1 files changed, 75 insertions, 0 deletions
diff --git a/packages/Python/lldbsuite/test/functionalities/data-formatter/synthcapping/TestSyntheticCapping.py b/packages/Python/lldbsuite/test/functionalities/data-formatter/synthcapping/TestSyntheticCapping.py
new file mode 100644
index 000000000000..0550f57ae62a
--- /dev/null
+++ b/packages/Python/lldbsuite/test/functionalities/data-formatter/synthcapping/TestSyntheticCapping.py
@@ -0,0 +1,75 @@
+"""
+Check for an issue where capping does not work because the Target pointer appears to be changing behind our backs
+"""
+
+from __future__ import print_function
+
+
+
+import os, time
+import lldb
+from lldbsuite.test.lldbtest import *
+import lldbsuite.test.lldbutil as lldbutil
+
+class SyntheticCappingTestCase(TestBase):
+
+    mydir = TestBase.compute_mydir(__file__)
+
+    def setUp(self):
+        # Call super's setUp().
+        TestBase.setUp(self)
+        # Find the line number to break at.
+        self.line = line_number('main.cpp', '// Set break point at this line.')
+
+    def test_with_run_command(self):
+        """Check for an issue where capping does not work because the Target pointer appears to be changing behind our backs."""
+        self.build()
+        self.runCmd("file a.out", CURRENT_EXECUTABLE_SET)
+
+        lldbutil.run_break_set_by_file_and_line (self, "main.cpp", self.line, num_expected_locations=1, loc_exact=True)
+
+        self.runCmd("run", RUN_SUCCEEDED)
+
+        # The stop reason of the thread should be breakpoint.
+        self.expect("thread list", STOPPED_DUE_TO_BREAKPOINT,
+            substrs = ['stopped',
+                       'stop reason = breakpoint'])
+
+        # This is the function to remove the custom formats in order to have a
+        # clean slate for the next test case.
+        def cleanup():
+            self.runCmd('type format clear', check=False)
+            self.runCmd('type summary clear', check=False)
+            self.runCmd('type filter clear', check=False)
+            self.runCmd('type synth clear', check=False)
+            self.runCmd("settings set target.max-children-count 256", check=False)
+
+        # Execute the cleanup function during test case tear down.
+        self.addTearDownHook(cleanup)
+
+        # set up the synthetic children provider
+        self.runCmd("script from fooSynthProvider import *")
+        self.runCmd("type synth add -l fooSynthProvider foo")
+
+        # check that the synthetic children work, so we know we are doing the right thing
+        self.expect("frame variable f00_1",
+                    substrs = ['r = 33',
+                               'fake_a = 16777216',
+                               'a = 0']);
+
+        # check that capping works
+        self.runCmd("settings set target.max-children-count 2", check=False)
+        
+        self.expect("frame variable f00_1",
+                    substrs = ['...',
+                               'fake_a = 16777216',
+                               'a = 0']);
+        
+        self.expect("frame variable f00_1", matching=False,
+                    substrs = ['r = 33']);
+
+        
+        self.runCmd("settings set target.max-children-count 256", check=False)
+
+        self.expect("frame variable f00_1", matching=True,
+                    substrs = ['r = 33']);