind, |
| 362 | Literal: string(l.input[s.offset:l.pos]), |
| 363 | Span: l.span(s), |
| 364 | } |
| 365 | } |
| 366 | |
| 367 | func (l *Lexer) lexNewline() token.Token { |
| 368 | s := l.save() |
| 369 | l.advance() |
| 370 | l.mode = ModeDefault |
| 371 | return token.Token{Type: token.NEWLINE, Literal: "\n", Span: l.span(s)} |
| 372 | } |
| 373 | |
| 374 | func (l *Lexer) lexWhitespace() token.Token { |
| 375 | s := l.save() |
| 376 | for l.ch == ' ' || l.ch == '\t' { |
| 377 | l.advance() |
| 378 | } |
| 379 | lit := string(l.input[s.offset:l.pos]) |
| 380 | return token.Token{Type: token.WHITESPACE, Literal: lit, Span: l.span(s)} |
| 381 | } |
| 382 | |
| 383 | func (l *Lexer) lexIndent() token.Token { |
| 384 | s := l.save() |
| 385 | for l.ch == ' ' || l.ch == '\t' { |
| 386 | l.advance() |
| 387 | } |
| 388 | lit := string(l.input[s.offset:l.pos]) |
| 389 | return token.Token{Type: token.INDENT, Literal: lit, Span: l.span(s)} |
| 390 | } |
| 391 | |
| 392 | func (l *Lexer) lexEquals() token.Token { |
| 393 | s := l.save() |
| 394 | l.advance() |
| 395 | if l.ch == '=' { |
| 396 | l.advance() |
| 397 | switch l.ch { |
| 398 | case '=': |
| 399 | l.advance() |
| 400 | return token.Token{Type: token.EQEQEQ, Literal: "===", Span: l.span(s)} |
| 401 | case '*': |
| 402 | l.advance() |
| 403 | return token.Token{Type: token.EQEQEQ, Literal: "==*", Span: l.span(s)} |
| 404 | default: |
| 405 | return token.Token{Type: token.EQEQ, Literal: "==", Span: l.span(s)} |
| 406 | } |
| 407 | } |
| 408 | return token.Token{Type: token.EQ, Literal: "=", Span: l.span(s)} |
| 409 | } |
| 410 | |
| 411 | func (l *Lexer) lexAt() token.Token { |
| 412 | s := l.save() |
| 413 | l.advance() |
| 414 | if l.ch == '@' { |
| 415 | l.advance() |
| 416 | return token.Token{Type: token.ATAT, Literal: "@@", Span: l.span(s)} |
| 417 | } |
| 418 | return token.Token{Type: token.AT, Literal: "@", Span: l.span(s)} |
| 419 | } |
| 420 | |
| 421 | func (l *Lexer) lexText() token.Token { |
| 422 | s := l.save() |
| 423 | l.advance() |
| 424 | for l.ch != '\n' && l.ch != ';' && l.ch != 0 && l.ch != ' ' && l.ch != '\t' { |
| 425 | l.advance() |
| 426 | } |
| 427 | lit := string(l.input[s.offset:l.pos]) |
| 428 | return token.Token{Type: token.TEXT, Literal: lit, Span: l.span(s)} |
| 429 | } |
| 430 | |
| 431 | func (l *Lexer) lexAccountText() token.Token { |
| 432 | s := l.save() |
| 433 | for l.ch != '\n' && l.ch != ';' && l.ch != 0 && l.ch != ')' && l.ch != ']' { |
| 434 | // two spaces = end of account name |
| 435 | if l.isTwoSpaces() { |
| 436 | break |
| 437 | } |
| 438 | l.advance() |
| 439 | } |
| 440 | lit := string(l.input[s.offset:l.pos]) |
| 441 | return token.Token{Type: token.TEXT, Literal: lit, Span: l.span(s)} |
| 442 | } |
| 443 | |
| 444 | func (l *Lexer) lexParenExpr() token.Token { |
| 445 | s := l.save() |
| 446 | depth := 0 |
| 447 | for l.ch != '\n' && l.ch != 0 { |
| 448 | if l.ch == '(' { |
| 449 | depth++ |
| 450 | } else if l.ch == ')' { |
| 451 | depth-- |
| 452 | if depth == 0 { |
| 453 | l.advance() |
| 454 | break |
| 455 | } |
| 456 | } |
