Add bindep.txt as default filename

We use bindep.txt as default file and for compatibility handle
other-requirements.txt as well.
* If both files exist, bindep will fail.
* If neither of the files exist, bindep will fail.
* If a command line arg is given, it will be the only file looked at.

Adjust testsuite for change.

Change-Id: If9aaf24b1c7f489d8c7388707afc3316ca6f84f0

NEWS.rst

@@ -1,3 +1,10 @@
+Change of default file
+======================
+
+File bindep.txt is now the default bindep file. For compatibility with
+previous releases, bindep will check other-requirements.txt if
+bindep.txt does not exist.
+
 Backward-Incompatible Changes Between 1.0.0 and 2.0.0
 =====================================================
 

README.rst

@@ -11,13 +11,16 @@ installed before `pip` can be used - such as `virtualenv` and `pip` itself.
 Basics
 ======
 
-Create a file called ``other-requirements.txt`` and in that list any
+Create a file called ``bindep.txt`` and in that list any
 requirements your application / library has. In your README or INSTALL or
 other documentation you can tell users to run `bindep` to report on missing
 dependencies. Users without `bindep` installed can consult the
-``other-requirements.txt`` file by hand if they choose, or install `bindep`
+``bindep.txt`` file by hand if they choose, or install `bindep`
 first and then use it.
 
+If no ``bindep.txt`` file exists, `bindep` will look at the
+old location ``other-requirements.txt``.
+
 The output from bindep is fairly verbose normally, but passing an option of
 -b/--brief outputs just the missing packages one per line, suitable for feeding
 to your package management tool of choice.

bindep/main.py

@@ -17,6 +17,7 @@
 
 import logging
 import optparse
+import os.path
 import sys
 
 import bindep.depends
@@ -35,8 +36,9 @@ def main(depends=None):
         help="List only missing packages one per line.")
     parser.add_option(
         "-f", "--file", action="store", type="string", dest="filename",
-        default="other-requirements.txt",
-        help="Package list file (default: other-requirements.txt).")
+        default="",
+        help="Package list file (default: bindep.txt or "
+             "other-requirements.txt).")
     parser.add_option(
         "--profiles", action="store_true",
         help="List the platform and configuration profiles.")
@@ -44,12 +46,35 @@ def main(depends=None):
     if depends is None:
         if opts.filename == "-":
             fd = sys.stdin
-        else:
+        elif opts.filename:
             try:
                 fd = open(opts.filename, 'rt')
             except IOError:
-                logging.error('No %s file found.' % opts.filename)
+                logging.error('Error reading file %s.' % opts.filename)
                 return 1
+        else:
+            if (os.path.isfile('bindep.txt') and
+                os.path.isfile('other-requirements.txt')):
+                logging.error('Both bindep.txt and other-requirements.txt '
+                              'files exist, choose one.')
+                return 1
+            if os.path.isfile('bindep.txt'):
+                try:
+                    fd = open('bindep.txt', 'rt')
+                except IOError:
+                    logging.error('Error reading file bindep.txt.')
+                    return 1
+            elif os.path.isfile('other-requirements.txt'):
+                try:
+                    fd = open('other-requirements.txt', 'rt')
+                except IOError:
+                    logging.error('Error reading file other-requirements.txt.')
+                    return 1
+            else:
+                logging.error('Neither file bindep.txt nor file '
+                              'other-requirements.txt exist.')
+                return 1
+
         depends = bindep.depends.Depends(fd.read())
     if opts.profiles:
         logging.info("Platform profiles:")

bindep/tests/test_main.py

@@ -71,7 +71,8 @@ class TestMain(TestCase):
         self.useFixture(MonkeyPatch('sys.argv', ['bindep']))
         self.assertEqual(1, main())
         self.assertEqual(
-            'No other-requirements.txt file found.\n', fixture.logger.output)
+            'Neither file bindep.txt nor file other-requirements.txt exist.\n',
+            fixture.logger.output)
 
     def test_empty_requirements_file(self):
         fixture = self.useFixture(MainFixture())
@@ -96,7 +97,7 @@ class TestMain(TestCase):
             'bindep', '--file', 'alternative-requirements.txt']))
         self.assertEqual(1, main())
         self.assertEqual(
-            'No alternative-requirements.txt file found.\n',
+            'Error reading file alternative-requirements.txt.\n',
             fixture.logger.output)
 
     def test_stdin_requirements_file(self):