From 9737938a4abb91f794621054288f85e172035681 Mon Sep 17 00:00:00 2001
From: Guo Xiang Tan <tgx_world@hotmail.com>
Date: Thu, 8 Nov 2018 12:28:50 +0800
Subject: [PATCH] Add option to skip tabels when using `DbHelper.remap`.

---
 lib/db_helper.rb           | 5 ++++-
 spec/lib/db_helper_spec.rb | 8 ++++++++
 2 files changed, 12 insertions(+), 1 deletion(-)

diff --git a/lib/db_helper.rb b/lib/db_helper.rb
index 15bed3c2579..04c9f8d3fb3 100644
--- a/lib/db_helper.rb
+++ b/lib/db_helper.rb
@@ -8,7 +8,7 @@ class DbHelper
        AND (data_type LIKE 'char%' OR data_type LIKE 'text%')
   ORDER BY table_name, column_name"
 
-  def self.remap(from, to, anchor_left = false, anchor_right = false)
+  def self.remap(from, to, anchor_left: false, anchor_right: false, exclude_tables: [])
     results = DB.query(REMAP_SQL).to_a
     like = "#{anchor_left ? '' : "%"}#{from}#{anchor_right ? '' : "%"}"
 
@@ -19,7 +19,10 @@ class DbHelper
       remappable_columns[result.table_name] << result.column_name
     end
 
+    exclude_tables = exclude_tables.map(&:to_s)
+
     remappable_columns.each do |table_name, column_names|
+      next if exclude_tables.include?(table_name)
       set_clause = column_names.map do |column_name|
         "#{column_name} = REPLACE(#{column_name}, :from, :to)"
       end.join(", ")
diff --git a/spec/lib/db_helper_spec.rb b/spec/lib/db_helper_spec.rb
index a99059591b4..e9d796257cf 100644
--- a/spec/lib/db_helper_spec.rb
+++ b/spec/lib/db_helper_spec.rb
@@ -32,5 +32,13 @@ RSpec.describe DbHelper do
       expect(badge_attributes.except("query"))
         .to eq(badge.attributes.except("query"))
     end
+
+    it 'allows tables to be excluded from scanning' do
+      post = Fabricate(:post, cooked: "test")
+
+      DbHelper.remap("test", "something else", exclude_tables: %w{posts})
+
+      expect(post.reload.cooked).to eq('test')
+    end
   end
 end