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@@ -1,302 +1,305 b'' | |||
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1 | 1 | # demandimport.py - global demand-loading of modules for Mercurial |
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2 | 2 | # |
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3 | 3 | # Copyright 2006, 2007 Matt Mackall <mpm@selenic.com> |
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4 | 4 | # |
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5 | 5 | # This software may be used and distributed according to the terms of the |
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6 | 6 | # GNU General Public License version 2 or any later version. |
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7 | 7 | |
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8 | 8 | ''' |
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9 | 9 | demandimport - automatic demandloading of modules |
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10 | 10 | |
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11 | 11 | To enable this module, do: |
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12 | 12 | |
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13 | 13 | import demandimport; demandimport.enable() |
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14 | 14 | |
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15 | 15 | Imports of the following forms will be demand-loaded: |
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16 | 16 | |
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17 | 17 | import a, b.c |
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18 | 18 | import a.b as c |
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19 | 19 | from a import b,c # a will be loaded immediately |
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20 | 20 | |
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21 | 21 | These imports will not be delayed: |
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22 | 22 | |
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23 | 23 | from a import * |
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24 | 24 | b = __import__(a) |
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25 | 25 | ''' |
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26 | 26 | |
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27 | 27 | from __future__ import absolute_import |
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28 | 28 | |
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29 | 29 | import contextlib |
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30 | 30 | import os |
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31 | 31 | import sys |
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32 | 32 | |
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33 | 33 | # __builtin__ in Python 2, builtins in Python 3. |
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34 | 34 | try: |
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35 | 35 | import __builtin__ as builtins |
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36 | 36 | except ImportError: |
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37 | 37 | import builtins |
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38 | 38 | |
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39 | 39 | contextmanager = contextlib.contextmanager |
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40 | 40 | |
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41 | 41 | _origimport = __import__ |
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42 | 42 | |
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43 | 43 | nothing = object() |
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44 | 44 | |
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45 | 45 | # Python 3 doesn't have relative imports nor level -1. |
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46 | 46 | level = -1 |
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47 | 47 | if sys.version_info[0] >= 3: |
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48 | 48 | level = 0 |
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49 | 49 | _import = _origimport |
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50 | 50 | |
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51 | 51 | def _hgextimport(importfunc, name, globals, *args, **kwargs): |
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52 | 52 | try: |
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53 | 53 | return importfunc(name, globals, *args, **kwargs) |
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54 | 54 | except ImportError: |
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55 | 55 | if not globals: |
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56 | 56 | raise |
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57 | 57 | # extensions are loaded with "hgext_" prefix |
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58 | 58 | hgextname = 'hgext_%s' % name |
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59 | 59 | nameroot = hgextname.split('.', 1)[0] |
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60 | 60 | contextroot = globals.get('__name__', '').split('.', 1)[0] |
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61 | 61 | if nameroot != contextroot: |
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62 | 62 | raise |
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63 | 63 | # retry to import with "hgext_" prefix |
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64 | 64 | return importfunc(hgextname, globals, *args, **kwargs) |
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65 | 65 | |
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66 | 66 | class _demandmod(object): |
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67 | 67 | """module demand-loader and proxy |
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68 | 68 | |
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69 | 69 | Specify 1 as 'level' argument at construction, to import module |
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70 | 70 | relatively. |
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71 | 71 | """ |
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72 | 72 | |
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73 | 73 | def __init__(self, name, globals, locals, level): |
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74 | 74 | if '.' in name: |
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75 | 75 | head, rest = name.split('.', 1) |
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76 | 76 | after = [rest] |
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77 | 77 | else: |
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78 | 78 | head = name |
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79 | 79 | after = [] |
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80 | 80 | object.__setattr__(self, r"_data", |
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81 | 81 | (head, globals, locals, after, level, set())) |
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82 | 82 | object.__setattr__(self, r"_module", None) |
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83 | 83 | |
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84 | 84 | def _extend(self, name): |
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85 | 85 | """add to the list of submodules to load""" |
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86 | 86 | self._data[3].append(name) |
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87 | 87 | |
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88 | 88 | def _addref(self, name): |
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89 | 89 | """Record that the named module ``name`` imports this module. |
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90 | 90 | |
