tests/test_hdl_ast.py

   1 import warnings
   2 from enum import Enum
   3
   4 from nmigen.hdl.ast import *
   5
   6 from .utils import *
   7
   8
   9 class UnsignedEnum(Enum):
  10     FOO = 1
  11     BAR = 2
  12     BAZ = 3
  13
  14
  15 class SignedEnum(Enum):
  16     FOO = -1
  17     BAR =  0
  18     BAZ = +1
  19
  20
  21 class StringEnum(Enum):
  22     FOO = "a"
  23     BAR = "b"
  24
  25
  26 class ShapeTestCase(FHDLTestCase):
  27     def test_make(self):
  28         s1 = Shape()
  29         self.assertEqual(s1.width, 1)
  30         self.assertEqual(s1.signed, False)
  31         s2 = Shape(signed=True)
  32         self.assertEqual(s2.width, 1)
  33         self.assertEqual(s2.signed, True)
  34         s3 = Shape(3, True)
  35         self.assertEqual(s3.width, 3)
  36         self.assertEqual(s3.signed, True)
  37
  38     def test_make_wrong(self):
  39         with self.assertRaisesRegex(TypeError,
  40                 r"^Width must be a non-negative integer, not -1$"):
  41             Shape(-1)
  42
  43     def test_compare_wrong(self):
  44         with self.assertRaisesRegex(TypeError,
  45                 r"^Shapes may be compared with other Shapes and \(int, bool\) tuples, not 'hi'$"):
  46             Shape(1, True) == 'hi'
  47
  48     def test_compare_tuple_wrong(self):
  49         with self.assertRaisesRegex(TypeError,
  50                 r"^Shapes may be compared with other Shapes and \(int, bool\) tuples, not \(2, 3\)$"):
  51             Shape(1, True) == (2, 3)
  52
  53     def test_repr(self):
  54         self.assertEqual(repr(Shape()), "unsigned(1)")
  55         self.assertEqual(repr(Shape(2, True)), "signed(2)")
  56
  57     def test_tuple(self):
  58         width, signed = Shape()
  59         self.assertEqual(width, 1)
  60         self.assertEqual(signed, False)
  61
  62     def test_unsigned(self):
  63         s1 = unsigned(2)
  64         self.assertIsInstance(s1, Shape)
  65         self.assertEqual(s1.width, 2)
  66         self.assertEqual(s1.signed, False)
  67
  68     def test_signed(self):
  69         s1 = signed(2)
  70         self.assertIsInstance(s1, Shape)
  71         self.assertEqual(s1.width, 2)
  72         self.assertEqual(s1.signed, True)
  73
  74     def test_cast_shape(self):
  75         s1 = Shape.cast(unsigned(1))
  76         self.assertEqual(s1.width, 1)
  77         self.assertEqual(s1.signed, False)
  78         s2 = Shape.cast(signed(3))
  79         self.assertEqual(s2.width, 3)
  80         self.assertEqual(s2.signed, True)
  81
  82     def test_cast_int(self):
  83         s1 = Shape.cast(2)
  84         self.assertEqual(s1.width, 2)
  85         self.assertEqual(s1.signed, False)
  86
  87     def test_cast_int_wrong(self):
  88         with self.assertRaisesRegex(TypeError,
  89                 r"^Width must be a non-negative integer, not -1$"):
  90             Shape.cast(-1)
  91
  92     def test_cast_tuple(self):
  93         with warnings.catch_warnings():
  94             warnings.filterwarnings(action="ignore", category=DeprecationWarning)
  95             s1 = Shape.cast((1, True))
  96             self.assertEqual(s1.width, 1)
  97             self.assertEqual(s1.signed, True)
  98
  99     def test_cast_tuple_wrong(self):
 100         with warnings.catch_warnings():
 101             warnings.filterwarnings(action="ignore", category=DeprecationWarning)
 102             with self.assertRaisesRegex(TypeError,
 103                     r"^Width must be a non-negative integer, not -1$"):
 104                 Shape.cast((-1, True))
 105
 106     def test_cast_range(self):
 107         s1 = Shape.cast(range(0, 8))
 108         self.assertEqual(s1.width, 3)
 109         self.assertEqual(s1.signed, False)
 110         s2 = Shape.cast(range(0, 9))
 111         self.assertEqual(s2.width, 4)
 112         self.assertEqual(s2.signed, False)
 113         s3 = Shape.cast(range(-7, 8))
 114         self.assertEqual(s3.width, 4)
 115         self.assertEqual(s3.signed, True)
 116         s4 = Shape.cast(range(0, 1))
 117         self.assertEqual(s4.width, 1)
 118         self.assertEqual(s4.signed, False)
 119         s5 = Shape.cast(range(-1, 0))
 120         self.assertEqual(s5.width, 1)
 121         self.assertEqual(s5.signed, True)
 122         s6 = Shape.cast(range(0, 0))
 123         self.assertEqual(s6.width, 0)
 124         self.assertEqual(s6.signed, False)
 125         s7 = Shape.cast(range(-1, -1))
 126         self.assertEqual(s7.width, 0)
 127         self.assertEqual(s7.signed, True)
 128
 129     def test_cast_enum(self):
 130         s1 = Shape.cast(UnsignedEnum)
 131         self.assertEqual(s1.width, 2)
 132         self.assertEqual(s1.signed, False)
 133         s2 = Shape.cast(SignedEnum)
 134         self.assertEqual(s2.width, 2)
 135         self.assertEqual(s2.signed, True)
 136
 137     def test_cast_enum_bad(self):
 138         with self.assertRaisesRegex(TypeError,
 139                 r"^Only enumerations with integer values can be used as value shapes$"):
 140             Shape.cast(StringEnum)
 141
 142     def test_cast_bad(self):
 143         with self.assertRaisesRegex(TypeError,
 144                 r"^Object 'foo' cannot be used as value shape$"):
 145             Shape.cast("foo")
 146
 147
 148 class ValueTestCase(FHDLTestCase):
 149     def test_cast(self):
 150         self.assertIsInstance(Value.cast(0), Const)
 151         self.assertIsInstance(Value.cast(True), Const)
 152         c = Const(0)
 153         self.assertIs(Value.cast(c), c)
 154         with self.assertRaisesRegex(TypeError,
 155                 r"^Object 'str' cannot be converted to an nMigen value$"):
 156             Value.cast("str")
 157
 158     def test_cast_enum(self):
 159         e1 = Value.cast(UnsignedEnum.FOO)
