Eric V. Smith | 9a4135e | 2019-05-08 16:28:48 -0400 | [diff] [blame] | 1 | # -*- coding: utf-8 -*- |
| 2 | # There are tests here with unicode string literals and |
| 3 | # identifiers. There's a code in ast.c that was added because of a |
| 4 | # failure with a non-ascii-only expression. So, I have tests for |
| 5 | # that. There are workarounds that would let me run tests for that |
| 6 | # code without unicode identifiers and strings, but just using them |
| 7 | # directly seems like the easiest and therefore safest thing to do. |
| 8 | # Unicode identifiers in tests is allowed by PEP 3131. |
| 9 | |
Eric V. Smith | 235a6f0 | 2015-09-19 14:51:32 -0400 | [diff] [blame] | 10 | import ast |
| 11 | import types |
| 12 | import decimal |
| 13 | import unittest |
| 14 | |
| 15 | a_global = 'global variable' |
| 16 | |
| 17 | # You could argue that I'm too strict in looking for specific error |
| 18 | # values with assertRaisesRegex, but without it it's way too easy to |
| 19 | # make a syntax error in the test strings. Especially with all of the |
| 20 | # triple quotes, raw strings, backslashes, etc. I think it's a |
| 21 | # worthwhile tradeoff. When I switched to this method, I found many |
| 22 | # examples where I wasn't testing what I thought I was. |
| 23 | |
| 24 | class TestCase(unittest.TestCase): |
| 25 | def assertAllRaise(self, exception_type, regex, error_strings): |
| 26 | for str in error_strings: |
| 27 | with self.subTest(str=str): |
| 28 | with self.assertRaisesRegex(exception_type, regex): |
| 29 | eval(str) |
| 30 | |
| 31 | def test__format__lookup(self): |
| 32 | # Make sure __format__ is looked up on the type, not the instance. |
| 33 | class X: |
| 34 | def __format__(self, spec): |
| 35 | return 'class' |
| 36 | |
| 37 | x = X() |
| 38 | |
| 39 | # Add a bound __format__ method to the 'y' instance, but not |
| 40 | # the 'x' instance. |
| 41 | y = X() |
| 42 | y.__format__ = types.MethodType(lambda self, spec: 'instance', y) |
| 43 | |
| 44 | self.assertEqual(f'{y}', format(y)) |
| 45 | self.assertEqual(f'{y}', 'class') |
| 46 | self.assertEqual(format(x), format(y)) |
| 47 | |
| 48 | # __format__ is not called this way, but still make sure it |
| 49 | # returns what we expect (so we can make sure we're bypassing |
| 50 | # it). |
| 51 | self.assertEqual(x.__format__(''), 'class') |
| 52 | self.assertEqual(y.__format__(''), 'instance') |
| 53 | |
| 54 | # This is how __format__ is actually called. |
| 55 | self.assertEqual(type(x).__format__(x, ''), 'class') |
| 56 | self.assertEqual(type(y).__format__(y, ''), 'class') |
| 57 | |
| 58 | def test_ast(self): |
| 59 | # Inspired by http://bugs.python.org/issue24975 |
| 60 | class X: |
| 61 | def __init__(self): |
| 62 | self.called = False |
| 63 | def __call__(self): |
| 64 | self.called = True |
| 65 | return 4 |
| 66 | x = X() |
| 67 | expr = """ |
| 68 | a = 10 |
| 69 | f'{a * x()}'""" |
| 70 | t = ast.parse(expr) |
| 71 | c = compile(t, '', 'exec') |
| 72 | |
| 73 | # Make sure x was not called. |
| 74 | self.assertFalse(x.called) |
| 75 | |
| 76 | # Actually run the code. |
| 77 | exec(c) |
| 78 | |
| 79 | # Make sure x was called. |
| 80 | self.assertTrue(x.called) |
| 81 | |
Łukasz Langa | e7c566c | 2017-09-06 17:27:58 -0700 | [diff] [blame] | 82 | def test_ast_line_numbers(self): |
| 83 | expr = """ |
| 84 | a = 10 |
| 85 | f'{a * x()}'""" |
| 86 | t = ast.parse(expr) |
| 87 | self.assertEqual(type(t), ast.Module) |
| 88 | self.assertEqual(len(t.body), 2) |
| 89 | # check `a = 10` |
| 90 | self.assertEqual(type(t.body[0]), ast.Assign) |
| 91 | self.assertEqual(t.body[0].lineno, 2) |
| 92 | # check `f'...'` |
| 93 | self.assertEqual(type(t.body[1]), ast.Expr) |
| 94 | self.assertEqual(type(t.body[1].value), ast.JoinedStr) |
| 95 | self.assertEqual(len(t.body[1].value.values), 1) |
| 96 | self.assertEqual(type(t.body[1].value.values[0]), ast.FormattedValue) |
| 97 | self.assertEqual(t.body[1].lineno, 3) |
| 98 | self.assertEqual(t.body[1].value.lineno, 3) |
| 99 | self.assertEqual(t.body[1].value.values[0].lineno, 3) |
| 100 | # check the binop location |
| 101 | binop = t.body[1].value.values[0].value |
| 102 | self.assertEqual(type(binop), ast.BinOp) |
| 103 | self.assertEqual(type(binop.left), ast.Name) |
| 104 | self.assertEqual(type(binop.op), ast.Mult) |
| 105 | self.assertEqual(type(binop.right), ast.Call) |
| 106 | self.assertEqual(binop.lineno, 3) |
| 107 | self.assertEqual(binop.left.lineno, 3) |
| 108 | self.assertEqual(binop.right.lineno, 3) |
| 109 | self.assertEqual(binop.col_offset, 3) |
| 110 | self.assertEqual(binop.left.col_offset, 3) |
| 111 | self.assertEqual(binop.right.col_offset, 7) |
| 112 | |
| 113 | def test_ast_line_numbers_multiple_formattedvalues(self): |
| 114 | expr = """ |
| 115 | f'no formatted values' |
| 116 | f'eggs {a * x()} spam {b + y()}'""" |
| 117 | t = ast.parse(expr) |
| 118 | self.assertEqual(type(t), ast.Module) |
| 119 | self.assertEqual(len(t.body), 2) |
| 120 | # check `f'no formatted value'` |
| 121 | self.assertEqual(type(t.body[0]), ast.Expr) |
| 122 | self.assertEqual(type(t.body[0].value), ast.JoinedStr) |
| 123 | self.assertEqual(t.body[0].lineno, 2) |
| 124 | # check `f'...'` |
| 125 | self.assertEqual(type(t.body[1]), ast.Expr) |
| 126 | self.assertEqual(type(t.body[1].value), ast.JoinedStr) |
| 127 | self.assertEqual(len(t.body[1].value.values), 4) |
Serhiy Storchaka | 3f22811 | 2018-09-27 17:42:37 +0300 | [diff] [blame] | 128 | self.assertEqual(type(t.body[1].value.values[0]), ast.Constant) |
| 129 | self.assertEqual(type(t.body[1].value.values[0].value), str) |
Łukasz Langa | e7c566c | 2017-09-06 17:27:58 -0700 | [diff] [blame] | 130 | self.assertEqual(type(t.body[1].value.values[1]), ast.FormattedValue) |
Serhiy Storchaka | 3f22811 | 2018-09-27 17:42:37 +0300 | [diff] [blame] | 131 | self.assertEqual(type(t.body[1].value.values[2]), ast.Constant) |
| 132 | self.assertEqual(type(t.body[1].value.values[2].value), str) |
Łukasz Langa | e7c566c | 2017-09-06 17:27:58 -0700 | [diff] [blame] | 133 | self.assertEqual(type(t.body[1].value.values[3]), ast.FormattedValue) |
| 134 | self.assertEqual(t.body[1].lineno, 3) |
| 135 | self.assertEqual(t.body[1].value.lineno, 3) |
| 136 | self.assertEqual(t.body[1].value.values[0].lineno, 3) |
| 137 | self.assertEqual(t.body[1].value.values[1].lineno, 3) |
| 138 | self.assertEqual(t.body[1].value.values[2].lineno, 3) |
| 139 | self.assertEqual(t.body[1].value.values[3].lineno, 3) |
| 140 | # check the first binop location |
| 141 | binop1 = t.body[1].value.values[1].value |
| 142 | self.assertEqual(type(binop1), ast.BinOp) |
| 143 | self.assertEqual(type(binop1.left), ast.Name) |
| 144 | self.assertEqual(type(binop1.op), ast.Mult) |
| 145 | self.assertEqual(type(binop1.right), ast.Call) |
| 146 | self.assertEqual(binop1.lineno, 3) |
| 147 | self.assertEqual(binop1.left.lineno, 3) |
