djavu-asus/elpy/rpc-venv/lib/python3.11/site-packages/black/handle_ipynb_magics.py

   1 """Functions to process IPython magics with."""
   2
   3 import ast
   4 import collections
   5 import dataclasses
   6 import secrets
   7 import sys
   8 from functools import lru_cache
   9 from importlib.util import find_spec
  10 from typing import Dict, List, Optional, Tuple
  11
  12 if sys.version_info >= (3, 10):
  13     from typing import TypeGuard
  14 else:
  15     from typing_extensions import TypeGuard
  16
  17 from black.output import out
  18 from black.report import NothingChanged
  19
  20 TRANSFORMED_MAGICS = frozenset(
  21     (
  22         "get_ipython().run_cell_magic",
  23         "get_ipython().system",
  24         "get_ipython().getoutput",
  25         "get_ipython().run_line_magic",
  26     )
  27 )
  28 TOKENS_TO_IGNORE = frozenset(
  29     (
  30         "ENDMARKER",
  31         "NL",
  32         "NEWLINE",
  33         "COMMENT",
  34         "DEDENT",
  35         "UNIMPORTANT_WS",
  36         "ESCAPED_NL",
  37     )
  38 )
  39 PYTHON_CELL_MAGICS = frozenset(
  40     (
  41         "capture",
  42         "prun",
  43         "pypy",
  44         "python",
  45         "python3",
  46         "time",
  47         "timeit",
  48     )
  49 )
  50 TOKEN_HEX = secrets.token_hex
  51
  52
  53 @dataclasses.dataclass(frozen=True)
  54 class Replacement:
  55     mask: str
  56     src: str
  57
  58
  59 @lru_cache
  60 def jupyter_dependencies_are_installed(*, warn: bool) -> bool:
  61     installed = (
  62         find_spec("tokenize_rt") is not None and find_spec("IPython") is not None
  63     )
  64     if not installed and warn:
  65         msg = (
  66             "Skipping .ipynb files as Jupyter dependencies are not installed.\n"
  67             'You can fix this by running ``pip install "black[jupyter]"``'
  68         )
  69         out(msg)
  70     return installed
  71
  72
  73 def remove_trailing_semicolon(src: str) -> Tuple[str, bool]:
  74     """Remove trailing semicolon from Jupyter notebook cell.
  75
  76     For example,
  77
  78         fig, ax = plt.subplots()
  79         ax.plot(x_data, y_data);  # plot data
  80
  81     would become
  82
  83         fig, ax = plt.subplots()
  84         ax.plot(x_data, y_data)  # plot data
  85
  86     Mirrors the logic in `quiet` from `IPython.core.displayhook`, but uses
  87     ``tokenize_rt`` so that round-tripping works fine.
  88     """
  89     from tokenize_rt import reversed_enumerate, src_to_tokens, tokens_to_src
  90
  91     tokens = src_to_tokens(src)
  92     trailing_semicolon = False
  93     for idx, token in reversed_enumerate(tokens):
  94         if token.name in TOKENS_TO_IGNORE:
  95             continue
  96         if token.name == "OP" and token.src == ";":
  97             del tokens[idx]
  98             trailing_semicolon = True
  99         break
 100     if not trailing_semicolon:
 101         return src, False
 102     return tokens_to_src(tokens), True
 103
 104
 105 def put_trailing_semicolon_back(src: str, has_trailing_semicolon: bool) -> str:
 106     """Put trailing semicolon back if cell originally had it.
 107
 108     Mirrors the logic in `quiet` from `IPython.core.displayhook`, but uses
 109     ``tokenize_rt`` so that round-tripping works fine.
