TestObjCStepping.py   [plain text]

"""Test stepping through ObjC method dispatch in various forms."""

import os, time
import unittest2
import lldb
import lldbutil
from lldbtest import *

class TestObjCStepping(TestBase):

    def getCategories (self):
        return ['basic_process']

    mydir = TestBase.compute_mydir(__file__)

    @unittest2.skipUnless(sys.platform.startswith("darwin"), "requires Darwin")
    @python_api_test
    @dsym_test
    def test_with_dsym_and_python_api(self):
        """Test stepping through ObjC method dispatch in various forms."""
        self.buildDsym()
        self.objc_stepping()

    @unittest2.skipUnless(sys.platform.startswith("darwin"), "requires Darwin")
    @python_api_test
    @dwarf_test
    def test_with_dwarf_and_python_api(self):
        """Test stepping through ObjC method dispatch in various forms."""
        self.buildDwarf()
        self.objc_stepping()

    def setUp(self):
        # Call super's setUp().
        TestBase.setUp(self)
        # Find the line numbers that we will step to in main:
        self.main_source = "stepping-tests.m"
        self.source_randomMethod_line = line_number (self.main_source, '// Source randomMethod start line.')
        self.sourceBase_randomMethod_line = line_number (self.main_source, '// SourceBase randomMethod start line.')
        self.source_returnsStruct_start_line = line_number (self.main_source, '// Source returnsStruct start line.')
        self.sourceBase_returnsStruct_start_line = line_number (self.main_source, '// SourceBase returnsStruct start line.')
        self.stepped_past_nil_line = line_number (self.main_source, '// Step over nil should stop here.')

    def objc_stepping(self):
        """Use Python APIs to test stepping into ObjC methods."""
        exe = os.path.join(os.getcwd(), "a.out")

        target = self.dbg.CreateTarget(exe)
        self.assertTrue(target, VALID_TARGET)

        self.main_source_spec = lldb.SBFileSpec (self.main_source)

        breakpoints_to_disable = []

        break1 = target.BreakpointCreateBySourceRegex ("// Set first breakpoint here.", self.main_source_spec)
        self.assertTrue(break1, VALID_BREAKPOINT)
        breakpoints_to_disable.append (break1)

        break2 = target.BreakpointCreateBySourceRegex ("// Set second breakpoint here.", self.main_source_spec)
        self.assertTrue(break2, VALID_BREAKPOINT)
        breakpoints_to_disable.append (break2)

        break3 = target.BreakpointCreateBySourceRegex ('// Set third breakpoint here.', self.main_source_spec)
        self.assertTrue(break3, VALID_BREAKPOINT)
        breakpoints_to_disable.append (break3)

        break4 = target.BreakpointCreateBySourceRegex ('// Set fourth breakpoint here.', self.main_source_spec)
        self.assertTrue(break4, VALID_BREAKPOINT)
        breakpoints_to_disable.append (break4)

        break5 = target.BreakpointCreateBySourceRegex ('// Set fifth breakpoint here.', self.main_source_spec)
        self.assertTrue(break5, VALID_BREAKPOINT)
        breakpoints_to_disable.append (break5)

        break_returnStruct_call_super = target.BreakpointCreateBySourceRegex ('// Source returnsStruct call line.', self.main_source_spec)
        self.assertTrue(break_returnStruct_call_super, VALID_BREAKPOINT)
        breakpoints_to_disable.append (break_returnStruct_call_super)

        break_step_nil = target.BreakpointCreateBySourceRegex ('// Set nil step breakpoint here.', self.main_source_spec)
        self.assertTrue(break_step_nil, VALID_BREAKPOINT)

        # Now launch the process, and do not stop at entry point.
        process = target.LaunchSimple (None, None, self.get_process_working_directory())

        self.assertTrue(process, PROCESS_IS_VALID)

        # The stop reason of the thread should be breakpoint.
        threads = lldbutil.get_threads_stopped_at_breakpoint (process, break1)
        if len(threads) != 1:
            self.fail ("Failed to stop at breakpoint 1.")

        thread = threads[0]

        mySource = thread.GetFrameAtIndex(0).FindVariable("mySource")
        self.assertTrue(mySource, "Found mySource local variable.")
        mySource_isa = mySource.GetChildMemberWithName ("isa")
        self.assertTrue(mySource_isa, "Found mySource->isa local variable.")
        className = mySource_isa.GetSummary ()

        if self.TraceOn():
             print mySource_isa

        # Lets delete mySource so we can check that after stepping a child variable
        # with no parent persists and is useful.
        del (mySource)

        # Now step in, that should leave us in the Source randomMethod:
        thread.StepInto()
        line_number = thread.GetFrameAtIndex(0).GetLineEntry().GetLine()
        self.assertTrue (line_number == self.source_randomMethod_line, "Stepped into Source randomMethod.")

