Fix migrations for postgres on test environment

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

db/migrate/20140122112253_create_merge_request_diffs.rb

@@ -2,11 +2,16 @@ class CreateMergeRequestDiffs < ActiveRecord::Migration
   def change
     create_table :merge_request_diffs do |t|
       t.string :state, null: false, default: 'collected'
-      t.text :st_commits, null: true, limit: 2147483647
-      t.text :st_diffs, null: true, limit: 2147483647
+      t.text :st_commits, null: true
+      t.text :st_diffs, null: true
       t.integer :merge_request_id, null: false
 
       t.timestamps
     end
+
+    if ActiveRecord::Base.configurations[Rails.env]['adapter'] =~ /^mysql/
+      change_column :merge_request_diffs, :st_commits, :text, limit: 2147483647
+      change_column :merge_request_diffs, :st_diffs, :text, limit: 2147483647
+    end
   end
 end

db/migrate/20140903115954_migrate_to_new_shell.rb

 class MigrateToNewShell < ActiveRecord::Migration
   def change
+    return if Rails.env.test?
+
     gitlab_shell_path = Gitlab.config.gitlab_shell.path
     if system("#{gitlab_shell_path}/bin/create-hooks")
       puts 'Repositories updated with new hooks'