| 457 | l.advance() |
| 458 | } |
| 459 | lit := string(l.input[s.offset:l.pos]) |
| 460 | return token.Token{Type: token.PARENEXPR, Literal: lit, Span: l.span(s)} |
| 461 | } |
| 462 | |
| 463 | func (l *Lexer) lexNumber() token.Token { |
| 464 | s := l.save() |
| 465 | for { |
| 466 | if l.isDigit() || l.ch == '.' || l.ch == ',' || l.ch == '_' || l.ch == '\'' { |
| 467 | l.advance() |
| 468 | } else if l.ch == ' ' && (l.peek() >= '0' && l.peek() <= '9') { |
| 469 | l.advance() |
| 470 | } else { |
| 471 | break |
| 472 | } |
| 473 | } |
| 474 | lit := string(l.input[s.offset:l.pos]) |
| 475 | kind := token.INT |
| 476 | if strings.ContainsAny(lit, "., ") { |
| 477 | kind = token.DECIMAL |
| 478 | } |
| 479 | return token.Token{Type: kind, Literal: lit, Span: l.span(s)} |
| 480 | } |
| 481 | |
| 482 | func (l *Lexer) lexKeyword() token.Token { |
| 483 | s := l.save() |
| 484 | for l.ch != 0 && l.ch != '\n' && l.ch != '\r' && l.ch != ' ' && l.ch != '\t' && l.ch != ';' { |
| 485 | l.advance() |
| 486 | } |
| 487 | lit := string(l.input[s.offset:l.pos]) |
| 488 | kind := l.keyword(lit) |
| 489 | if kind == token.ILLEGAL { // todo: report an error ?? |
| 490 | kind = token.TEXT |
| 491 | } else { |
| 492 | l.mode = ModeDirective |
| 493 | } |
| 494 | return token.Token{Type: kind, Literal: lit, Span: l.span(s)} |
| 495 | } |
| 496 | |
| 497 | func (l *Lexer) lexDate() token.Token { |
| 498 | s := l.save() |
| 499 | for l.isDigit() || (l.isDateSep() && l.peekIsDigit()) { |
| 500 | l.advance() |
| 501 | } |
| 502 | return token.Token{Type: token.DATE, Literal: string(l.input[s.offset:l.pos]), Span: l.span(s)} |
| 503 | } |
| 504 | |
| 505 | func isSymbolChar(r rune) bool { |
| 506 | return r == '$' || unicode.In(r, unicode.Sc) |
| 507 | } |
| 508 | |
| 509 | func (l *Lexer) lexString() token.Token { |
| 510 | s := l.save() |
| 511 | quote := l.ch |
| 512 | l.advance() // consume the quote character |
| 513 | for l.ch != quote && l.ch != '\n' && l.ch != 0 { |
| 514 | l.advance() |
| 515 | } |
| 516 | if l.ch == quote { |
| 517 | l.advance() |
| 518 | } |
| 519 | return token.Token{Type: token.STRING, Literal: string(l.input[s.offset:l.pos]), Span: l.span(s)} |
| 520 | } |
| 521 | |
| 522 | func (l *Lexer) lexCommodityMark() token.Token { |
| 523 | s := l.save() |
| 524 | |
| 525 | if l.ch == '"' { |
| 526 | l.advance() |
| 527 | for l.ch != '"' && l.ch != '\n' && l.ch != 0 { |
| 528 | l.advance() |
| 529 | } |
| 530 | if l.ch == '"' { |
| 531 | l.advance() |
| 532 | } |
| 533 | return token.Token{Type: token.COMMODITYMARK, Literal: string(l.input[s.offset:l.pos]), Span: l.span(s)} |
| 534 | } |
| 535 | |
| 536 | if unicode.IsLetter(l.ch) { |
| 537 | for unicode.IsLetter(l.ch) || unicode.IsDigit(l.ch) { |
| 538 | l.advance() |
| 539 | } |
| 540 | return token.Token{Type: token.COMMODITYMARK, Literal: string(l.input[s.offset:l.pos]), Span: l.span(s)} |
| 541 | } |
| 542 | |
| 543 | if isSymbolChar(l.ch) { |
| 544 | for isSymbolChar(l.ch) { |
| 545 | l.advance() |
| 546 | } |
| 547 | return token.Token{Type: token.COMMODITYMARK, Literal: string(l.input[s.offset:l.pos]), Span: l.span(s)} |
