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-rw-r--r--jython-tosca-parser/src/main/resources/Lib/site-packages/_markerlib/markers.py119
1 files changed, 119 insertions, 0 deletions
diff --git a/jython-tosca-parser/src/main/resources/Lib/site-packages/_markerlib/markers.py b/jython-tosca-parser/src/main/resources/Lib/site-packages/_markerlib/markers.py
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+++ b/jython-tosca-parser/src/main/resources/Lib/site-packages/_markerlib/markers.py
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+# -*- coding: utf-8 -*-
+"""Interpret PEP 345 environment markers.
+
+EXPR [in|==|!=|not in] EXPR [or|and] ...
+
+where EXPR belongs to any of those:
+
+ python_version = '%s.%s' % (sys.version_info[0], sys.version_info[1])
+ python_full_version = sys.version.split()[0]
+ os.name = os.name
+ sys.platform = sys.platform
+ platform.version = platform.version()
+ platform.machine = platform.machine()
+ platform.python_implementation = platform.python_implementation()
+ a free string, like '2.6', or 'win32'
+"""
+
+__all__ = ['default_environment', 'compile', 'interpret']
+
+import ast
+import os
+import platform
+import sys
+import weakref
+
+_builtin_compile = compile
+
+try:
+ from platform import python_implementation
+except ImportError:
+ if os.name == "java":
+ # Jython 2.5 has ast module, but not platform.python_implementation() function.
+ def python_implementation():
+ return "Jython"
+ else:
+ raise
+
+
+# restricted set of variables
+_VARS = {'sys.platform': sys.platform,
+ 'python_version': '%s.%s' % sys.version_info[:2],
+ # FIXME parsing sys.platform is not reliable, but there is no other
+ # way to get e.g. 2.7.2+, and the PEP is defined with sys.version
+ 'python_full_version': sys.version.split(' ', 1)[0],
+ 'os.name': os.name,
+ 'platform.version': platform.version(),
+ 'platform.machine': platform.machine(),
+ 'platform.python_implementation': python_implementation(),
+ 'extra': None # wheel extension
+ }
+
+for var in list(_VARS.keys()):
+ if '.' in var:
+ _VARS[var.replace('.', '_')] = _VARS[var]
+
+def default_environment():
+ """Return copy of default PEP 385 globals dictionary."""
+ return dict(_VARS)
+
+class ASTWhitelist(ast.NodeTransformer):
+ def __init__(self, statement):
+ self.statement = statement # for error messages
+
+ ALLOWED = (ast.Compare, ast.BoolOp, ast.Attribute, ast.Name, ast.Load, ast.Str)
+ # Bool operations
+ ALLOWED += (ast.And, ast.Or)
+ # Comparison operations
+ ALLOWED += (ast.Eq, ast.Gt, ast.GtE, ast.In, ast.Is, ast.IsNot, ast.Lt, ast.LtE, ast.NotEq, ast.NotIn)
+
+ def visit(self, node):
+ """Ensure statement only contains allowed nodes."""
+ if not isinstance(node, self.ALLOWED):
+ raise SyntaxError('Not allowed in environment markers.\n%s\n%s' %
+ (self.statement,
+ (' ' * node.col_offset) + '^'))
+ return ast.NodeTransformer.visit(self, node)
+
+ def visit_Attribute(self, node):
+ """Flatten one level of attribute access."""
+ new_node = ast.Name("%s.%s" % (node.value.id, node.attr), node.ctx)
+ return ast.copy_location(new_node, node)
+
+def parse_marker(marker):
+ tree = ast.parse(marker, mode='eval')
+ new_tree = ASTWhitelist(marker).generic_visit(tree)
+ return new_tree
+
+def compile_marker(parsed_marker):
+ return _builtin_compile(parsed_marker, '<environment marker>', 'eval',
+ dont_inherit=True)
+
+_cache = weakref.WeakValueDictionary()
+
+def compile(marker):
+ """Return compiled marker as a function accepting an environment dict."""
+ try:
+ return _cache[marker]
+ except KeyError:
+ pass
+ if not marker.strip():
+ def marker_fn(environment=None, override=None):
+ """"""
+ return True
+ else:
+ compiled_marker = compile_marker(parse_marker(marker))
+ def marker_fn(environment=None, override=None):
+ """override updates environment"""
+ if override is None:
+ override = {}
+ if environment is None:
+ environment = default_environment()
+ environment.update(override)
+ return eval(compiled_marker, environment)
+ marker_fn.__doc__ = marker
+ _cache[marker] = marker_fn
+ return _cache[marker]
+
+def interpret(marker, environment=None):
+ return compile(marker)(environment)