clang/unittests/Basic/CharInfoTest.cpp

   1 //===- unittests/Basic/CharInfoTest.cpp -- ASCII classification tests -----===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8
   9 #include "clang/Basic/CharInfo.h"
  10 #include "gtest/gtest.h"
  11
  12 using namespace llvm;
  13 using namespace clang;
  14
  15 // Check that the CharInfo table has been constructed reasonably.
  16 TEST(CharInfoTest, validateInfoTable) {
  17   using namespace charinfo;
  18   EXPECT_EQ((unsigned)CHAR_SPACE,   InfoTable[(unsigned)' ']);
  19   EXPECT_EQ((unsigned)CHAR_HORZ_WS, InfoTable[(unsigned)'\t']);
  20   EXPECT_EQ((unsigned)CHAR_HORZ_WS, InfoTable[(unsigned)'\f']); // ??
  21   EXPECT_EQ((unsigned)CHAR_HORZ_WS, InfoTable[(unsigned)'\v']); // ??
  22   EXPECT_EQ((unsigned)CHAR_VERT_WS, InfoTable[(unsigned)'\n']);
  23   EXPECT_EQ((unsigned)CHAR_VERT_WS, InfoTable[(unsigned)'\r']);
  24   EXPECT_EQ((unsigned)CHAR_UNDER,   InfoTable[(unsigned)'_']);
  25   EXPECT_EQ((unsigned)CHAR_PERIOD,  InfoTable[(unsigned)'.']);
  26
  27   for (unsigned i = 'a'; i <= 'f'; ++i) {
  28     EXPECT_EQ((unsigned)CHAR_XLOWER, InfoTable[i]);
  29     EXPECT_EQ((unsigned)CHAR_XUPPER, InfoTable[i+'A'-'a']);
  30   }
  31
  32   for (unsigned i = 'g'; i <= 'z'; ++i) {
  33     EXPECT_EQ((unsigned)CHAR_LOWER, InfoTable[i]);
  34     EXPECT_EQ((unsigned)CHAR_UPPER, InfoTable[i+'A'-'a']);
  35   }
  36
  37   for (unsigned i = '0'; i <= '9'; ++i)
  38     EXPECT_EQ((unsigned)CHAR_DIGIT, InfoTable[i]);
  39 }
  40
  41 // Check various predicates.
  42 TEST(CharInfoTest, isASCII) {
  43   EXPECT_TRUE(isASCII('\0'));
  44   EXPECT_TRUE(isASCII('\n'));
  45   EXPECT_TRUE(isASCII(' '));
  46   EXPECT_TRUE(isASCII('a'));
  47   EXPECT_TRUE(isASCII('\x7f'));
  48   EXPECT_FALSE(isASCII('\x80'));
  49   EXPECT_FALSE(isASCII('\xc2'));
  50   EXPECT_FALSE(isASCII('\xff'));
  51 }
  52
  53 TEST(CharInfoTest, isIdentifierHead) {
  54   EXPECT_TRUE(isIdentifierHead('a'));
  55   EXPECT_TRUE(isIdentifierHead('A'));
  56   EXPECT_TRUE(isIdentifierHead('z'));
  57   EXPECT_TRUE(isIdentifierHead('Z'));
  58   EXPECT_TRUE(isIdentifierHead('_'));
  59
  60   EXPECT_FALSE(isIdentifierHead('0'));
  61   EXPECT_FALSE(isIdentifierHead('.'));
  62   EXPECT_FALSE(isIdentifierHead('`'));
  63   EXPECT_FALSE(isIdentifierHead('\0'));
  64
  65   EXPECT_FALSE(isIdentifierHead('$'));
  66   EXPECT_TRUE(isIdentifierHead('$', /*AllowDollar=*/true));
  67
  68   EXPECT_FALSE(isIdentifierHead('\x80'));
  69   EXPECT_FALSE(isIdentifierHead('\xc2'));
  70   EXPECT_FALSE(isIdentifierHead('\xff'));
  71 }
  72
  73 TEST(CharInfoTest, isIdentifierBody) {
  74   EXPECT_TRUE(isIdentifierBody('a'));
  75   EXPECT_TRUE(isIdentifierBody('A'));
  76   EXPECT_TRUE(isIdentifierBody('z'));
  77   EXPECT_TRUE(isIdentifierBody('Z'));
  78   EXPECT_TRUE(isIdentifierBody('_'));
  79
