Merge pull request #38444 from eileencodes/add-schema-cache-tests-and-fix-one-more-bug

Add schema cache tests

railties/test/application/rake/dbs_test.rb

@@ -361,6 +361,82 @@ module ApplicationTests
         db_schema_dump
       end
 
+      def db_schema_cache_dump(filename = "db/schema_cache.yml")
+        Dir.chdir(app_path) do
+          rails "db:schema:cache:dump"
+
+          cache_size = lambda { rails("runner", "p ActiveRecord::Base.connection.schema_cache.size").strip }
+          cache_tables = lambda { rails("runner", "p ActiveRecord::Base.connection.schema_cache.columns('books')").strip }
+
+          assert_equal "12", cache_size[]
+          assert_includes cache_tables[], "id", "expected cache_tables to include an id entry"
+          assert_includes cache_tables[], "title", "expected cache_tables to include a title entry"
+        end
+      end
+
+      test "db:schema:cache:dump" do
+        db_schema_dump
+        db_schema_cache_dump
+      end
+
+      test "db:schema:cache:dump with custom filename" do
+        Dir.chdir(app_path) do
+          File.open("#{app_path}/config/database.yml", "w") do |f|
+            f.puts <<-YAML
+            default: &default
+              adapter: sqlite3
+              pool: 5
+              timeout: 5000
+              variables:
+                statement_timeout: 1000
+            development:
+              <<: *default
+              database: db/development.sqlite3
+              schema_cache_path: db/special_schema_cache.yml
+            YAML
+          end
+        end
+
+        db_schema_dump
+        db_schema_cache_dump("db/special_schema_cache.yml")
+      end
+
+      test "db:schema:cache:dump custom env" do
+        @old_schema_cache_env = ENV["SCHEMA_CACHE"]
+        filename = "db/special_schema_cache.yml"
+        ENV["SCHEMA_CACHE"] = filename
+
+        db_schema_dump
+        db_schema_cache_dump(filename)
+      ensure
+        ENV["SCHEMA_CACHE"] = @old_schema_cache_env
+      end
+
+      test "db:schema:cache:dump primary wins" do
+        Dir.chdir(app_path) do
+          File.open("#{app_path}/config/database.yml", "w") do |f|
+            f.puts <<-YAML
+            default: &default
+              adapter: sqlite3
+              pool: 5
+              timeout: 5000
+              variables:
+                statement_timeout: 1000
+            development:
+              some_entry:
+                <<: *default
+                database: db/development_other.sqlite3
+              primary:
+                <<: *default
+                database: db/development.sqlite3
+            YAML
+          end
+        end
+
+        db_schema_dump
+        db_schema_cache_dump
+      end
+
       def db_fixtures_load(expected_database)
         Dir.chdir(app_path) do
           rails "generate", "model", "book", "title:string"

railties/test/application/rake/multi_dbs_test.rb

@@ -311,6 +311,25 @@ module ApplicationTests
         db_migrate_and_schema_cache_dump
       end
 
+      # Note that schema cache loader depends on the connection and
+      # does not work for all connections.
+      test "schema_cache is loaded on primary db in multi-db app" do
+        require "#{app_path}/config/environment"
+        db_migrate_and_schema_cache_dump
+
+        cache_size_a = lambda { rails("runner", "p ActiveRecord::Base.connection.schema_cache.size").strip }
+        cache_tables_a = lambda { rails("runner", "p ActiveRecord::Base.connection.schema_cache.columns('books')").strip }
+        cache_size_b = lambda { rails("runner", "p AnimalsBase.connection.schema_cache.size").strip }
+        cache_tables_b = lambda { rails("runner", "p AnimalsBase.connection.schema_cache.columns('dogs')").strip }
+
+        assert_equal "12", cache_size_a[]
+        assert_includes cache_tables_a[], "title", "expected cache_tables_a to include a title entry"
+
+        # Will be 0 because it's not loaded by the railtie
+        assert_equal "0", cache_size_b[]
+        assert_includes cache_tables_b[], "name", "expected cache_tables_b to include a name entry"
+      end
+
       test "db:schema:cache:clear works on all databases" do
         require "#{app_path}/config/environment"
         db_migrate_and_schema_cache_dump_and_schema_cache_clear