Use print function rather than print statement

This is for Python 3 compatibility, since Python 3 does not support
the print statement, only the print function.  (Python 2.6 and 2.7
support both, depending on whether a __future__ import is used.)

Paths containing "xen" were left alone, because of comments in a
couple of the files indicating that the XenServer code needed to be
compatible with Python 2.4.

Fixes bug 1226943

Change-Id: I23b804a4d99500b4acf81dd19645ab06dfcc9f1c

5 files changed, 40 insertions, 28 deletions

diff --git a/tools/config/analyze_opts.py b/tools/config/analyze_opts.py
index 84294c9d31..c91f4dedaf 100755
--- a/tools/config/analyze_opts.py
+++ b/tools/config/analyze_opts.py
@@ -21,6 +21,9 @@ find_unused_options.py
 Compare the nova.conf file with the nova.conf.sample file to find any unused
 options or default values in nova.conf
 '''
+
+from __future__ import print_function
+
 import argparse
 import os
 import sys
@@ -74,7 +77,7 @@ if __name__ == '__main__':
 
     for k, v in sorted(conf_file_options.items()):
         if k not in sample_conf_file_options:
-            print "Unused:", k
+            print("Unused:", k)
     for k, v in sorted(conf_file_options.items()):
         if k in sample_conf_file_options and v == sample_conf_file_options[k]:
-            print "Default valued:", k
+            print("Default valued:", k)
diff --git a/tools/db/schema_diff.py b/tools/db/schema_diff.py
index d2fd493914..8fd9aad829 100755
--- a/tools/db/schema_diff.py
+++ b/tools/db/schema_diff.py
@@ -31,6 +31,9 @@ Run like:
 
     ./tools/db/schema_diff.py mysql master:latest my_branch:82
 """
+
+from __future__ import print_function
+
 import datetime
 import glob
 import os
@@ -191,19 +194,19 @@ def git_has_uncommited_changes():
 
 
 def die(msg):
-    print >> sys.stderr, "ERROR: %s" % msg
+    print("ERROR: %s" % msg, file=sys.stderr)
     sys.exit(1)
 
 
 def usage(msg=None):
     if msg:
-        print >> sys.stderr, "ERROR: %s" % msg
+        print("ERROR: %s" % msg, file=sys.stderr)
 
     prog = "schema_diff.py"
     args = ["<mysql|postgres>", "<orig-branch:orig-version>",
             "<new-branch:new-version>"]
 
-    print >> sys.stderr, "usage: %s %s" % (prog, ' '.join(args))
+    print("usage: %s %s" % (prog, ' '.join(args)), file=sys.stderr)
     sys.exit(1)
 
 
diff --git a/tools/install_venv.py b/tools/install_venv.py
index 8d30676df5..85d0c2794a 100644
--- a/tools/install_venv.py
+++ b/tools/install_venv.py
@@ -19,6 +19,8 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 
+from __future__ import print_function
+
 import os
 import sys
 
@@ -44,7 +46,7 @@ def print_help(venv, root):
 
     Also, make test will automatically use the virtualenv.
     """
-    print help % (venv, root)
+    print(help % (venv, root))
 
 
 def main(argv):
diff --git a/tools/lintstack.py b/tools/lintstack.py
index cda5f0b3d3..0240a43dc0 100755
--- a/tools/lintstack.py
+++ b/tools/lintstack.py
@@ -18,6 +18,8 @@
 
 """pylint error checking."""
 
