| 1 | """
 | 
| 2 | util.py
 | 
| 3 | """
 | 
| 4 | from __future__ import print_function
 | 
| 5 | 
 | 
| 6 | import sys
 | 
| 7 | from mypy.nodes import CallExpr, IfStmt, Block, Expression, MypyFile
 | 
| 8 | 
 | 
| 9 | from typing import Any, Sequence, Optional
 | 
| 10 | 
 | 
| 11 | # Used by cppgen_pass and const_pass
 | 
| 12 | 
 | 
| 13 | # mycpp/examples/small_str.py sorta works with this!
 | 
| 14 | #SMALL_STR = True
 | 
| 15 | 
 | 
| 16 | SMALL_STR = False
 | 
| 17 | 
 | 
| 18 | SymbolPath = Sequence[str]
 | 
| 19 | 
 | 
| 20 | 
 | 
| 21 | def log(msg: str, *args: Any) -> None:
 | 
| 22 |     if args:
 | 
| 23 |         msg = msg % args
 | 
| 24 |     print(msg, file=sys.stderr)
 | 
| 25 | 
 | 
| 26 | 
 | 
| 27 | def join_name(parts: SymbolPath,
 | 
| 28 |               strip_package: bool = False,
 | 
| 29 |               delim: str = '::') -> str:
 | 
| 30 |     """
 | 
| 31 |     Join the given name path into a string with the given delimiter.
 | 
| 32 |     Use strip_package to remove the top-level directory (e.g. `core`, `ysh`)
 | 
| 33 |     when dealing with C++ namespaces.
 | 
| 34 |     """
 | 
| 35 |     if not strip_package:
 | 
| 36 |         return delim.join(parts)
 | 
| 37 | 
 | 
| 38 |     if len(parts) > 1:
 | 
| 39 |         return delim.join(('', ) + parts[1:])
 | 
| 40 | 
 | 
| 41 |     return parts[0]
 | 
| 42 | 
 | 
| 43 | 
 | 
| 44 | def split_py_name(name: str) -> SymbolPath:
 | 
| 45 |     ret = tuple(name.split('.'))
 | 
| 46 |     if len(ret) and ret[0] == 'mycpp':
 | 
| 47 |         # Drop the prefix 'mycpp.' if present. This makes names compatible with
 | 
| 48 |         # the examples that use testpkg.
 | 
| 49 |         return ret[1:]
 | 
| 50 | 
 | 
| 51 |     return ret
 | 
| 52 | 
 | 
| 53 | 
 | 
| 54 | def _collect_cases(module_path: str,
 | 
| 55 |                    if_node: IfStmt,
 | 
| 56 |                    out: list[tuple[Expression, Block]],
 | 
| 57 |                    errors=None) -> Optional[Block] | bool:
 | 
| 58 |     """
 | 
| 59 |     The MyPy AST has a recursive structure for if-elif-elif rather than a
 | 
| 60 |     flat one.  It's a bit confusing.
 | 
| 61 | 
 | 
| 62 |     Appends (expr, block) cases to out param, and returns the default
 | 
| 63 |     block, which has no expression.
 | 
| 64 | 
 | 
| 65 |     default block may be None.
 | 
| 66 | 
 | 
| 67 |     Returns False if there is no default block.
 | 
| 68 |     """
 | 
| 69 |     assert isinstance(if_node, IfStmt), if_node
 | 
| 70 |     assert len(if_node.expr) == 1, if_node.expr
 | 
| 71 |     assert len(if_node.body) == 1, if_node.body
 | 
| 72 | 
 | 
| 73 |     expr = if_node.expr[0]
 | 
| 74 |     body = if_node.body[0]
 | 
| 75 | 
 | 
| 76 |     if not isinstance(expr, CallExpr):
 | 
| 77 |         if errors is not None:
 | 
| 78 |             errors.append((module_path, expr.line,
 | 
| 79 |                            'Expected call like case(x), got %s' % expr))
 | 
| 80 |         return
 | 
| 81 | 
 | 
| 82 |     out.append((expr, body))
 | 
| 83 | 
 | 
| 84 |     if if_node.else_body:
 | 
| 85 |         first_of_block = if_node.else_body.body[0]
 | 
| 86 |         # BUG: this is meant for 'elif' only.  But it also triggers for
 | 
| 87 |         #
 | 
| 88 |         # else:
 | 
| 89 |         #   if 0:
 | 
| 90 | 
 | 
| 91 |         if isinstance(first_of_block, IfStmt):
 | 
| 92 |             return _collect_cases(module_path, first_of_block, out, errors)
 | 
| 93 |         else:
 | 
| 94 |             # default case - no expression
 | 
| 95 |             return if_node.else_body
 | 
| 96 | 
 | 
| 97 |     return False  # NO DEFAULT BLOCK - Different than None
 | 
| 98 | 
 | 
| 99 | 
 | 
| 100 | def ShouldSkipPyFile(node: MypyFile) -> bool:
 | 
| 101 |     # Skip some stdlib stuff.  A lot of it is brought in by 'import
 | 
| 102 |     # typing'. These module are special; their contents are currently all
 | 
| 103 |     # built-in primitives.
 | 
| 104 |     return node.fullname in ('__future__', 'sys', 'types', 'typing', 'abc',
 | 
| 105 |                              '_ast', 'ast', '_weakrefset', 'collections',
 | 
| 106 |                              'cStringIO', 're', 'builtins')
 |