| 548 | } |
| 549 | |
| 550 | l.advance() |
| 551 | return token.Token{Type: token.COMMODITYMARK, Literal: string(l.input[s.offset:l.pos]), Span: l.span(s)} |
| 552 | } |
| 553 | |
| 554 | func (l *Lexer) lexLBrace() token.Token { |
| 555 | s := l.save() |
| 556 | l.advance() |
| 557 | if l.ch == '{' { |
| 558 | l.advance() |
| 559 | return token.Token{Type: token.LBRACELBRACE, Literal: "{{", Span: l.span(s)} |
| 560 | } |
| 561 | return token.Token{Type: token.LBRACE, Literal: "{", Span: l.span(s)} |
| 562 | } |
| 563 | |
| 564 | func (l *Lexer) lexRBrace() token.Token { |
| 565 | s := l.save() |
| 566 | l.advance() |
| 567 | if l.ch == '}' { |
| 568 | l.advance() |
| 569 | return token.Token{Type: token.RBRACERBRACE, Literal: "}}", Span: l.span(s)} |
| 570 | } |
| 571 | return token.Token{Type: token.RBRACE, Literal: "}", Span: l.span(s)} |
| 572 | } |
| 573 | |
| 574 | func (l *Lexer) advance() { |
| 575 | if l.rpos >= len(l.input) { |
| 576 | l.ch = 0 |
| 577 | l.chSize = 0 |
| 578 | } else { |
| 579 | r, size := utf8.DecodeRune(l.input[l.rpos:]) |
| 580 | l.ch = r |
| 581 | l.chSize = size |
| 582 | } |
| 583 | l.pos = l.rpos |
| 584 | l.rpos += l.chSize |
| 585 | if l.ch == '\n' || l.ch == '\r' { |
| 586 | l.line++ |
| 587 | l.col = 0 |
| 588 | } else { |
| 589 | l.col++ |
| 590 | } |
| 591 | } |
| 592 | |
| 593 | func (l *Lexer) peek() rune { |
| 594 | r, _ := utf8.DecodeRune(l.input[l.rpos:]) |
| 595 | return r |
| 596 | } |
| 597 | |
| 598 | func (l *Lexer) peekN(n int) byte { |
| 599 | if l.pos+n >= len(l.input) { |
| 600 | return 0 |
| 601 | } |
| 602 | return l.input[l.pos+n] |
| 603 | } |
| 604 | |
| 605 | func (l *Lexer) isDigit() bool { return l.ch >= '0' && l.ch <= '9' } |
| 606 | func (l *Lexer) isAlpha() bool { |
| 607 | return (l.ch >= 'a' && l.ch <= 'z') || |
| 608 | (l.ch >= 'A' && l.ch <= 'Z') |
| 609 | } |
| 610 | |
| 611 | func (l *Lexer) isTwoSpaces() bool { return l.ch == ' ' && l.peek() == ' ' } |
| 612 | |
| 613 | func (l *Lexer) isDateSep() bool { return l.ch == '-' || l.ch == '/' || l.ch == '.' } |
| 614 | |
| 615 | func (l *Lexer) peekIsDigit() bool { |
| 616 | r := l.peek() |
| 617 | return r >= '0' && r <= '9' |
| 618 | } |
| 619 | |
| 620 | func (l *Lexer) isCommodityStart() bool { |
| 621 | if l.ch == '$' || (l.ch >= 'A' && l.ch <= 'Z') { |
| 622 | return true |
| 623 | } |
| 624 | if l.ch < utf8.RuneSelf { |
| 625 | return false |
| 626 | } |
| 627 | return unicode.In(l.ch, unicode.Sc) || unicode.IsLetter(l.ch) |
| 628 | } |
| 629 | |
| 630 | func (l *Lexer) isDate() bool { |
| 631 | if !l.isDigit() { |
| 632 | return false |
| 633 | } |
| 634 | // YYYY/M/D or YYYY/MM/DD |
| 635 | if l.peekN(1) >= '0' && l.peekN(1) <= '9' && |
| 636 | l.peekN(2) >= '0' && l.peekN(2) <= '9' && |
| 637 | l.peekN(3) >= '0' && l.peekN(3) <= '9' { |
| 638 | sep := l.peekN(4) |
| 639 | if sep == '/' || sep == '-' || sep == '.' { |
| 640 | if l.peekN(5) >= '0' && l.peekN(5) <= '9' { |
| 641 | if l.peekN(6) == sep { |
| 642 | return l.peekN(7) >= '0' && l.peekN(7) <= '9' |
