[scan-build-py] move function report_directory from report module to analyze module

Differential Revision: https://reviews.llvm.org/D29255

llvm-svn: 295045
diff --git a/clang/tools/scan-build-py/tests/unit/test_analyze.py b/clang/tools/scan-build-py/tests/unit/test_analyze.py
index 481cc0c..5cfc121 100644
--- a/clang/tools/scan-build-py/tests/unit/test_analyze.py
+++ b/clang/tools/scan-build-py/tests/unit/test_analyze.py
@@ -4,4 +4,19 @@
 # This file is distributed under the University of Illinois Open Source
 # License. See LICENSE.TXT for details.
 
+import libear
 import libscanbuild.analyze as sut
+import unittest
+
+class ReportDirectoryTest(unittest.TestCase):
+
+    # Test that successive report directory names ascend in lexicographic
+    # order. This is required so that report directories from two runs of
+    # scan-build can be easily matched up to compare results.
+    def test_directory_name_comparison(self):
+        with libear.TemporaryDirectory() as tmpdir, \
+             sut.report_directory(tmpdir, False) as report_dir1, \
+             sut.report_directory(tmpdir, False) as report_dir2, \
+             sut.report_directory(tmpdir, False) as report_dir3:
+            self.assertLess(report_dir1, report_dir2)
+            self.assertLess(report_dir2, report_dir3)