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91 | 91 | References to this proxy class having the name of this module will be |
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92 | 92 | replaced at module load time. We assume the symbol inside the importing |
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93 | 93 | module is identical to the "head" name of this module. We don't |
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94 | 94 | actually know if "as X" syntax is being used to change the symbol name |
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95 | 95 | because this information isn't exposed to __import__. |
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96 | 96 | """ |
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97 | 97 | self._data[5].add(name) |
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98 | 98 | |
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99 | 99 | def _load(self): |
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100 | 100 | if not self._module: |
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101 | 101 | head, globals, locals, after, level, modrefs = self._data |
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102 | 102 | mod = _hgextimport(_import, head, globals, locals, None, level) |
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103 | 103 | if mod is self: |
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104 | 104 | # In this case, _hgextimport() above should imply |
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105 | 105 | # _demandimport(). Otherwise, _hgextimport() never |
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106 | 106 | # returns _demandmod. This isn't intentional behavior, |
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107 | 107 | # in fact. (see also issue5304 for detail) |
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108 | 108 | # |
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109 | 109 | # If self._module is already bound at this point, self |
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110 | 110 | # should be already _load()-ed while _hgextimport(). |
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111 | 111 | # Otherwise, there is no way to import actual module |
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112 | 112 | # as expected, because (re-)invoking _hgextimport() |
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113 | 113 | # should cause same result. |
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114 | 114 | # This is reason why _load() returns without any more |
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115 | 115 | # setup but assumes self to be already bound. |
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116 | 116 | mod = self._module |
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117 | 117 | assert mod and mod is not self, "%s, %s" % (self, mod) |
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118 | 118 | return |
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119 | 119 | |
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120 | 120 | # load submodules |
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121 | 121 | def subload(mod, p): |
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122 | 122 | h, t = p, None |
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123 | 123 | if '.' in p: |
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124 | 124 | h, t = p.split('.', 1) |
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125 | 125 | if getattr(mod, h, nothing) is nothing: |
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126 | 126 | setattr(mod, h, _demandmod(p, mod.__dict__, mod.__dict__, |
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127 | 127 | level=1)) |
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128 | 128 | elif t: |
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129 | 129 | subload(getattr(mod, h), t) |
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130 | 130 | |
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131 | 131 | for x in after: |
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132 | 132 | subload(mod, x) |
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133 | 133 | |
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134 | 134 | # Replace references to this proxy instance with the actual module. |
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135 |
if locals |
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136 |
locals |
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135 | if locals: | |
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136 | if locals.get(head) is self: | |
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137 | locals[head] = mod | |
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138 | elif locals.get(head + r'mod') is self: | |
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139 | locals[head + r'mod'] = mod | |
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137 | 140 | |
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138 | 141 | for modname in modrefs: |
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139 | 142 | modref = sys.modules.get(modname, None) |
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140 | 143 | if modref and getattr(modref, head, None) is self: |
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141 | 144 | setattr(modref, head, mod) |
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142 | 145 | |
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143 | 146 | object.__setattr__(self, r"_module", mod) |
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144 | 147 | |
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145 | 148 | def __repr__(self): |
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146 | 149 | if self._module: |
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147 | 150 | return "<proxied module '%s'>" % self._data[0] |
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148 | 151 | return "<unloaded module '%s'>" % self._data[0] |
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149 | 152 | |
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150 | 153 | def __call__(self, *args, **kwargs): |
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151 | 154 | raise TypeError("%s object is not callable" % repr(self)) |
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152 | 155 | |
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153 | 156 | def __getattribute__(self, attr): |
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154 | 157 | if attr in ('_data', '_extend', '_load', '_module', '_addref'): |
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155 | 158 | return object.__getattribute__(self, attr) |
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156 | 159 | self._load() |
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157 | 160 | return getattr(self._module, attr) |
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158 | 161 | |
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159 | 162 | def __setattr__(self, attr, val): |
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160 | 163 | self._load() |
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161 | 164 | setattr(self._module, attr, val) |
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162 | 165 | |
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163 | 166 | _pypy = '__pypy__' in sys.builtin_module_names |
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164 | 167 | |
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165 | 168 | def _demandimport(name, globals=None, locals=None, fromlist=None, level=level): |
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166 | 169 | if locals is None or name in ignore or fromlist == ('*',): |
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167 | 170 | # these cases we can't really delay |
