Updated instructions for removing a column to append to ignored_colum…

…ns - closes #254

CHANGELOG.md

@@ -1,3 +1,7 @@
+## 1.7.1 (unreleased)
+
+- Updated instructions for removing a column to append to `ignored_columns`
+
 ## 1.7.0 (2024-01-05)
 
 - Added check for `add_unique_constraint`

README.md

@@ -38,7 +38,7 @@ Active Record caches attributes, which causes problems
 when removing columns. Be sure to ignore the column:
 
 class User < ApplicationRecord
-  self.ignored_columns = ["name"]
+  self.ignored_columns += ["name"]
 end
 
 Deploy the code, then wrap this step in a safety_assured { ... } block.
@@ -110,7 +110,7 @@ end
 
   ```ruby
   class User < ApplicationRecord
-    self.ignored_columns = ["some_column"]
+    self.ignored_columns += ["some_column"]
   end
   ```
 

lib/strong_migrations/checks.rb

@@ -353,7 +353,7 @@ def check_remove_column(method, *args)
           cols
         end
 
-      code = "self.ignored_columns = #{columns.inspect}"
+      code = "self.ignored_columns += #{columns.inspect}"
 
       raise_error :remove_column,
         model: args[0].to_s.classify,

test/remove_column_test.rb

@@ -10,7 +10,7 @@ def test_remove_columns
   end
 
   def test_remove_columns_type
-    assert_unsafe RemoveColumnsType, 'self.ignored_columns = ["name", "other"]'
+    assert_unsafe RemoveColumnsType, 'self.ignored_columns += ["name", "other"]'
   end
 
   def test_remove_timestamps