1 files changed, 133 insertions, 0 deletions
diff --git a/packages/Python/lldbsuite/test/python_api/value/linked_list/TestValueAPILinkedList.py b/packages/Python/lldbsuite/test/python_api/value/linked_list/TestValueAPILinkedList.py
new file mode 100644
index 000000000000..22d7e7ebf7e8
--- /dev/null
+++ b/packages/Python/lldbsuite/test/python_api/value/linked_list/TestValueAPILinkedList.py
@@ -0,0 +1,133 @@
+"""
+Test SBValue API linked_list_iter which treats the SBValue as a linked list and
+supports iteration till the end of list is reached.
+"""
+
+from __future__ import print_function
+
+
+
+import os, time
+import re
+import lldb
+import lldbsuite.test.lldbutil as lldbutil
+from lldbsuite.test.lldbtest import *
+
+class ValueAsLinkedListTestCase(TestBase):
+
+    mydir = TestBase.compute_mydir(__file__)
+
+    def setUp(self):
+        # Call super's setUp().
+        TestBase.setUp(self)
+        # We'll use the test method name as the exe_name.
+        self.exe_name = self.testMethodName
+        # Find the line number to break at.
+        self.line = line_number('main.cpp', '// Break at this line')
+
+    @add_test_categories(['pyapi'])
+    def test(self):
+        """Exercise SBValue API linked_list_iter."""
+        d = {'EXE': self.exe_name}
+        self.build(dictionary=d)
+        self.setTearDownCleanup(dictionary=d)
+        exe = os.path.join(os.getcwd(), self.exe_name)
+
+        # Create a target by the debugger.
+        target = self.dbg.CreateTarget(exe)
+        self.assertTrue(target, VALID_TARGET)
+
+        # Create the breakpoint inside function 'main'.
+        breakpoint = target.BreakpointCreateByLocation('main.cpp', self.line)
+        self.assertTrue(breakpoint, 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)
+
+        # Get Frame #0.
+        self.assertTrue(process.GetState() == lldb.eStateStopped)
+        thread = lldbutil.get_stopped_thread(process, lldb.eStopReasonBreakpoint)
+        self.assertTrue(thread.IsValid(), "There should be a thread stopped due to breakpoint condition")
+        frame0 = thread.GetFrameAtIndex(0)
+
+        # Get variable 'task_head'.
+        task_head = frame0.FindVariable('task_head')
+        self.assertTrue(task_head, VALID_VARIABLE)
+        self.DebugSBValue(task_head)
+
+        # By design (see main.cpp), the visited id's are: [1, 2, 4, 5].
+        visitedIDs = [1, 2, 4, 5]
+        list = []
+
+        cvf = lldbutil.ChildVisitingFormatter(indent_child=2)
+        for t in task_head.linked_list_iter('next'):
+            self.assertTrue(t, VALID_VARIABLE)
+            # Make sure that 'next' corresponds to an SBValue with pointer type.
+            self.assertTrue(t.TypeIsPointerType())
+            if self.TraceOn():
+                print(cvf.format(t))
+            list.append(int(t.GetChildMemberWithName("id").GetValue()))
+
+        # Sanity checks that the we visited all the items (no more, no less).
+        if self.TraceOn():
+            print("visited IDs:", list)
+        self.assertTrue(visitedIDs == list)
+
+        # Let's exercise the linked_list_iter() API again, this time supplying
+        # our end of list test function.
+        def eol(val):
+            """Test function to determine end of list."""
+            # End of list is reached if either the value object is invalid
+            # or it corresponds to a null pointer.
+            if not val or int(val.GetValue(), 16) == 0:
+                return True
+            # Also check the "id" for correct semantics.  If id <= 0, the item
+            # is corrupted, let's return True to signify end of list.
+            if int(val.GetChildMemberWithName("id").GetValue(), 0) <= 0:
+                return True
+
+            # Otherwise, return False.
+            return False
+
+        list = []
+        for t in task_head.linked_list_iter('next', eol):
+            self.assertTrue(t, VALID_VARIABLE)
+            # Make sure that 'next' corresponds to an SBValue with pointer type.
+            self.assertTrue(t.TypeIsPointerType())
+            if self.TraceOn():
+                print(cvf.format(t))
+            list.append(int(t.GetChildMemberWithName("id").GetValue()))
+
+        # Sanity checks that the we visited all the items (no more, no less).
+        if self.TraceOn():
+            print("visited IDs:", list)
+        self.assertTrue(visitedIDs == list)
+        
+        # Get variable 'empty_task_head'.
+        empty_task_head = frame0.FindVariable('empty_task_head')
+        self.assertTrue(empty_task_head, VALID_VARIABLE)
+        self.DebugSBValue(empty_task_head)
+
+        list = []
+        # There is no iterable item from empty_task_head.linked_list_iter().
+        for t in empty_task_head.linked_list_iter('next', eol):
+            if self.TraceOn():
+                print(cvf.format(t))
+            list.append(int(t.GetChildMemberWithName("id").GetValue()))
+
+        self.assertTrue(len(list) == 0)
+
+        # Get variable 'task_evil'.
+        task_evil = frame0.FindVariable('task_evil')
+        self.assertTrue(task_evil, VALID_VARIABLE)
+        self.DebugSBValue(task_evil)
+
+        list = []
+        # There 3 iterable items from task_evil.linked_list_iter(). :-)
+        for t in task_evil.linked_list_iter('next'):
+            if self.TraceOn():
+                print(cvf.format(t))
+            list.append(int(t.GetChildMemberWithName("id").GetValue()))
+
+        self.assertTrue(len(list) == 3)