| 148 | self.assertEqual(binop1.right.lineno, 3) |
| 149 | self.assertEqual(binop1.col_offset, 8) |
| 150 | self.assertEqual(binop1.left.col_offset, 8) |
| 151 | self.assertEqual(binop1.right.col_offset, 12) |
| 152 | # check the second binop location |
| 153 | binop2 = t.body[1].value.values[3].value |
| 154 | self.assertEqual(type(binop2), ast.BinOp) |
| 155 | self.assertEqual(type(binop2.left), ast.Name) |
| 156 | self.assertEqual(type(binop2.op), ast.Add) |
| 157 | self.assertEqual(type(binop2.right), ast.Call) |
| 158 | self.assertEqual(binop2.lineno, 3) |
| 159 | self.assertEqual(binop2.left.lineno, 3) |
| 160 | self.assertEqual(binop2.right.lineno, 3) |
| 161 | self.assertEqual(binop2.col_offset, 23) |
| 162 | self.assertEqual(binop2.left.col_offset, 23) |
| 163 | self.assertEqual(binop2.right.col_offset, 27) |
| 164 | |
| 165 | def test_ast_line_numbers_nested(self): |
| 166 | expr = """ |
| 167 | a = 10 |
| 168 | f'{a * f"-{x()}-"}'""" |
| 169 | t = ast.parse(expr) |
| 170 | self.assertEqual(type(t), ast.Module) |
| 171 | self.assertEqual(len(t.body), 2) |
| 172 | # check `a = 10` |
| 173 | self.assertEqual(type(t.body[0]), ast.Assign) |
| 174 | self.assertEqual(t.body[0].lineno, 2) |
| 175 | # check `f'...'` |
| 176 | self.assertEqual(type(t.body[1]), ast.Expr) |
| 177 | self.assertEqual(type(t.body[1].value), ast.JoinedStr) |
| 178 | self.assertEqual(len(t.body[1].value.values), 1) |
| 179 | self.assertEqual(type(t.body[1].value.values[0]), ast.FormattedValue) |
| 180 | self.assertEqual(t.body[1].lineno, 3) |
| 181 | self.assertEqual(t.body[1].value.lineno, 3) |
| 182 | self.assertEqual(t.body[1].value.values[0].lineno, 3) |
| 183 | # check the binop location |
| 184 | binop = t.body[1].value.values[0].value |
| 185 | self.assertEqual(type(binop), ast.BinOp) |
| 186 | self.assertEqual(type(binop.left), ast.Name) |
| 187 | self.assertEqual(type(binop.op), ast.Mult) |
| 188 | self.assertEqual(type(binop.right), ast.JoinedStr) |
| 189 | self.assertEqual(binop.lineno, 3) |
| 190 | self.assertEqual(binop.left.lineno, 3) |
| 191 | self.assertEqual(binop.right.lineno, 3) |
| 192 | self.assertEqual(binop.col_offset, 3) |
| 193 | self.assertEqual(binop.left.col_offset, 3) |
| 194 | self.assertEqual(binop.right.col_offset, 7) |
| 195 | # check the nested call location |
| 196 | self.assertEqual(len(binop.right.values), 3) |
Serhiy Storchaka | 3f22811 | 2018-09-27 17:42:37 +0300 | [diff] [blame] | 197 | self.assertEqual(type(binop.right.values[0]), ast.Constant) |
| 198 | self.assertEqual(type(binop.right.values[0].value), str) |
Łukasz Langa | e7c566c | 2017-09-06 17:27:58 -0700 | [diff] [blame] | 199 | self.assertEqual(type(binop.right.values[1]), ast.FormattedValue) |
Serhiy Storchaka | 3f22811 | 2018-09-27 17:42:37 +0300 | [diff] [blame] | 200 | self.assertEqual(type(binop.right.values[2]), ast.Constant) |
| 201 | self.assertEqual(type(binop.right.values[2].value), str) |
Łukasz Langa | e7c566c | 2017-09-06 17:27:58 -0700 | [diff] [blame] | 202 | self.assertEqual(binop.right.values[0].lineno, 3) |
| 203 | self.assertEqual(binop.right.values[1].lineno, 3) |
| 204 | self.assertEqual(binop.right.values[2].lineno, 3) |
| 205 | call = binop.right.values[1].value |
| 206 | self.assertEqual(type(call), ast.Call) |
| 207 | self.assertEqual(call.lineno, 3) |
| 208 | self.assertEqual(call.col_offset, 11) |
| 209 | |
| 210 | def test_ast_line_numbers_duplicate_expression(self): |
| 211 | """Duplicate expression |
| 212 | |
| 213 | NOTE: this is currently broken, always sets location of the first |
| 214 | expression. |
| 215 | """ |
| 216 | expr = """ |
| 217 | a = 10 |
| 218 | f'{a * x()} {a * x()} {a * x()}' |
| 219 | """ |
| 220 | t = ast.parse(expr) |
| 221 | self.assertEqual(type(t), ast.Module) |
| 222 | self.assertEqual(len(t.body), 2) |
| 223 | # check `a = 10` |
| 224 | self.assertEqual(type(t.body[0]), ast.Assign) |
| 225 | self.assertEqual(t.body[0].lineno, 2) |
| 226 | # check `f'...'` |
| 227 | self.assertEqual(type(t.body[1]), ast.Expr) |
| 228 | self.assertEqual(type(t.body[1].value), ast.JoinedStr) |
| 229 | self.assertEqual(len(t.body[1].value.values), 5) |
| 230 | self.assertEqual(type(t.body[1].value.values[0]), ast.FormattedValue) |
Serhiy Storchaka | 3f22811 | 2018-09-27 17:42:37 +0300 | [diff] [blame] | 231 | self.assertEqual(type(t.body[1].value.values[1]), ast.Constant) |
| 232 | self.assertEqual(type(t.body[1].value.values[1].value), str) |
Łukasz Langa | e7c566c | 2017-09-06 17:27:58 -0700 | [diff] [blame] | 233 | self.assertEqual(type(t.body[1].value.values[2]), ast.FormattedValue) |
Serhiy Storchaka | 3f22811 | 2018-09-27 17:42:37 +0300 | [diff] [blame] | 234 | self.assertEqual(type(t.body[1].value.values[3]), ast.Constant) |
| 235 | self.assertEqual(type(t.body[1].value.values[3].value), str) |
Łukasz Langa | e7c566c | 2017-09-06 17:27:58 -0700 | [diff] [blame] | 236 | self.assertEqual(type(t.body[1].value.values[4]), ast.FormattedValue) |
| 237 | self.assertEqual(t.body[1].lineno, 3) |
| 238 | self.assertEqual(t.body[1].value.lineno, 3) |
| 239 | self.assertEqual(t.body[1].value.values[0].lineno, 3) |
| 240 | self.assertEqual(t.body[1].value.values[1].lineno, 3) |
| 241 | self.assertEqual(t.body[1].value.values[2].lineno, 3) |
| 242 | self.assertEqual(t.body[1].value.values[3].lineno, 3) |
| 243 | self.assertEqual(t.body[1].value.values[4].lineno, 3) |
| 244 | # check the first binop location |
| 245 | binop = t.body[1].value.values[0].value |
| 246 | self.assertEqual(type(binop), ast.BinOp) |
| 247 | self.assertEqual(type(binop.left), ast.Name) |
| 248 | self.assertEqual(type(binop.op), ast.Mult) |
| 249 | self.assertEqual(type(binop.right), ast.Call) |
| 250 | self.assertEqual(binop.lineno, 3) |
| 251 | self.assertEqual(binop.left.lineno, 3) |
| 252 | self.assertEqual(binop.right.lineno, 3) |
| 253 | self.assertEqual(binop.col_offset, 3) |
| 254 | self.assertEqual(binop.left.col_offset, 3) |
| 255 | self.assertEqual(binop.right.col_offset, 7) |
| 256 | # check the second binop location |
| 257 | binop = t.body[1].value.values[2].value |
| 258 | self.assertEqual(type(binop), ast.BinOp) |
| 259 | self.assertEqual(type(binop.left), ast.Name) |
| 260 | self.assertEqual(type(binop.op), ast.Mult) |
| 261 | self.assertEqual(type(binop.right), ast.Call) |
| 262 | self.assertEqual(binop.lineno, 3) |
| 263 | self.assertEqual(binop.left.lineno, 3) |
| 264 | self.assertEqual(binop.right.lineno, 3) |
| 265 | self.assertEqual(binop.col_offset, 3) # FIXME: this is wrong |
| 266 | self.assertEqual(binop.left.col_offset, 3) # FIXME: this is wrong |
| 267 | self.assertEqual(binop.right.col_offset, 7) # FIXME: this is wrong |
| 268 | # check the third binop location |
| 269 | binop = t.body[1].value.values[4].value |
| 270 | self.assertEqual(type(binop), ast.BinOp) |
| 271 | self.assertEqual(type(binop.left), ast.Name) |
| 272 | self.assertEqual(type(binop.op), ast.Mult) |
