tests: add tests for warnings in build output

- add tests for build warnings and error messages
- simplify some code in build environment with plural() function

4 files changed, 85 insertions, 8 deletions

diff --git a/lib/spack/spack/build_environment.py b/lib/spack/spack/build_environment.py
index 6dde537e1d..92e86018bf 100644
--- a/lib/spack/spack/build_environment.py
+++ b/lib/spack/spack/build_environment.py
@@ -71,6 +71,7 @@ import spack.config
 import spack.main
 import spack.paths
 import spack.store
+from spack.util.string import plural
 from spack.environment import EnvironmentModifications, validate
 from spack.environment import preserve_environment
 from spack.util.environment import env_flag, filter_system_paths, get_path
@@ -914,17 +915,13 @@ class ChildError(InstallError):
                 nwar = len(warnings)
                 if nerr > 0:
                     # If errors are found, only display errors
-                    if nerr == 1:
-                        out.write("\n1 error found in build log:\n")
-                    else:
-                        out.write("\n%d errors found in build log:\n" % nerr)
+                    out.write(
+                        "\n%s found in build log:\n" % plural(nerr, 'error'))
                     out.write(make_log_context(errors))
                 elif nwar > 0:
                     # If no errors are found but warnings are, display warnings
-                    if nwar == 1:
-                        out.write("\n1 warning found in build log:\n")
-                    else:
-                        out.write("\n%d warnings found in build log:\n" % nwar)
+                    out.write(
+                        "\n%s found in build log:\n" % plural(nwar, 'warning'))
                     out.write(make_log_context(warnings))
 
         else:
diff --git a/lib/spack/spack/test/cmd/install.py b/lib/spack/spack/test/cmd/install.py
index 084eb59072..56049271c1 100644
--- a/lib/spack/spack/test/cmd/install.py
+++ b/lib/spack/spack/test/cmd/install.py
@@ -429,3 +429,30 @@ def test_cdash_upload_build_error(tmpdir, mock_fetch, install_mockery,
             assert report_file in report_dir.listdir()
             content = report_file.open().read()
             assert '<Text>configure: error: in /path/to/some/file:</Text>' in content
+
+
+@pytest.mark.disable_clean_stage_check
+def test_build_error_output(tmpdir, mock_fetch, install_mockery, capfd):
+    with capfd.disabled():
+        msg = ''
+        try:
+            install('build-error')
+            assert False, "no exception was raised!"
+        except spack.build_environment.ChildError as e:
+            msg = e.long_message
+
+        assert 'configure: error: in /path/to/some/file:' in msg
+        assert 'configure: error: cannot run C compiled programs.' in msg
+
+
+@pytest.mark.disable_clean_stage_check
+def test_build_warning_output(tmpdir, mock_fetch, install_mockery, capfd):
+    with capfd.disabled():
+        msg = ''
+        try:
+            install('build-warnings')
+        except spack.build_environment.ChildError as e:
+            msg = e.long_message
+
+        assert 'WARNING: ALL CAPITAL WARNING!' in msg
+        assert 'foo.c:89: warning: some weird warning!' in msg
diff --git a/lib/spack/spack/test/util/util_string.py b/lib/spack/spack/test/util/util_string.py
new file mode 100644
index 0000000000..48a6c60c45
--- /dev/null
+++ b/lib/spack/spack/test/util/util_string.py
@@ -0,0 +1,33 @@
+##############################################################################
+# Copyright (c) 2013-2018, Lawrence Livermore National Security, LLC.
+# Produced at the Lawrence Livermore National Laboratory.
+#
+# This file is part of Spack.
+# Created by Todd Gamblin, tgamblin@llnl.gov, All rights reserved.
+# LLNL-CODE-647188
+#
+# For details, see https://github.com/spack/spack
+# Please also see the NOTICE and LICENSE files for our notice and the LGPL.
+#
+# This program 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) version 2.1, February 1999.
+#
+# This program 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 terms and
+# conditions of 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, write to the Free Software
+# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+##############################################################################
+from spack.util.string import plural
+
+
+def test_plural():
+    assert plural(0, 'thing') == '0 things'
+    assert plural(1, 'thing') == '1 thing'
+    assert plural(2, 'thing') == '2 things'
+    assert plural(1, 'thing', 'wombats') == '1 thing'
+    assert plural(2, 'thing', 'wombats') == '2 wombats'
diff --git a/lib/spack/spack/util/string.py b/lib/spack/spack/util/string.py
index 3bab0c652e..a6a5342f1f 100644
--- a/lib/spack/spack/util/string.py
+++ b/lib/spack/spack/util/string.py
@@ -53,3 +53,23 @@ def comma_and(sequence):
 
 def quote(sequence, q="'"):
     return ['%s%s%s' % (q, e, q) for e in sequence]
+
+
+def plural(n, singular, plural=None):
+    """Pluralize <singular> word by adding an s if n != 1.
+
+    Arguments:
+        n (int): number of things there are
+        singular (str): singular form of word
+        plural (str, optional): optional plural form, for when it's not just
+            singular + 's'
+
+    Returns:
+        (str): "1 thing" if n == 1 or "n things" if n != 1
+    """
+    if n == 1:
+        return "%d %s" % (n, singular)
+    elif plural is not None:
+        return "%d %s" % (n, plural)
+    else:
+        return "%d %ss" % (n, singular)