diff --git a/lldb/source/Interpreter/embedded_interpreter.py b/lldb/source/Interpreter/embedded_interpreter.py
--- a/lldb/source/Interpreter/embedded_interpreter.py
+++ b/lldb/source/Interpreter/embedded_interpreter.py
@@ -116,6 +116,10 @@
         input_string = strip_and_check_exit(input_string)
         repl = code.InteractiveConsole(local_dict)
         if input_string:
+            # A newline is appended to support one-line statements containing
+            # control flow. For example "if True: print(1)" silently does
+            # nothing, but works with a newline: "if True: print(1)\n".
+            input_string += "\n"
             repl.runsource(input_string)
         elif g_run_one_line_str:
             repl.runsource(g_run_one_line_str)
diff --git a/lldb/test/Shell/ScriptInterpreter/Python/python.test b/lldb/test/Shell/ScriptInterpreter/Python/python.test
--- a/lldb/test/Shell/ScriptInterpreter/Python/python.test
+++ b/lldb/test/Shell/ScriptInterpreter/Python/python.test
@@ -5,6 +5,7 @@
 # RUN: %lldb -o 'script -lpython -- print("{}".format(1000+100+10+1))' 2>&1 | FileCheck %s
 # RUN: %lldb -o 'script --language python -- print("{}".format(1000+100+10+1))' 2>&1 | FileCheck %s
 # RUN: %lldb -o 'script --language=python -- print("{}".format(1000+100+10+1))' 2>&1 | FileCheck %s
+# RUN: %lldb -o 'script -lpython -- if True: print("{}".format(1000+100+10+1))' 2>&1 | FileCheck %s
 # CHECK: 1111
 
 # RUN: %lldb -o 'script --language invalid -- print("{}".format(1000+100+10+1))' 2>&1 | FileCheck %s --check-prefix INVALID