| 273 | self.assertEqual(type(binop.right), ast.Call) |
| 274 | self.assertEqual(binop.lineno, 3) |
| 275 | self.assertEqual(binop.left.lineno, 3) |
| 276 | self.assertEqual(binop.right.lineno, 3) |
| 277 | self.assertEqual(binop.col_offset, 3) # FIXME: this is wrong |
| 278 | self.assertEqual(binop.left.col_offset, 3) # FIXME: this is wrong |
| 279 | self.assertEqual(binop.right.col_offset, 7) # FIXME: this is wrong |
| 280 | |
| 281 | def test_ast_line_numbers_multiline_fstring(self): |
Anthony Sottile | 995d9b9 | 2019-01-12 20:05:13 -0800 | [diff] [blame] | 282 | # See bpo-30465 for details. |
Łukasz Langa | e7c566c | 2017-09-06 17:27:58 -0700 | [diff] [blame] | 283 | expr = """ |
| 284 | a = 10 |
| 285 | f''' |
| 286 | {a |
| 287 | * |
| 288 | x()} |
| 289 | non-important content |
| 290 | ''' |
| 291 | """ |
| 292 | t = ast.parse(expr) |
| 293 | self.assertEqual(type(t), ast.Module) |
| 294 | self.assertEqual(len(t.body), 2) |
| 295 | # check `a = 10` |
| 296 | self.assertEqual(type(t.body[0]), ast.Assign) |
| 297 | self.assertEqual(t.body[0].lineno, 2) |
| 298 | # check `f'...'` |
| 299 | self.assertEqual(type(t.body[1]), ast.Expr) |
| 300 | self.assertEqual(type(t.body[1].value), ast.JoinedStr) |
| 301 | self.assertEqual(len(t.body[1].value.values), 3) |
Serhiy Storchaka | 3f22811 | 2018-09-27 17:42:37 +0300 | [diff] [blame] | 302 | self.assertEqual(type(t.body[1].value.values[0]), ast.Constant) |
| 303 | self.assertEqual(type(t.body[1].value.values[0].value), str) |
Łukasz Langa | e7c566c | 2017-09-06 17:27:58 -0700 | [diff] [blame] | 304 | self.assertEqual(type(t.body[1].value.values[1]), ast.FormattedValue) |
Serhiy Storchaka | 3f22811 | 2018-09-27 17:42:37 +0300 | [diff] [blame] | 305 | self.assertEqual(type(t.body[1].value.values[2]), ast.Constant) |
| 306 | self.assertEqual(type(t.body[1].value.values[2].value), str) |
Anthony Sottile | 995d9b9 | 2019-01-12 20:05:13 -0800 | [diff] [blame] | 307 | self.assertEqual(t.body[1].lineno, 3) |
| 308 | self.assertEqual(t.body[1].value.lineno, 3) |
| 309 | self.assertEqual(t.body[1].value.values[0].lineno, 3) |
| 310 | self.assertEqual(t.body[1].value.values[1].lineno, 3) |
| 311 | self.assertEqual(t.body[1].value.values[2].lineno, 3) |
| 312 | self.assertEqual(t.body[1].col_offset, 0) |
| 313 | self.assertEqual(t.body[1].value.col_offset, 0) |
| 314 | self.assertEqual(t.body[1].value.values[0].col_offset, 0) |
| 315 | self.assertEqual(t.body[1].value.values[1].col_offset, 0) |
| 316 | self.assertEqual(t.body[1].value.values[2].col_offset, 0) |
Łukasz Langa | e7c566c | 2017-09-06 17:27:58 -0700 | [diff] [blame] | 317 | # NOTE: the following lineno information and col_offset is correct for |
| 318 | # expressions within FormattedValues. |
| 319 | binop = t.body[1].value.values[1].value |
| 320 | self.assertEqual(type(binop), ast.BinOp) |
| 321 | self.assertEqual(type(binop.left), ast.Name) |
| 322 | self.assertEqual(type(binop.op), ast.Mult) |
| 323 | self.assertEqual(type(binop.right), ast.Call) |
| 324 | self.assertEqual(binop.lineno, 4) |
| 325 | self.assertEqual(binop.left.lineno, 4) |
| 326 | self.assertEqual(binop.right.lineno, 6) |
Anthony Sottile | 995d9b9 | 2019-01-12 20:05:13 -0800 | [diff] [blame] | 327 | self.assertEqual(binop.col_offset, 4) |
| 328 | self.assertEqual(binop.left.col_offset, 4) |
Łukasz Langa | e7c566c | 2017-09-06 17:27:58 -0700 | [diff] [blame] | 329 | self.assertEqual(binop.right.col_offset, 7) |
| 330 | |
Serhiy Storchaka | 4cc30ae | 2016-12-11 19:37:19 +0200 | [diff] [blame] | 331 | def test_docstring(self): |
| 332 | def f(): |
| 333 | f'''Not a docstring''' |
| 334 | self.assertIsNone(f.__doc__) |
| 335 | def g(): |
| 336 | '''Not a docstring''' \ |
| 337 | f'' |
| 338 | self.assertIsNone(g.__doc__) |
| 339 | |
Eric V. Smith | 235a6f0 | 2015-09-19 14:51:32 -0400 | [diff] [blame] | 340 | def test_literal_eval(self): |
Eric V. Smith | 235a6f0 | 2015-09-19 14:51:32 -0400 | [diff] [blame] | 341 | with self.assertRaisesRegex(ValueError, 'malformed node or string'): |
Serhiy Storchaka | 4cc30ae | 2016-12-11 19:37:19 +0200 | [diff] [blame] | 342 | ast.literal_eval("f'x'") |
Eric V. Smith | 235a6f0 | 2015-09-19 14:51:32 -0400 | [diff] [blame] | 343 | |
| 344 | def test_ast_compile_time_concat(self): |
| 345 | x = [''] |
| 346 | |
| 347 | expr = """x[0] = 'foo' f'{3}'""" |
| 348 | t = ast.parse(expr) |
| 349 | c = compile(t, '', 'exec') |
| 350 | exec(c) |
| 351 | self.assertEqual(x[0], 'foo3') |
| 352 | |
Eric V. Smith | 9b88fdf | 2016-11-07 17:54:01 -0500 | [diff] [blame] | 353 | def test_compile_time_concat_errors(self): |
| 354 | self.assertAllRaise(SyntaxError, |
| 355 | 'cannot mix bytes and nonbytes literals', |
| 356 | [r"""f'' b''""", |
| 357 | r"""b'' f''""", |
| 358 | ]) |
| 359 | |
Eric V. Smith | 235a6f0 | 2015-09-19 14:51:32 -0400 | [diff] [blame] | 360 | def test_literal(self): |
| 361 | self.assertEqual(f'', '') |
| 362 | self.assertEqual(f'a', 'a') |
| 363 | self.assertEqual(f' ', ' ') |
Eric V. Smith | 235a6f0 | 2015-09-19 14:51:32 -0400 | [diff] [blame] | 364 | |
| 365 | def test_unterminated_string(self): |
| 366 | self.assertAllRaise(SyntaxError, 'f-string: unterminated string', |
| 367 | [r"""f'{"x'""", |
| 368 | r"""f'{"x}'""", |
| 369 | r"""f'{("x'""", |
| 370 | r"""f'{("x}'""", |
| 371 | ]) |
| 372 | |
| 373 | def test_mismatched_parens(self): |
Serhiy Storchaka | 58159ef | 2019-01-12 09:46:50 +0200 | [diff] [blame] | 374 | self.assertAllRaise(SyntaxError, r"f-string: closing parenthesis '\}' " |
| 375 | r"does not match opening parenthesis '\('", |
Eric V. Smith | 235a6f0 | 2015-09-19 14:51:32 -0400 | [diff] [blame] | 376 | ["f'{((}'", |
| 377 | ]) |
Serhiy Storchaka | 58159ef | 2019-01-12 09:46:50 +0200 | [diff] [blame] | 378 | self.assertAllRaise(SyntaxError, r"f-string: closing parenthesis '\)' " |
| 379 | r"does not match opening parenthesis '\['", |
| 380 | ["f'{a[4)}'", |
| 381 | ]) |
| 382 | self.assertAllRaise(SyntaxError, r"f-string: closing parenthesis '\]' " |
| 383 | r"does not match opening parenthesis '\('", |
| 384 | ["f'{a(4]}'", |
| 385 | ]) |
| 386 | self.assertAllRaise(SyntaxError, r"f-string: closing parenthesis '\}' " |
| 387 | r"does not match opening parenthesis '\['", |
| 388 | ["f'{a[4}'", |
| 389 | ]) |
| 390 | self.assertAllRaise(SyntaxError, r"f-string: closing parenthesis '\}' " |
| 391 | r"does not match opening parenthesis '\('", |
| 392 | ["f'{a(4}'", |
| 393 | ]) |
| 394 | self.assertRaises(SyntaxError, eval, "f'{" + "("*500 + "}'") |
Eric V. Smith | 235a6f0 | 2015-09-19 14:51:32 -0400 | [diff] [blame] | 395 | |
| 396 | def test_double_braces(self): |
| 397 | self.assertEqual(f'{{', '{') |
| 398 | self.assertEqual(f'a{{', 'a{') |
| 399 | self.assertEqual(f'{{b', '{b') |
| 400 | self.assertEqual(f'a{{b', 'a{b') |
| 401 | self.assertEqual(f'}}', '}') |
| 402 | self.assertEqual(f'a}}', 'a}') |
| 403 | self.assertEqual(f'}}b', '}b') |
