3 files changed, 116 insertions, 0 deletions
diff --git a/packages/Python/lldbsuite/test/functionalities/thread/num_threads/Makefile b/packages/Python/lldbsuite/test/functionalities/thread/num_threads/Makefile
new file mode 100644
index 000000000000..67aa16625bff
--- /dev/null
+++ b/packages/Python/lldbsuite/test/functionalities/thread/num_threads/Makefile
@@ -0,0 +1,5 @@
+LEVEL = ../../../make
+
+CXX_SOURCES := main.cpp
+ENABLE_THREADS := YES
+include $(LEVEL)/Makefile.rules
diff --git a/packages/Python/lldbsuite/test/functionalities/thread/num_threads/TestNumThreads.py b/packages/Python/lldbsuite/test/functionalities/thread/num_threads/TestNumThreads.py
new file mode 100644
index 000000000000..094c86705969
--- /dev/null
+++ b/packages/Python/lldbsuite/test/functionalities/thread/num_threads/TestNumThreads.py
@@ -0,0 +1,61 @@
+"""
+Test number of threads.
+"""
+
+from __future__ import print_function
+
+
+import os
+import time
+import lldb
+from lldbsuite.test.lldbtest import *
+import lldbsuite.test.lldbutil as lldbutil
+
+
+class NumberOfThreadsTestCase(TestBase):
+
+    mydir = TestBase.compute_mydir(__file__)
+
+    def setUp(self):
+        # Call super's setUp().
+        TestBase.setUp(self)
+        # Find the line number to break inside main().
+        self.line = line_number('main.cpp', '// Set break point at this line.')
+
+    def test(self):
+        """Test number of threads."""
+        self.build()
+        exe = os.path.join(os.getcwd(), "a.out")
+        self.runCmd("file " + exe, CURRENT_EXECUTABLE_SET)
+
+        # This should create a breakpoint with 1 location.
+        lldbutil.run_break_set_by_file_and_line(
+            self, "main.cpp", self.line, num_expected_locations=1)
+
+        # The breakpoint list should show 3 locations.
+        self.expect(
+            "breakpoint list -f",
+            "Breakpoint location shown correctly",
+            substrs=[
+                "1: file = 'main.cpp', line = %d, exact_match = 0, locations = 1" %
+                self.line])
+
+        # Run the program.
+        self.runCmd("run", RUN_SUCCEEDED)
+
+        # Stopped once.
+        self.expect("thread list", STOPPED_DUE_TO_BREAKPOINT,
+                    substrs=["stop reason = breakpoint 1."])
+
+        # Get the target process
+        target = self.dbg.GetSelectedTarget()
+        process = target.GetProcess()
+
+        # Get the number of threads
+        num_threads = process.GetNumThreads()
+
+        # Using std::thread may involve extra threads, so we assert that there are
+        # at least 4 rather than exactly 4.
+        self.assertTrue(
+            num_threads >= 4,
+            'Number of expected threads and actual threads do not match.')
diff --git a/packages/Python/lldbsuite/test/functionalities/thread/num_threads/main.cpp b/packages/Python/lldbsuite/test/functionalities/thread/num_threads/main.cpp
new file mode 100644
index 000000000000..6a0ea4e0d119
--- /dev/null
+++ b/packages/Python/lldbsuite/test/functionalities/thread/num_threads/main.cpp
@@ -0,0 +1,50 @@
+#include <condition_variable>
+#include <mutex>
+#include <thread>
+
+std::mutex mutex;
+std::condition_variable cond;
+
+void *
+thread3(void *input)
+{
+    std::unique_lock<std::mutex> lock(mutex);
+    cond.notify_all(); // Set break point at this line.
+    return NULL;
+}
+
+void *
+thread2(void *input)
+{
+    std::unique_lock<std::mutex> lock(mutex);
+    cond.notify_all();
+    cond.wait(lock);
+    return NULL;
+}
+
+void *
+thread1(void *input)
+{
+    std::thread thread_2(thread2, nullptr);
+    thread_2.join();
+
+    return NULL;
+}
+
+int main()
+{
+    std::unique_lock<std::mutex> lock(mutex);
+
+    std::thread thread_1(thread1, nullptr);
+    cond.wait(lock);
+
+    std::thread thread_3(thread3, nullptr);
+    cond.wait(lock);
+
+    lock.unlock();
+
+    thread_1.join();
+    thread_3.join();
+
+    return 0;
+}