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168 | 171 | return _hgextimport(_import, name, globals, locals, fromlist, level) |
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169 | 172 | elif not fromlist: |
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170 | 173 | # import a [as b] |
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171 | 174 | if '.' in name: # a.b |
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172 | 175 | base, rest = name.split('.', 1) |
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173 | 176 | # email.__init__ loading email.mime |
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174 | 177 | if globals and globals.get('__name__', None) == base: |
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175 | 178 | return _import(name, globals, locals, fromlist, level) |
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176 | 179 | # if a is already demand-loaded, add b to its submodule list |
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177 | 180 | if base in locals: |
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178 | 181 | if isinstance(locals[base], _demandmod): |
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179 | 182 | locals[base]._extend(rest) |
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180 | 183 | return locals[base] |
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181 | 184 | return _demandmod(name, globals, locals, level) |
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182 | 185 | else: |
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183 | 186 | # There is a fromlist. |
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184 | 187 | # from a import b,c,d |
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185 | 188 | # from . import b,c,d |
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186 | 189 | # from .a import b,c,d |
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187 | 190 | |
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188 | 191 | # level == -1: relative and absolute attempted (Python 2 only). |
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189 | 192 | # level >= 0: absolute only (Python 2 w/ absolute_import and Python 3). |
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190 | 193 | # The modern Mercurial convention is to use absolute_import everywhere, |
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191 | 194 | # so modern Mercurial code will have level >= 0. |
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192 | 195 | |
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193 | 196 | # The name of the module the import statement is located in. |
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194 | 197 | globalname = globals.get('__name__') |
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195 | 198 | |
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196 | 199 | def processfromitem(mod, attr): |
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197 | 200 | """Process an imported symbol in the import statement. |
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198 | 201 | |
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199 | 202 | If the symbol doesn't exist in the parent module, and if the |
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200 | 203 | parent module is a package, it must be a module. We set missing |
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201 | 204 | modules up as _demandmod instances. |
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202 | 205 | """ |
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203 | 206 | symbol = getattr(mod, attr, nothing) |
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204 | 207 | nonpkg = getattr(mod, '__path__', nothing) is nothing |
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205 | 208 | if symbol is nothing: |
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206 | 209 | if nonpkg: |
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207 | 210 | # do not try relative import, which would raise ValueError, |
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208 | 211 | # and leave unknown attribute as the default __import__() |
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209 | 212 | # would do. the missing attribute will be detected later |
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210 | 213 | # while processing the import statement. |
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211 | 214 | return |
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212 | 215 | mn = '%s.%s' % (mod.__name__, attr) |
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213 | 216 | if mn in ignore: |
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214 | 217 | importfunc = _origimport |
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215 | 218 | else: |
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216 | 219 | importfunc = _demandmod |
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217 | 220 | symbol = importfunc(attr, mod.__dict__, locals, level=1) |
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218 | 221 | setattr(mod, attr, symbol) |
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219 | 222 | |
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220 | 223 | # Record the importing module references this symbol so we can |
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221 | 224 | # replace the symbol with the actual module instance at load |
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222 | 225 | # time. |
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223 | 226 | if globalname and isinstance(symbol, _demandmod): |
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224 | 227 | symbol._addref(globalname) |
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225 | 228 | |
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226 | 229 | def chainmodules(rootmod, modname): |
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227 | 230 | # recurse down the module chain, and return the leaf module |
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228 | 231 | mod = rootmod |
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229 | 232 | for comp in modname.split('.')[1:]: |
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230 | 233 | if getattr(mod, comp, nothing) is nothing: |
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231 | 234 | setattr(mod, comp, _demandmod(comp, mod.__dict__, |
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232 | 235 | mod.__dict__, level=1)) |
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233 | 236 | mod = getattr(mod, comp) |
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234 | 237 | return mod |
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235 | 238 | |
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236 | 239 | if level >= 0: |
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237 | 240 | if name: |
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238 | 241 | # "from a import b" or "from .a import b" style |
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239 | 242 | rootmod = _hgextimport(_origimport, name, globals, locals, |
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240 | 243 | level=level) |
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241 | 244 | mod = chainmodules(rootmod, name) |
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242 | 245 | elif _pypy: |
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243 | 246 | # PyPy's __import__ throws an exception if invoked |
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244 | 247 | # with an empty name and no fromlist. Recreate the |
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245 | 248 | # desired behaviour by hand. |
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246 | 249 | mn = globalname |
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247 | 250 | mod = sys.modules[mn] |