| 404 | self.assertEqual(f'a}}b', 'a}b') |
Eric V. Smith | 451d0e3 | 2016-09-09 21:56:20 -0400 | [diff] [blame] | 405 | self.assertEqual(f'{{}}', '{}') |
| 406 | self.assertEqual(f'a{{}}', 'a{}') |
| 407 | self.assertEqual(f'{{b}}', '{b}') |
| 408 | self.assertEqual(f'{{}}c', '{}c') |
| 409 | self.assertEqual(f'a{{b}}', 'a{b}') |
| 410 | self.assertEqual(f'a{{}}c', 'a{}c') |
| 411 | self.assertEqual(f'{{b}}c', '{b}c') |
| 412 | self.assertEqual(f'a{{b}}c', 'a{b}c') |
Eric V. Smith | 235a6f0 | 2015-09-19 14:51:32 -0400 | [diff] [blame] | 413 | |
| 414 | self.assertEqual(f'{{{10}', '{10') |
| 415 | self.assertEqual(f'}}{10}', '}10') |
| 416 | self.assertEqual(f'}}{{{10}', '}{10') |
| 417 | self.assertEqual(f'}}a{{{10}', '}a{10') |
| 418 | |
| 419 | self.assertEqual(f'{10}{{', '10{') |
| 420 | self.assertEqual(f'{10}}}', '10}') |
| 421 | self.assertEqual(f'{10}}}{{', '10}{') |
| 422 | self.assertEqual(f'{10}}}a{{' '}', '10}a{}') |
| 423 | |
| 424 | # Inside of strings, don't interpret doubled brackets. |
| 425 | self.assertEqual(f'{"{{}}"}', '{{}}') |
| 426 | |
| 427 | self.assertAllRaise(TypeError, 'unhashable type', |
| 428 | ["f'{ {{}} }'", # dict in a set |
| 429 | ]) |
| 430 | |
| 431 | def test_compile_time_concat(self): |
| 432 | x = 'def' |
| 433 | self.assertEqual('abc' f'## {x}ghi', 'abc## defghi') |
| 434 | self.assertEqual('abc' f'{x}' 'ghi', 'abcdefghi') |
| 435 | self.assertEqual('abc' f'{x}' 'gh' f'i{x:4}', 'abcdefghidef ') |
| 436 | self.assertEqual('{x}' f'{x}', '{x}def') |
| 437 | self.assertEqual('{x' f'{x}', '{xdef') |
| 438 | self.assertEqual('{x}' f'{x}', '{x}def') |
| 439 | self.assertEqual('{{x}}' f'{x}', '{{x}}def') |
| 440 | self.assertEqual('{{x' f'{x}', '{{xdef') |
| 441 | self.assertEqual('x}}' f'{x}', 'x}}def') |
| 442 | self.assertEqual(f'{x}' 'x}}', 'defx}}') |
| 443 | self.assertEqual(f'{x}' '', 'def') |
| 444 | self.assertEqual('' f'{x}' '', 'def') |
| 445 | self.assertEqual('' f'{x}', 'def') |
| 446 | self.assertEqual(f'{x}' '2', 'def2') |
| 447 | self.assertEqual('1' f'{x}' '2', '1def2') |
| 448 | self.assertEqual('1' f'{x}', '1def') |
| 449 | self.assertEqual(f'{x}' f'-{x}', 'def-def') |
| 450 | self.assertEqual('' f'', '') |
| 451 | self.assertEqual('' f'' '', '') |
| 452 | self.assertEqual('' f'' '' f'', '') |
| 453 | self.assertEqual(f'', '') |
| 454 | self.assertEqual(f'' '', '') |
| 455 | self.assertEqual(f'' '' f'', '') |
| 456 | self.assertEqual(f'' '' f'' '', '') |
| 457 | |
| 458 | self.assertAllRaise(SyntaxError, "f-string: expecting '}'", |
| 459 | ["f'{3' f'}'", # can't concat to get a valid f-string |
| 460 | ]) |
| 461 | |
| 462 | def test_comments(self): |
| 463 | # These aren't comments, since they're in strings. |
| 464 | d = {'#': 'hash'} |
| 465 | self.assertEqual(f'{"#"}', '#') |
| 466 | self.assertEqual(f'{d["#"]}', 'hash') |
| 467 | |
Eric V. Smith | 09835dc | 2016-09-11 18:58:20 -0400 | [diff] [blame] | 468 | self.assertAllRaise(SyntaxError, "f-string expression part cannot include '#'", |
Eric V. Smith | 235a6f0 | 2015-09-19 14:51:32 -0400 | [diff] [blame] | 469 | ["f'{1#}'", # error because the expression becomes "(1#)" |
| 470 | "f'{3(#)}'", |
Eric V. Smith | 09835dc | 2016-09-11 18:58:20 -0400 | [diff] [blame] | 471 | "f'{#}'", |
Serhiy Storchaka | 58159ef | 2019-01-12 09:46:50 +0200 | [diff] [blame] | 472 | ]) |
| 473 | self.assertAllRaise(SyntaxError, r"f-string: unmatched '\)'", |
| 474 | ["f'{)#}'", # When wrapped in parens, this becomes |
Eric V. Smith | 35a24c5 | 2016-09-11 19:01:22 -0400 | [diff] [blame] | 475 | # '()#)'. Make sure that doesn't compile. |
Eric V. Smith | 235a6f0 | 2015-09-19 14:51:32 -0400 | [diff] [blame] | 476 | ]) |
| 477 | |
| 478 | def test_many_expressions(self): |
| 479 | # Create a string with many expressions in it. Note that |
| 480 | # because we have a space in here as a literal, we're actually |
| 481 | # going to use twice as many ast nodes: one for each literal |
| 482 | # plus one for each expression. |
| 483 | def build_fstr(n, extra=''): |
| 484 | return "f'" + ('{x} ' * n) + extra + "'" |
| 485 | |
| 486 | x = 'X' |
| 487 | width = 1 |
| 488 | |
| 489 | # Test around 256. |
| 490 | for i in range(250, 260): |
| 491 | self.assertEqual(eval(build_fstr(i)), (x+' ')*i) |
| 492 | |
| 493 | # Test concatenating 2 largs fstrings. |
| 494 | self.assertEqual(eval(build_fstr(255)*256), (x+' ')*(255*256)) |
| 495 | |
| 496 | s = build_fstr(253, '{x:{width}} ') |
| 497 | self.assertEqual(eval(s), (x+' ')*254) |
| 498 | |
| 499 | # Test lots of expressions and constants, concatenated. |
| 500 | s = "f'{1}' 'x' 'y'" * 1024 |
| 501 | self.assertEqual(eval(s), '1xy' * 1024) |
| 502 | |
| 503 | def test_format_specifier_expressions(self): |
| 504 | width = 10 |
| 505 | precision = 4 |
| 506 | value = decimal.Decimal('12.34567') |
| 507 | self.assertEqual(f'result: {value:{width}.{precision}}', 'result: 12.35') |
| 508 | self.assertEqual(f'result: {value:{width!r}.{precision}}', 'result: 12.35') |
| 509 | self.assertEqual(f'result: {value:{width:0}.{precision:1}}', 'result: 12.35') |
| 510 | self.assertEqual(f'result: {value:{1}{0:0}.{precision:1}}', 'result: 12.35') |
| 511 | self.assertEqual(f'result: {value:{ 1}{ 0:0}.{ precision:1}}', 'result: 12.35') |
| 512 | self.assertEqual(f'{10:#{1}0x}', ' 0xa') |
| 513 | self.assertEqual(f'{10:{"#"}1{0}{"x"}}', ' 0xa') |
| 514 | self.assertEqual(f'{-10:-{"#"}1{0}x}', ' -0xa') |
| 515 | self.assertEqual(f'{-10:{"-"}#{1}0{"x"}}', ' -0xa') |
| 516 | self.assertEqual(f'{10:#{3 != {4:5} and width}x}', ' 0xa') |
| 517 | |
| 518 | self.assertAllRaise(SyntaxError, "f-string: expecting '}'", |
| 519 | ["""f'{"s"!r{":10"}}'""", |
| 520 | |
| 521 | # This looks like a nested format spec. |
| 522 | ]) |
| 523 | |
| 524 | self.assertAllRaise(SyntaxError, "invalid syntax", |
Martin Panter | 263893c | 2016-07-28 01:25:31 +0000 | [diff] [blame] | 525 | [# Invalid syntax inside a nested spec. |
Eric V. Smith | 235a6f0 | 2015-09-19 14:51:32 -0400 | [diff] [blame] | 526 | "f'{4:{/5}}'", |
| 527 | ]) |
| 528 | |
| 529 | self.assertAllRaise(SyntaxError, "f-string: expressions nested too deeply", |
| 530 | [# Can't nest format specifiers. |
| 531 | "f'result: {value:{width:{0}}.{precision:1}}'", |
| 532 | ]) |
| 533 | |
| 534 | self.assertAllRaise(SyntaxError, 'f-string: invalid conversion character', |
| 535 | [# No expansion inside conversion or for |
| 536 | # the : or ! itself. |
| 537 | """f'{"s"!{"r"}}'""", |
| 538 | ]) |
| 539 | |
| 540 | def test_side_effect_order(self): |
| 541 | class X: |
| 542 | def __init__(self): |
| 543 | self.i = 0 |
| 544 | def __format__(self, spec): |
| 545 | self.i += 1 |
| 546 | return str(self.i) |
| 547 | |
| 548 | x = X() |
| 549 | self.assertEqual(f'{x} {x}', '1 2') |
| 550 | |
| 551 | def test_missing_expression(self): |
| 552 | self.assertAllRaise(SyntaxError, 'f-string: empty expression not allowed', |
| 553 | ["f'{}'", |