 160         self.assertIsInstance(e1, Const)
 161         self.assertEqual(e1.shape(), unsigned(2))
 162         e2 = Value.cast(SignedEnum.FOO)
 163         self.assertIsInstance(e2, Const)
 164         self.assertEqual(e2.shape(), signed(2))
 165
 166     def test_cast_enum_wrong(self):
 167         with self.assertRaisesRegex(TypeError,
 168                 r"^Only enumerations with integer values can be used as value shapes$"):
 169             Value.cast(StringEnum.FOO)
 170
 171     def test_bool(self):
 172         with self.assertRaisesRegex(TypeError,
 173                 r"^Attempted to convert nMigen value to Python boolean$"):
 174             if Const(0):
 175                 pass
 176
 177     def test_len(self):
 178         self.assertEqual(len(Const(10)), 4)
 179
 180     def test_getitem_int(self):
 181         s1 = Const(10)[0]
 182         self.assertIsInstance(s1, Slice)
 183         self.assertEqual(s1.start, 0)
 184         self.assertEqual(s1.stop, 1)
 185         s2 = Const(10)[-1]
 186         self.assertIsInstance(s2, Slice)
 187         self.assertEqual(s2.start, 3)
 188         self.assertEqual(s2.stop, 4)
 189         with self.assertRaisesRegex(IndexError,
 190                 r"^Index 5 is out of bounds for a 4-bit value$"):
 191             Const(10)[5]
 192
 193     def test_getitem_slice(self):
 194         s1 = Const(10)[1:3]
 195         self.assertIsInstance(s1, Slice)
 196         self.assertEqual(s1.start, 1)
 197         self.assertEqual(s1.stop, 3)
 198         s2 = Const(10)[1:-2]
 199         self.assertIsInstance(s2, Slice)
 200         self.assertEqual(s2.start, 1)
 201         self.assertEqual(s2.stop, 2)
 202         s3 = Const(31)[::2]
 203         self.assertIsInstance(s3, Cat)
 204         self.assertIsInstance(s3.parts[0], Slice)
 205         self.assertEqual(s3.parts[0].start, 0)
 206         self.assertEqual(s3.parts[0].stop, 1)
 207         self.assertIsInstance(s3.parts[1], Slice)
 208         self.assertEqual(s3.parts[1].start, 2)
 209         self.assertEqual(s3.parts[1].stop, 3)
 210         self.assertIsInstance(s3.parts[2], Slice)
 211         self.assertEqual(s3.parts[2].start, 4)
 212         self.assertEqual(s3.parts[2].stop, 5)
 213
 214     def test_getitem_wrong(self):
 215         with self.assertRaisesRegex(TypeError,
 216                 r"^Cannot index value with 'str'$"):
 217             Const(31)["str"]
 218
 219     def test_shift_left(self):
 220         self.assertRepr(Const(256, unsigned(9)).shift_left(0),
 221                         "(cat (const 0'd0) (const 9'd256))")
 222
 223         self.assertRepr(Const(256, unsigned(9)).shift_left(1),
 224                         "(cat (const 1'd0) (const 9'd256))")
 225         self.assertRepr(Const(256, unsigned(9)).shift_left(5),
 226                         "(cat (const 5'd0) (const 9'd256))")
 227         self.assertRepr(Const(256, signed(9)).shift_left(1),
 228                         "(s (cat (const 1'd0) (const 9'sd-256)))")
 229         self.assertRepr(Const(256, signed(9)).shift_left(5),
 230                         "(s (cat (const 5'd0) (const 9'sd-256)))")
 231
 232         self.assertRepr(Const(256, unsigned(9)).shift_left(-1),
 233                         "(slice (const 9'd256) 1:9)")
 234         self.assertRepr(Const(256, unsigned(9)).shift_left(-5),
 235                         "(slice (const 9'd256) 5:9)")
 236         self.assertRepr(Const(256, signed(9)).shift_left(-1),
 237                         "(s (slice (const 9'sd-256) 1:9))")
 238         self.assertRepr(Const(256, signed(9)).shift_left(-5),
 239                         "(s (slice (const 9'sd-256) 5:9))")
 240         self.assertRepr(Const(256, signed(9)).shift_left(-15),
 241                         "(s (slice (const 9'sd-256) 9:9))")
 242
 243     def test_shift_left_wrong(self):
 244         with self.assertRaisesRegex(TypeError,
 245                 r"^Shift amount must be an integer, not 'str'$"):
 246             Const(31).shift_left("str")
 247
 248     def test_shift_right(self):
 249         self.assertRepr(Const(256, unsigned(9)).shift_right(0),
 250                         "(slice (const 9'd256) 0:9)")
 251
 252         self.assertRepr(Const(256, unsigned(9)).shift_right(-1),
 253                         "(cat (const 1'd0) (const 9'd256))")
 254         self.assertRepr(Const(256, unsigned(9)).shift_right(-5),
 255                         "(cat (const 5'd0) (const 9'd256))")
 256         self.assertRepr(Const(256, signed(9)).shift_right(-1),
 257                         "(s (cat (const 1'd0) (const 9'sd-256)))")
 258         self.assertRepr(Const(256, signed(9)).shift_right(-5),
 259                         "(s (cat (const 5'd0) (const 9'sd-256)))")
 260
 261         self.assertRepr(Const(256, unsigned(9)).shift_right(1),
 262                         "(slice (const 9'd256) 1:9)")
 263         self.assertRepr(Const(256, unsigned(9)).shift_right(5),
 264                         "(slice (const 9'd256) 5:9)")
 265         self.assertRepr(Const(256, signed(9)).shift_right(1),
 266                         "(s (slice (const 9'sd-256) 1:9))")
 267         self.assertRepr(Const(256, signed(9)).shift_right(5),
 268                         "(s (slice (const 9'sd-256) 5:9))")
 269         self.assertRepr(Const(256, signed(9)).shift_right(15),
 270                         "(s (slice (const 9'sd-256) 9:9))")
 271
 272     def test_shift_right_wrong(self):
 273         with self.assertRaisesRegex(TypeError,
 274                 r"^Shift amount must be an integer, not 'str'$"):
 275             Const(31).shift_left("str")
 276
 277     def test_rotate_left(self):
 278         self.assertRepr(Const(256).rotate_left(1),
 279                         "(cat (slice (const 9'd256) 8:9) (slice (const 9'd256) 0:8))")