  80   EXPECT_TRUE(isIdentifierBody('0'));
  81   EXPECT_FALSE(isIdentifierBody('.'));
  82   EXPECT_FALSE(isIdentifierBody('`'));
  83   EXPECT_FALSE(isIdentifierBody('\0'));
  84
  85   EXPECT_FALSE(isIdentifierBody('$'));
  86   EXPECT_TRUE(isIdentifierBody('$', /*AllowDollar=*/true));
  87
  88   EXPECT_FALSE(isIdentifierBody('\x80'));
  89   EXPECT_FALSE(isIdentifierBody('\xc2'));
  90   EXPECT_FALSE(isIdentifierBody('\xff'));
  91 }
  92
  93 TEST(CharInfoTest, isHorizontalWhitespace) {
  94   EXPECT_FALSE(isHorizontalWhitespace('a'));
  95   EXPECT_FALSE(isHorizontalWhitespace('_'));
  96   EXPECT_FALSE(isHorizontalWhitespace('0'));
  97   EXPECT_FALSE(isHorizontalWhitespace('.'));
  98   EXPECT_FALSE(isHorizontalWhitespace('`'));
  99   EXPECT_FALSE(isHorizontalWhitespace('\0'));
 100   EXPECT_FALSE(isHorizontalWhitespace('\x7f'));
 101
 102   EXPECT_TRUE(isHorizontalWhitespace(' '));
 103   EXPECT_TRUE(isHorizontalWhitespace('\t'));
 104   EXPECT_TRUE(isHorizontalWhitespace('\f')); // ??
 105   EXPECT_TRUE(isHorizontalWhitespace('\v')); // ??
 106
 107   EXPECT_FALSE(isHorizontalWhitespace('\n'));
 108   EXPECT_FALSE(isHorizontalWhitespace('\r'));
 109
 110   EXPECT_FALSE(isHorizontalWhitespace('\x80'));
 111   EXPECT_FALSE(isHorizontalWhitespace('\xc2'));
 112   EXPECT_FALSE(isHorizontalWhitespace('\xff'));
 113 }
 114
 115 TEST(CharInfoTest, isVerticalWhitespace) {
 116   EXPECT_FALSE(isVerticalWhitespace('a'));
 117   EXPECT_FALSE(isVerticalWhitespace('_'));
 118   EXPECT_FALSE(isVerticalWhitespace('0'));
 119   EXPECT_FALSE(isVerticalWhitespace('.'));
 120   EXPECT_FALSE(isVerticalWhitespace('`'));
 121   EXPECT_FALSE(isVerticalWhitespace('\0'));
 122   EXPECT_FALSE(isVerticalWhitespace('\x7f'));
 123
 124   EXPECT_FALSE(isVerticalWhitespace(' '));
 125   EXPECT_FALSE(isVerticalWhitespace('\t'));
 126   EXPECT_FALSE(isVerticalWhitespace('\f')); // ??
 127   EXPECT_FALSE(isVerticalWhitespace('\v')); // ??
 128
 129   EXPECT_TRUE(isVerticalWhitespace('\n'));
 130   EXPECT_TRUE(isVerticalWhitespace('\r'));
 131
 132   EXPECT_FALSE(isVerticalWhitespace('\x80'));
 133   EXPECT_FALSE(isVerticalWhitespace('\xc2'));
 134   EXPECT_FALSE(isVerticalWhitespace('\xff'));
 135 }
 136
 137 TEST(CharInfoTest, isWhitespace) {
 138   EXPECT_FALSE(isWhitespace('a'));
 139   EXPECT_FALSE(isWhitespace('_'));
 140   EXPECT_FALSE(isWhitespace('0'));
 141   EXPECT_FALSE(isWhitespace('.'));
 142   EXPECT_FALSE(isWhitespace('`'));
 143   EXPECT_FALSE(isWhitespace('\0'));
 144   EXPECT_FALSE(isWhitespace('\x7f'));
 145
 146   EXPECT_TRUE(isWhitespace(' '));
 147   EXPECT_TRUE(isWhitespace('\t'));
 148   EXPECT_TRUE(isWhitespace('\f'));
 149   EXPECT_TRUE(isWhitespace('\v'));
 150
 151   EXPECT_TRUE(isWhitespace('\n'));
 152   EXPECT_TRUE(isWhitespace('\r'));
 153
 154   EXPECT_FALSE(isWhitespace('\x80'));