| 554 | "f'{ }'" |
| 555 | "f' {} '", |
| 556 | "f'{!r}'", |
| 557 | "f'{ !r}'", |
| 558 | "f'{10:{ }}'", |
| 559 | "f' { } '", |
Eric V. Smith | 1d44c41 | 2015-09-23 07:49:00 -0400 | [diff] [blame] | 560 | |
Serhiy Storchaka | 2e9cd58 | 2017-06-08 23:43:54 +0300 | [diff] [blame] | 561 | # The Python parser ignores also the following |
| 562 | # whitespace characters in additional to a space. |
| 563 | "f'''{\t\f\r\n}'''", |
| 564 | |
Eric V. Smith | 1d44c41 | 2015-09-23 07:49:00 -0400 | [diff] [blame] | 565 | # Catch the empty expression before the |
| 566 | # invalid conversion. |
| 567 | "f'{!x}'", |
| 568 | "f'{ !xr}'", |
| 569 | "f'{!x:}'", |
| 570 | "f'{!x:a}'", |
| 571 | "f'{ !xr:}'", |
| 572 | "f'{ !xr:a}'", |
Eric V. Smith | 548c4d3 | 2015-09-23 08:00:01 -0400 | [diff] [blame] | 573 | |
| 574 | "f'{!}'", |
| 575 | "f'{:}'", |
Eric V. Smith | b2080f6 | 2015-09-23 10:24:43 -0400 | [diff] [blame] | 576 | |
| 577 | # We find the empty expression before the |
| 578 | # missing closing brace. |
| 579 | "f'{!'", |
| 580 | "f'{!s:'", |
| 581 | "f'{:'", |
| 582 | "f'{:x'", |
Eric V. Smith | 235a6f0 | 2015-09-19 14:51:32 -0400 | [diff] [blame] | 583 | ]) |
| 584 | |
Serhiy Storchaka | 2e9cd58 | 2017-06-08 23:43:54 +0300 | [diff] [blame] | 585 | # Different error message is raised for other whitespace characters. |
| 586 | self.assertAllRaise(SyntaxError, 'invalid character in identifier', |
| 587 | ["f'''{\xa0}'''", |
| 588 | "\xa0", |
| 589 | ]) |
| 590 | |
Eric V. Smith | 235a6f0 | 2015-09-19 14:51:32 -0400 | [diff] [blame] | 591 | def test_parens_in_expressions(self): |
| 592 | self.assertEqual(f'{3,}', '(3,)') |
| 593 | |
| 594 | # Add these because when an expression is evaluated, parens |
| 595 | # are added around it. But we shouldn't go from an invalid |
| 596 | # expression to a valid one. The added parens are just |
| 597 | # supposed to allow whitespace (including newlines). |
| 598 | self.assertAllRaise(SyntaxError, 'invalid syntax', |
| 599 | ["f'{,}'", |
| 600 | "f'{,}'", # this is (,), which is an error |
| 601 | ]) |
| 602 | |
Serhiy Storchaka | 58159ef | 2019-01-12 09:46:50 +0200 | [diff] [blame] | 603 | self.assertAllRaise(SyntaxError, r"f-string: unmatched '\)'", |
Eric V. Smith | 235a6f0 | 2015-09-19 14:51:32 -0400 | [diff] [blame] | 604 | ["f'{3)+(4}'", |
| 605 | ]) |
| 606 | |
| 607 | self.assertAllRaise(SyntaxError, 'EOL while scanning string literal', |
| 608 | ["f'{\n}'", |
| 609 | ]) |
| 610 | |
Eric V. Smith | 451d0e3 | 2016-09-09 21:56:20 -0400 | [diff] [blame] | 611 | def test_backslashes_in_string_part(self): |
| 612 | self.assertEqual(f'\t', '\t') |
| 613 | self.assertEqual(r'\t', '\\t') |
| 614 | self.assertEqual(rf'\t', '\\t') |
| 615 | self.assertEqual(f'{2}\t', '2\t') |
| 616 | self.assertEqual(f'{2}\t{3}', '2\t3') |
| 617 | self.assertEqual(f'\t{3}', '\t3') |
Eric V. Smith | 6a4efce | 2016-09-03 09:18:34 -0400 | [diff] [blame] | 618 | |
Eric V. Smith | 451d0e3 | 2016-09-09 21:56:20 -0400 | [diff] [blame] | 619 | self.assertEqual(f'\u0394', '\u0394') |
| 620 | self.assertEqual(r'\u0394', '\\u0394') |
| 621 | self.assertEqual(rf'\u0394', '\\u0394') |
| 622 | self.assertEqual(f'{2}\u0394', '2\u0394') |
| 623 | self.assertEqual(f'{2}\u0394{3}', '2\u03943') |
| 624 | self.assertEqual(f'\u0394{3}', '\u03943') |
Eric V. Smith | 6a4efce | 2016-09-03 09:18:34 -0400 | [diff] [blame] | 625 | |
Eric V. Smith | 451d0e3 | 2016-09-09 21:56:20 -0400 | [diff] [blame] | 626 | self.assertEqual(f'\U00000394', '\u0394') |
| 627 | self.assertEqual(r'\U00000394', '\\U00000394') |
| 628 | self.assertEqual(rf'\U00000394', '\\U00000394') |
| 629 | self.assertEqual(f'{2}\U00000394', '2\u0394') |
| 630 | self.assertEqual(f'{2}\U00000394{3}', '2\u03943') |
| 631 | self.assertEqual(f'\U00000394{3}', '\u03943') |
Eric V. Smith | 6a4efce | 2016-09-03 09:18:34 -0400 | [diff] [blame] | 632 | |
Eric V. Smith | 451d0e3 | 2016-09-09 21:56:20 -0400 | [diff] [blame] | 633 | self.assertEqual(f'\N{GREEK CAPITAL LETTER DELTA}', '\u0394') |
| 634 | self.assertEqual(f'{2}\N{GREEK CAPITAL LETTER DELTA}', '2\u0394') |
| 635 | self.assertEqual(f'{2}\N{GREEK CAPITAL LETTER DELTA}{3}', '2\u03943') |
| 636 | self.assertEqual(f'\N{GREEK CAPITAL LETTER DELTA}{3}', '\u03943') |
| 637 | self.assertEqual(f'2\N{GREEK CAPITAL LETTER DELTA}', '2\u0394') |
| 638 | self.assertEqual(f'2\N{GREEK CAPITAL LETTER DELTA}3', '2\u03943') |
| 639 | self.assertEqual(f'\N{GREEK CAPITAL LETTER DELTA}3', '\u03943') |
Eric V. Smith | 6a4efce | 2016-09-03 09:18:34 -0400 | [diff] [blame] | 640 | |
Eric V. Smith | 451d0e3 | 2016-09-09 21:56:20 -0400 | [diff] [blame] | 641 | self.assertEqual(f'\x20', ' ') |
| 642 | self.assertEqual(r'\x20', '\\x20') |
| 643 | self.assertEqual(rf'\x20', '\\x20') |
| 644 | self.assertEqual(f'{2}\x20', '2 ') |
| 645 | self.assertEqual(f'{2}\x20{3}', '2 3') |
| 646 | self.assertEqual(f'\x20{3}', ' 3') |
Eric V. Smith | 6a4efce | 2016-09-03 09:18:34 -0400 | [diff] [blame] | 647 | |
Eric V. Smith | 451d0e3 | 2016-09-09 21:56:20 -0400 | [diff] [blame] | 648 | self.assertEqual(f'2\x20', '2 ') |
| 649 | self.assertEqual(f'2\x203', '2 3') |
| 650 | self.assertEqual(f'\x203', ' 3') |
Eric V. Smith | 6a4efce | 2016-09-03 09:18:34 -0400 | [diff] [blame] | 651 | |
Serhiy Storchaka | 4c5b6ba | 2019-08-10 01:34:22 +0300 | [diff] [blame] | 652 | with self.assertWarns(DeprecationWarning): # invalid escape sequence |
Serhiy Storchaka | 0cd7a3f | 2017-05-25 13:33:55 +0300 | [diff] [blame] | 653 | value = eval(r"f'\{6*7}'") |
| 654 | self.assertEqual(value, '\\42') |
| 655 | self.assertEqual(f'\\{6*7}', '\\42') |
| 656 | self.assertEqual(fr'\{6*7}', '\\42') |
| 657 | |
| 658 | AMPERSAND = 'spam' |
| 659 | # Get the right unicode character (&), or pick up local variable |
| 660 | # depending on the number of backslashes. |
| 661 | self.assertEqual(f'\N{AMPERSAND}', '&') |
| 662 | self.assertEqual(f'\\N{AMPERSAND}', '\\Nspam') |
| 663 | self.assertEqual(fr'\N{AMPERSAND}', '\\Nspam') |
| 664 | self.assertEqual(f'\\\N{AMPERSAND}', '\\&') |
| 665 | |
Eric V. Smith | 451d0e3 | 2016-09-09 21:56:20 -0400 | [diff] [blame] | 666 | def test_misformed_unicode_character_name(self): |
| 667 | # These test are needed because unicode names are parsed |
| 668 | # differently inside f-strings. |
| 669 | self.assertAllRaise(SyntaxError, r"\(unicode error\) 'unicodeescape' codec can't decode bytes in position .*: malformed \\N character escape", |
| 670 | [r"f'\N'", |
| 671 | r"f'\N{'", |
| 672 | r"f'\N{GREEK CAPITAL LETTER DELTA'", |
| 673 | |
| 674 | # Here are the non-f-string versions, |
| 675 | # which should give the same errors. |
| 676 | r"'\N'", |
| 677 | r"'\N{'", |
| 678 | r"'\N{GREEK CAPITAL LETTER DELTA'", |
Eric V. Smith | 6a4efce | 2016-09-03 09:18:34 -0400 | [diff] [blame] | 679 | ]) |
| 680 | |
Eric V. Smith | 451d0e3 | 2016-09-09 21:56:20 -0400 | [diff] [blame] | 681 | def test_no_backslashes_in_expression_part(self): |