 280         self.assertRepr(Const(256).rotate_left(7),
 281                         "(cat (slice (const 9'd256) 2:9) (slice (const 9'd256) 0:2))")
 282         self.assertRepr(Const(256).rotate_left(-1),
 283                         "(cat (slice (const 9'd256) 1:9) (slice (const 9'd256) 0:1))")
 284         self.assertRepr(Const(256).rotate_left(-7),
 285                         "(cat (slice (const 9'd256) 7:9) (slice (const 9'd256) 0:7))")
 286
 287     def test_rotate_left_wrong(self):
 288         with self.assertRaisesRegex(TypeError,
 289                 r"^Rotate amount must be an integer, not 'str'$"):
 290             Const(31).rotate_left("str")
 291
 292     def test_rotate_right(self):
 293         self.assertRepr(Const(256).rotate_right(1),
 294                         "(cat (slice (const 9'd256) 1:9) (slice (const 9'd256) 0:1))")
 295         self.assertRepr(Const(256).rotate_right(7),
 296                         "(cat (slice (const 9'd256) 7:9) (slice (const 9'd256) 0:7))")
 297         self.assertRepr(Const(256).rotate_right(-1),
 298                         "(cat (slice (const 9'd256) 8:9) (slice (const 9'd256) 0:8))")
 299         self.assertRepr(Const(256).rotate_right(-7),
 300                         "(cat (slice (const 9'd256) 2:9) (slice (const 9'd256) 0:2))")
 301
 302     def test_rotate_right_wrong(self):
 303         with self.assertRaisesRegex(TypeError,
 304                 r"^Rotate amount must be an integer, not 'str'$"):
 305             Const(31).rotate_right("str")
 306
 307
 308 class ConstTestCase(FHDLTestCase):
 309     def test_shape(self):
 310         self.assertEqual(Const(0).shape(),   unsigned(1))
 311         self.assertIsInstance(Const(0).shape(), Shape)
 312         self.assertEqual(Const(1).shape(),   unsigned(1))
 313         self.assertEqual(Const(10).shape(),  unsigned(4))
 314         self.assertEqual(Const(-10).shape(), signed(5))
 315
 316         self.assertEqual(Const(1, 4).shape(),          unsigned(4))
 317         self.assertEqual(Const(-1, 4).shape(),         signed(4))
 318         self.assertEqual(Const(1, signed(4)).shape(),  signed(4))
 319         self.assertEqual(Const(0, unsigned(0)).shape(), unsigned(0))
 320
 321     def test_shape_wrong(self):
 322         with self.assertRaisesRegex(TypeError,
 323                 r"^Width must be a non-negative integer, not -1$"):
 324             Const(1, -1)
 325
 326     def test_normalization(self):
 327         self.assertEqual(Const(0b10110, signed(5)).value, -10)
 328
 329     def test_value(self):
 330         self.assertEqual(Const(10).value, 10)
 331
 332     def test_repr(self):
 333         self.assertEqual(repr(Const(10)),  "(const 4'd10)")
 334         self.assertEqual(repr(Const(-10)), "(const 5'sd-10)")
 335
 336     def test_hash(self):
 337         with self.assertRaises(TypeError):
 338             hash(Const(0))
 339
 340
 341 class OperatorTestCase(FHDLTestCase):
 342     def test_bool(self):
 343         v = Const(0, 4).bool()
 344         self.assertEqual(repr(v), "(b (const 4'd0))")
 345         self.assertEqual(v.shape(), unsigned(1))
 346
 347     def test_invert(self):
 348         v = ~Const(0, 4)
 349         self.assertEqual(repr(v), "(~ (const 4'd0))")
 350         self.assertEqual(v.shape(), unsigned(4))
 351
 352     def test_as_unsigned(self):
 353         v = Const(-1, signed(4)).as_unsigned()
 354         self.assertEqual(repr(v), "(u (const 4'sd-1))")
 355         self.assertEqual(v.shape(), unsigned(4))
 356
 357     def test_as_signed(self):
 358         v = Const(1, unsigned(4)).as_signed()
 359         self.assertEqual(repr(v), "(s (const 4'd1))")
 360         self.assertEqual(v.shape(), signed(4))
 361
 362     def test_neg(self):
 363         v1 = -Const(0, unsigned(4))
 364         self.assertEqual(repr(v1), "(- (const 4'd0))")
 365         self.assertEqual(v1.shape(), signed(5))
 366         v2 = -Const(0, signed(4))
 367         self.assertEqual(repr(v2), "(- (const 4'sd0))")
 368         self.assertEqual(v2.shape(), signed(5))
 369
 370     def test_add(self):
 371         v1 = Const(0, unsigned(4)) + Const(0, unsigned(6))
 372         self.assertEqual(repr(v1), "(+ (const 4'd0) (const 6'd0))")
 373         self.assertEqual(v1.shape(), unsigned(7))
 374         v2 = Const(0, signed(4)) + Const(0, signed(6))
 375         self.assertEqual(v2.shape(), signed(7))
 376         v3 = Const(0, signed(4)) + Const(0, unsigned(4))
 377         self.assertEqual(v3.shape(), signed(6))
 378         v4 = Const(0, unsigned(4)) + Const(0, signed(4))
 379         self.assertEqual(v4.shape(), signed(6))
 380         v5 = 10 + Const(0, 4)
 381         self.assertEqual(v5.shape(), unsigned(5))
 382
 383     def test_sub(self):
 384         v1 = Const(0, unsigned(4)) - Const(0, unsigned(6))
 385         self.assertEqual(repr(v1), "(- (const 4'd0) (const 6'd0))")
 386         self.assertEqual(v1.shape(), unsigned(7))
 387         v2 = Const(0, signed(4)) - Const(0, signed(6))
 388         self.assertEqual(v2.shape(), signed(7))
 389         v3 = Const(0, signed(4)) - Const(0, unsigned(4))
 390         self.assertEqual(v3.shape(), signed(6))
 391         v4 = Const(0, unsigned(4)) - Const(0, signed(4))
 392         self.assertEqual(v4.shape(), signed(6))
 393         v5 = 10 - Const(0, 4)
 394         self.assertEqual(v5.shape(), unsigned(5))
 395
 396     def test_mul(self):
 397         v1 = Const(0, unsigned(4)) * Const(0, unsigned(6))
 398         self.assertEqual(repr(v1), "(* (const 4'd0) (const 6'd0))")
 399         self.assertEqual(v1.shape(), unsigned(10))
 400         v2 = Const(0, signed(4)) * Const(0, signed(6))
 401         self.assertEqual(v2.shape(), signed(10))
 402         v3 = Const(0, signed(4)) * Const(0, unsigned(4))
 403         self.assertEqual(v3.shape(), signed(8))
