[Tests] More performance improvements

Most of the gained time is because some post tests don't recreate the
elastic index twice now.
Tests go from 107 seconds to 95 on my machine.

test/test_helper.rb

@@ -83,6 +83,12 @@ class ActiveSupport::TestCase
     mod.send(:remove_const, constant)
     mod.const_set(constant, old_value)
   end
+
+  def reset_post_index
+    # This seems slightly faster than deleting and recreating the index
+    Post.__elasticsearch__.client.delete_by_query(index: Post.index_name, q: "*", body: {})
+    Post.__elasticsearch__.refresh_index!
+  end
 end
 
 class ActionDispatch::IntegrationTest

test/unit/bulk_update_importer_importer_test.rb

@@ -22,7 +22,7 @@ class BulkUpdateRequestImporterTest < ActiveSupport::TestCase
 
     context "#estimate_update_count" do
       setup do
-        Post.__elasticsearch__.create_index! force: true
+        reset_post_index
         create(:post, tag_string: "aaa")
         create(:post, tag_string: "bbb")
         create(:post, tag_string: "ccc")

test/unit/bulk_update_request_test.rb

@@ -9,7 +9,7 @@ class BulkUpdateRequestTest < ActiveSupport::TestCase
 
     context "#estimate_update_count" do
       setup do
-        Post.__elasticsearch__.create_index! force: true
+        reset_post_index
         create(:post, tag_string: "aaa")
         create(:post, tag_string: "bbb")
         create(:post, tag_string: "ccc")

test/unit/post_test.rb

@@ -8,7 +8,7 @@ class PostTest < ActiveSupport::TestCase
   setup do
     @user = create(:user, created_at: 2.weeks.ago)
     CurrentUser.user = @user
-    Post.__elasticsearch__.create_index!
+    reset_post_index
   end
 
   context "Deletion:" do
@@ -1488,14 +1488,6 @@ class PostTest < ActiveSupport::TestCase
   end
 
   context "Searching:" do
-    setup do
-      Post.__elasticsearch__.create_index!
-    end
-
-    teardown do
-      Post.__elasticsearch__.delete_index!
-    end
-
     should "return posts for the age:<1minute tag" do
       post = create(:post)
       assert_tag_match([post], "age:<1minute")
@@ -2033,8 +2025,6 @@ class PostTest < ActiveSupport::TestCase
   # context "Counting:" do
   #   context "Creating a post" do
   #     setup do
-  #       Post.__elasticsearch__.delete_index!
-  #       Post.__elasticsearch__.create_index!
   #       create(:tag_alias, antecedent_name: "alias", consequent_name: "aaa")
   #       create(:post, tag_string: "aaa", score: 42)
   #     end
@@ -2105,7 +2095,6 @@ class PostTest < ActiveSupport::TestCase
   #         setup do
   #           CurrentUser.stubs(:safe_mode?).returns(true)
   #           create(:post, rating: "s")
-  #           Post.__elasticsearch__.refresh_index!
   #         end
   #
   #         should "work for a blank search" do

test/unit/related_tag_calculator_test.rb

@@ -4,7 +4,7 @@ class RelatedTagCalculatorTest < ActiveSupport::TestCase
   setup do
     user = create(:user)
     CurrentUser.user = user
-    Post.__elasticsearch__.create_index! force: true
+    reset_post_index
   end
 
   context "A related tag calculator" do

test/unit/tag_alias_test.rb

@@ -48,7 +48,7 @@ class TagAliasTest < ActiveSupport::TestCase
 
     context "#estimate_update_count" do
       setup do
-        Post.__elasticsearch__.create_index! force: true
+        reset_post_index
         create(:post, tag_string: "aaa bbb ccc")
         @alias = create(:tag_alias, antecedent_name: "aaa", consequent_name: "bbb", status: "pending")
       end

test/unit/tag_implication_test.rb

@@ -45,7 +45,7 @@ class TagImplicationTest < ActiveSupport::TestCase
 
     context "#estimate_update_count" do
       setup do
-        Post.__elasticsearch__.create_index! force: true
+        reset_post_index
         create(:post, tag_string: "aaa bbb ccc")
         @implication = create(:tag_implication, antecedent_name: "aaa", consequent_name: "bbb", status: "pending")
       end

test/unit/tag_test.rb

@@ -188,7 +188,7 @@ class TagTest < ActiveSupport::TestCase
 
   context "A tag with a negative post count" do
     should "be fixed" do
-      Post.__elasticsearch__.create_index! force: true
+      reset_post_index
       tag = create(:tag, name: "touhou", post_count: -10)
       post = create(:post, tag_string: "touhou")