| 682 | self.assertAllRaise(SyntaxError, 'f-string expression part cannot include a backslash', |
Eric V. Smith | 6a4efce | 2016-09-03 09:18:34 -0400 | [diff] [blame] | 683 | [r"f'{\'a\'}'", |
| 684 | r"f'{\t3}'", |
Eric V. Smith | 451d0e3 | 2016-09-09 21:56:20 -0400 | [diff] [blame] | 685 | r"f'{\}'", |
| 686 | r"rf'{\'a\'}'", |
| 687 | r"rf'{\t3}'", |
| 688 | r"rf'{\}'", |
| 689 | r"""rf'{"\N{LEFT CURLY BRACKET}"}'""", |
Jason R. Coombs | 45cab8c | 2016-11-06 11:01:08 -0500 | [diff] [blame] | 690 | r"f'{\n}'", |
Eric V. Smith | 6a4efce | 2016-09-03 09:18:34 -0400 | [diff] [blame] | 691 | ]) |
| 692 | |
Eric V. Smith | 451d0e3 | 2016-09-09 21:56:20 -0400 | [diff] [blame] | 693 | def test_no_escapes_for_braces(self): |
Jason R. Coombs | 1c92a76 | 2016-11-06 11:25:54 -0500 | [diff] [blame] | 694 | """ |
| 695 | Only literal curly braces begin an expression. |
| 696 | """ |
| 697 | # \x7b is '{'. |
| 698 | self.assertEqual(f'\x7b1+1}}', '{1+1}') |
| 699 | self.assertEqual(f'\x7b1+1', '{1+1') |
| 700 | self.assertEqual(f'\u007b1+1', '{1+1') |
| 701 | self.assertEqual(f'\N{LEFT CURLY BRACKET}1+1\N{RIGHT CURLY BRACKET}', '{1+1}') |
Eric V. Smith | 6a4efce | 2016-09-03 09:18:34 -0400 | [diff] [blame] | 702 | |
Eric V. Smith | 235a6f0 | 2015-09-19 14:51:32 -0400 | [diff] [blame] | 703 | def test_newlines_in_expressions(self): |
| 704 | self.assertEqual(f'{0}', '0') |
Eric V. Smith | 235a6f0 | 2015-09-19 14:51:32 -0400 | [diff] [blame] | 705 | self.assertEqual(rf'''{3+ |
| 706 | 4}''', '7') |
Eric V. Smith | 235a6f0 | 2015-09-19 14:51:32 -0400 | [diff] [blame] | 707 | |
| 708 | def test_lambda(self): |
| 709 | x = 5 |
| 710 | self.assertEqual(f'{(lambda y:x*y)("8")!r}', "'88888'") |
| 711 | self.assertEqual(f'{(lambda y:x*y)("8")!r:10}', "'88888' ") |
| 712 | self.assertEqual(f'{(lambda y:x*y)("8"):10}', "88888 ") |
| 713 | |
| 714 | # lambda doesn't work without parens, because the colon |
| 715 | # makes the parser think it's a format_spec |
| 716 | self.assertAllRaise(SyntaxError, 'unexpected EOF while parsing', |
| 717 | ["f'{lambda x:x}'", |
| 718 | ]) |
| 719 | |
| 720 | def test_yield(self): |
| 721 | # Not terribly useful, but make sure the yield turns |
| 722 | # a function into a generator |
| 723 | def fn(y): |
| 724 | f'y:{yield y*2}' |
| 725 | |
| 726 | g = fn(4) |
| 727 | self.assertEqual(next(g), 8) |
| 728 | |
| 729 | def test_yield_send(self): |
| 730 | def fn(x): |
| 731 | yield f'x:{yield (lambda i: x * i)}' |
| 732 | |
| 733 | g = fn(10) |
| 734 | the_lambda = next(g) |
| 735 | self.assertEqual(the_lambda(4), 40) |
| 736 | self.assertEqual(g.send('string'), 'x:string') |
| 737 | |
| 738 | def test_expressions_with_triple_quoted_strings(self): |
| 739 | self.assertEqual(f"{'''x'''}", 'x') |
| 740 | self.assertEqual(f"{'''eric's'''}", "eric's") |
Eric V. Smith | 235a6f0 | 2015-09-19 14:51:32 -0400 | [diff] [blame] | 741 | |
| 742 | # Test concatenation within an expression |
| 743 | self.assertEqual(f'{"x" """eric"s""" "y"}', 'xeric"sy') |
| 744 | self.assertEqual(f'{"x" """eric"s"""}', 'xeric"s') |
| 745 | self.assertEqual(f'{"""eric"s""" "y"}', 'eric"sy') |
| 746 | self.assertEqual(f'{"""x""" """eric"s""" "y"}', 'xeric"sy') |
| 747 | self.assertEqual(f'{"""x""" """eric"s""" """y"""}', 'xeric"sy') |
| 748 | self.assertEqual(f'{r"""x""" """eric"s""" """y"""}', 'xeric"sy') |
| 749 | |
| 750 | def test_multiple_vars(self): |
| 751 | x = 98 |
| 752 | y = 'abc' |
| 753 | self.assertEqual(f'{x}{y}', '98abc') |
| 754 | |
| 755 | self.assertEqual(f'X{x}{y}', 'X98abc') |
| 756 | self.assertEqual(f'{x}X{y}', '98Xabc') |
| 757 | self.assertEqual(f'{x}{y}X', '98abcX') |
| 758 | |
| 759 | self.assertEqual(f'X{x}Y{y}', 'X98Yabc') |
| 760 | self.assertEqual(f'X{x}{y}Y', 'X98abcY') |
| 761 | self.assertEqual(f'{x}X{y}Y', '98XabcY') |
| 762 | |
| 763 | self.assertEqual(f'X{x}Y{y}Z', 'X98YabcZ') |
| 764 | |
| 765 | def test_closure(self): |
| 766 | def outer(x): |
| 767 | def inner(): |
| 768 | return f'x:{x}' |
| 769 | return inner |
| 770 | |
| 771 | self.assertEqual(outer('987')(), 'x:987') |
| 772 | self.assertEqual(outer(7)(), 'x:7') |
| 773 | |
| 774 | def test_arguments(self): |
| 775 | y = 2 |
| 776 | def f(x, width): |
| 777 | return f'x={x*y:{width}}' |
| 778 | |
| 779 | self.assertEqual(f('foo', 10), 'x=foofoo ') |
| 780 | x = 'bar' |
| 781 | self.assertEqual(f(10, 10), 'x= 20') |
| 782 | |
| 783 | def test_locals(self): |
| 784 | value = 123 |
| 785 | self.assertEqual(f'v:{value}', 'v:123') |
| 786 | |
| 787 | def test_missing_variable(self): |
| 788 | with self.assertRaises(NameError): |
| 789 | f'v:{value}' |
| 790 | |
| 791 | def test_missing_format_spec(self): |
| 792 | class O: |
| 793 | def __format__(self, spec): |
| 794 | if not spec: |
| 795 | return '*' |
| 796 | return spec |
| 797 | |
| 798 | self.assertEqual(f'{O():x}', 'x') |
| 799 | self.assertEqual(f'{O()}', '*') |
| 800 | self.assertEqual(f'{O():}', '*') |
| 801 | |
| 802 | self.assertEqual(f'{3:}', '3') |
| 803 | self.assertEqual(f'{3!s:}', '3') |
| 804 | |
| 805 | def test_global(self): |
| 806 | self.assertEqual(f'g:{a_global}', 'g:global variable') |
| 807 | self.assertEqual(f'g:{a_global!r}', "g:'global variable'") |
| 808 | |
| 809 | a_local = 'local variable' |
| 810 | self.assertEqual(f'g:{a_global} l:{a_local}', |
| 811 | 'g:global variable l:local variable') |
| 812 | self.assertEqual(f'g:{a_global!r}', |
| 813 | "g:'global variable'") |
| 814 | self.assertEqual(f'g:{a_global} l:{a_local!r}', |
| 815 | "g:global variable l:'local variable'") |
| 816 | |
| 817 | self.assertIn("module 'unittest' from", f'{unittest}') |
| 818 | |
| 819 | def test_shadowed_global(self): |
| 820 | a_global = 'really a local' |
| 821 | self.assertEqual(f'g:{a_global}', 'g:really a local') |
| 822 | self.assertEqual(f'g:{a_global!r}', "g:'really a local'") |
| 823 | |
| 824 | a_local = 'local variable' |
| 825 | self.assertEqual(f'g:{a_global} l:{a_local}', |
| 826 | 'g:really a local l:local variable') |
| 827 | self.assertEqual(f'g:{a_global!r}', |
| 828 | "g:'really a local'") |
| 829 | self.assertEqual(f'g:{a_global} l:{a_local!r}', |
| 830 | "g:really a local l:'local variable'") |
| 831 | |
| 832 | def test_call(self): |
| 833 | def foo(x): |
| 834 | return 'x=' + str(x) |
| 835 | |
| 836 | self.assertEqual(f'{foo(10)}', 'x=10') |
| 837 | |
| 838 | def test_nested_fstrings(self): |
| 839 | y = 5 |
| 840 | self.assertEqual(f'{f"{0}"*3}', '000') |
| 841 | self.assertEqual(f'{f"{y}"*3}', '555') |
Eric V. Smith | 235a6f0 | 2015-09-19 14:51:32 -0400 | [diff] [blame] | 842 | |
| 843 | def test_invalid_string_prefixes(self): |
| 844 | self.assertAllRaise(SyntaxError, 'unexpected EOF while parsing', |
| 845 | ["fu''", |
| 846 | "uf''", |
| 847 | "Fu''", |
| 848 | "fU''", |
| 849 | "Uf''", |
| 850 | "uF''", |
| 851 | "ufr''", |
| 852 | "urf''", |
| 853 | "fur''", |
| 854 | "fru''", |