 155   EXPECT_FALSE(isWhitespace('\xc2'));
 156   EXPECT_FALSE(isWhitespace('\xff'));
 157 }
 158
 159 TEST(CharInfoTest, isDigit) {
 160   EXPECT_TRUE(isDigit('0'));
 161   EXPECT_TRUE(isDigit('9'));
 162
 163   EXPECT_FALSE(isDigit('a'));
 164   EXPECT_FALSE(isDigit('A'));
 165
 166   EXPECT_FALSE(isDigit('z'));
 167   EXPECT_FALSE(isDigit('Z'));
 168
 169   EXPECT_FALSE(isDigit('.'));
 170   EXPECT_FALSE(isDigit('_'));
 171
 172   EXPECT_FALSE(isDigit('/'));
 173   EXPECT_FALSE(isDigit('\0'));
 174
 175   EXPECT_FALSE(isDigit('\x80'));
 176   EXPECT_FALSE(isDigit('\xc2'));
 177   EXPECT_FALSE(isDigit('\xff'));
 178 }
 179
 180 TEST(CharInfoTest, isHexDigit) {
 181   EXPECT_TRUE(isHexDigit('0'));
 182   EXPECT_TRUE(isHexDigit('9'));
 183
 184   EXPECT_TRUE(isHexDigit('a'));
 185   EXPECT_TRUE(isHexDigit('A'));
 186
 187   EXPECT_FALSE(isHexDigit('z'));
 188   EXPECT_FALSE(isHexDigit('Z'));
 189
 190   EXPECT_FALSE(isHexDigit('.'));
 191   EXPECT_FALSE(isHexDigit('_'));
 192
 193   EXPECT_FALSE(isHexDigit('/'));
 194   EXPECT_FALSE(isHexDigit('\0'));
 195
 196   EXPECT_FALSE(isHexDigit('\x80'));
 197   EXPECT_FALSE(isHexDigit('\xc2'));
 198   EXPECT_FALSE(isHexDigit('\xff'));
 199 }
 200
 201 TEST(CharInfoTest, isLetter) {
 202   EXPECT_FALSE(isLetter('0'));
 203   EXPECT_FALSE(isLetter('9'));
 204
 205   EXPECT_TRUE(isLetter('a'));
 206   EXPECT_TRUE(isLetter('A'));
 207
 208   EXPECT_TRUE(isLetter('z'));
 209   EXPECT_TRUE(isLetter('Z'));
 210
 211   EXPECT_FALSE(isLetter('.'));
 212   EXPECT_FALSE(isLetter('_'));
 213
 214   EXPECT_FALSE(isLetter('/'));
 215   EXPECT_FALSE(isLetter('('));
 216   EXPECT_FALSE(isLetter('\0'));
 217
 218   EXPECT_FALSE(isLetter('\x80'));
 219   EXPECT_FALSE(isLetter('\xc2'));
 220   EXPECT_FALSE(isLetter('\xff'));
 221 }
 222
 223 TEST(CharInfoTest, isLowercase) {
 224   EXPECT_FALSE(isLowercase('0'));
 225   EXPECT_FALSE(isLowercase('9'));
 226
 227   EXPECT_TRUE(isLowercase('a'));
 228   EXPECT_FALSE(isLowercase('A'));
 229
 230   EXPECT_TRUE(isLowercase('z'));
 231   EXPECT_FALSE(isLowercase('Z'));
 232
 233   EXPECT_FALSE(isLowercase('.'));
 234   EXPECT_FALSE(isLowercase('_'));
 235
 236   EXPECT_FALSE(isLowercase('/'));
 237   EXPECT_FALSE(isLowercase('('));
 238   EXPECT_FALSE(isLowercase('\0'));
 239
 240   EXPECT_FALSE(isLowercase('\x80'));
 241   EXPECT_FALSE(isLowercase('\xc2'));
 242   EXPECT_FALSE(isLowercase('\xff'));
 243 }
 244
 245 TEST(CharInfoTest, isUppercase) {
 246   EXPECT_FALSE(isUppercase('0'));
 247   EXPECT_FALSE(isUppercase('9'));
 248
 249   EXPECT_FALSE(isUppercase('a'));
 250   EXPECT_TRUE(isUppercase('A'));
 251
 252   EXPECT_FALSE(isUppercase('z'));
 253   EXPECT_TRUE(isUppercase('Z'));
 254
 255   EXPECT_FALSE(isUppercase('.'));
 256   EXPECT_FALSE(isUppercase('_'));
 257
 258   EXPECT_FALSE(isUppercase('/'));
 259   EXPECT_FALSE(isUppercase('('));