 110     """
 111     if not has_trailing_semicolon:
 112         return src
 113     from tokenize_rt import reversed_enumerate, src_to_tokens, tokens_to_src
 114
 115     tokens = src_to_tokens(src)
 116     for idx, token in reversed_enumerate(tokens):
 117         if token.name in TOKENS_TO_IGNORE:
 118             continue
 119         tokens[idx] = token._replace(src=token.src + ";")
 120         break
 121     else:  # pragma: nocover
 122         raise AssertionError(
 123             "INTERNAL ERROR: Was not able to reinstate trailing semicolon. "
 124             "Please report a bug on https://github.com/psf/black/issues.  "
 125         ) from None
 126     return str(tokens_to_src(tokens))
 127
 128
 129 def mask_cell(src: str) -> Tuple[str, List[Replacement]]:
 130     """Mask IPython magics so content becomes parseable Python code.
 131
 132     For example,
 133
 134         %matplotlib inline
 135         'foo'
 136
 137     becomes
 138
 139         "25716f358c32750e"
 140         'foo'
 141
 142     The replacements are returned, along with the transformed code.
 143     """
 144     replacements: List[Replacement] = []
 145     try:
 146         ast.parse(src)
 147     except SyntaxError:
 148         # Might have IPython magics, will process below.
 149         pass
 150     else:
 151         # Syntax is fine, nothing to mask, early return.
 152         return src, replacements
 153
 154     from IPython.core.inputtransformer2 import TransformerManager
 155
 156     transformer_manager = TransformerManager()
 157     transformed = transformer_manager.transform_cell(src)
 158     transformed, cell_magic_replacements = replace_cell_magics(transformed)
 159     replacements += cell_magic_replacements
 160     transformed = transformer_manager.transform_cell(transformed)
 161     transformed, magic_replacements = replace_magics(transformed)
 162     if len(transformed.splitlines()) != len(src.splitlines()):
 163         # Multi-line magic, not supported.
 164         raise NothingChanged
 165     replacements += magic_replacements
 166     return transformed, replacements
 167
 168
 169 def get_token(src: str, magic: str) -> str:
 170     """Return randomly generated token to mask IPython magic with.
 171
 172     For example, if 'magic' was `%matplotlib inline`, then a possible
 173     token to mask it with would be `"43fdd17f7e5ddc83"`. The token
 174     will be the same length as the magic, and we make sure that it was
 175     not already present anywhere else in the cell.
 176     """
 177     assert magic
 178     nbytes = max(len(magic) // 2 - 1, 1)
 179     token = TOKEN_HEX(nbytes)
 180     counter = 0
 181     while token in src:
 182         token = TOKEN_HEX(nbytes)
 183         counter += 1
 184         if counter > 100:
 185             raise AssertionError(
 186                 "INTERNAL ERROR: Black was not able to replace IPython magic. "
 187                 "Please report a bug on https://github.com/psf/black/issues.  "
 188                 f"The magic might be helpful: {magic}"
 189             ) from None
 190     if len(token) + 2 < len(magic):
 191         token = f"{token}."
 192     return f'"{token}"'
 193
 194
 195 def replace_cell_magics(src: str) -> Tuple[str, List[Replacement]]:
 196     """Replace cell magic with token.
 197
 198     Note that 'src' will already have been processed by IPython's
 199     TransformerManager().transform_cell.
 200
 201     Example,
 202
 203         get_ipython().run_cell_magic('t', '-n1', 'ls =!ls\\n')
 204
 205     becomes
 206
 207         "a794."
 208         ls =!ls
 209
 210     The replacement, along with the transformed code, is returned.
 211     """
 212     replacements: List[Replacement] = []
 213
 214     tree = ast.parse(src)
 215
 216     cell_magic_finder = CellMagicFinder()
 217     cell_magic_finder.visit(tree)
 218     if cell_magic_finder.cell_magic is None:
 219         return src, replacements
 220     header = cell_magic_finder.cell_magic.header
 221     mask = get_token(src, header)
 222     replacements.append(Replacement(mask=mask, src=header))
 223     return f"{mask}\n{cell_magic_finder.cell_magic.body}", replacements
 224
 225
 226 def replace_magics(src: str) -> Tuple[str, List[Replacement]]:
 227     """Replace magics within body of cell.