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248 | 251 | if getattr(mod, '__path__', nothing) is nothing: |
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249 | 252 | mn = mn.rsplit('.', 1)[0] |
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250 | 253 | mod = sys.modules[mn] |
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251 | 254 | if level > 1: |
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252 | 255 | mn = mn.rsplit('.', level - 1)[0] |
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253 | 256 | mod = sys.modules[mn] |
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254 | 257 | else: |
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255 | 258 | mod = _hgextimport(_origimport, name, globals, locals, |
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256 | 259 | level=level) |
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257 | 260 | |
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258 | 261 | for x in fromlist: |
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259 | 262 | processfromitem(mod, x) |
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260 | 263 | |
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261 | 264 | return mod |
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262 | 265 | |
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263 | 266 | # But, we still need to support lazy loading of standard library and 3rd |
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264 | 267 | # party modules. So handle level == -1. |
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265 | 268 | mod = _hgextimport(_origimport, name, globals, locals) |
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266 | 269 | mod = chainmodules(mod, name) |
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267 | 270 | |
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268 | 271 | for x in fromlist: |
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269 | 272 | processfromitem(mod, x) |
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270 | 273 | |
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271 | 274 | return mod |
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272 | 275 | |
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273 | 276 | ignore = [] |
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274 | 277 | |
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275 | 278 | def init(ignorelist): |
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276 | 279 | global ignore |
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277 | 280 | ignore = ignorelist |
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278 | 281 | |
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279 | 282 | def isenabled(): |
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280 | 283 | return builtins.__import__ == _demandimport |
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281 | 284 | |
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282 | 285 | def enable(): |
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283 | 286 | "enable global demand-loading of modules" |
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284 | 287 | if os.environ.get('HGDEMANDIMPORT') != 'disable': |
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285 | 288 | builtins.__import__ = _demandimport |
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286 | 289 | |
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287 | 290 | def disable(): |
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288 | 291 | "disable global demand-loading of modules" |
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289 | 292 | builtins.__import__ = _origimport |
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290 | 293 | |
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291 | 294 | @contextmanager |
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292 | 295 | def deactivated(): |
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293 | 296 | "context manager for disabling demandimport in 'with' blocks" |
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294 | 297 | demandenabled = isenabled() |
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295 | 298 | if demandenabled: |
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296 | 299 | disable() |
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297 | 300 | |
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298 | 301 | try: |
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299 | 302 | yield |
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300 | 303 | finally: |
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301 | 304 | if demandenabled: |
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302 | 305 | enable() |
@@ -1,89 +1,95 b'' | |||
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1 | 1 | from __future__ import print_function |
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2 | 2 | |
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3 | 3 | from mercurial import demandimport |
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4 | 4 | demandimport.enable() |
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5 | 5 | |
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6 | 6 | import os |
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7 | 7 | import subprocess |
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8 | 8 | import sys |
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9 | 9 | |
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10 | 10 | # Only run if demandimport is allowed |
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11 | 11 | if subprocess.call(['python', '%s/hghave' % os.environ['TESTDIR'], |
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12 | 12 | 'demandimport']): |
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13 | 13 | sys.exit(80) |
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14 | 14 | |
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15 | 15 | if os.name != 'nt': |
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16 | 16 | try: |
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17 | 17 | import distutils.msvc9compiler |
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18 | 18 | print('distutils.msvc9compiler needs to be an immediate ' |
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19 | 19 | 'importerror on non-windows platforms') |
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20 | 20 | distutils.msvc9compiler |
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21 | 21 | except ImportError: |
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22 | 22 | pass |
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23 | 23 | |
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24 | 24 | import re |
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25 | 25 | |
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26 | 26 | rsub = re.sub |
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27 | 27 | def f(obj): |
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28 | 28 | l = repr(obj) |
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29 | 29 | l = rsub("0x[0-9a-fA-F]+", "0x?", l) |
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30 | 30 | l = rsub("from '.*'", "from '?'", l) |
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31 | 31 | l = rsub("'<[a-z]*>'", "'<whatever>'", l) |
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32 | 32 | return l |
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33 | 33 | |
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34 | 34 | import os |
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35 | 35 | |
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36 | 36 | print("os =", f(os)) |
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37 | 37 | print("os.system =", f(os.system)) |