| 855 | "rfu''", |
| 856 | "ruf''", |
| 857 | "FUR''", |
| 858 | "Fur''", |
Eric V. Smith | 451d0e3 | 2016-09-09 21:56:20 -0400 | [diff] [blame] | 859 | "fb''", |
| 860 | "fB''", |
| 861 | "Fb''", |
| 862 | "FB''", |
| 863 | "bf''", |
| 864 | "bF''", |
| 865 | "Bf''", |
| 866 | "BF''", |
Eric V. Smith | 235a6f0 | 2015-09-19 14:51:32 -0400 | [diff] [blame] | 867 | ]) |
| 868 | |
| 869 | def test_leading_trailing_spaces(self): |
| 870 | self.assertEqual(f'{ 3}', '3') |
| 871 | self.assertEqual(f'{ 3}', '3') |
Eric V. Smith | 235a6f0 | 2015-09-19 14:51:32 -0400 | [diff] [blame] | 872 | self.assertEqual(f'{3 }', '3') |
| 873 | self.assertEqual(f'{3 }', '3') |
Eric V. Smith | 235a6f0 | 2015-09-19 14:51:32 -0400 | [diff] [blame] | 874 | |
| 875 | self.assertEqual(f'expr={ {x: y for x, y in [(1, 2), ]}}', |
| 876 | 'expr={1: 2}') |
| 877 | self.assertEqual(f'expr={ {x: y for x, y in [(1, 2), ]} }', |
| 878 | 'expr={1: 2}') |
| 879 | |
Eric V. Smith | 235a6f0 | 2015-09-19 14:51:32 -0400 | [diff] [blame] | 880 | def test_not_equal(self): |
| 881 | # There's a special test for this because there's a special |
| 882 | # case in the f-string parser to look for != as not ending an |
| 883 | # expression. Normally it would, while looking for !s or !r. |
| 884 | |
| 885 | self.assertEqual(f'{3!=4}', 'True') |
| 886 | self.assertEqual(f'{3!=4:}', 'True') |
| 887 | self.assertEqual(f'{3!=4!s}', 'True') |
| 888 | self.assertEqual(f'{3!=4!s:.3}', 'Tru') |
| 889 | |
Eric V. Smith | 9a4135e | 2019-05-08 16:28:48 -0400 | [diff] [blame] | 890 | def test_equal_equal(self): |
| 891 | # Because an expression ending in = has special meaning, |
| 892 | # there's a special test for ==. Make sure it works. |
| 893 | |
| 894 | self.assertEqual(f'{0==1}', 'False') |
| 895 | |
Eric V. Smith | 235a6f0 | 2015-09-19 14:51:32 -0400 | [diff] [blame] | 896 | def test_conversions(self): |
| 897 | self.assertEqual(f'{3.14:10.10}', ' 3.14') |
| 898 | self.assertEqual(f'{3.14!s:10.10}', '3.14 ') |
| 899 | self.assertEqual(f'{3.14!r:10.10}', '3.14 ') |
| 900 | self.assertEqual(f'{3.14!a:10.10}', '3.14 ') |
| 901 | |
| 902 | self.assertEqual(f'{"a"}', 'a') |
| 903 | self.assertEqual(f'{"a"!r}', "'a'") |
| 904 | self.assertEqual(f'{"a"!a}', "'a'") |
| 905 | |
| 906 | # Not a conversion. |
| 907 | self.assertEqual(f'{"a!r"}', "a!r") |
| 908 | |
| 909 | # Not a conversion, but show that ! is allowed in a format spec. |
| 910 | self.assertEqual(f'{3.14:!<10.10}', '3.14!!!!!!') |
| 911 | |
Eric V. Smith | 235a6f0 | 2015-09-19 14:51:32 -0400 | [diff] [blame] | 912 | self.assertAllRaise(SyntaxError, 'f-string: invalid conversion character', |
| 913 | ["f'{3!g}'", |
| 914 | "f'{3!A}'", |
Eric V. Smith | 451d0e3 | 2016-09-09 21:56:20 -0400 | [diff] [blame] | 915 | "f'{3!3}'", |
| 916 | "f'{3!G}'", |
Eric V. Smith | 235a6f0 | 2015-09-19 14:51:32 -0400 | [diff] [blame] | 917 | "f'{3!!}'", |
| 918 | "f'{3!:}'", |
Eric V. Smith | 235a6f0 | 2015-09-19 14:51:32 -0400 | [diff] [blame] | 919 | "f'{3! s}'", # no space before conversion char |
Eric V. Smith | 235a6f0 | 2015-09-19 14:51:32 -0400 | [diff] [blame] | 920 | ]) |
| 921 | |
| 922 | self.assertAllRaise(SyntaxError, "f-string: expecting '}'", |
| 923 | ["f'{x!s{y}}'", |
| 924 | "f'{3!ss}'", |
| 925 | "f'{3!ss:}'", |
| 926 | "f'{3!ss:s}'", |
| 927 | ]) |
| 928 | |
| 929 | def test_assignment(self): |
| 930 | self.assertAllRaise(SyntaxError, 'invalid syntax', |
| 931 | ["f'' = 3", |
| 932 | "f'{0}' = x", |
| 933 | "f'{x}' = x", |
| 934 | ]) |
| 935 | |
| 936 | def test_del(self): |
| 937 | self.assertAllRaise(SyntaxError, 'invalid syntax', |
| 938 | ["del f''", |
| 939 | "del '' f''", |
| 940 | ]) |
| 941 | |
| 942 | def test_mismatched_braces(self): |
| 943 | self.assertAllRaise(SyntaxError, "f-string: single '}' is not allowed", |
| 944 | ["f'{{}'", |
| 945 | "f'{{}}}'", |
| 946 | "f'}'", |
| 947 | "f'x}'", |
| 948 | "f'x}x'", |
Jason R. Coombs | da25abf7 | 2016-11-06 11:14:48 -0500 | [diff] [blame] | 949 | r"f'\u007b}'", |
Eric V. Smith | 235a6f0 | 2015-09-19 14:51:32 -0400 | [diff] [blame] | 950 | |
| 951 | # Can't have { or } in a format spec. |
| 952 | "f'{3:}>10}'", |
Eric V. Smith | 235a6f0 | 2015-09-19 14:51:32 -0400 | [diff] [blame] | 953 | "f'{3:}}>10}'", |
| 954 | ]) |
| 955 | |
| 956 | self.assertAllRaise(SyntaxError, "f-string: expecting '}'", |
| 957 | ["f'{3:{{>10}'", |
| 958 | "f'{3'", |
| 959 | "f'{3!'", |
| 960 | "f'{3:'", |
| 961 | "f'{3!s'", |
| 962 | "f'{3!s:'", |
| 963 | "f'{3!s:3'", |
| 964 | "f'x{'", |
| 965 | "f'x{x'", |
Eric V. Smith | 451d0e3 | 2016-09-09 21:56:20 -0400 | [diff] [blame] | 966 | "f'{x'", |
Eric V. Smith | 235a6f0 | 2015-09-19 14:51:32 -0400 | [diff] [blame] | 967 | "f'{3:s'", |
| 968 | "f'{{{'", |
| 969 | "f'{{}}{'", |
| 970 | "f'{'", |
| 971 | ]) |
| 972 | |
Eric V. Smith | 235a6f0 | 2015-09-19 14:51:32 -0400 | [diff] [blame] | 973 | # But these are just normal strings. |
| 974 | self.assertEqual(f'{"{"}', '{') |
| 975 | self.assertEqual(f'{"}"}', '}') |
| 976 | self.assertEqual(f'{3:{"}"}>10}', '}}}}}}}}}3') |
| 977 | self.assertEqual(f'{2:{"{"}>10}', '{{{{{{{{{2') |
| 978 | |
| 979 | def test_if_conditional(self): |
| 980 | # There's special logic in compile.c to test if the |
| 981 | # conditional for an if (and while) are constants. Exercise |
| 982 | # that code. |
| 983 | |
| 984 | def test_fstring(x, expected): |
| 985 | flag = 0 |
| 986 | if f'{x}': |
| 987 | flag = 1 |
| 988 | else: |
| 989 | flag = 2 |
| 990 | self.assertEqual(flag, expected) |
| 991 | |
| 992 | def test_concat_empty(x, expected): |
| 993 | flag = 0 |
| 994 | if '' f'{x}': |
| 995 | flag = 1 |
| 996 | else: |
| 997 | flag = 2 |
| 998 | self.assertEqual(flag, expected) |
| 999 | |
| 1000 | def test_concat_non_empty(x, expected): |
| 1001 | flag = 0 |
| 1002 | if ' ' f'{x}': |
| 1003 | flag = 1 |
| 1004 | else: |
| 1005 | flag = 2 |
| 1006 | self.assertEqual(flag, expected) |
| 1007 | |
| 1008 | test_fstring('', 2) |
| 1009 | test_fstring(' ', 1) |
| 1010 | |
| 1011 | test_concat_empty('', 2) |
| 1012 | test_concat_empty(' ', 1) |
| 1013 | |
| 1014 | test_concat_non_empty('', 1) |
| 1015 | test_concat_non_empty(' ', 1) |
| 1016 | |
| 1017 | def test_empty_format_specifier(self): |
| 1018 | x = 'test' |
| 1019 | self.assertEqual(f'{x}', 'test') |
| 1020 | self.assertEqual(f'{x:}', 'test') |
| 1021 | self.assertEqual(f'{x!s:}', 'test') |
| 1022 | self.assertEqual(f'{x!r:}', "'test'") |
| 1023 | |
| 1024 | def test_str_format_differences(self): |
| 1025 | d = {'a': 'string', |
| 1026 | 0: 'integer', |
| 1027 | } |
| 1028 | a = 0 |
| 1029 | self.assertEqual(f'{d[0]}', 'integer') |
| 1030 | self.assertEqual(f'{d["a"]}', 'string') |
| 1031 | self.assertEqual(f'{d[a]}', 'integer') |
| 1032 | self.assertEqual('{d[a]}'.format(d=d), 'string') |
| 1033 | self.assertEqual('{d[0]}'.format(d=d), 'integer') |
| 1034 | |