 260   EXPECT_FALSE(isUppercase('\0'));
 261
 262   EXPECT_FALSE(isUppercase('\x80'));
 263   EXPECT_FALSE(isUppercase('\xc2'));
 264   EXPECT_FALSE(isUppercase('\xff'));
 265 }
 266
 267 TEST(CharInfoTest, isAlphanumeric) {
 268   EXPECT_TRUE(isAlphanumeric('0'));
 269   EXPECT_TRUE(isAlphanumeric('9'));
 270
 271   EXPECT_TRUE(isAlphanumeric('a'));
 272   EXPECT_TRUE(isAlphanumeric('A'));
 273
 274   EXPECT_TRUE(isAlphanumeric('z'));
 275   EXPECT_TRUE(isAlphanumeric('Z'));
 276
 277   EXPECT_FALSE(isAlphanumeric('.'));
 278   EXPECT_FALSE(isAlphanumeric('_'));
 279
 280   EXPECT_FALSE(isAlphanumeric('/'));
 281   EXPECT_FALSE(isAlphanumeric('('));
 282   EXPECT_FALSE(isAlphanumeric('\0'));
 283
 284   EXPECT_FALSE(isAlphanumeric('\x80'));
 285   EXPECT_FALSE(isAlphanumeric('\xc2'));
 286   EXPECT_FALSE(isAlphanumeric('\xff'));
 287 }
 288
 289 TEST(CharInfoTest, isPunctuation) {
 290   EXPECT_FALSE(isPunctuation('0'));
 291   EXPECT_FALSE(isPunctuation('9'));
 292
 293   EXPECT_FALSE(isPunctuation('a'));
 294   EXPECT_FALSE(isPunctuation('A'));
 295
 296   EXPECT_FALSE(isPunctuation('z'));
 297   EXPECT_FALSE(isPunctuation('Z'));
 298
 299   EXPECT_TRUE(isPunctuation('.'));
 300   EXPECT_TRUE(isPunctuation('_'));
 301
 302   EXPECT_TRUE(isPunctuation('/'));
 303   EXPECT_TRUE(isPunctuation('('));
 304
 305   EXPECT_FALSE(isPunctuation(' '));
 306   EXPECT_FALSE(isPunctuation('\n'));
 307   EXPECT_FALSE(isPunctuation('\0'));
 308
 309   EXPECT_FALSE(isPunctuation('\x80'));
 310   EXPECT_FALSE(isPunctuation('\xc2'));
 311   EXPECT_FALSE(isPunctuation('\xff'));
 312 }
 313
 314 TEST(CharInfoTest, isPrintable) {
 315   EXPECT_TRUE(isPrintable('0'));
 316   EXPECT_TRUE(isPrintable('9'));
 317
 318   EXPECT_TRUE(isPrintable('a'));
 319   EXPECT_TRUE(isPrintable('A'));
 320
 321   EXPECT_TRUE(isPrintable('z'));
 322   EXPECT_TRUE(isPrintable('Z'));
 323
 324   EXPECT_TRUE(isPrintable('.'));
 325   EXPECT_TRUE(isPrintable('_'));
 326
 327   EXPECT_TRUE(isPrintable('/'));
 328   EXPECT_TRUE(isPrintable('('));
 329
 330   EXPECT_TRUE(isPrintable(' '));
 331   EXPECT_FALSE(isPrintable('\t'));
 332   EXPECT_FALSE(isPrintable('\n'));
 333   EXPECT_FALSE(isPrintable('\0'));
 334
 335   EXPECT_FALSE(isPrintable('\x80'));
 336   EXPECT_FALSE(isPrintable('\xc2'));
 337   EXPECT_FALSE(isPrintable('\xff'));
 338 }
 339
 340 TEST(CharInfoTest, isPreprocessingNumberBody) {
 341   EXPECT_TRUE(isPreprocessingNumberBody('0'));
 342   EXPECT_TRUE(isPreprocessingNumberBody('9'));
 343
 344   EXPECT_TRUE(isPreprocessingNumberBody('a'));
 345   EXPECT_TRUE(isPreprocessingNumberBody('A'));
 346
 347   EXPECT_TRUE(isPreprocessingNumberBody('z'));
 348   EXPECT_TRUE(isPreprocessingNumberBody('Z'));
 349   EXPECT_TRUE(isPreprocessingNumberBody('.'));
 350   EXPECT_TRUE(isPreprocessingNumberBody('_'));
 351
 352   EXPECT_FALSE(isPreprocessingNumberBody('/'));
