README-TestSuite
1This README file describes the files and directories related -*- rst -*-
2to the Python test suite under the current 'test' directory.
3
4- dotest.py
5
6 Provides the test driver for the test suite. To invoke it, cd to the 'test'
7 directory and issue the './dotest.py' command or './dotest.py -v' for more
8 verbose output. '.dotest.py -h' prints out the help messge.
9
10 A specific naming pattern is followed by the .py script under the 'test'
11 directory in order to be recognized by 'dotest.py' test driver as a module
12 which implements a test case, namely, Test*.py.
13
14 Some example usages:
15
16 1. ./dotest.py -v . 2> ~/Developer/Log/lldbtest.log0
17 This runs the test suite and directs the run log to a file.
18
19 2. LLDB_LOG=/tmp/lldb.log GDB_REMOTE_LOG=/tmp/gdb-remote.log ./dotest.py -v . 2> ~/Developer/Log/lldbtest.log
20 This runs the test suite, with logging turned on for the lldb as well as
21 the process.gdb-remote channels and directs the run log to a file.
22
23- lldbtest.py
24
25 Provides an abstract base class of lldb test case named 'TestBase', which in
26 turn inherits from Python's unittest.TestCase. The concrete subclass can
27 override lldbtest.TestBase in order to inherit the common behavior for
28 unittest.TestCase.setUp/tearDown implemented in this file.
29
30 To provide a test case, the concrete subclass provides methods whose names
31 start with the letters test. For more details about the Python's unittest
32 framework, go to http://docs.python.org/library/unittest.html.
33
34 ./command_source/TestCommandSource.py provides a simple example of test case
35 which overrides lldbtest.TestBase to exercise the lldb's 'command source'
36 command.
37
38 The doc string provides more details about the setup required for running a
39 test case on its own. To run the whole test suite, 'dotest.py' is all you
40 need to do.
41
42- subdirectories of 'test'
43
44 Most of them predate the introduction of the python test suite and contain
45 example C/C++/ObjC source files which get compiled into executables which are
46 to be exercised by the debugger.
47
48 For such subdirectory which has an associated Test*.py file, it was added as
49 part of the Python-based test suite to test lldb functionality.
50
51 Some of the subdirectories, for example, the 'help' subdirectory, do not have
52 C/C++/ObjC source files; they were created to house the Python test case which
53 does not involve lldb reading in an executable file at all.
54
55 The sample_test directory contains examples of both a full and an "inline"
56 testcase that run a process to a breakpoint and check a local variable. These
57 are convenient starting points for adding new tests.
58
59- make directory
60
61 Contains Makefile.rules, which can be utilized by test cases to write Makefile
62 based rules to build binaries for the inferiors.
63
64 By default, the built executable name is a.out, which can be overwritten by
65 specifying your EXE make variable, via the Makefile under the specific test
66 directory or via supplying a Python dictionary to the build method in your
67 Python test script. An example of the latter can be found in
68 test/lang/objc/radar-9691614/TestObjCMethodReturningBOOL.py, where:
69
70 def test_method_ret_BOOL(self):
71 """Test that objective-c method returning BOOL works correctly."""
72 d = {'EXE': self.exe_name}
73 self.build(dictionary=d)
74 self.setTearDownCleanup(dictionary=d)
75 ...
76
77 def setUp(self):
78 # Call super's setUp().
79 TestBase.setUp(self)
80 # We'll use the test method name as the exe_name.
81 self.exe_name = self.testMethodName
82 # Find the line number to break inside main().
83 self.main_source = "main.m"
84 self.line = line_number(self.main_source, '// Set breakpoint here.')
85
86 The exe names for the two test methods are equal to the test method names and
87 are therefore guaranteed different.
88
89- plugins directory
90
91 Contains platform specific plugin to build binaries with dsym/dwarf debugging
92 info. Other platform specific functionalities may be added in the future.
93
94- unittest2 directory
95
96 Many new features were added to unittest in Python 2.7, including test
97 discovery. unittest2 allows you to use these features with earlier versions of
98 Python.
99
100 It currently has unittest2 0.5.1 from http://pypi.python.org/pypi/unittest2.
101 Version 0.5.1 of unittest2 has feature parity with unittest in Python 2.7
102 final. If you want to ensure that your tests run identically under unittest2
103 and unittest in Python 2.7 you should use unittest2 0.5.1.
104
105 Later versions of unittest2 include changes in unittest made in Python 3.2 and
106 onwards after the release of Python 2.7.
107
108- dotest.pl
109
110 In case you wonder, there is also a 'dotest.pl' perl script file. It was
111 created to visit each Python test case under the specified directory and
112 invoke Python's builtin unittest.main() on each test case.
113
114 It does not take advantage of the test runner and test suite functionality
115 provided by Python's unitest framework. Its existence is because we want a
116 different way of running the whole test suite. As lldb and the Python test
117 suite become more reliable, we don't expect to be using 'dotest.pl' anymore.
118
119 Note: dotest.pl has been moved to the attic directory.
120
121- Profiling dotest.py runs
122
123 I used the following command line thingy to do the profiling on a SnowLeopard
124 machine:
125
126 $ DOTEST_PROFILE=YES DOTEST_SCRIPT_DIR=/Volumes/data/lldb/svn/trunk/test /System/Library/Frameworks/Python.framework/Versions/Current/lib/python2.6/cProfile.py -o my.profile ./dotest.py -v -w 2> ~/Developer/Log/lldbtest.log
127
128 After that, I used the pstats.py module to browse the statistics:
129
130 $ python /System/Library/Frameworks/Python.framework/Versions/Current/lib/python2.6/pstats.py my.profile
131
132- Writing test cases:
133
134 We strongly prefer writing test cases using the SB API's rather than
135 the runCmd & expect. Unless you are actually testing some feature
136 of the command line, please don't write command based tests. For
137 historical reasons there are plenty of examples of tests in the test
138 suite that use runCmd where they shouldn't, but don't copy them,
139 copy the plenty that do use the SB API's instead.
140
141 The reason for this is that our policy is that we will maintain
142 compatibility with the SB API's. But we don't make any similar
143 guarantee about the details of command result format. If your test
144 is using the command line, it is going to have to check against the
145 command result text, and you either end up writing your check
146 pattern by checking as little as possible so you won't be exposed to
147 random changes in the text; in which case you can end up missing
148 some failure, or you test too much and it means irrelevant changes
149 break your tests.
150
151 However, if you use the Python API's it is possible to check all the
152 results you want to check in a very explicit way, which makes the
153 tests much more robust.
154
155 Even if you are testing that a command-line command does some
156 specific thing, it is still better in general to use the SB API's to
157 drive to the point where you want to run the test, then use
158 SBInterpreter::HandleCommand to run the command. You get the full
159 result text from the command in the command return object, and all
160 the part where you are driving the debugger to the point you want to
161 test will be more robust.
162
163 The sample_test directory contains a standard and an "inline" test
164 that are good starting points for writing a new test.
165
166- Attaching in test cases:
167
168 If you need to attach to inferiors in your tests, you must make sure
169 the inferior calls lldb_enable_attach(), before the debugger
170 attempts to attach. This function performs any platform-specific
171 processing needed to enable attaching to this process (e.g., on
172 Linux, we execute prctl(PR_SET_TRACER) syscall to disable
173 protections present in some Linux systems).
174