 228
 229     Note that 'src' will already have been processed by IPython's
 230     TransformerManager().transform_cell.
 231
 232     Example, this
 233
 234         get_ipython().run_line_magic('matplotlib', 'inline')
 235         'foo'
 236
 237     becomes
 238
 239         "5e67db56d490fd39"
 240         'foo'
 241
 242     The replacement, along with the transformed code, are returned.
 243     """
 244     replacements = []
 245     magic_finder = MagicFinder()
 246     magic_finder.visit(ast.parse(src))
 247     new_srcs = []
 248     for i, line in enumerate(src.splitlines(), start=1):
 249         if i in magic_finder.magics:
 250             offsets_and_magics = magic_finder.magics[i]
 251             if len(offsets_and_magics) != 1:  # pragma: nocover
 252                 raise AssertionError(
 253                     f"Expecting one magic per line, got: {offsets_and_magics}\n"
 254                     "Please report a bug on https://github.com/psf/black/issues."
 255                 )
 256             col_offset, magic = (
 257                 offsets_and_magics[0].col_offset,
 258                 offsets_and_magics[0].magic,
 259             )
 260             mask = get_token(src, magic)
 261             replacements.append(Replacement(mask=mask, src=magic))
 262             line = line[:col_offset] + mask
 263         new_srcs.append(line)
 264     return "\n".join(new_srcs), replacements
 265
 266
 267 def unmask_cell(src: str, replacements: List[Replacement]) -> str:
 268     """Remove replacements from cell.
 269
 270     For example
 271
 272         "9b20"
 273         foo = bar
 274
 275     becomes
 276
 277         %%time
 278         foo = bar
 279     """
 280     for replacement in replacements:
 281         src = src.replace(replacement.mask, replacement.src)
 282     return src
 283
 284
 285 def _is_ipython_magic(node: ast.expr) -> TypeGuard[ast.Attribute]:
 286     """Check if attribute is IPython magic.
 287
 288     Note that the source of the abstract syntax tree
 289     will already have been processed by IPython's
 290     TransformerManager().transform_cell.
 291     """
 292     return (
 293         isinstance(node, ast.Attribute)
 294         and isinstance(node.value, ast.Call)
 295         and isinstance(node.value.func, ast.Name)
 296         and node.value.func.id == "get_ipython"
 297     )
 298
 299
 300 def _get_str_args(args: List[ast.expr]) -> List[str]:
 301     str_args = []
 302     for arg in args:
 303         assert isinstance(arg, ast.Str)
 304         str_args.append(arg.s)
 305     return str_args
 306
 307
 308 @dataclasses.dataclass(frozen=True)
 309 class CellMagic:
 310     name: str
 311     params: Optional[str]
 312     body: str
 313
 314     @property
 315     def header(self) -> str:
 316         if self.params:
 317             return f"%%{self.name} {self.params}"
 318         return f"%%{self.name}"
 319
 320
 321 # ast.NodeVisitor + dataclass = breakage under mypyc.
 322 class CellMagicFinder(ast.NodeVisitor):
 323     """Find cell magics.
 324
 325     Note that the source of the abstract syntax tree
 326     will already have been processed by IPython's
 327     TransformerManager().transform_cell.
 328
 329     For example,
 330
 331         %%time\n
 332         foo()
 333
 334     would have been transformed to
 335
 336         get_ipython().run_cell_magic('time', '', 'foo()\\n')
 337
 338     and we look for instances of the latter.
 339     """
 340
 341     def __init__(self, cell_magic: Optional[CellMagic] = None) -> None:
 342         self.cell_magic = cell_magic
 343
 344     def visit_Expr(self, node: ast.Expr) -> None:
 345         """Find cell magic, extract header and body."""
