diff --git a/tests/cmdline/repl_lock.py b/tests/cmdline/repl_lock.py
new file mode 100644
index 0000000000..77e2e93274
--- /dev/null
+++ b/tests/cmdline/repl_lock.py
@@ -0,0 +1,7 @@
+import micropython
+micropython.heap_lock()
+1+1
+micropython.heap_lock()
+None # Cause the repl's line storage to be enlarged ----------------
+micropython.heap_lock()
+raise SystemExit
diff --git a/tests/cmdline/repl_lock.py.exp b/tests/cmdline/repl_lock.py.exp
new file mode 100644
index 0000000000..7cce24f6c6
--- /dev/null
+++ b/tests/cmdline/repl_lock.py.exp
@@ -0,0 +1,10 @@
+MicroPython \.\+ version
+Use \.\+
+>>> import micropython
+>>> micropython.heap_lock()
+>>> 1+1
+2
+>>> micropython.heap_lock()
+>>> None # Cause the repl's line storage to be enlarged ----------------
+>>> micropython.heap_lock()
+>>> raise SystemExit