Run Python unittests and doctests.

Add a meta/check.sh script that runs unit tests before the syntax
linters.

Add unittest converters for the existing doctests.

meta/check.sh

@@ -1,8 +1,12 @@
 #!/bin/bash
+set -e
+cd $(dirname "$0")
+
+# Run unit tests.
+python -m unittest discover
 
 # Check Python sources for Python 3 compatibility using pylint.
 #
 # Install pylint with 'pip install pylint'.
-cd $(dirname "$0")
 pylint --py3k --reports=no -- *.py cretonne isa
 flake8 .

meta/constant_hash.py

@@ -74,7 +74,3 @@ def compute_quadratic(items, hash_function):
         table[h] = i
 
     return table
-
-if __name__ == "__main__":
-    import doctest
-    doctest.testmod()

meta/srcgen.py

@@ -121,7 +121,3 @@ class Formatter(object):
         """Add a (multi-line) documentation comment."""
         s = re.sub('^', self.indent + '/// ', s, flags=re.M) + '\n'
         self.lines.append(s)
-
-if __name__ == "__main__":
-    import doctest
-    doctest.testmod()

meta/test_constant_hash.py

@@ -0,0 +1,8 @@
+from __future__ import absolute_import
+import doctest
+import constant_hash
+
+
+def load_tests(loader, tests, ignore):
+    tests.addTests(doctest.DocTestSuite(constant_hash))
+    return tests

meta/test_srcgen.py

@@ -0,0 +1,8 @@
+from __future__ import absolute_import
+import doctest
+import srcgen
+
+
+def load_tests(loader, tests, ignore):
+    tests.addTests(doctest.DocTestSuite(srcgen))
+    return tests