 346         if (
 347             isinstance(node.value, ast.Call)
 348             and _is_ipython_magic(node.value.func)
 349             and node.value.func.attr == "run_cell_magic"
 350         ):
 351             args = _get_str_args(node.value.args)
 352             self.cell_magic = CellMagic(name=args[0], params=args[1], body=args[2])
 353         self.generic_visit(node)
 354
 355
 356 @dataclasses.dataclass(frozen=True)
 357 class OffsetAndMagic:
 358     col_offset: int
 359     magic: str
 360
 361
 362 # Unsurprisingly, subclassing ast.NodeVisitor means we can't use dataclasses here
 363 # as mypyc will generate broken code.
 364 class MagicFinder(ast.NodeVisitor):
 365     """Visit cell to look for get_ipython calls.
 366
 367     Note that the source of the abstract syntax tree
 368     will already have been processed by IPython's
 369     TransformerManager().transform_cell.
 370
 371     For example,
 372
 373         %matplotlib inline
 374
 375     would have been transformed to
 376
 377         get_ipython().run_line_magic('matplotlib', 'inline')
 378
 379     and we look for instances of the latter (and likewise for other
 380     types of magics).
 381     """
 382
 383     def __init__(self) -> None:
 384         self.magics: Dict[int, List[OffsetAndMagic]] = collections.defaultdict(list)
 385
 386     def visit_Assign(self, node: ast.Assign) -> None:
 387         """Look for system assign magics.
 388
 389         For example,
 390
 391             black_version = !black --version
 392             env = %env var
 393
 394         would have been (respectively) transformed to
 395
 396             black_version = get_ipython().getoutput('black --version')
 397             env = get_ipython().run_line_magic('env', 'var')
 398
 399         and we look for instances of any of the latter.
 400         """
 401         if isinstance(node.value, ast.Call) and _is_ipython_magic(node.value.func):
 402             args = _get_str_args(node.value.args)
 403             if node.value.func.attr == "getoutput":
 404                 src = f"!{args[0]}"
 405             elif node.value.func.attr == "run_line_magic":
 406                 src = f"%{args[0]}"
 407                 if args[1]:
 408                     src += f" {args[1]}"
 409             else:
 410                 raise AssertionError(
 411                     f"Unexpected IPython magic {node.value.func.attr!r} found. "
 412                     "Please report a bug on https://github.com/psf/black/issues."
 413                 ) from None
 414             self.magics[node.value.lineno].append(
 415                 OffsetAndMagic(node.value.col_offset, src)
 416             )
 417         self.generic_visit(node)
 418
 419     def visit_Expr(self, node: ast.Expr) -> None:
 420         """Look for magics in body of cell.
 421
 422         For examples,
 423
 424             !ls
 425             !!ls
 426             ?ls
 427             ??ls
 428
 429         would (respectively) get transformed to
 430
 431             get_ipython().system('ls')
 432             get_ipython().getoutput('ls')
 433             get_ipython().run_line_magic('pinfo', 'ls')
 434             get_ipython().run_line_magic('pinfo2', 'ls')
 435
 436         and we look for instances of any of the latter.
 437         """
 438         if isinstance(node.value, ast.Call) and _is_ipython_magic(node.value.func):
 439             args = _get_str_args(node.value.args)
 440             if node.value.func.attr == "run_line_magic":
 441                 if args[0] == "pinfo":
 442                     src = f"?{args[1]}"
 443                 elif args[0] == "pinfo2":
 444                     src = f"??{args[1]}"
 445                 else:
 446                     src = f"%{args[0]}"
 447                     if args[1]:
 448                         src += f" {args[1]}"
 449             elif node.value.func.attr == "system":
 450                 src = f"!{args[0]}"
 451             elif node.value.func.attr == "getoutput":
 452                 src = f"!!{args[0]}"
 453             else:
 454                 raise NothingChanged  # unsupported magic.
 455             self.magics[node.value.lineno].append(
 456                 OffsetAndMagic(node.value.col_offset, src)
 457             )
 458         self.generic_visit(node)