 353   EXPECT_FALSE(isPreprocessingNumberBody('('));
 354   EXPECT_FALSE(isPreprocessingNumberBody('\0'));
 355
 356   EXPECT_FALSE(isPreprocessingNumberBody('\x80'));
 357   EXPECT_FALSE(isPreprocessingNumberBody('\xc2'));
 358   EXPECT_FALSE(isPreprocessingNumberBody('\xff'));
 359 }
 360
 361 TEST(CharInfoTest, isRawStringDelimBody) {
 362   EXPECT_TRUE(isRawStringDelimBody('0'));
 363   EXPECT_TRUE(isRawStringDelimBody('9'));
 364
 365   EXPECT_TRUE(isRawStringDelimBody('a'));
 366   EXPECT_TRUE(isRawStringDelimBody('A'));
 367
 368   EXPECT_TRUE(isRawStringDelimBody('z'));
 369   EXPECT_TRUE(isRawStringDelimBody('Z'));
 370   EXPECT_TRUE(isRawStringDelimBody('.'));
 371   EXPECT_TRUE(isRawStringDelimBody('_'));
 372
 373   EXPECT_TRUE(isRawStringDelimBody('/'));
 374   EXPECT_FALSE(isRawStringDelimBody('('));
 375   EXPECT_FALSE(isRawStringDelimBody('\0'));
 376
 377   EXPECT_FALSE(isRawStringDelimBody('\x80'));
 378   EXPECT_FALSE(isRawStringDelimBody('\xc2'));
 379   EXPECT_FALSE(isRawStringDelimBody('\xff'));
 380 }
 381
 382 TEST(CharInfoTest, toLowercase) {
 383   EXPECT_EQ('0', toLowercase('0'));
 384   EXPECT_EQ('9', toLowercase('9'));
 385
 386   EXPECT_EQ('a', toLowercase('a'));
 387   EXPECT_EQ('a', toLowercase('A'));
 388
 389   EXPECT_EQ('z', toLowercase('z'));
 390   EXPECT_EQ('z', toLowercase('Z'));
 391
 392   EXPECT_EQ('.', toLowercase('.'));
 393   EXPECT_EQ('_', toLowercase('_'));
 394
 395   EXPECT_EQ('/', toLowercase('/'));
 396   EXPECT_EQ('\0', toLowercase('\0'));
 397 }
 398
 399 TEST(CharInfoTest, toUppercase) {
 400   EXPECT_EQ('0', toUppercase('0'));
 401   EXPECT_EQ('9', toUppercase('9'));
 402
 403   EXPECT_EQ('A', toUppercase('a'));
 404   EXPECT_EQ('A', toUppercase('A'));
 405
 406   EXPECT_EQ('Z', toUppercase('z'));
 407   EXPECT_EQ('Z', toUppercase('Z'));
 408
 409   EXPECT_EQ('.', toUppercase('.'));
 410   EXPECT_EQ('_', toUppercase('_'));
 411
 412   EXPECT_EQ('/', toUppercase('/'));
 413   EXPECT_EQ('\0', toUppercase('\0'));
 414 }
 415
 416 TEST(CharInfoTest, isValidIdentifier) {
 417   EXPECT_FALSE(isValidIdentifier(""));
 418
 419   // 1 character
 420   EXPECT_FALSE(isValidIdentifier("."));
 421   EXPECT_FALSE(isValidIdentifier("\n"));
 422   EXPECT_FALSE(isValidIdentifier(" "));
 423   EXPECT_FALSE(isValidIdentifier("\x80"));
 424   EXPECT_FALSE(isValidIdentifier("\xc2"));
 425   EXPECT_FALSE(isValidIdentifier("\xff"));
 426   EXPECT_FALSE(isValidIdentifier("$"));
 427   EXPECT_FALSE(isValidIdentifier("1"));
 428
 429   EXPECT_TRUE(isValidIdentifier("_"));
 430   EXPECT_TRUE(isValidIdentifier("a"));
 431   EXPECT_TRUE(isValidIdentifier("z"));
 432   EXPECT_TRUE(isValidIdentifier("A"));
 433   EXPECT_TRUE(isValidIdentifier("Z"));
 434   EXPECT_TRUE(isValidIdentifier("$", /*AllowDollar=*/true));
 435
 436   // 2 characters, '_' suffix
