Rework __diag__ and __compat__ to be actual classes instead of just namespaces, to add helpful behavior and methods

1 files changed, 59 insertions, 16 deletions

diff --git a/pyparsing.py b/pyparsing.py
index aa49a06..43f1abc 100644
--- a/pyparsing.py
+++ b/pyparsing.py
@@ -96,7 +96,7 @@ classes inherit from. Use the docstrings for examples of how to:
 """
 
 __version__ = "2.5.0a1"
-__versionTime__ = "09 Aug 2019 11:27 UTC"
+__versionTime__ = "10 Aug 2019 11:56 UTC"
 __author__ = "Paul McGuire <ptmcg@users.sourceforge.net>"
 
 import string
@@ -127,24 +127,52 @@ from collections.abc import MutableMapping, Mapping
 from collections import OrderedDict
 from types import SimpleNamespace
 
-# version compatibility configuration
-__compat__ = SimpleNamespace()
-__compat__.__doc__ = """
+
+class __config_flags:
+    """Internal class for defining compatibility and debugging flags"""
+    _all_names = []
+    _fixed_names = []
+    _type_desc = "configuration"
+
+    @classmethod
+    def _set(cls, dname, value):
+        if dname in cls._fixed_names:
+            warnings.warn("{}.{} {} is {} and cannot be overridden".format(cls.__name__,
+                                                                               dname,
+                                                                               cls._type_desc,
+                                                                               str(getattr(cls, dname)).upper()))
+        if dname in cls._all_names:
+            setattr(cls, dname, value)
+        else:
+            raise ValueError("no such {} {!r}".format(cls._type_desc, dname))
+
+    enable = classmethod(lambda cls, name: cls._set(name, True))
+    disable = classmethod(lambda cls, name: cls._set(name, False))
+
+class __compat__(__config_flags):
+    """
     A cross-version compatibility configuration for pyparsing features that will be
     released in a future version. By setting values in this configuration to True,
     those features can be enabled in prior versions for compatibility development
     and testing.
 
      - collect_all_And_tokens - flag to enable fix for Issue #63 that fixes erroneous grouping
-       of results names when an And expression is nested within an Or or MatchFirst; 
+       of results names when an And expression is nested within an Or or MatchFirst;
        maintained for compatibility, but setting to False no longer restores pre-2.3.1
        behavior
-"""
-__compat__.collect_all_And_tokens = True
+    """
+    _type_desc = "compatibility"
+
+    collect_all_And_tokens = True
 
-__diag__ = SimpleNamespace()
-__diag__.__doc__ = """
-Diagnostic configuration (all default to False)
+    _all_names = [__ for __ in locals() if not __.startswith('_')]
+    _fixed_names = """
+        collect_all_And_tokens
+        """.split()
+
+class __diag__(__config_flags):
+    """
+    Diagnostic configuration (all default to False)
      - warn_multiple_tokens_in_named_alternation - flag to enable warnings when a results
        name is defined on a MatchFirst or Or expression with one or more And subexpressions
      - warn_ungrouped_named_tokens_in_collection - flag to enable warnings when a results
@@ -156,12 +184,27 @@ Diagnostic configuration (all default to False)
        incorrectly called with multiple str arguments
      - enable_debug_on_named_expressions - flag to auto-enable debug on all subsequent
        calls to ParserElement.setName()
-"""
-__diag__.warn_multiple_tokens_in_named_alternation = False
-__diag__.warn_ungrouped_named_tokens_in_collection = False
-__diag__.warn_name_set_on_empty_Forward = False
-__diag__.warn_on_multiple_string_args_to_oneof = False
-__diag__.enable_debug_on_named_expressions = False
+    """
+    _type_desc = "diagnostic"
+
+    warn_multiple_tokens_in_named_alternation = False
+    warn_ungrouped_named_tokens_in_collection = False
+    warn_name_set_on_empty_Forward = False
+    warn_on_multiple_string_args_to_oneof = False
+    enable_debug_on_named_expressions = False
+
+    _all_names = [__ for __ in locals() if not __.startswith('_')]
+    _warning_names = [name for name in _all_names if name.startswith("warn")]
+    _debug_names = [name for name in _all_names if name.startswith("enable_debug")]
+
+    @classmethod
+    def enable_all_warnings(cls):
+        for name in cls._warning_names:
+            cls.enable(name)
+
+# hide abstract class
+del __config_flags
+
 
 # ~ sys.stderr.write("testing pyparsing module, version %s, %s\n" % (__version__, __versionTime__))