+from __future__ import print_function
+
 import cStringIO as StringIO
 import json
 import re
@@ -114,9 +116,9 @@ class ErrorKeys(object):
 
     @classmethod
     def print_json(cls, errors, output=sys.stdout):
-        print >>output, "# automatically generated by tools/lintstack.py"
+        print("# automatically generated by tools/lintstack.py", file=output)
         for i in sorted(errors.keys()):
-            print >>output, json.dumps(i)
+            print(json.dumps(i), file=output)
 
     @classmethod
     def from_file(cls, filename):
@@ -139,7 +141,7 @@ def run_pylint():
 
 
 def generate_error_keys(msg=None):
-    print "Generating", KNOWN_PYLINT_EXCEPTIONS_FILE
+    print("Generating", KNOWN_PYLINT_EXCEPTIONS_FILE)
     if msg is None:
         msg = run_pylint()
     errors = LintOutput.from_msg_to_dict(msg)
@@ -148,30 +150,30 @@ def generate_error_keys(msg=None):
 
 
 def validate(newmsg=None):
-    print "Loading", KNOWN_PYLINT_EXCEPTIONS_FILE
+    print("Loading", KNOWN_PYLINT_EXCEPTIONS_FILE)
     known = ErrorKeys.from_file(KNOWN_PYLINT_EXCEPTIONS_FILE)
     if newmsg is None:
-        print "Running pylint. Be patient..."
+        print("Running pylint. Be patient...")
         newmsg = run_pylint()
     errors = LintOutput.from_msg_to_dict(newmsg)
 
-    print "Unique errors reported by pylint: was %d, now %d." \
-           % (len(known), len(errors))
+    print("Unique errors reported by pylint: was %d, now %d."
+           % (len(known), len(errors)))
     passed = True
     for err_key, err_list in errors.items():
         for err in err_list:
             if err_key not in known:
-                print err.lintoutput
-                print
+                print(err.lintoutput)
+                print()
                 passed = False
     if passed:
-        print "Congrats! pylint check passed."
+        print("Congrats! pylint check passed.")
         redundant = known - set(errors.keys())
         if redundant:
-            print "Extra credit: some known pylint exceptions disappeared."
+            print("Extra credit: some known pylint exceptions disappeared.")
             for i in sorted(redundant):
-                print json.dumps(i)
-            print "Consider regenerating the exception file if you will."
+                print(json.dumps(i))
+            print("Consider regenerating the exception file if you will.")
     else:
         print ("Please fix the errors above. If you believe they are false"
               " positives, run 'tools/lintstack.py generate' to overwrite.")
@@ -179,10 +181,10 @@ def validate(newmsg=None):
 
 
 def usage():
-    print """Usage: tools/lintstack.py [generate|validate]
+    print("""Usage: tools/lintstack.py [generate|validate]
     To generate pylint_exceptions file: tools/lintstack.py generate
     To validate the current commit: tools/lintstack.py
-    """
+    """)
 
 
 def main():
diff --git a/tools/regression_tester.py b/tools/regression_tester.py
index aabd0d7940..89a5a4dd29 100755
--- a/tools/regression_tester.py
+++ b/tools/regression_tester.py
@@ -32,6 +32,8 @@ Due to the risk of false positives, the results from this need some human
 interpretation.
 """
 
+from __future__ import print_function
+
 import optparse
 import string
 import subprocess
@@ -39,12 +41,12 @@ import sys
 
 
 def run(cmd, fail_ok=False):
-    print "running: %s" % cmd
+    print("running: %s" % cmd)
     obj = subprocess.Popen(cmd, stdout=subprocess.PIPE, stderr=subprocess.PIPE,
                            shell=True)
     obj.wait()
     if obj.returncode != 0 and not fail_ok:
-        print "The above command terminated with an error."
+        print("The above command terminated with an error.")
         sys.exit(obj.returncode)
     return obj.stdout.read()
 
@@ -95,13 +97,13 @@ def main():
         run("git checkout %s" % original_branch)
         run("git branch -D %s" % new_branch)
 
-    print expect_failure
-    print ""
-    print "*******************************"
+    print(expect_failure)
+    print("")
+    print("*******************************")
     if test_works:
-        print "FOUND a regression test"
+        print("FOUND a regression test")
     else:
-        print "NO regression test"
+        print("NO regression test")
         sys.exit(1)