Eric V. Smith | 135d5f4 | 2016-02-05 18:23:08 -0500 | [diff] [blame] | 1035 | def test_errors(self): |
| 1036 | # see issue 26287 |
Serhiy Storchaka | 13c8f32 | 2016-10-31 08:13:00 +0200 | [diff] [blame] | 1037 | self.assertAllRaise(TypeError, 'unsupported', |
Eric V. Smith | 135d5f4 | 2016-02-05 18:23:08 -0500 | [diff] [blame] | 1038 | [r"f'{(lambda: 0):x}'", |
| 1039 | r"f'{(0,):x}'", |
| 1040 | ]) |
| 1041 | self.assertAllRaise(ValueError, 'Unknown format code', |
| 1042 | [r"f'{1000:j}'", |
| 1043 | r"f'{1000:j}'", |
| 1044 | ]) |
| 1045 | |
Eric V. Smith | 235a6f0 | 2015-09-19 14:51:32 -0400 | [diff] [blame] | 1046 | def test_loop(self): |
| 1047 | for i in range(1000): |
| 1048 | self.assertEqual(f'i:{i}', 'i:' + str(i)) |
| 1049 | |
| 1050 | def test_dict(self): |
| 1051 | d = {'"': 'dquote', |
| 1052 | "'": 'squote', |
| 1053 | 'foo': 'bar', |
| 1054 | } |
Eric V. Smith | 235a6f0 | 2015-09-19 14:51:32 -0400 | [diff] [blame] | 1055 | self.assertEqual(f'''{d["'"]}''', 'squote') |
| 1056 | self.assertEqual(f"""{d['"']}""", 'dquote') |
| 1057 | |
| 1058 | self.assertEqual(f'{d["foo"]}', 'bar') |
| 1059 | self.assertEqual(f"{d['foo']}", 'bar') |
Eric V. Smith | 235a6f0 | 2015-09-19 14:51:32 -0400 | [diff] [blame] | 1060 | |
ericvsmith | 11e97f2 | 2017-06-16 06:19:32 -0400 | [diff] [blame] | 1061 | def test_backslash_char(self): |
| 1062 | # Check eval of a backslash followed by a control char. |
| 1063 | # See bpo-30682: this used to raise an assert in pydebug mode. |
| 1064 | self.assertEqual(eval('f"\\\n"'), '') |
| 1065 | self.assertEqual(eval('f"\\\r"'), '') |
| 1066 | |
Eric V. Smith | 9a4135e | 2019-05-08 16:28:48 -0400 | [diff] [blame] | 1067 | def test_debug_conversion(self): |
| 1068 | x = 'A string' |
| 1069 | self.assertEqual(f'{x=}', 'x=' + repr(x)) |
| 1070 | self.assertEqual(f'{x =}', 'x =' + repr(x)) |
| 1071 | self.assertEqual(f'{x=!s}', 'x=' + str(x)) |
| 1072 | self.assertEqual(f'{x=!r}', 'x=' + repr(x)) |
| 1073 | self.assertEqual(f'{x=!a}', 'x=' + ascii(x)) |
| 1074 | |
| 1075 | x = 2.71828 |
| 1076 | self.assertEqual(f'{x=:.2f}', 'x=' + format(x, '.2f')) |
| 1077 | self.assertEqual(f'{x=:}', 'x=' + format(x, '')) |
| 1078 | self.assertEqual(f'{x=!r:^20}', 'x=' + format(repr(x), '^20')) |
| 1079 | self.assertEqual(f'{x=!s:^20}', 'x=' + format(str(x), '^20')) |
| 1080 | self.assertEqual(f'{x=!a:^20}', 'x=' + format(ascii(x), '^20')) |
| 1081 | |
| 1082 | x = 9 |
| 1083 | self.assertEqual(f'{3*x+15=}', '3*x+15=42') |
| 1084 | |
| 1085 | # There is code in ast.c that deals with non-ascii expression values. So, |
| 1086 | # use a unicode identifier to trigger that. |
| 1087 | tenπ = 31.4 |
| 1088 | self.assertEqual(f'{tenπ=:.2f}', 'tenπ=31.40') |
| 1089 | |
| 1090 | # Also test with Unicode in non-identifiers. |
| 1091 | self.assertEqual(f'{"Σ"=}', '"Σ"=\'Σ\'') |
| 1092 | |
| 1093 | # Make sure nested fstrings still work. |
| 1094 | self.assertEqual(f'{f"{3.1415=:.1f}":*^20}', '*****3.1415=3.1*****') |
| 1095 | |
| 1096 | # Make sure text before and after an expression with = works |
| 1097 | # correctly. |
| 1098 | pi = 'π' |
| 1099 | self.assertEqual(f'alpha α {pi=} ω omega', "alpha α pi='π' ω omega") |
| 1100 | |
| 1101 | # Check multi-line expressions. |
| 1102 | self.assertEqual(f'''{ |
| 1103 | 3 |
| 1104 | =}''', '\n3\n=3') |
| 1105 | |
| 1106 | # Since = is handled specially, make sure all existing uses of |
| 1107 | # it still work. |
| 1108 | |
| 1109 | self.assertEqual(f'{0==1}', 'False') |
| 1110 | self.assertEqual(f'{0!=1}', 'True') |
| 1111 | self.assertEqual(f'{0<=1}', 'True') |
| 1112 | self.assertEqual(f'{0>=1}', 'False') |
| 1113 | self.assertEqual(f'{(x:="5")}', '5') |
| 1114 | self.assertEqual(x, '5') |
| 1115 | self.assertEqual(f'{(x:=5)}', '5') |
| 1116 | self.assertEqual(x, 5) |
| 1117 | self.assertEqual(f'{"="}', '=') |
| 1118 | |
| 1119 | x = 20 |
| 1120 | # This isn't an assignment expression, it's 'x', with a format |
| 1121 | # spec of '=10'. See test_walrus: you need to use parens. |
| 1122 | self.assertEqual(f'{x:=10}', ' 20') |
| 1123 | |
| 1124 | # Test named function parameters, to make sure '=' parsing works |
| 1125 | # there. |
| 1126 | def f(a): |
| 1127 | nonlocal x |
| 1128 | oldx = x |
| 1129 | x = a |
| 1130 | return oldx |
| 1131 | x = 0 |
| 1132 | self.assertEqual(f'{f(a="3=")}', '0') |
| 1133 | self.assertEqual(x, '3=') |
| 1134 | self.assertEqual(f'{f(a=4)}', '3=') |
| 1135 | self.assertEqual(x, 4) |
| 1136 | |
| 1137 | # Make sure __format__ is being called. |
| 1138 | class C: |
| 1139 | def __format__(self, s): |
| 1140 | return f'FORMAT-{s}' |
| 1141 | def __repr__(self): |
| 1142 | return 'REPR' |
| 1143 | |
| 1144 | self.assertEqual(f'{C()=}', 'C()=REPR') |
| 1145 | self.assertEqual(f'{C()=!r}', 'C()=REPR') |
| 1146 | self.assertEqual(f'{C()=:}', 'C()=FORMAT-') |
| 1147 | self.assertEqual(f'{C()=: }', 'C()=FORMAT- ') |
| 1148 | self.assertEqual(f'{C()=:x}', 'C()=FORMAT-x') |
| 1149 | self.assertEqual(f'{C()=!r:*^20}', 'C()=********REPR********') |
| 1150 | |
Pablo Galindo | 26f55c2 | 2019-05-12 01:43:04 +0100 | [diff] [blame] | 1151 | self.assertRaises(SyntaxError, eval, "f'{C=]'") |
| 1152 | |
Eric V. Smith | 6f6ff8a | 2019-05-27 15:31:52 -0400 | [diff] [blame] | 1153 | # Make sure leading and following text works. |
| 1154 | x = 'foo' |
| 1155 | self.assertEqual(f'X{x=}Y', 'Xx='+repr(x)+'Y') |
| 1156 | |
| 1157 | # Make sure whitespace around the = works. |
| 1158 | self.assertEqual(f'X{x =}Y', 'Xx ='+repr(x)+'Y') |
| 1159 | self.assertEqual(f'X{x= }Y', 'Xx= '+repr(x)+'Y') |
| 1160 | self.assertEqual(f'X{x = }Y', 'Xx = '+repr(x)+'Y') |
| 1161 | |
| 1162 | # These next lines contains tabs. Backslash escapes don't |
| 1163 | # work in f-strings. |
Kyle Stanley | 24b5b36 | 2019-07-21 22:48:45 -0400 | [diff] [blame] | 1164 | # patchcheck doesn't like these tabs. So the only way to test |
Eric V. Smith | 6f6ff8a | 2019-05-27 15:31:52 -0400 | [diff] [blame] | 1165 | # this will be to dynamically created and exec the f-strings. But |
| 1166 | # that's such a hassle I'll save it for another day. For now, convert |
| 1167 | # the tabs to spaces just to shut up patchcheck. |
| 1168 | #self.assertEqual(f'X{x =}Y', 'Xx\t='+repr(x)+'Y') |
| 1169 | #self.assertEqual(f'X{x = }Y', 'Xx\t=\t'+repr(x)+'Y') |
| 1170 | |
Eric V. Smith | 9a4135e | 2019-05-08 16:28:48 -0400 | [diff] [blame] | 1171 | def test_walrus(self): |
| 1172 | x = 20 |
| 1173 | # This isn't an assignment expression, it's 'x', with a format |
| 1174 | # spec of '=10'. |
| 1175 | self.assertEqual(f'{x:=10}', ' 20') |
| 1176 | |
| 1177 | # This is an assignment expression, which requires parens. |
| 1178 | self.assertEqual(f'{(x:=10)}', '10') |
| 1179 | self.assertEqual(x, 10) |
| 1180 | |
Łukasz Langa | e7c566c | 2017-09-06 17:27:58 -0700 | [diff] [blame] | 1181 | |
Eric V. Smith | 235a6f0 | 2015-09-19 14:51:32 -0400 | [diff] [blame] | 1182 | if __name__ == '__main__': |
| 1183 | unittest.main() |