Source Code for Module base

  1  #!/usr/bin/python3 
  2  """ This module implements the base class for almost everything""" 
  3   
  4   
  5 -class Base(object): 
  6      """ 
  7      This is the base class for all other classes 
  8   
  9      @ivar name:         name of this object 
 10      @ivar description:  one line this description 
 11      @ivar attributes:   dict of <name,value> pairs" 
 12      """ 
 13   
 14 -    def __init__(self, name, descr=None): 
 15          """ 
 16          create a new object 
 17          @param name: display name of this object 
 18          @param descr: human description of this object 
 19          """ 
 20          self.name = name 
 21          self.description = descr 
 22          self.attributes = {} 
 23   
 24 -    def __str__(self): 
 25          """ 
 26          return a descriptive string for this object 
 27          """ 
 28          if self.description is None: 
 29              return self.name 
 30          return "{}({})".format(self.name, self.description) 
 31   
 32 -    def get(self, attribute): 
 33          """ 
 34          return: value of an attribute 
 35   
 36          @param attribute: name of attribute to be fetched 
 37          @return: (string) value (or none) 
 38          """ 
 39          if attribute in self.attributes: 
 40              return self.attributes[attribute] 
 41          return None 
 42   
 43 -    def set(self, attribute, value): 
 44          """ 
 45          set the value of an attribute 
 46   
 47          @param attribute: name of attribute to be fetched 
 48          @param value: value to be stored for that attribute 
 49          """ 
 50          self.attributes[attribute] = value 
 51   
 52   
 53  # UNIT TESTING 
 54 -def main(): 
 55      """ 
 56      basic test cases for name, description, and attributes 
 57      """ 
 58   
 59      describe = "simple get/set test object" 
 60      go1 = Base("Base Object 1", describe) 
 61      go2 = Base("Base Object 2") 
 62   
 63      tried = 0 
 64      passed = 0 
 65   
 66      # new object has name, description, and nothing else 
 67      print("Created 'Base 1', descr={}\n    got '{}'" 
 68            .format(describe, str(go1))) 
 69      tried += 2 
 70      assert (go1.name == "Base Object 1"), \ 
 71          "New object does not have assigned name" 
 72      assert (go1.description == describe), \ 
 73          "New object does not have assigned description" 
 74      passed += 2 
 75   
 76      # a new set correctly adds a value 
 77      print("    before set(): get('attribute#1') -> {}" 
 78            .format(go1.get("attribute#1"))) 
 79      tried += 2 
 80      assert (go1.get("attribute#1") is None), \ 
 81          "New object has attribute values before set" 
 82      go1.set("attribute#1", "value1") 
 83      print("    after set('attribute#1', 'value1'): get('attribute#1') -> '{}'" 
 84            .format(go1.get("attribute#1"))) 
 85      assert (go1.get("attribute#1") == "value1"), \ 
 86          "set does not correctly set new value" 
 87      passed += 2 
 88   
 89      # a second set correctly changes a value 
 90      go1.set("attribute#1", "value2") 
 91      print("    after set('attribute#1', 'value2'): get('attribute#1') -> '{}'" 
 92            .format(go1.get("attribute#1"))) 
 93      tried += 1 
 94      assert (go1.get("attribute#1") == "value2"), \ 
 95          "set does not correctly change value" 
 96      passed += 1 
 97   
 98      # description defaults to None 
 99      print("Created 'Base Object 2, descr=None\n    got '{}'" 
100            .format(str(go2))) 
101      tried += 2 
102      assert (go2.name == "Base Object 2"), \ 
103          "New object does not have assigned name" 
104      assert (go2.description is None), \ 
105          "New description does not default to None" 
106      passed += 2 
107   
108      print() 
109      if tried == passed: 
110          print("Passed all {} Base tests".format(passed)) 
111      else: 
112          print("FAILED {}/{} Base tests".format(tried-passed, tried)) 
113   
114   
115  if __name__ == "__main__": 
116      main() 
117