 437   EXPECT_FALSE(isValidIdentifier("._"));
 438   EXPECT_FALSE(isValidIdentifier("\n_"));
 439   EXPECT_FALSE(isValidIdentifier(" _"));
 440   EXPECT_FALSE(isValidIdentifier("\x80_"));
 441   EXPECT_FALSE(isValidIdentifier("\xc2_"));
 442   EXPECT_FALSE(isValidIdentifier("\xff_"));
 443   EXPECT_FALSE(isValidIdentifier("$_"));
 444   EXPECT_FALSE(isValidIdentifier("1_"));
 445
 446   EXPECT_TRUE(isValidIdentifier("__"));
 447   EXPECT_TRUE(isValidIdentifier("a_"));
 448   EXPECT_TRUE(isValidIdentifier("z_"));
 449   EXPECT_TRUE(isValidIdentifier("A_"));
 450   EXPECT_TRUE(isValidIdentifier("Z_"));
 451   EXPECT_TRUE(isValidIdentifier("$_", /*AllowDollar=*/true));
 452
 453   // 2 characters, '_' prefix
 454   EXPECT_FALSE(isValidIdentifier("_."));
 455   EXPECT_FALSE(isValidIdentifier("_\n"));
 456   EXPECT_FALSE(isValidIdentifier("_ "));
 457   EXPECT_FALSE(isValidIdentifier("_\x80"));
 458   EXPECT_FALSE(isValidIdentifier("_\xc2"));
 459   EXPECT_FALSE(isValidIdentifier("_\xff"));
 460   EXPECT_FALSE(isValidIdentifier("_$"));
 461   EXPECT_TRUE(isValidIdentifier("_1"));
 462
 463   EXPECT_TRUE(isValidIdentifier("__"));
 464   EXPECT_TRUE(isValidIdentifier("_a"));
 465   EXPECT_TRUE(isValidIdentifier("_z"));
 466   EXPECT_TRUE(isValidIdentifier("_A"));
 467   EXPECT_TRUE(isValidIdentifier("_Z"));
 468   EXPECT_TRUE(isValidIdentifier("_$", /*AllowDollar=*/true));
 469
 470   // 3 characters, '__' prefix
 471   EXPECT_FALSE(isValidIdentifier("__."));
 472   EXPECT_FALSE(isValidIdentifier("__\n"));
 473   EXPECT_FALSE(isValidIdentifier("__ "));
 474   EXPECT_FALSE(isValidIdentifier("__\x80"));
 475   EXPECT_FALSE(isValidIdentifier("__\xc2"));
 476   EXPECT_FALSE(isValidIdentifier("__\xff"));
 477   EXPECT_FALSE(isValidIdentifier("__$"));
 478   EXPECT_TRUE(isValidIdentifier("__1"));
 479
 480   EXPECT_TRUE(isValidIdentifier("___"));
 481   EXPECT_TRUE(isValidIdentifier("__a"));
 482   EXPECT_TRUE(isValidIdentifier("__z"));
 483   EXPECT_TRUE(isValidIdentifier("__A"));
 484   EXPECT_TRUE(isValidIdentifier("__Z"));
 485   EXPECT_TRUE(isValidIdentifier("__$", /*AllowDollar=*/true));
 486
 487   // 3 characters, '_' prefix and suffix
 488   EXPECT_FALSE(isValidIdentifier("_._"));
 489   EXPECT_FALSE(isValidIdentifier("_\n_"));
 490   EXPECT_FALSE(isValidIdentifier("_ _"));
 491   EXPECT_FALSE(isValidIdentifier("_\x80_"));
 492   EXPECT_FALSE(isValidIdentifier("_\xc2_"));
 493   EXPECT_FALSE(isValidIdentifier("_\xff_"));
 494   EXPECT_FALSE(isValidIdentifier("_$_"));
 495   EXPECT_TRUE(isValidIdentifier("_1_"));
 496
 497   EXPECT_TRUE(isValidIdentifier("___"));
 498   EXPECT_TRUE(isValidIdentifier("_a_"));
 499   EXPECT_TRUE(isValidIdentifier("_z_"));
 500   EXPECT_TRUE(isValidIdentifier("_A_"));
 501   EXPECT_TRUE(isValidIdentifier("_Z_"));
 502   EXPECT_TRUE(isValidIdentifier("_$_", /*AllowDollar=*/true));
 503 }