Create shard 3 for bok-choy; handle unknown shards.

This accomplishes three things:
1. Create a 3rd bok-choy shard
2. Allow the script to run 'all' shards
3. If the script receives an unknown shard, it will pass through empty tests.

The last one (3) is intended to allow us to expand to additional shards
on our Jenkins infrastructure. If we have, for example, a 4th shard introduced,
but someone attemps to run a commit that is older (and therefore still
has 3 shards); the script will just pass-through shard '4'. This means
older commits can still get tested. In that case, the older commit
will still test all cases, because the last shard (n) is basically an
'everything else' shard.

scripts/all-tests.sh

@@ -24,19 +24,19 @@ set -e
 #
 #   `SHARD` is a number (1, 2, or 3) indicating which subset of the tests
 #       to build.  Currently, "lms-acceptance" and "bok-choy" each have two
-#       shards (1 and 2), "cms-acceptance" has three shards (1, 2, and 3), 
-#       and all the other test suites have one shard.  
-# 
-#       For the "bok-choy", the tests are put into shard groups using the nose 
-#       'attr' decorator (e.g. "@attr('shard_1')").  Currently, anything with 
+#       shards (1 and 2), "cms-acceptance" has three shards (1, 2, and 3),
+#       and all the other test suites have one shard.
+#
+#       For the "bok-choy", the tests are put into shard groups using the nose
+#       'attr' decorator (e.g. "@attr('shard_1')").  Currently, anything with
 #       the 'shard_1' attribute will run in the first shard.  All other bok-choy
 #       tests will run in shard 2.
-# 
-#       For the lettuce acceptance tests, ("lms-" and "cms-acceptance") they 
+#
+#       For the lettuce acceptance tests, ("lms-" and "cms-acceptance") they
 #       are decorated with "@shard_{}" (e.g. @shard_1 for the first shard).
 #       The lettuce tests must have a shard specified to be run in jenkins,
 #       as there is no shard that runs unspecified tests.
-# 
+#
 #
 #   Jenkins configuration:
 #
@@ -93,6 +93,13 @@ fi
 # Activate the Python virtualenv
 source $HOME/edx-venv/bin/activate
 
+# If the environment variable 'SHARD' is not set, default to 'all'.
+# This could happen if you are trying to use this script from
+# jenkins and do not define 'SHARD' in your multi-config project.
+# Note that you will still need to pass a value for 'TEST_SUITE'
+# or else no tests will be executed.
+SHARD=${SHARD:="all"}
+
 case "$TEST_SUITE" in
 
     "quality")
@@ -117,24 +124,74 @@ END
         ;;
 
     "lms-acceptance")
-        paver test_acceptance -s lms --extra_args="-v 3 --tag shard_${SHARD}"
+        case "$SHARD" in
+
+            "all")
+                paver test_acceptance -s lms --extra_args="-v 3"
+                ;;
+
+            *)
+                paver test_acceptance -s lms --extra_args="-v 3 --tag shard_${SHARD}"
+                ;;
+        esac
         ;;
 
     "cms-acceptance")
-        paver test_acceptance -s cms --extra_args="-v 3 --tag shard_${SHARD}"
+        case "$SHARD" in
+
+            "all")
+                paver test_acceptance -s cms --extra_args="-v 3"
+                ;;
+
+            *)
+                paver test_acceptance -s cms --extra_args="-v 3 --tag shard_${SHARD}"
+                ;;
+        esac
         ;;
 
     "bok-choy")
         case "$SHARD" in
+
+            "all")
+                paver test_bokchoy
+                paver bokchoy_coverage
+                ;;
+
             "1")
                 paver test_bokchoy --extra_args="-a shard_1"
+                paver bokchoy_coverage
                 ;;
 
             "2")
-                paver test_bokchoy --extra_args="-a '!shard_1'"
-               ;;
+                paver test_bokchoy --extra_args="-a 'shard_2'"
+                paver bokchoy_coverage
+                ;;
+
+            "3")
+                paver test_bokchoy --extra_args="-a shard_1=False,shard_2=False"
+                paver bokchoy_coverage
+                ;;
+
+            # Default case because if we later define another bok-choy shard on Jenkins
+            # (e.g. Shard 4) in the multi-config project and expand this file
+            # with an additional case condition, old branches without that commit
+            # would not execute any tests on the worker assigned to that shard
+            # and thus their build would fail.
+            # This way they will just report 1 test executed and passed.
+            *)
+                # Need to create an empty test result so the post-build
+                # action doesn't fail the build.
+                # May be unnecessary if we changed the "Skip if there are no test files"
+                # option to True in the jenkins job definitions.
+                mkdir -p reports
+                cat > reports/bok_choy/xunit.xml <<END
+<?xml version="1.0" encoding="UTF-8"?>
+<testsuite name="nosetests" tests="1" errors="0" failures="0" skip="0">
+<testcase classname="acceptance.tests" name="shard_placeholder" time="0.001"></testcase>
+</testsuite>
+END
+                ;;
         esac
-        paver bokchoy_coverage
         ;;
 
 esac