Add tests.

test/usecases/CMakeLists.txt

@@ -25,6 +25,7 @@ set(NMODL_USECASE_DIRS
     point_process
     pointer
     procedure
+    protect
     random
     solve
     state

test/usecases/protect/shared_counter.mod

@@ -0,0 +1,17 @@
+NEURON {
+    SUFFIX shared_counter
+    GLOBAL g_cnt
+}
+
+ASSIGNED {
+    g_cnt
+}
+
+
+INITIAL {
+    PROTECT g_cnt = 0
+}
+
+BREAKPOINT {
+    PROTECT g_cnt = g_cnt + 1
+}

test/usecases/protect/test_shared_counter.py

@@ -0,0 +1,30 @@
+from neuron import h, gui
+
+
+def test_shared_counter():
+    nthreads = 32
+    nseg = 10
+    nsteps = 100
+
+    sections = [h.Section() for _ in range(nthreads)]
+    for s in sections:
+        s.insert("shared_counter")
+        s.nseg = nseg
+
+    pc = h.ParallelContext()
+
+    pc.nthread(nthreads)
+    for k, s in enumerate(sections):
+        pc.partition(k, h.SectionList([s]))
+
+    h.finitialize()
+    for _ in range(nsteps):
+        h.step()
+
+    expected = nthreads * nseg * nsteps
+    g_cnt = h.g_cnt_shared_counter
+    assert h.g_cnt_shared_counter == expected, f"{g_cnt}"
+
+
+if __name__ == "__main__":
+    test_shared_counter()