Fixed constraint name for long table and column names with change_col…

…umn_null - fixes #291

CHANGELOG.md

@@ -1,3 +1,7 @@
+## 2.1.1 (unreleased)
+
+- Fixed constraint name for long table and column names with `change_column_null`
+
 ## 2.1.0 (2024-11-08)
 
 - Added `skip_database` method

lib/strong_migrations/checks.rb

@@ -232,10 +232,21 @@ def check_change_column_null(*args)
           safe = constraints.any? { |c| c.options[:validate] && (c.expression == "#{column} IS NOT NULL" || c.expression == "#{connection.quote_column_name(column)} IS NOT NULL") }
 
           unless safe
+            expression = "#{quote_column_if_needed(column)} IS NOT NULL"
+
             # match https://github.com/nullobject/rein
             constraint_name = "#{table}_#{column}_null"
+            # 63 characters is max length for Postgres, 64 characters for MySQL and MariaDB
+            if constraint_name.bytesize > 63
+              constraint_name = connection.check_constraint_options(table, expression, {})[:name]
+
+              # avoid collision with Active Record naming for safe_by_default
+              if StrongMigrations.safe_by_default
+                constraint_name = constraint_name.sub("rails", "strong")
+              end
+            end
 
-            add_args = [table, "#{quote_column_if_needed(column)} IS NOT NULL", {name: constraint_name, validate: false}]
+            add_args = [table, expression, {name: constraint_name, validate: false}]
             validate_args = [table, {name: constraint_name}]
             change_args = [table, column, null]
             remove_args = [table, {name: constraint_name}]

test/migrations/change_column_null.rb

@@ -83,3 +83,11 @@ def down
     change_column_null :users, :interval, true
   end
 end
+
+class ChangeColumnNullLongName < TestMigration
+  def change
+    column = "a"*60
+    add_column :users, column, :string
+    change_column_null :users, column, false
+  end
+end

test/safe_by_default_test.rb

@@ -235,4 +235,10 @@ def test_change_column_null_invalid
   ensure
     User.delete_all
   end
+
+  def test_change_column_null_long_name
+    skip unless postgresql?
+
+    assert_safe ChangeColumnNullLongName
+  end
 end