Add unit test for new IgnoreUnknown flag

Author: Will Dixon

migrate_test.go

@@ -516,6 +516,47 @@ func (s *SqliteMigrateSuite) TestPlanMigrationWithUnknownDatabaseMigrationApplie
 	c.Assert(err, FitsTypeOf, &PlanError{})
 }
 
+func (s *SqliteMigrateSuite) TestPlanMigrationWithIgnoredUnknownDatabaseMigrationApplied(c *C) {
+	migrations := &MemoryMigrationSource{
+		Migrations: []*Migration{
+			&Migration{
+				Id:   "1_create_table.sql",
+				Up:   []string{"CREATE TABLE people (id int)"},
+				Down: []string{"DROP TABLE people"},
+			},
+			&Migration{
+				Id:   "2_alter_table.sql",
+				Up:   []string{"ALTER TABLE people ADD COLUMN first_name text"},
+				Down: []string{"SELECT 0"}, // Not really supported
+			},
+			&Migration{
+				Id:   "10_add_last_name.sql",
+				Up:   []string{"ALTER TABLE people ADD COLUMN last_name text"},
+				Down: []string{"ALTER TABLE people DROP COLUMN last_name"},
+			},
+		},
+	}
+	SetIgnoreUnknown(true)
+	n, err := Exec(s.Db, "sqlite3", migrations, Up)
+	c.Assert(err, IsNil)
+	c.Assert(n, Equals, 3)
+
+	// Note that migration 10_add_last_name.sql is missing from the new migrations source
+	// so it is considered an "unknown" migration for the planner.
+	migrations.Migrations = append(migrations.Migrations[:2], &Migration{
+		Id:   "10_add_middle_name.sql",
+		Up:   []string{"ALTER TABLE people ADD COLUMN middle_name text"},
+		Down: []string{"ALTER TABLE people DROP COLUMN middle_name"},
+	})
+
+	_, _, err = PlanMigration(s.Db, "sqlite3", migrations, Up, 0)
+	c.Assert(err, IsNil)
+
+	_, _, err = PlanMigration(s.Db, "sqlite3", migrations, Down, 0)
+	c.Assert(err, IsNil)
+	SetIgnoreUnknown(false) // Make sure we are not breaking other tests as this is globaly set
+}
+
 // TestExecWithUnknownMigrationInDatabase makes sure that problems found with planning the
 // migrations are propagated and returned by Exec.
 func (s *SqliteMigrateSuite) TestExecWithUnknownMigrationInDatabase(c *C) {