 404         v5 = 10 * Const(0, 4)
 405         self.assertEqual(v5.shape(), unsigned(8))
 406
 407     def test_mod(self):
 408         v1 = Const(0, unsigned(4)) % Const(0, unsigned(6))
 409         self.assertEqual(repr(v1), "(% (const 4'd0) (const 6'd0))")
 410         self.assertEqual(v1.shape(), unsigned(4))
 411         v3 = Const(0, signed(4)) % Const(0, unsigned(4))
 412         self.assertEqual(v3.shape(), signed(4))
 413         v5 = 10 % Const(0, 4)
 414         self.assertEqual(v5.shape(), unsigned(4))
 415
 416     def test_mod_wrong(self):
 417         with self.assertRaisesRegex(NotImplementedError,
 418                 r"^Division by a signed value is not supported$"):
 419             Const(0, signed(4)) % Const(0, signed(6))
 420
 421     def test_floordiv(self):
 422         v1 = Const(0, unsigned(4)) // Const(0, unsigned(6))
 423         self.assertEqual(repr(v1), "(// (const 4'd0) (const 6'd0))")
 424         self.assertEqual(v1.shape(), unsigned(4))
 425         v3 = Const(0, signed(4)) // Const(0, unsigned(4))
 426         self.assertEqual(v3.shape(), signed(4))
 427         v5 = 10 // Const(0, 4)
 428         self.assertEqual(v5.shape(), unsigned(4))
 429
 430     def test_floordiv_wrong(self):
 431         with self.assertRaisesRegex(NotImplementedError,
 432                 r"^Division by a signed value is not supported$"):
 433             Const(0, signed(4)) // Const(0, signed(6))
 434
 435     def test_and(self):
 436         v1 = Const(0, unsigned(4)) & Const(0, unsigned(6))
 437         self.assertEqual(repr(v1), "(& (const 4'd0) (const 6'd0))")
 438         self.assertEqual(v1.shape(), unsigned(6))
 439         v2 = Const(0, signed(4)) & Const(0, signed(6))
 440         self.assertEqual(v2.shape(), signed(6))
 441         v3 = Const(0, signed(4)) & Const(0, unsigned(4))
 442         self.assertEqual(v3.shape(), signed(5))
 443         v4 = Const(0, unsigned(4)) & Const(0, signed(4))
 444         self.assertEqual(v4.shape(), signed(5))
 445         v5 = 10 & Const(0, 4)
 446         self.assertEqual(v5.shape(), unsigned(4))
 447
 448     def test_or(self):
 449         v1 = Const(0, unsigned(4)) | Const(0, unsigned(6))
 450         self.assertEqual(repr(v1), "(| (const 4'd0) (const 6'd0))")
 451         self.assertEqual(v1.shape(), unsigned(6))
 452         v2 = Const(0, signed(4)) | Const(0, signed(6))
 453         self.assertEqual(v2.shape(), signed(6))
 454         v3 = Const(0, signed(4)) | Const(0, unsigned(4))
 455         self.assertEqual(v3.shape(), signed(5))
 456         v4 = Const(0, unsigned(4)) | Const(0, signed(4))
 457         self.assertEqual(v4.shape(), signed(5))
 458         v5 = 10 | Const(0, 4)
 459         self.assertEqual(v5.shape(), unsigned(4))
 460
 461     def test_xor(self):
 462         v1 = Const(0, unsigned(4)) ^ Const(0, unsigned(6))
 463         self.assertEqual(repr(v1), "(^ (const 4'd0) (const 6'd0))")
 464         self.assertEqual(v1.shape(), unsigned(6))
 465         v2 = Const(0, signed(4)) ^ Const(0, signed(6))
 466         self.assertEqual(v2.shape(), signed(6))
 467         v3 = Const(0, signed(4)) ^ Const(0, unsigned(4))
 468         self.assertEqual(v3.shape(), signed(5))
 469         v4 = Const(0, unsigned(4)) ^ Const(0, signed(4))
 470         self.assertEqual(v4.shape(), signed(5))
 471         v5 = 10 ^ Const(0, 4)
 472         self.assertEqual(v5.shape(), unsigned(4))
 473
 474     def test_shl(self):
 475         v1 = Const(1, 4) << Const(4)
 476         self.assertEqual(repr(v1), "(<< (const 4'd1) (const 3'd4))")
 477         self.assertEqual(v1.shape(), unsigned(11))
 478
 479     def test_shl_wrong(self):
 480         with self.assertRaisesRegex(TypeError,
 481                 r"^Shift amount must be unsigned$"):
 482             1 << Const(0, signed(6))
 483         with self.assertRaisesRegex(TypeError,
 484                 r"^Shift amount must be unsigned$"):
 485             Const(1, unsigned(4)) << -1
 486
 487     def test_shr(self):
 488         v1 = Const(1, 4) >> Const(4)
 489         self.assertEqual(repr(v1), "(>> (const 4'd1) (const 3'd4))")
 490         self.assertEqual(v1.shape(), unsigned(4))
 491
 492     def test_shr_wrong(self):
 493         with self.assertRaisesRegex(TypeError,
 494                 r"^Shift amount must be unsigned$"):
 495             1 << Const(0, signed(6))
 496         with self.assertRaisesRegex(TypeError,
 497                 r"^Shift amount must be unsigned$"):
 498             Const(1, unsigned(4)) << -1
 499
 500     def test_lt(self):
 501         v = Const(0, 4) < Const(0, 6)
 502         self.assertEqual(repr(v), "(< (const 4'd0) (const 6'd0))")
 503         self.assertEqual(v.shape(), unsigned(1))
 504
 505     def test_le(self):
 506         v = Const(0, 4) <= Const(0, 6)
 507         self.assertEqual(repr(v), "(<= (const 4'd0) (const 6'd0))")
 508         self.assertEqual(v.shape(), unsigned(1))
 509
 510     def test_gt(self):
 511         v = Const(0, 4) > Const(0, 6)
 512         self.assertEqual(repr(v), "(> (const 4'd0) (const 6'd0))")
 513         self.assertEqual(v.shape(), unsigned(1))
 514
 515     def test_ge(self):
 516         v = Const(0, 4) >= Const(0, 6)
 517         self.assertEqual(repr(v), "(>= (const 4'd0) (const 6'd0))")
 518         self.assertEqual(v.shape(), unsigned(1))
 519
 520     def test_eq(self):
 521         v = Const(0, 4) == Const(0, 6)
 522         self.assertEqual(repr(v), "(== (const 4'd0) (const 6'd0))")
 523         self.assertEqual(v.shape(), unsigned(1))
 524
 525     def test_ne(self):
 526         v = Const(0, 4) != Const(0, 6)
 527         self.assertEqual(repr(v), "(!= (const 4'd0) (const 6'd0))")
 528         self.assertEqual(v.shape(), unsigned(1))
 529
 530     def test_mux(self):
 531         s  = Const(0)
 532         v1 = Mux(s, Const(0, unsigned(4)), Const(0, unsigned(6)))
