test.examples_default source code

1 /**
2 The following examples come from
3 $(LINK http://zetcode.com/db/sqlite/constraints/).
4 Even though it is a SQLite tutorial the point is to show how to use this package
5 which does not have to be just SQLite.
6  */
7 module test.examples_default;
8 
9 version(D_Ddoc)
10 {
11     ///
12     class BlankClassSoDocsWillBeGenerated { }
13 }
14 
15 
16 /**
17 This example is for the DEFAULT constraint. The table
18 in SQL can be created by
19 $(D $(D $(D sql
20 CREATE TABLE Hotels
21 (
22     Id INTEGER NOT NULL PRIMARY KEY,
23     Name TEXT,
24     City TEXT DEFAULT 'not available'
25 );
26 
27 )))
28 
29 Default in this package was made for foreign key interactions. With that
30 in mind I know in this example it seems like I should just set
31 the default value in the setter but then my package would not know what
32 default you want for a foreign key update rule or delete rule.
33  */
34 unittest
35 {
36     import db_constraints;
37 
38     class Hotel
39     {
40         private int _Id;
41         // marking Id with not null and primary key
42         @NotNull @PrimaryKeyColumn
43         @property int Id()
44         {
45             return _Id;
46         }
47         @property void Id(int value)
48         {
49             setter(_Id, value);
50         }
51 
52 
53         private string _Name;
54         @property string Name()
55         {
56             return _Name;
57         }
58         @property void Name(string value)
59         {
60             setter(_Name, value);
61         }
62 
63         private string _City;
64         // marking city with its default
65         @Default!("not available")
66         @property string City()
67         {
68             return _City;
69         }
70         @property void City(string value)
71         {
72             setter(_City, value);
73         }
74 
75         this(int Id_, string Name_, string City_)
76         {
77             this._Id = Id_;
78             this._Name = Name_;
79             this._City = City_;
80             initializeKeyedItem();
81         }
82         this(int Id_, string Name_)
83         {
84             this._Id = Id_;
85             this._Name = Name_;
86             // using GetDefault will get the value you
87             // placed in the Default attribute
88             this._City = GetDefault!(Hotel, "City");
89             initializeKeyedItem();
90         }
91 
92         mixin KeyedItem!();
93     }
94 
95     // make sure Hotel.City has a default attribute
96     assert(hasDefault!(Hotel, "City"));
97     // the default attribute has value not available
98     assert(GetDefault!(Hotel, "City") == "not available");
99 
100     auto i = new Hotel(1, "Kyjev", "Bratislava");
101     assert(i.City == "Bratislava");
102     // since City is not included in this constructor we use the default
103     auto j = new Hotel(2, "Slovan");
104     assert(j.City == "not available");
105 }