Exclude not critical test (#2)

* Exclude not critical test

* Add exclude-tests option

* Update documentation

* Clean forgotten print

* Improve Readme, with examples

django_migration_linter/management/commands/lintmigrations.py

@@ -50,6 +50,10 @@ class Command(BaseCommand):
             "--project-root-path", type=str, nargs="?", help="django project root path"
         )
 
+        parser.add_argument(
+            "--exclude-tests", type=str, nargs="*", help="Specify tests to be ignored (e.g. ALTER_COLUMN)"
+        )
+
         cache_group = parser.add_mutually_exclusive_group(required=False)
         cache_group.add_argument(
             "--cache-path",
@@ -107,6 +111,7 @@ class Command(BaseCommand):
             ignore_name=options["ignore_name"],
             include_apps=options["include_apps"],
             exclude_apps=options["exclude_apps"],
+            exclude_tests=options["exclude_tests"],
             database=options["database"],
             cache_path=options["cache_path"],
             no_cache=options["no_cache"],

django_migration_linter/migration_linter.py

@@ -42,6 +42,7 @@ class MigrationLinter(object):
         ignore_name=None,
         include_apps=None,
         exclude_apps=None,
+        exclude_tests=None,
         database=DEFAULT_DB_ALIAS,
         cache_path=DEFAULT_CACHE_PATH,
         no_cache=False,
@@ -54,6 +55,7 @@ class MigrationLinter(object):
         self.ignore_name = ignore_name or tuple()
         self.include_apps = include_apps
         self.exclude_apps = exclude_apps
+        self.exclude_tests = exclude_tests
         self.database = database or DEFAULT_DB_ALIAS
         self.cache_path = cache_path or DEFAULT_CACHE_PATH
         self.no_cache = no_cache
@@ -118,7 +120,8 @@ class MigrationLinter(object):
             return
 
         sql_statements = self.get_sql(app_label, migration_name)
-        errors = analyse_sql_statements(sql_statements)
+        exclude_tests = self.exclude_tests or []
+        errors = analyse_sql_statements(sql_statements, exclude_tests)
 
         if not errors:
             print("OK")

django_migration_linter/sql_analyser.py

@@ -70,11 +70,11 @@ migration_tests = (
 )
 
 
-def analyse_sql_statements(sql_statements):
+def analyse_sql_statements(sql_statements, exclude_tests):
     errors = []
     for statement in sql_statements:
         for test in migration_tests:
-            if test["fn"](statement, errors=errors):
+            if test["code"] not in exclude_tests and test["fn"](statement, errors=errors):
                 logger.debug("Testing {0} -- ERROR".format(statement))
                 table_search = re.search("TABLE `([^`]*)`", statement, re.IGNORECASE)
                 col_search = re.search("COLUMN `([^`]*)`", statement, re.IGNORECASE)