Add compilation tests

Added a set of test inputs and expected outputs, for regression testing.

tests/test_samples.py

@@ -0,0 +1,61 @@
+# test_samples.py
+#
+# Copyright 2021 James Westman <james@jwestman.net>
+#
+# This file is free software; you can redistribute it and/or modify it
+# under the terms of the GNU Lesser General Public License as
+# published by the Free Software Foundation; either version 3 of the
+# License, or (at your option) any later version.
+#
+# This file is distributed in the hope that it will be useful, but
+# WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+# Lesser General Public License for more details.
+#
+# You should have received a copy of the GNU Lesser General Public
+# License along with this program.  If not, see <http://www.gnu.org/licenses/>.
+#
+# SPDX-License-Identifier: LGPL-3.0-or-later
+
+
+import difflib # I love Python
+from pathlib import Path
+import unittest
+
+from gtkblueprinttool import tokenizer, parser
+from gtkblueprinttool.errors import PrintableError
+from gtkblueprinttool.tokenizer import Token, TokenType, tokenize
+
+
+class TestSamples(unittest.TestCase):
+    def assert_sample(self, name):
+        with open((Path(__file__).parent / f"samples/{name}.blp").resolve()) as f:
+            blueprint = f.read()
+        with open((Path(__file__).parent / f"samples/{name}.ui").resolve()) as f:
+            expected = f.read()
+
+        tokens = tokenizer.tokenize(blueprint)
+        ast, errors = parser.parse(tokens)
+
+        if errors:
+            raise errors
+        if len(ast.errors):
+            raise MultipleErrors(ast.errors)
+
+        actual = ast.generate()
+        if actual.strip() != expected.strip():
+            diff = difflib.unified_diff(expected.splitlines(), actual.splitlines())
+            print("\n".join(diff))
+            raise AssertionError()
+
+
+    def test_samples(self):
+        self.assert_sample("binding")
+        self.assert_sample("child_type")
+        self.assert_sample("layout")
+        self.assert_sample("menu")
+        self.assert_sample("property")
+        self.assert_sample("signal")
+        self.assert_sample("style")
+        self.assert_sample("template")
+        self.assert_sample("using")