 533         self.assertEqual(repr(v1), "(m (const 1'd0) (const 4'd0) (const 6'd0))")
 534         self.assertEqual(v1.shape(), unsigned(6))
 535         v2 = Mux(s, Const(0, signed(4)), Const(0, signed(6)))
 536         self.assertEqual(v2.shape(), signed(6))
 537         v3 = Mux(s, Const(0, signed(4)), Const(0, unsigned(4)))
 538         self.assertEqual(v3.shape(), signed(5))
 539         v4 = Mux(s, Const(0, unsigned(4)), Const(0, signed(4)))
 540         self.assertEqual(v4.shape(), signed(5))
 541
 542     def test_mux_wide(self):
 543         s = Const(0b100)
 544         v = Mux(s, Const(0, unsigned(4)), Const(0, unsigned(6)))
 545         self.assertEqual(repr(v), "(m (b (const 3'd4)) (const 4'd0) (const 6'd0))")
 546
 547     def test_mux_bool(self):
 548         v = Mux(True, Const(0), Const(0))
 549         self.assertEqual(repr(v), "(m (const 1'd1) (const 1'd0) (const 1'd0))")
 550
 551     def test_any(self):
 552         v = Const(0b101).any()
 553         self.assertEqual(repr(v), "(r| (const 3'd5))")
 554
 555     def test_all(self):
 556         v = Const(0b101).all()
 557         self.assertEqual(repr(v), "(r& (const 3'd5))")
 558
 559     def test_xor_value(self):
 560         v = Const(0b101).xor()
 561         self.assertEqual(repr(v), "(r^ (const 3'd5))")
 562
 563     def test_matches(self):
 564         s = Signal(4)
 565         self.assertRepr(s.matches(), "(const 1'd0)")
 566         self.assertRepr(s.matches(1), """
 567         (== (sig s) (const 1'd1))
 568         """)
 569         self.assertRepr(s.matches(0, 1), """
 570         (r| (cat (== (sig s) (const 1'd0)) (== (sig s) (const 1'd1))))
 571         """)
 572         self.assertRepr(s.matches("10--"), """
 573         (== (& (sig s) (const 4'd12)) (const 4'd8))
 574         """)
 575         self.assertRepr(s.matches("1 0--"), """
 576         (== (& (sig s) (const 4'd12)) (const 4'd8))
 577         """)
 578
 579     def test_matches_enum(self):
 580         s = Signal(SignedEnum)
 581         self.assertRepr(s.matches(SignedEnum.FOO), """
 582         (== (sig s) (const 1'sd-1))
 583         """)
 584
 585     def test_matches_width_wrong(self):
 586         s = Signal(4)
 587         with self.assertRaisesRegex(SyntaxError,
 588                 r"^Match pattern '--' must have the same width as match value \(which is 4\)$"):
 589             s.matches("--")
 590         with self.assertWarnsRegex(SyntaxWarning,
 591                 (r"^Match pattern '10110' is wider than match value \(which has width 4\); "
 592                     r"comparison will never be true$")):
 593             s.matches(0b10110)
 594
 595     def test_matches_bits_wrong(self):
 596         s = Signal(4)
 597         with self.assertRaisesRegex(SyntaxError,
 598                 (r"^Match pattern 'abc' must consist of 0, 1, and - \(don't care\) bits, "
 599                     r"and may include whitespace$")):
 600             s.matches("abc")
 601
 602     def test_matches_pattern_wrong(self):
 603         s = Signal(4)
 604         with self.assertRaisesRegex(SyntaxError,
 605                 r"^Match pattern must be an integer, a string, or an enumeration, not 1\.0$"):
 606             s.matches(1.0)
 607
 608     def test_hash(self):
 609         with self.assertRaises(TypeError):
 610             hash(Const(0) + Const(0))
 611
 612
 613 class SliceTestCase(FHDLTestCase):
 614     def test_shape(self):
 615         s1 = Const(10)[2]
 616         self.assertEqual(s1.shape(), unsigned(1))
 617         self.assertIsInstance(s1.shape(), Shape)
 618         s2 = Const(-10)[0:2]
 619         self.assertEqual(s2.shape(), unsigned(2))
 620
 621     def test_start_end_negative(self):
 622         c  = Const(0, 8)
 623         s1 = Slice(c, 0, -1)
 624         self.assertEqual((s1.start, s1.stop), (0, 7))
 625         s1 = Slice(c, -4, -1)
 626         self.assertEqual((s1.start, s1.stop), (4, 7))
 627
 628     def test_start_end_bool(self):
 629         c  = Const(0, 8)
 630         s  = Slice(c, False, True)
 631         self.assertIs(type(s.start), int)
 632         self.assertIs(type(s.stop),  int)
 633
 634     def test_start_end_wrong(self):
 635         with self.assertRaisesRegex(TypeError,
 636                 r"^Slice start must be an integer, not 'x'$"):
 637             Slice(0, "x", 1)
 638         with self.assertRaisesRegex(TypeError,
 639                 r"^Slice stop must be an integer, not 'x'$"):
 640             Slice(0, 1, "x")
 641
 642     def test_start_end_out_of_range(self):
 643         c = Const(0, 8)
 644         with self.assertRaisesRegex(IndexError,
 645                 r"^Cannot start slice 10 bits into 8-bit value$"):
 646             Slice(c, 10, 12)
 647         with self.assertRaisesRegex(IndexError,
 648                 r"^Cannot stop slice 12 bits into 8-bit value$"):
 649             Slice(c, 0, 12)
 650         with self.assertRaisesRegex(IndexError,
 651                 r"^Slice start 4 must be less than slice stop 2$"):
 652             Slice(c, 4, 2)
 653
 654     def test_repr(self):
 655         s1 = Const(10)[2]
 656         self.assertEqual(repr(s1), "(slice (const 4'd10) 2:3)")
 657
 658
 659 class BitSelectTestCase(FHDLTestCase):
 660     def setUp(self):
 661         self.c = Const(0, 8)
 662         self.s = Signal(range(self.c.width))
 663
 664     def test_shape(self):
 665         s1 = self.c.bit_select(self.s, 2)
 666         self.assertIsInstance(s1, Part)
 667         self.assertEqual(s1.shape(), unsigned(2))
 668         self.assertIsInstance(s1.shape(), Shape)
 669         s2 = self.c.bit_select(self.s, 0)
 670         self.assertIsInstance(s2, Part)
 671         self.assertEqual(s2.shape(), unsigned(0))
 672
 673     def test_stride(self):
 674         s1 = self.c.bit_select(self.s, 2)
