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.  The subclass should override the attribute 'mydir' in order for the
37  runtime to locate the individual test cases when running as part of a large
38  test suite or when running each test case as a separate Python invocation.
39
40  The doc string provides more details about the setup required for running a
41  test case on its own.  To run the whole test suite, 'dotest.py' is all you
42  need to do.
43
44- subdirectories of 'test'
45
46  Most of them predate the introduction of the python test suite and contain
47  example C/C++/ObjC source files which get compiled into executables which are
48  to be exercised by the debugger.
49
50  For such subdirectory which has an associated Test*.py file, it was added as
51  part of the Python-based test suite to test lldb functionality.
52
53  Some of the subdirectories, for example, the 'help' subdirectory, do not have
54  C/C++/ObjC source files; they were created to house the Python test case which
55  does not involve lldb reading in an executable file at all.
56
57  The sample_test directory contains examples of both a full and an "inline"
58  testcase that run a process to a breakpoint and check a local variable.  These
59  are convenient starting points for adding new tests.
60
61- make directory
62
63  Contains Makefile.rules, which can be utilized by test cases to write Makefile
64  based rules to build binaries for the inferiors.
65
66  By default, the built executable name is a.out, which can be overwritten by
67  specifying your EXE make variable, via the Makefile under the specific test
68  directory or via supplying a Python dictionary to the build method in your
69  Python test script.  An example of the latter can be found in
70  test/lang/objc/radar-9691614/TestObjCMethodReturningBOOL.py, where:
71
72    def test_method_ret_BOOL(self):
73        """Test that objective-c method returning BOOL works correctly."""
74        d = {'EXE': self.exe_name}
75        self.build(dictionary=d)
76        self.setTearDownCleanup(dictionary=d)
77        ...
78
79    def setUp(self):
80        # Call super's setUp().
81        TestBase.setUp(self)
82        # We'll use the test method name as the exe_name.
83        self.exe_name = self.testMethodName
84        # Find the line number to break inside main().
85        self.main_source = "main.m"
86        self.line = line_number(self.main_source, '// Set breakpoint here.')
87
88  The exe names for the two test methods are equal to the test method names and
89  are therefore guaranteed different.
90
91- plugins directory
92
93  Contains platform specific plugin to build binaries with dsym/dwarf debugging
94  info.  Other platform specific functionalities may be added in the future.
95
96- unittest2 directory
97
98  Many new features were added to unittest in Python 2.7, including test
99  discovery. unittest2 allows you to use these features with earlier versions of
100  Python.
101
102  It currently has unittest2 0.5.1 from http://pypi.python.org/pypi/unittest2.
103  Version 0.5.1 of unittest2 has feature parity with unittest in Python 2.7
104  final. If you want to ensure that your tests run identically under unittest2
105  and unittest in Python 2.7 you should use unittest2 0.5.1.
106
107  Later versions of unittest2 include changes in unittest made in Python 3.2 and
108  onwards after the release of Python 2.7.
109
110- dotest.pl
111
112  In case you wonder, there is also a 'dotest.pl' perl script file.  It was
113  created to visit each Python test case under the specified directory and
114  invoke Python's builtin unittest.main() on each test case.
115
116  It does not take advantage of the test runner and test suite functionality
117  provided by Python's unitest framework.  Its existence is because we want a
118  different way of running the whole test suite.  As lldb and the Python test
119  suite become more reliable, we don't expect to be using 'dotest.pl' anymore.
120
121  Note: dotest.pl has been moved to the attic directory.
122
123- Profiling dotest.py runs
124
125  I used the following command line thingy to do the profiling on a SnowLeopard
126  machine:
127
128    $ 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
129
130  After that, I used the pstats.py module to browse the statistics:
131
132    $ python /System/Library/Frameworks/Python.framework/Versions/Current/lib/python2.6/pstats.py my.profile
133
134- Writing test cases:
135
136  We strongly prefer writing test cases using the SB API's rather than
137  the runCmd & expect.  Unless you are actually testing some feature
138  of the command line, please don't write command based tests.  For
139  historical reasons there are plenty of examples of tests in the test
140  suite that use runCmd where they shouldn't, but don't copy them,
141  copy the plenty that do use the SB API's instead.
142
143  The reason for this is that our policy is that we will maintain
144  compatibility with the SB API's.  But we don't make any similar
145  guarantee about the details of command result format.  If your test
146  is using the command line, it is going to have to check against the
147  command result text, and you either end up writing your check
148  pattern by checking as little as possible so you won't be exposed to
149  random changes in the text; in which case you can end up missing
150  some failure, or you test too much and it means irrelevant changes
151  break your tests.
152
153  However, if you use the Python API's it is possible to check all the
154  results you want to check in a very explicit way, which makes the
155  tests much more robust.
156
157  Even if you are testing that a command-line command does some
158  specific thing, it is still better in general to use the SB API's to
159  drive to the point where you want to run the test, then use
160  SBInterpreter::HandleCommand to run the command.  You get the full
161  result text from the command in the command return object, and all
162  the part where you are driving the debugger to the point you want to
163  test will be more robust.
164
165  The sample_test directory contains a standard and an "inline" test
166  that are good starting points for writing a new test.
167
168- Attaching in test cases:
169
170  If you need to attach to inferiors in your tests, you must make sure
171  the inferior calls lldb_enable_attach(), before the debugger
172  attempts to attach. This function performs any platform-specific
173  processing needed to enable attaching to this process (e.g., on
174  Linux, we execute prctl(PR_SET_TRACER) syscall to disable
175  protections present in some Linux systems).
176