SCons/Tool/MSCommon/MSVC/Dispatcher.py

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  23
  24 """
  25 Internal method dispatcher for Microsoft Visual C/C++.
  26
  27 MSVC modules can register their module (register_modulename) and individual
  28 classes (register_class) with the method dispatcher during initialization. MSVC
  29 modules tend to be registered immediately after the Dispatcher import near the
  30 top of the file. Methods in the MSVC modules can be invoked indirectly without
  31 having to hard-code the method calls effectively decoupling the upstream module
  32 with the downstream modules:
  33
  34 The reset method dispatches calls to all registered objects with a reset method
  35 and/or a _reset method. The reset methods are used to restore data structures
  36 to their initial state for testing purposes. Typically, this involves clearing
  37 cached values.
  38
  39 The verify method dispatches calls to all registered objects with a verify
  40 method and/or a _verify method. The verify methods are used to check that
  41 initialized data structures distributed across multiple modules are internally
  42 consistent.  An exception is raised when a verification constraint violation
  43 is detected.  Typically, this verifies that initialized dictionaries support
  44 all of the requisite keys as new versions are added.
  45 """
  46
  47 import sys
  48
  49 from ..common import (
  50     debug,
  51 )
  52
  53 _refs = []
  54
  55
  56 def register_modulename(modname) -> None:
  57     module = sys.modules[modname]
  58     _refs.append(module)
  59
  60
  61 def register_class(ref) -> None:
  62     _refs.append(ref)
  63
  64
  65 def reset() -> None:
  66     debug('')
  67     for ref in _refs:
  68         for method in ['reset', '_reset']:
  69             if not hasattr(ref, method) or not callable(getattr(ref, method, None)):
  70                 continue
  71             debug('call %s.%s()', ref.__name__, method)
  72             func = getattr(ref, method)
  73             func()
  74
  75
  76 def verify() -> None:
  77     debug('')
  78     for ref in _refs:
  79         for method in ['verify', '_verify']:
  80             if not hasattr(ref, method) or not callable(getattr(ref, method, None)):
  81                 continue
  82             debug('call %s.%s()', ref.__name__, method)
  83             func = getattr(ref, method)
  84             func()