        # Now step in again, through the super call, and that should leave us in the SourceBase randomMethod:
        thread.StepInto()
        line_number = thread.GetFrameAtIndex(0).GetLineEntry().GetLine()
        self.assertTrue (line_number == self.sourceBase_randomMethod_line, "Stepped through super into SourceBase randomMethod.")

        threads = lldbutil.continue_to_breakpoint (process, break2)
        self.assertTrue (len(threads) == 1, "Continued to second breakpoint in main.")

        # Again, step in twice gets us to a stret method and a stret super call:
        thread = threads[0]
        thread.StepInto()
        line_number = thread.GetFrameAtIndex(0).GetLineEntry().GetLine()
        self.assertTrue (line_number == self.source_returnsStruct_start_line, "Stepped into Source returnsStruct.")

        threads = lldbutil.continue_to_breakpoint (process, break_returnStruct_call_super)
        self.assertTrue (len(threads) == 1, "Stepped to the call super line in Source returnsStruct.")
        thread = threads[0]

        thread.StepInto()
        line_number = thread.GetFrameAtIndex(0).GetLineEntry().GetLine()
        self.assertTrue (line_number == self.sourceBase_returnsStruct_start_line, "Stepped through super into SourceBase returnsStruct.")

        # Cool now continue to get past the call that intializes the Observer, and then do our steps in again to see that 
        # we can find our way when we're stepping through a KVO swizzled object.

        threads = lldbutil.continue_to_breakpoint (process, break3)
        self.assertTrue (len(threads) == 1, "Continued to third breakpoint in main, our object should now be swizzled.")

        newClassName = mySource_isa.GetSummary ()

        if self.TraceOn():
             print mySource_isa

        self.assertTrue (newClassName != className, "The isa did indeed change, swizzled!")

        # Now step in, that should leave us in the Source randomMethod:
        thread = threads[0]
        thread.StepInto()
        line_number = thread.GetFrameAtIndex(0).GetLineEntry().GetLine()
        self.assertTrue (line_number == self.source_randomMethod_line, "Stepped into Source randomMethod in swizzled object.")

        # Now step in again, through the super call, and that should leave us in the SourceBase randomMethod:
        thread.StepInto()
        line_number = thread.GetFrameAtIndex(0).GetLineEntry().GetLine()
        self.assertTrue (line_number == self.sourceBase_randomMethod_line, "Stepped through super into SourceBase randomMethod in swizzled object.")

        threads = lldbutil.continue_to_breakpoint (process, break4)
        self.assertTrue (len(threads) == 1, "Continued to fourth breakpoint in main.")
        thread = threads[0]

        # Again, step in twice gets us to a stret method and a stret super call:
        thread.StepInto()
        line_number = thread.GetFrameAtIndex(0).GetLineEntry().GetLine()
        self.assertTrue (line_number == self.source_returnsStruct_start_line, "Stepped into Source returnsStruct in swizzled object.")

        threads = lldbutil.continue_to_breakpoint(process, break_returnStruct_call_super)
        self.assertTrue (len(threads) == 1, "Stepped to the call super line in Source returnsStruct - second time.")
        thread = threads[0]

        thread.StepInto()
        line_number = thread.GetFrameAtIndex(0).GetLineEntry().GetLine()
        self.assertTrue (line_number == self.sourceBase_returnsStruct_start_line, "Stepped through super into SourceBase returnsStruct in swizzled object.")

        for bkpt in breakpoints_to_disable:
            bkpt.SetEnabled(False)

        threads = lldbutil.continue_to_breakpoint (process, break_step_nil)
        self.assertTrue (len(threads) == 1, "Continued to step nil breakpoint.")

        thread.StepInto()
        line_number = thread.GetFrameAtIndex(0).GetLineEntry().GetLine()
        self.assertTrue (line_number == self.stepped_past_nil_line, "Step in over dispatch to nil stepped over.")

if __name__ == '__main__':
    import atexit
    lldb.SBDebugger.Initialize()
    atexit.register(lambda: lldb.SBDebugger.Terminate())
    unittest2.main()