Merge issuable "reopened" state into "opened"

Having two states that essentially mean the same thing is very much like
having a boolean "true" and boolean "mostly-true": it's rather silly.
This commit merges the "reopened" state into the "opened" state while
taking care of system notes still showing messages along the lines of
"Alice reopened this issue".

A big benefit from having only two states (opened and closed) is that
indexing and querying becomes simpler and more performant. For example,
to get all the opened queries we no longer have to query both states:

    SELECT *
    FROM issues
    WHERE project_id = 2
    AND state IN ('opened', 'reopened');

Instead we can query a single state directly, which can be much faster:

    SELECT *
    FROM issues
    WHERE project_id = 2
    AND state = 'opened';

Further, only having two states makes indexing easier as we will only
ever filter (and thus scan an index) using a single value. Partial
indexes could help but aren't supported on MySQL, complicating the
development process and not being helpful for MySQL.

2 files changed, 2 insertions, 10 deletions

diff --git a/spec/factories/issues.rb b/spec/factories/issues.rb
index f1fd1fd7f73..a16695cb7c1 100644
--- a/spec/factories/issues.rb
+++ b/spec/factories/issues.rb
@@ -16,12 +16,8 @@ FactoryGirl.define do
       state :closed
     end
 
-    trait :reopened do
-      state :reopened
-    end
-
     factory :closed_issue, traits: [:closed]
-    factory :reopened_issue, traits: [:reopened]
+    factory :reopened_issue, traits: [:opened]
 
     factory :labeled_issue do
       transient do
diff --git a/spec/factories/merge_requests.rb b/spec/factories/merge_requests.rb
index 253a025af48..1bc530d06db 100644
--- a/spec/factories/merge_requests.rb
+++ b/spec/factories/merge_requests.rb
@@ -44,10 +44,6 @@ FactoryGirl.define do
       state :opened
     end
 
-    trait :reopened do
-      state :reopened
-    end
-
     trait :locked do
       state :locked
     end
@@ -74,7 +70,7 @@ FactoryGirl.define do
 
     factory :merged_merge_request, traits: [:merged]
     factory :closed_merge_request, traits: [:closed]
-    factory :reopened_merge_request, traits: [:reopened]
+    factory :reopened_merge_request, traits: [:opened]
     factory :merge_request_with_diffs, traits: [:with_diffs]
     factory :merge_request_with_diff_notes do
       after(:create) do |mr|