Handle creating a unique index as adding a unique constraint

CHANGELOG.md

@@ -5,6 +5,7 @@
 - Drop support for Django 1.11, 2.0, 2.1, 3.0 and 3.1
 - Add support for Django 4.0
 - Fix index creation detection when table is being created in the transaction (issue #178)
+- Handle unique index creation as adding a unique constraint (issue #183)
 
 ## 3.0.1
 

django_migration_linter/sql_analyser/base.py

@@ -26,7 +26,9 @@ def has_not_null_column(sql_statements, **kwargs):
 def has_add_unique(sql_statements, **kwargs):
     regex_result = None
     for sql in sql_statements:
-        regex_result = re.search("ALTER TABLE (.*) ADD CONSTRAINT .* UNIQUE", sql)
+        regex_result = re.search(
+            "ALTER TABLE (.*) ADD CONSTRAINT .* UNIQUE", sql
+        ) or re.search('CREATE UNIQUE INDEX .* ON (".*?")', sql)
         if regex_result:
             break
     if not regex_result:

django_migration_linter/sql_analyser/sqlite.py

@@ -3,23 +3,6 @@ import re
 from .base import BaseAnalyser
 
 
-def has_add_unique(sql_statements, **kwargs):
-    regex_result = None
-    for sql in sql_statements:
-        regex_result = re.search('CREATE UNIQUE INDEX .* ON (".*?")', sql)
-        if regex_result:
-            break
-    if not regex_result:
-        return False
-
-    concerned_table = regex_result.group(1)
-    table_is_added_in_transaction = any(
-        sql.startswith("CREATE TABLE {}".format(concerned_table))
-        for sql in sql_statements
-    )
-    return not table_is_added_in_transaction
-
-
 class SqliteAnalyser(BaseAnalyser):
     migration_tests = [
         {
@@ -54,12 +37,6 @@ class SqliteAnalyser(BaseAnalyser):
             "mode": "transaction",
             "type": "error",
         },
-        {
-            "code": "ADD_UNIQUE",
-            "fn": has_add_unique,
-            "mode": "transaction",
-            "type": "error",
-        },
     ]
 
     @staticmethod

tests/unit/test_sql_analyser.py

@@ -21,9 +21,16 @@ class SqlAnalyserTestCase(unittest.TestCase):
                 0, len(warnings), "Found warnings in sql: {}".format(errors)
             )
 
-    def assertBackwardIncompatibleSql(self, sql):
+    def assertBackwardIncompatibleSql(self, sql, code=None):
         errors, _, _ = self.analyse_sql(sql)
         self.assertNotEqual(0, len(errors), "Found no errors in sql")
+        if code:
+            self.assertTrue(
+                any(err["code"] == code for err in errors),
+                "Didn't find error code {} in returned errors ({})".format(
+                    code, [err["code"] for err in errors]
+                ),
+            )
 
     def assertWarningSql(self, sql):
         _, _, warnings = self.analyse_sql(sql)
@@ -63,6 +70,16 @@ class MySqlAnalyserTestCase(SqlAnalyserTestCase):
         sql = "ALTER TABLE `app_unique_together_a` DROP INDEX `app_unique_together_a_int_field_char_field_979ac7d8_uniq`;"
         self.assertValidSql(sql)
 
+    def test_unique_index(self):
+        sql = 'CREATE UNIQUE INDEX "index_name" ON "table" ("col1", "col2");'
+        self.assertBackwardIncompatibleSql(sql, "ADD_UNIQUE")
+
+        sql = [
+            'CREATE TABLE "table" ("col1" integer, "col2" integer);',
+            'CREATE UNIQUE INDEX "index_name" ON "table" ("col1", "col2");',
+        ]
+        self.assertValidSql(sql)
+
     def test_add_many_to_many_field(self):
         sql = [
             "CREATE TABLE `app_add_manytomany_field_b_many_to_many`(`id` integer AUTO_INCREMENT NOT NULL PRIMARY KEY, `b_id` integer NOT NULL, `a_id` integer NOT NULL);",
@@ -146,6 +163,16 @@ class SqliteAnalyserTestCase(SqlAnalyserTestCase):
         sql = 'DROP INDEX "app_unique_together_a_int_field_char_field_979ac7d8_uniq";'
         self.assertValidSql(sql)
 
+    def test_unique_index(self):
+        sql = 'CREATE UNIQUE INDEX "index_name" ON "table" ("col1", "col2");'
+        self.assertBackwardIncompatibleSql(sql, "ADD_UNIQUE")
+
+        sql = [
+            'CREATE TABLE "table" ("col1" integer, "col2" integer);',
+            'CREATE UNIQUE INDEX "index_name" ON "table" ("col1", "col2");',
+        ]
+        self.assertValidSql(sql)
+
     def test_add_many_to_many_field(self):
         sql = [
             'CREATE TABLE "app_add_manytomany_field_b_many_to_many"("id" integer NOT NULL PRIMARY KEY AUTOINCREMENT, "b_id" integer NOT NULL REFERENCES "app_add_manytomany_field_b"("id") DEFERRABLE INITIALLY DEFERRED, "a_id" integer NOT NULL REFERENCES "app_add_manytomany_field_a"("id") DEFERRABLE INITIALLY DEFERRED);',
@@ -197,6 +224,16 @@ class PostgresqlAnalyserTestCase(SqlAnalyserTestCase):
         sql = 'ALTER TABLE "app_unique_together_a" DROP CONSTRAINT "app_unique_together_a_int_field_char_field_979ac7d8_uniq";'
         self.assertValidSql(sql)
 
+    def test_unique_index(self):
+        sql = 'CREATE UNIQUE INDEX "index_name" ON "table" ("col1", "col2");'
+        self.assertBackwardIncompatibleSql(sql, "ADD_UNIQUE")
+
+        sql = [
+            'CREATE TABLE "table" ("col1" integer, "col2" integer);',
+            'CREATE UNIQUE INDEX "index_name" ON "table" ("col1", "col2");',
+        ]
+        self.assertValidSql(sql)
+
     def test_add_many_to_many_field(self):
         sql = [
             'CREATE TABLE "app_add_manytomany_field_b_many_to_many"("id" serial NOT NULL PRIMARY KEY, "b_id" integer NOT NULL, "a_id" integer NOT NULL);',