implement a test prototype for the LAMMPS shell

unittest/CMakeLists.txt

@@ -7,6 +7,7 @@ add_subdirectory(c-library)
 add_subdirectory(cplusplus)
 add_subdirectory(fortran)
 add_subdirectory(python)
+add_subdirectory(tools)
 add_subdirectory(force-styles)
 
 find_package(ClangFormat 8.0)

unittest/tools/CMakeLists.txt

@@ -0,0 +1,20 @@
+
+# we use python 3's subprocess module to run the tools and check the output
+if(CMAKE_VERSION VERSION_LESS 3.12)
+  find_package(PythonInterp 3.5) # Deprecated since version 3.12
+  if(PYTHONINTERP_FOUND)
+    set(Python_EXECUTABLE ${PYTHON_EXECUTABLE})
+  endif()
+else()
+  find_package(Python3 COMPONENTS Interpreter)
+endif()
+
+if(Python_EXECUTABLE)
+  if(BUILD_LAMMPS_SHELL)
+    add_test(NAME LammpsShell
+      COMMAND ${Python_EXECUTABLE} -u ${CMAKE_CURRENT_SOURCE_DIR}/test_lammps_shell.py -v
+      WORKING_DIRECTORY ${CMAKE_BINARY_DIR})
+  endif()
+else()
+  message(STATUS "Skipping Tests for LAMMPS tools: no suitable Python interpreter")
+endif()

unittest/tools/test_lammps_shell.py

@@ -0,0 +1,49 @@
+
+import os, re, subprocess, unittest
+
+# enable test mode
+os.putenv('LAMMPS_SHELL_TESTING','1')
+
+shell_prompt_re = r"(.*LAMMPS Shell> ([a-z0-9_]+) *([a-z0-9_\.]+)?.*)+"
+
+#
+class LammpsShell(unittest.TestCase):
+
+    def setUp(self):
+        self.proc = subprocess.Popen('./lammps-shell',
+                                     stdin=subprocess.PIPE, stdout=subprocess.PIPE)
+
+
+    def tearDown(self):
+        self.proc.kill()
+
+
+    def InputRunner(self,text):
+        """Test tab expansions"""
+        try:
+            [outs,errs] = self.proc.communicate(input=text, timeout=1)
+        except TimeoutExpired:
+            proc.kill()
+            [outs,errs] = proc.communicate()
+
+        #print(outs.decode())
+        return re.findall(shell_prompt_re, outs.decode('UTF-8'), re.MULTILINE)[0]
+
+    def testExpandClear(self):
+        """Test expansion of a shell specific command"""
+        self.assertEqual(self.InputRunner(b'cle\t\n')[1],"clear")
+
+    def testExpandSource(self):
+        """Test expansion of a shell command and a file name"""
+        with open('.tmp.in.source', 'w') as out:
+           print('units real', file=out)
+        out.close()
+        matches=self.InputRunner(b'sour\t.tmp.in.sou\t\n')
+        os.remove('.tmp.in.source')
+        self.assertEqual(matches[1],"source")
+        self.assertEqual(matches[2],".tmp.in.source")
+
+
+###########################
+if __name__ == "__main__":
+    unittest.main()