Lib/test/test_linecache.py

   1 """ Tests for the linecache module """
   2
   3 import linecache
   4 import unittest
   5 import os.path
   6 from test import test_support as support
   7
   8
   9 FILENAME = linecache.__file__
  10 INVALID_NAME = '!@$)(!@#_1'
  11 EMPTY = ''
  12 TESTS = 'cjkencodings_test inspect_fodder inspect_fodder2 mapping_tests'
  13 TESTS = TESTS.split()
  14 TEST_PATH = os.path.dirname(support.__file__)
  15 MODULES = "linecache abc".split()
  16 MODULE_PATH = os.path.dirname(FILENAME)
  17
  18 SOURCE_1 = '''
  19 " Docstring "
  20
  21 def function():
  22     return result
  23
  24 '''
  25
  26 SOURCE_2 = '''
  27 def f():
  28     return 1 + 1
  29
  30 a = f()
  31
  32 '''
  33
  34 class LineCacheTests(unittest.TestCase):
  35
  36     def test_getline(self):
  37         getline = linecache.getline
  38
  39         # Bad values for line number should return an empty string
  40         self.assertEquals(getline(FILENAME, 2**15), EMPTY)
  41         self.assertEquals(getline(FILENAME, -1), EMPTY)
  42
  43         # Float values currently raise TypeError, should it?
  44         self.assertRaises(TypeError, getline, FILENAME, 1.1)
  45
  46         # Bad filenames should return an empty string
  47         self.assertEquals(getline(EMPTY, 1), EMPTY)
  48         self.assertEquals(getline(INVALID_NAME, 1), EMPTY)
  49
  50         # Check whether lines correspond to those from file iteration
  51         for entry in TESTS:
  52             filename = os.path.join(TEST_PATH, entry) + '.py'
  53             for index, line in enumerate(open(filename)):
  54                 self.assertEquals(line, getline(filename, index + 1))
  55
  56         # Check module loading
  57         for entry in MODULES:
  58             filename = os.path.join(MODULE_PATH, entry) + '.py'
  59             for index, line in enumerate(open(filename)):
  60                 self.assertEquals(line, getline(filename, index + 1))
  61
  62         # Check that bogus data isn't returned (issue #1309567)
  63         empty = linecache.getlines('a/b/c/__init__.py')
  64         self.assertEquals(empty, [])
  65
  66     def test_clearcache(self):
  67         cached = []
  68         for entry in TESTS:
  69             filename = os.path.join(TEST_PATH, entry) + '.py'
  70             cached.append(filename)
  71             linecache.getline(filename, 1)
  72
  73         # Are all files cached?
  74         cached_empty = [fn for fn in cached if fn not in linecache.cache]
  75         self.assertEquals(cached_empty, [])
  76
  77         # Can we clear the cache?
  78         linecache.clearcache()
  79         cached_empty = [fn for fn in cached if fn in linecache.cache]
  80         self.assertEquals(cached_empty, [])
  81
  82     def test_checkcache(self):
  83         getline = linecache.getline
  84         try:
  85             # Create a source file and cache its contents
  86             source_name = support.TESTFN + '.py'
  87             with open(source_name, 'w') as source:
  88                 source.write(SOURCE_1)
  89                 source.close()
  90                 getline(source_name, 1)
  91
  92                 # Keep a copy of the old contents
  93                 source_list = []
  94                 source = open(source_name)
  95                 for index, line in enumerate(source):
  96                     self.assertEquals(line, getline(source_name, index + 1))
  97                     source_list.append(line)
  98                 source.close()
  99
 100                 source = open(source_name, 'w')
 101                 source.write(SOURCE_2)
 102                 source.close()
 103
 104                 # Try to update a bogus cache entry
 105                 linecache.checkcache('dummy')
 106
 107                 # Check that the cache matches the old contents
 108                 for index, line in enumerate(source_list):
 109                     self.assertEquals(line, getline(source_name, index + 1))
 110
 111                 # Update the cache and check whether it matches the new source file
 112                 linecache.checkcache(source_name)
 113                 source = open(source_name)
 114                 for index, line in enumerate(source):
 115                     self.assertEquals(line, getline(source_name, index + 1))
 116                     source_list.append(line)
 117
 118         finally:
 119             support.unlink(source_name)
 120
 121 def test_main():
 122     support.run_unittest(LineCacheTests)
 123
 124 if __name__ == "__main__":
 125     test_main()