| 643 | } |
| 644 | if l.peekN(7) == sep { |
| 645 | return l.peekN(8) >= '0' && l.peekN(8) <= '9' |
| 646 | } |
| 647 | } |
| 648 | } |
| 649 | return false |
| 650 | } |
| 651 | // M/D or MM/DD(year inferred, only / and - separators; . is ambiguous with decimal numbers like 1.01) |
| 652 | if (l.peekN(1) == '/' || l.peekN(1) == '-') && |
| 653 | l.peekN(2) >= '0' && l.peekN(2) <= '9' && |
| 654 | l.ch >= '1' && l.ch <= '9' { |
| 655 | return validDay(l.peekN(2), l.peekN(3)) |
| 656 | } |
| 657 | if (l.peekN(2) == '/' || l.peekN(2) == '-') && |
| 658 | l.peekN(3) >= '0' && l.peekN(3) <= '9' { |
| 659 | m := int(l.ch-'0')*10 + int(l.peekN(1)-'0') |
| 660 | return m >= 1 && m <= 12 && validDay(l.peekN(3), l.peekN(4)) |
| 661 | } |
| 662 | return false |
| 663 | } |
| 664 | |
| 665 | func validDay(first, second byte) bool { |
| 666 | d := int(first - '0') |
| 667 | if second >= '0' && second <= '9' { |
| 668 | d = d*10 + int(second-'0') |
| 669 | } |
| 670 | return d >= 1 && d <= 31 |
| 671 | } |
| 672 | |
| 673 | func (l *Lexer) isTime() bool { |
| 674 | if !l.isDigit() { |
| 675 | return false |
| 676 | } |
| 677 | return l.peekN(2) == ':' |
| 678 | } |
| 679 | |
| 680 | func (l *Lexer) lexTime() token.Token { |
| 681 | s := l.save() |
| 682 | for l.isDigit() || l.ch == ':' { |
| 683 | l.advance() |
| 684 | } |
| 685 | return token.Token{Type: token.TIME, Literal: string(l.input[s.offset:l.pos]), Span: l.span(s)} |
| 686 | } |
| 687 | |
| 688 | type savedPos struct{ offset, line, col int } |
| 689 | |
| 690 | func (l *Lexer) save() savedPos { |
| 691 | return savedPos{l.pos, l.line, l.col} |
| 692 | } |
| 693 | |
| 694 | func (l *Lexer) span(s savedPos) token.Span { |
| 695 | return token.Span{ |
| 696 | Start: token.Pos{File: l.file, Offset: s.offset, Line: s.line, Col: s.col}, |
| 697 | End: token.Pos{File: l.file, Offset: l.pos, Line: l.line, Col: l.col}, |
| 698 | } |
| 699 | } |
| 700 | |
| 701 | func (l *Lexer) token(kind token.Type, literal string) token.Token { |
| 702 | s := savedPos{l.pos, l.line, l.col} |
| 703 | return token.Token{Type: kind, Literal: literal, Span: l.span(s)} |
| 704 | } |
| 705 | |
| 706 | func (l *Lexer) keyword(s string) token.Type { |
| 707 | switch s { |
| 708 | case "comment": |
| 709 | return token.COMMENTKW |
| 710 | case "account": |
| 711 | return token.ACCOUNT |
| 712 | case "commodity": |
| 713 | return token.COMMODITY |
| 714 | case "include": |
| 715 | return token.INCLUDE |
| 716 | case "alias": |
| 717 | return token.ALIAS |
| 718 | case "payee": |
| 719 | return token.PAYEE |
| 720 | case "tag": |
| 721 | return token.TAG |
| 722 | case "apply": |
| 723 | return token.APPLY |
| 724 | case "end": |
| 725 | return token.END |
| 726 | case "Y", "year": |
| 727 | return token.YEAR |
| 728 | case "decimal-mark": |
| 729 | return token.DECIMALMARK |
| 730 | case "D": |
| 731 | return token.D |
| 732 | case "P": |
| 733 | return token.P |
| 734 | case "N": |
| 735 | return token.N |
| 736 | case "C": |
| 737 | return token.C |
| 738 | default: |
| 739 | return token.ILLEGAL |
| 740 | } |
| 741 | } |