 675         self.assertIsInstance(s1, Part)
 676         self.assertEqual(s1.stride, 1)
 677
 678     def test_const(self):
 679         s1 = self.c.bit_select(1, 2)
 680         self.assertIsInstance(s1, Slice)
 681         self.assertRepr(s1, """(slice (const 8'd0) 1:3)""")
 682
 683     def test_width_wrong(self):
 684         with self.assertRaises(TypeError):
 685             self.c.bit_select(self.s, -1)
 686
 687     def test_repr(self):
 688         s = self.c.bit_select(self.s, 2)
 689         self.assertEqual(repr(s), "(part (const 8'd0) (sig s) 2 1)")
 690
 691
 692 class WordSelectTestCase(FHDLTestCase):
 693     def setUp(self):
 694         self.c = Const(0, 8)
 695         self.s = Signal(range(self.c.width))
 696
 697     def test_shape(self):
 698         s1 = self.c.word_select(self.s, 2)
 699         self.assertIsInstance(s1, Part)
 700         self.assertEqual(s1.shape(), unsigned(2))
 701         self.assertIsInstance(s1.shape(), Shape)
 702
 703     def test_stride(self):
 704         s1 = self.c.word_select(self.s, 2)
 705         self.assertIsInstance(s1, Part)
 706         self.assertEqual(s1.stride, 2)
 707
 708     def test_const(self):
 709         s1 = self.c.word_select(1, 2)
 710         self.assertIsInstance(s1, Slice)
 711         self.assertRepr(s1, """(slice (const 8'd0) 2:4)""")
 712
 713     def test_width_wrong(self):
 714         with self.assertRaises(TypeError):
 715             self.c.word_select(self.s, 0)
 716         with self.assertRaises(TypeError):
 717             self.c.word_select(self.s, -1)
 718
 719     def test_repr(self):
 720         s = self.c.word_select(self.s, 2)
 721         self.assertEqual(repr(s), "(part (const 8'd0) (sig s) 2 2)")
 722
 723
 724 class CatTestCase(FHDLTestCase):
 725     def test_shape(self):
 726         c0 = Cat()
 727         self.assertEqual(c0.shape(), unsigned(0))
 728         self.assertIsInstance(c0.shape(), Shape)
 729         c1 = Cat(Const(10))
 730         self.assertEqual(c1.shape(), unsigned(4))
 731         c2 = Cat(Const(10), Const(1))
 732         self.assertEqual(c2.shape(), unsigned(5))
 733         c3 = Cat(Const(10), Const(1), Const(0))
 734         self.assertEqual(c3.shape(), unsigned(6))
 735
 736     def test_repr(self):
 737         c1 = Cat(Const(10), Const(1))
 738         self.assertEqual(repr(c1), "(cat (const 4'd10) (const 1'd1))")
 739
 740
 741 class ReplTestCase(FHDLTestCase):
 742     def test_shape(self):
 743         s1 = Repl(Const(10), 3)
 744         self.assertEqual(s1.shape(), unsigned(12))
 745         self.assertIsInstance(s1.shape(), Shape)
 746         s2 = Repl(Const(10), 0)
 747         self.assertEqual(s2.shape(), unsigned(0))
 748
 749     def test_count_wrong(self):
 750         with self.assertRaises(TypeError):
 751             Repl(Const(10), -1)
 752         with self.assertRaises(TypeError):
 753             Repl(Const(10), "str")
 754
 755     def test_repr(self):
 756         s = Repl(Const(10), 3)
 757         self.assertEqual(repr(s), "(repl (const 4'd10) 3)")
 758
 759
 760 class ArrayTestCase(FHDLTestCase):
 761     def test_acts_like_array(self):
 762         a = Array([1,2,3])
 763         self.assertSequenceEqual(a, [1,2,3])
 764         self.assertEqual(a[1], 2)
 765         a[1] = 4
 766         self.assertSequenceEqual(a, [1,4,3])
 767         del a[1]
 768         self.assertSequenceEqual(a, [1,3])
 769         a.insert(1, 2)
 770         self.assertSequenceEqual(a, [1,2,3])
 771
 772     def test_becomes_immutable(self):
 773         a = Array([1,2,3])
 774         s1 = Signal(range(len(a)))
 775         s2 = Signal(range(len(a)))
 776         v1 = a[s1]
 777         v2 = a[s2]
 778         with self.assertRaisesRegex(ValueError,
 779                 r"^Array can no longer be mutated after it was indexed with a value at "):
 780             a[1] = 2
 781         with self.assertRaisesRegex(ValueError,
 782                 r"^Array can no longer be mutated after it was indexed with a value at "):
 783             del a[1]
 784         with self.assertRaisesRegex(ValueError,
 785                 r"^Array can no longer be mutated after it was indexed with a value at "):
 786             a.insert(1, 2)
 787
 788     def test_repr(self):
 789         a = Array([1,2,3])
 790         self.assertEqual(repr(a), "(array mutable [1, 2, 3])")
 791         s = Signal(range(len(a)))
 792         v = a[s]
 793         self.assertEqual(repr(a), "(array [1, 2, 3])")
 794
 795
 796 class ArrayProxyTestCase(FHDLTestCase):
 797     def test_index_shape(self):
 798         m = Array(Array(x * y for y in range(1, 4)) for x in range(1, 4))
 799         a = Signal(range(3))
 800         b = Signal(range(3))
 801         v = m[a][b]
 802         self.assertEqual(v.shape(), unsigned(4))
 803
 804     def test_attr_shape(self):
 805         from collections import namedtuple
 806         pair = namedtuple("pair", ("p", "n"))
 807         a = Array(pair(i, -i) for i in range(10))
 808         s = Signal(range(len(a)))
 809         v = a[s]
 810         self.assertEqual(v.p.shape(), unsigned(4))
 811         self.assertEqual(v.n.shape(), signed(5))
 812
 813     def test_attr_shape_signed(self):
 814         # [unsigned(1), unsigned(1)] → unsigned(1)
 815         a1 = Array([1, 1])
 816         v1 = a1[Const(0)]
 817         self.assertEqual(v1.shape(), unsigned(1))
 818         # [signed(1), signed(1)] → signed(1)
 819         a2 = Array([-1, -1])
 820         v2 = a2[Const(0)]
 821         self.assertEqual(v2.shape(), signed(1))
 822         # [unsigned(1), signed(2)] → signed(2)
 823         a3 = Array([1, -2])
 824         v3 = a3[Const(0)]
 825         self.assertEqual(v3.shape(), signed(2))
 826         # [unsigned(1), signed(1)] → signed(2); 1st operand padded with sign bit!