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38 | 38 | print("os =", f(os)) |
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39 | 39 | |
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40 | 40 | from mercurial import util |
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41 | 41 | |
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42 | 42 | print("util =", f(util)) |
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43 | 43 | print("util.system =", f(util.system)) |
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44 | 44 | print("util =", f(util)) |
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45 | 45 | print("util.system =", f(util.system)) |
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46 | 46 | |
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47 | 47 | from mercurial import hgweb |
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48 | 48 | print("hgweb =", f(hgweb)) |
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49 | 49 | print("hgweb_mod =", f(hgweb.hgweb_mod)) |
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50 | 50 | print("hgweb =", f(hgweb)) |
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51 | 51 | |
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52 | 52 | import re as fred |
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53 | 53 | print("fred =", f(fred)) |
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54 | 54 | |
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55 | import re as remod | |
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56 | print("remod =", f(remod)) | |
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57 | ||
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55 | 58 | import sys as re |
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56 | 59 | print("re =", f(re)) |
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57 | 60 | |
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58 | 61 | print("fred =", f(fred)) |
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59 | 62 | print("fred.sub =", f(fred.sub)) |
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60 | 63 | print("fred =", f(fred)) |
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61 | 64 | |
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65 | remod.escape # use remod | |
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66 | print("remod =", f(remod)) | |
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67 | ||
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62 | 68 | print("re =", f(re)) |
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63 | 69 | print("re.stderr =", f(re.stderr)) |
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64 | 70 | print("re =", f(re)) |
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65 | 71 | |
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66 | 72 | import contextlib |
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67 | 73 | print("contextlib =", f(contextlib)) |
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68 | 74 | try: |
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69 | 75 | from contextlib import unknownattr |
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70 | 76 | print('no demandmod should be created for attribute of non-package ' |
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71 | 77 | 'module:\ncontextlib.unknownattr =', f(unknownattr)) |
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72 | 78 | except ImportError as inst: |
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73 | 79 | print('contextlib.unknownattr = ImportError: %s' |
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74 | 80 | % rsub(r"'", '', str(inst))) |
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75 | 81 | |
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76 | 82 | # Unlike the import statement, __import__() function should not raise |
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77 | 83 | # ImportError even if fromlist has an unknown item |
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78 | 84 | # (see Python/import.c:import_module_level() and ensure_fromlist()) |
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79 | 85 | contextlibimp = __import__('contextlib', globals(), locals(), ['unknownattr']) |
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80 | 86 | print("__import__('contextlib', ..., ['unknownattr']) =", f(contextlibimp)) |
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81 | 87 | print("hasattr(contextlibimp, 'unknownattr') =", |
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82 | 88 | util.safehasattr(contextlibimp, 'unknownattr')) |
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83 | 89 | |
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84 | 90 | demandimport.disable() |
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85 | 91 | os.environ['HGDEMANDIMPORT'] = 'disable' |
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86 | 92 | # this enable call should not actually enable demandimport! |
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87 | 93 | demandimport.enable() |
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88 | 94 | from mercurial import node |
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89 | 95 | print("node =", f(node)) |
@@ -1,23 +1,25 b'' | |||
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1 | 1 | os = <unloaded module 'os'> |
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2 | 2 | os.system = <built-in function system> |
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3 | 3 | os = <module 'os' from '?'> |
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4 | 4 | util = <unloaded module 'util'> |
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5 | 5 | util.system = <function system at 0x?> |
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6 | 6 | util = <module 'mercurial.util' from '?'> |
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7 | 7 | util.system = <function system at 0x?> |
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8 | 8 | hgweb = <unloaded module 'hgweb'> |
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9 | 9 | hgweb_mod = <unloaded module 'hgweb_mod'> |
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10 | 10 | hgweb = <module 'mercurial.hgweb' from '?'> |
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11 | 11 | fred = <unloaded module 're'> |
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12 | remod = <unloaded module 're'> | |
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12 | 13 | re = <unloaded module 'sys'> |
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13 | 14 | fred = <unloaded module 're'> |
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14 | 15 | fred.sub = <function sub at 0x?> |
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15 | 16 | fred = <proxied module 're'> |
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17 | remod = <module 're' from '?'> | |
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16 | 18 | re = <unloaded module 'sys'> |
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17 | 19 | re.stderr = <open file '<whatever>', mode 'w' at 0x?> |
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18 | 20 | re = <proxied module 'sys'> |
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19 | 21 | contextlib = <unloaded module 'contextlib'> |
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20 | 22 | contextlib.unknownattr = ImportError: cannot import name unknownattr |
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21 | 23 | __import__('contextlib', ..., ['unknownattr']) = <module 'contextlib' from '?'> |
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22 | 24 | hasattr(contextlibimp, 'unknownattr') = False |
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23 | 25 | node = <module 'mercurial.node' from '?'> |
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