Add test that runs all examples and makes sure they don't crash

7 files changed, 83 insertions, 13 deletions

diff --git a/examples/c_files/basic.c b/examples/c_files/basic.c
new file mode 100644
index 0000000..4cce7f6
--- /dev/null
+++ b/examples/c_files/basic.c
@@ -0,0 +1,3 @@
+int main() {
+  return 0;
+}
diff --git a/examples/dump_ast.py b/examples/dump_ast.py
index b7c3273..e82d038 100644
--- a/examples/dump_ast.py
+++ b/examples/dump_ast.py
@@ -18,7 +18,10 @@ from pycparser import parse_file
 
 if __name__ == "__main__":
     argparser = argparse.ArgumentParser('Dump AST')
-    argparser.add_argument('filename', help='name of file to parse')
+    argparser.add_argument('filename',
+                           default='examples/c_files/basic.c',
+                           nargs='?',
+                           help='name of file to parse')
     argparser.add_argument('--coord', help='show coordinates in the dump',
                            action='store_true')
     args = argparser.parse_args()
diff --git a/examples/func_defs_add_param.py b/examples/func_defs_add_param.py
index 9eb35c9..e9a89d1 100644
--- a/examples/func_defs_add_param.py
+++ b/examples/func_defs_add_param.py
@@ -9,6 +9,9 @@
 #-----------------------------------------------------------------
 from __future__ import print_function
 
+import sys
+sys.path.extend(['.', '..'])
+
 from pycparser import c_parser, c_ast, c_generator
 
 text = r"""
diff --git a/examples/rewrite_ast.py b/examples/rewrite_ast.py
index 164abb5..ea9adb3 100644
--- a/examples/rewrite_ast.py
+++ b/examples/rewrite_ast.py
@@ -7,7 +7,9 @@
 # License: BSD
 #-----------------------------------------------------------------
 from __future__ import print_function
+import sys
 
+sys.path.extend(['.', '..'])
 from pycparser import c_parser
 
 text = r"""
diff --git a/examples/serialize_ast.py b/examples/serialize_ast.py
index e0f8aa3..8669a0a 100644
--- a/examples/serialize_ast.py
+++ b/examples/serialize_ast.py
@@ -9,7 +9,9 @@
 #-----------------------------------------------------------------
 from __future__ import print_function
 import pickle
+import sys
 
+sys.path.extend(['.', '..'])
 from pycparser import c_parser
 
 text = r"""
@@ -19,18 +21,19 @@ void func(void)
 }
 """
 
-parser = c_parser.CParser()
-ast = parser.parse(text)
+if __name__ == '__main__':
+    parser = c_parser.CParser()
+    ast = parser.parse(text)
 
-# Since AST nodes use __slots__ for faster attribute access and
-# space saving, it needs Pickle's protocol version >= 2.
-# The default version is 3 for python 3.x and 1 for python 2.7.
-# You can always select the highest available protocol with the -1 argument.
+    # Since AST nodes use __slots__ for faster attribute access and
+    # space saving, it needs Pickle's protocol version >= 2.
+    # The default version is 3 for python 3.x and 1 for python 2.7.
+    # You can always select the highest available protocol with the -1 argument.
 
-with open('ast', 'wb') as f:
-    pickle.dump(ast, f, protocol=-1)
+    with open('ast', 'wb') as f:
+        pickle.dump(ast, f, protocol=-1)
 
-# Deserialize.
-with open('ast', 'rb') as f:
-    ast = pickle.load(f)
-    ast.show()
+    # Deserialize.
+    with open('ast', 'rb') as f:
+        ast = pickle.load(f)
+        ast.show()
diff --git a/tests/test_examples.py b/tests/test_examples.py
new file mode 100644
index 0000000..24cf16e
--- /dev/null
+++ b/tests/test_examples.py
@@ -0,0 +1,33 @@
+import os
+import sys
+import time
+import unittest
+
+sys.path.insert(0, '.')
+from tests.test_util import run_exe
+
+EMIT_ELAPSED_TIME = False
+
+# Runs all pycparser examples with no command-line arguments and makes sure they
+# run successfully (return code = 0), without actually verifying their output.
+class TestExamplesSucceed(unittest.TestCase):
+    def test_all_examples(self):
+        root = './examples'
+        for filename in os.listdir(root):
+            if os.path.splitext(filename)[1] == '.py':
+                # TODO: It would be nice to use subTest here, but that's not
+                # available in Python 2.7
+                # Use it when we finally drop Python 2...
+                path = os.path.join(root, filename)
+                t1 = time.time()
+                rc, stdout = run_exe(path)
+                elapsed = time.time() - t1
+                if EMIT_ELAPSED_TIME:
+                    print('{}... elapsed: {}'.format(filename, elapsed))
+                self.assertEqual(
+                    rc, 0, 'example "{}" failed with stdout =\n{}'.format(filename, stdout))
+
+
+if __name__ == '__main__':
+    EMIT_ELAPSED_TIME = True
+    unittest.main()
diff --git a/tests/test_util.py b/tests/test_util.py
index 3ac3886..435962d 100644
--- a/tests/test_util.py
+++ b/tests/test_util.py
@@ -7,7 +7,10 @@
 # This file contributed by vit9696@users.noreply.github.com
 # License: BSD
 #------------------------------------------------------------------------------
+import os
 import platform
+import subprocess
+import sys
 
 
 def cpp_supported():
@@ -29,3 +32,23 @@ def cpp_args(args=[]):
     if platform.system() == 'Darwin':
         return ['-E'] + args
     return args
+
+def _bytes2str(b):
+    if sys.version_info[0] == 3:
+        return b.decode('latin-1')
+    else:
+        return b
+
+def run_exe(exe_path, args=[], echo=False):
+    """ Runs the given executable as a subprocess, given the
+        list of arguments. Captures its return code (rc) and stdout and
+        returns a pair: rc, stdout_str
+    """
+    popen_cmd = [exe_path] + args
+    if os.path.splitext(exe_path)[1] == '.py':
+        popen_cmd.insert(0, sys.executable)
+    if echo:
+      print('[cmd]', ' '.join(popen_cmd))
+    proc = subprocess.Popen(popen_cmd, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
+    proc_stdout = proc.communicate()[0]
+    return proc.returncode, _bytes2str(proc_stdout)