 827         a4 = Array([1, -1])
 828         v4 = a4[Const(0)]
 829         self.assertEqual(v4.shape(), signed(2))
 830         # [unsigned(2), signed(1)] → signed(3); 1st operand padded with sign bit!
 831         a5 = Array([1, -1])
 832         v5 = a5[Const(0)]
 833         self.assertEqual(v5.shape(), signed(2))
 834
 835     def test_repr(self):
 836         a = Array([1, 2, 3])
 837         s = Signal(range(3))
 838         v = a[s]
 839         self.assertEqual(repr(v), "(proxy (array [1, 2, 3]) (sig s))")
 840
 841
 842 class SignalTestCase(FHDLTestCase):
 843     def test_shape(self):
 844         s1 = Signal()
 845         self.assertEqual(s1.shape(), unsigned(1))
 846         self.assertIsInstance(s1.shape(), Shape)
 847         s2 = Signal(2)
 848         self.assertEqual(s2.shape(), unsigned(2))
 849         s3 = Signal(unsigned(2))
 850         self.assertEqual(s3.shape(), unsigned(2))
 851         s4 = Signal(signed(2))
 852         self.assertEqual(s4.shape(), signed(2))
 853         s5 = Signal(0)
 854         self.assertEqual(s5.shape(), unsigned(0))
 855         s6 = Signal(range(16))
 856         self.assertEqual(s6.shape(), unsigned(4))
 857         s7 = Signal(range(4, 16))
 858         self.assertEqual(s7.shape(), unsigned(4))
 859         s8 = Signal(range(-4, 16))
 860         self.assertEqual(s8.shape(), signed(5))
 861         s9 = Signal(range(-20, 16))
 862         self.assertEqual(s9.shape(), signed(6))
 863         s10 = Signal(range(0))
 864         self.assertEqual(s10.shape(), unsigned(0))
 865         s11 = Signal(range(1))
 866         self.assertEqual(s11.shape(), unsigned(1))
 867
 868     def test_shape_wrong(self):
 869         with self.assertRaisesRegex(TypeError,
 870                 r"^Width must be a non-negative integer, not -10$"):
 871             Signal(-10)
 872
 873     def test_name(self):
 874         s1 = Signal()
 875         self.assertEqual(s1.name, "s1")
 876         s2 = Signal(name="sig")
 877         self.assertEqual(s2.name, "sig")
 878
 879     def test_reset(self):
 880         s1 = Signal(4, reset=0b111, reset_less=True)
 881         self.assertEqual(s1.reset, 0b111)
 882         self.assertEqual(s1.reset_less, True)
 883
 884     def test_reset_enum(self):
 885         s1 = Signal(2, reset=UnsignedEnum.BAR)
 886         self.assertEqual(s1.reset, 2)
 887         with self.assertRaisesRegex(TypeError,
 888                 r"^Reset value has to be an int or an integral Enum$"
 889         ):
 890             Signal(1, reset=StringEnum.FOO)
 891
 892     def test_reset_narrow(self):
 893         with self.assertWarnsRegex(SyntaxWarning,
 894                 r"^Reset value 8 requires 4 bits to represent, but the signal only has 3 bits$"):
 895             Signal(3, reset=8)
 896         with self.assertWarnsRegex(SyntaxWarning,
 897                 r"^Reset value 4 requires 4 bits to represent, but the signal only has 3 bits$"):
 898             Signal(signed(3), reset=4)
 899         with self.assertWarnsRegex(SyntaxWarning,
 900                 r"^Reset value -5 requires 4 bits to represent, but the signal only has 3 bits$"):
 901             Signal(signed(3), reset=-5)
 902
 903     def test_attrs(self):
 904         s1 = Signal()
 905         self.assertEqual(s1.attrs, {})
 906         s2 = Signal(attrs={"no_retiming": True})
 907         self.assertEqual(s2.attrs, {"no_retiming": True})
 908
 909     def test_repr(self):
 910         s1 = Signal()
 911         self.assertEqual(repr(s1), "(sig s1)")
 912
 913     def test_like(self):
 914         s1 = Signal.like(Signal(4))
 915         self.assertEqual(s1.shape(), unsigned(4))
 916         s2 = Signal.like(Signal(range(-15, 1)))
 917         self.assertEqual(s2.shape(), signed(5))
 918         s3 = Signal.like(Signal(4, reset=0b111, reset_less=True))
 919         self.assertEqual(s3.reset, 0b111)
 920         self.assertEqual(s3.reset_less, True)
 921         s4 = Signal.like(Signal(attrs={"no_retiming": True}))
 922         self.assertEqual(s4.attrs, {"no_retiming": True})
 923         s5 = Signal.like(Signal(decoder=str))
 924         self.assertEqual(s5.decoder, str)
 925         s6 = Signal.like(10)
 926         self.assertEqual(s6.shape(), unsigned(4))
 927         s7 = [Signal.like(Signal(4))][0]
 928         self.assertEqual(s7.name, "$like")
 929         s8 = Signal.like(s1, name_suffix="_ff")
 930         self.assertEqual(s8.name, "s1_ff")
 931
 932     def test_decoder(self):
 933         class Color(Enum):
 934             RED  = 1
 935             BLUE = 2
 936         s = Signal(decoder=Color)
 937         self.assertEqual(s.decoder(1), "RED/1")
 938         self.assertEqual(s.decoder(3), "3")
 939
 940     def test_enum(self):
 941         s1 = Signal(UnsignedEnum)
 942         self.assertEqual(s1.shape(), unsigned(2))
 943         s2 = Signal(SignedEnum)
 944         self.assertEqual(s2.shape(), signed(2))
 945         self.assertEqual(s2.decoder(SignedEnum.FOO), "FOO/-1")
 946
 947
 948 class ClockSignalTestCase(FHDLTestCase):
 949     def test_domain(self):
 950         s1 = ClockSignal()
 951         self.assertEqual(s1.domain, "sync")
 952         s2 = ClockSignal("pix")
 953         self.assertEqual(s2.domain, "pix")
 954
 955         with self.assertRaisesRegex(TypeError,
 956                 r"^Clock domain name must be a string, not 1$"):
 957             ClockSignal(1)
 958
 959     def test_shape(self):
 960         s1 = ClockSignal()
 961         self.assertEqual(s1.shape(), unsigned(1))
 962         self.assertIsInstance(s1.shape(), Shape)
 963
 964     def test_repr(self):
 965         s1 = ClockSignal()
 966         self.assertEqual(repr(s1), "(clk sync)")
 967
 968     def test_wrong_name_comb(self):
 969         with self.assertRaisesRegex(ValueError,
 970                 r"^Domain 'comb' does not have a clock$"):
 971             ClockSignal("comb")
 972
 973
 974 class ResetSignalTestCase(FHDLTestCase):
 975     def test_domain(self):
 976         s1 = ResetSignal()
 977         self.assertEqual(s1.domain, "sync")
 978         s2 = ResetSignal("pix")
 979         self.assertEqual(s2.domain, "pix")
 980
 981         with self.assertRaisesRegex(TypeError,
 982                 r"^Clock domain name must be a string, not 1$"):
 983             ResetSignal(1)
 984
 985     def test_shape(self):
 986         s1 = ResetSignal()
 987         self.assertEqual(s1.shape(), unsigned(1))
 988         self.assertIsInstance(s1.shape(), Shape)
 989
 990     def test_repr(self):
 991         s1 = ResetSignal()
 992         self.assertEqual(repr(s1), "(rst sync)")
 993
 994     def test_wrong_name_comb(self):
 995         with self.assertRaisesRegex(ValueError,
 996                 r"^Domain 'comb' does not have a reset$"):
 997             ResetSignal("comb")
 998
 999
1000 class MockUserValue(UserValue):
1001     def __init__(self, lowered):
1002         super().__init__()
1003         self.lower_count = 0
1004         self.lowered     = lowered
1005
1006     def lower(self):
1007         self.lower_count += 1
1008         return self.lowered
1009
1010
1011 class UserValueTestCase(FHDLTestCase):
1012     def test_shape(self):
1013         with warnings.catch_warnings():
1014             warnings.filterwarnings(action="ignore", category=DeprecationWarning)
1015             uv = MockUserValue(1)
1016             self.assertEqual(uv.shape(), unsigned(1))
1017             self.assertIsInstance(uv.shape(), Shape)
1018             uv.lowered = 2
1019             self.assertEqual(uv.shape(), unsigned(1))
1020             self.assertEqual(uv.lower_count, 1)
1021
1022     def test_lower_to_user_value(self):
1023         with warnings.catch_warnings():
1024             warnings.filterwarnings(action="ignore", category=DeprecationWarning)
1025             uv = MockUserValue(MockUserValue(1))
1026             self.assertEqual(uv.shape(), unsigned(1))
1027             self.assertIsInstance(uv.shape(), Shape)
1028             uv.lowered = MockUserValue(2)
1029             self.assertEqual(uv.shape(), unsigned(1))
1030             self.assertEqual(uv.lower_count, 1)
1031
1032
1033 class MockValueCastableChanges(ValueCastable):
1034     def __init__(self, width=0):
1035         self.width = width
1036
1037     @ValueCastable.lowermethod
1038     def as_value(self):
1039         return Signal(self.width)
1040
1041
1042 class MockValueCastableNotDecorated(ValueCastable):
1043     def __init__(self):
1044         pass
1045
1046     def as_value(self):
1047         return Signal()
1048
1049
1050 class MockValueCastableNoOverride(ValueCastable):
1051     def __init__(self):
1052         pass
1053
1054
1055 class ValueCastableTestCase(FHDLTestCase):
1056     def test_not_decorated(self):
1057         with self.assertRaisesRegex(TypeError,
1058                 r"^Class 'MockValueCastableNotDecorated' deriving from `ValueCastable` must decorate the `as_value` "
1059                 r"method with the `ValueCastable.lowermethod` decorator$"):
1060             vc = MockValueCastableNotDecorated()
1061
1062     def test_no_override(self):
1063         with self.assertRaisesRegex(TypeError,
1064                 r"^Class 'MockValueCastableNoOverride' deriving from `ValueCastable` must override the `as_value` "
1065                 r"method$"):
1066             vc = MockValueCastableNoOverride()
1067
1068     def test_memoized(self):
1069         vc = MockValueCastableChanges(1)
1070         sig1 = vc.as_value()
1071         vc.width = 2
1072         sig2 = vc.as_value()
1073         self.assertIs(sig1, sig2)
1074         vc.width = 3
1075         sig3 = Value.cast(vc)
1076         self.assertIs(sig1, sig3)
1077
1078
1079 class SampleTestCase(FHDLTestCase):
1080     def test_const(self):
1081         s = Sample(1, 1, "sync")
1082         self.assertEqual(s.shape(), unsigned(1))
1083
1084     def test_signal(self):
1085         s1 = Sample(Signal(2), 1, "sync")
1086         self.assertEqual(s1.shape(), unsigned(2))
1087         s2 = Sample(ClockSignal(), 1, "sync")
1088         s3 = Sample(ResetSignal(), 1, "sync")
1089
1090     def test_wrong_value_operator(self):
1091         with self.assertRaisesRegex(TypeError,
1092                 (r"^Sampled value must be a signal or a constant, not "
1093                 r"\(\+ \(sig \$signal\) \(const 1'd1\)\)$")):
1094             Sample(Signal() + 1, 1, "sync")
1095
1096     def test_wrong_clocks_neg(self):
1097         with self.assertRaisesRegex(ValueError,
1098                 r"^Cannot sample a value 1 cycles in the future$"):
1099             Sample(Signal(), -1, "sync")
1100
1101     def test_wrong_domain(self):
1102         with self.assertRaisesRegex(TypeError,
1103                 r"^Domain name must be a string or None, not 0$"):
1104             Sample(Signal(), 1, 0)
1105
1106
1107 class InitialTestCase(FHDLTestCase):
1108     def test_initial(self):
1109         i = Initial()
1110         self.assertEqual(i.shape(), unsigned(1))
1111
1112
1113 class SwitchTestCase(FHDLTestCase):
1114     def test_default_case(self):
1115         s = Switch(Const(0), {None: []})
1116         self.assertEqual(s.cases, {(): []})
1117
1118     def test_int_case(self):
1119         s = Switch(Const(0, 8), {10: []})
1120         self.assertEqual(s.cases, {("00001010",): []})
1121
1122     def test_int_neg_case(self):
1123         s = Switch(Const(0, 8), {-10: []})
1124         self.assertEqual(s.cases, {("11110110",): []})
1125
1126     def test_enum_case(self):
1127         s = Switch(Const(0, UnsignedEnum), {UnsignedEnum.FOO: []})
1128         self.assertEqual(s.cases, {("01",): []})
1129
1130     def test_str_case(self):
1131         s = Switch(Const(0, 8), {"0000 11\t01": []})
1132         self.assertEqual(s.cases, {("00001101",): []})
1133
1134     def test_two_cases(self):
1135         s = Switch(Const(0, 8), {("00001111", 123): []})
1136         self.assertEqual(s.cases, {("00001111", "01111011"): []})