{ "info": { "exit_status": "Submitted", "submission": "diff --git a/django/db/models/expressions.py b/django/db/models/expressions.py\nindex 822968ef56..02a49836d7 100644\n--- a/django/db/models/expressions.py\n+++ b/django/db/models/expressions.py\n@@ -1299,6 +1299,10 @@ class When(Expression):\n template_params = extra_context\n sql_params = []\n condition_sql, condition_params = compiler.compile(self.condition)\n+ # If condition is empty (matches everything), use a condition that always evaluates to true\n+ if not condition_sql:\n+ condition_sql = \"1=1\"\n+ condition_params = []\n template_params[\"condition\"] = condition_sql\n sql_params.extend(condition_params)\n result_sql, result_params = compiler.compile(self.result)", "model_stats": { "instance_cost": 0.32052914999999993, "api_calls": 35 } }, "messages": [ { "role": "system", "content": "You are a helpful assistant that can interact multiple times with a computer shell to solve programming tasks.\nYour response must contain exactly ONE bash code block with ONE command (or commands connected with && or ||).\n\nInclude a THOUGHT section before your command where you explain your reasoning process.\nFormat your response as shown in .\n\n\nTHOUGHT: Your reasoning and analysis here\n\n```bash\nyour_command_here\n```\n\n\nFailure to follow these rules will cause your response to be rejected.\n" }, { "role": "user", "content": [ { "type": "text", "text": "\nConsider the following PR description:\nCase() crashes with ~Q(pk__in=[]).\nDescription\n\t\nThe following code generates a syntax error. \nUser.objects.annotate(\n\t_a=Case(\n\t\tWhen(~Q(pk__in=[]), then=Value(True)),\n\t\tdefault=Value(False),\n\t\toutput_field=BooleanField(),\n\t)\n).order_by(\"-a\").values(\"pk\")\nThe error is: \nProgrammingError: syntax error at or near \"THEN\"\nLINE 1: ..._user\".\"id\" FROM \"users_user\" ORDER BY CASE WHEN THEN true ...\nThe generated SQL is: \nSELECT \"users_user\".\"id\" FROM \"users_user\" ORDER BY CASE WHEN THEN True ELSE False END ASC\nI expected behavior to annotate all rows with the value True since they all match.\nRelevant because ~Q(pkin=[]) is a sentinel value that is sometimes returned by application code.\n\n\n\n\n# Task Instructions\n\n## Overview\nYou're a software engineer interacting continuously with a computer by submitting commands.\nYou'll be helping implement necessary changes to meet requirements in the PR description.\nYour task is specifically to make changes to non-test files in the current directory in order to fix the issue described in the PR description in a way that is general and consistent with the codebase.\n\nIMPORTANT: This is an interactive process where you will think and issue ONE command, see its result, then think and issue your next command.\n\nFor each response:\n1. Include a THOUGHT section explaining your reasoning and what you're trying to accomplish\n2. Provide exactly ONE bash command to execute\n\n## Important Boundaries\n- MODIFY: Regular source code files in \n- DO NOT MODIFY: Tests, configuration files (pyproject.toml, setup.cfg, etc.)\n\n## Recommended Workflow\n1. Analyze the codebase by finding and reading relevant files\n2. Create a script to reproduce the issue\n3. Edit the source code to resolve the issue\n4. Verify your fix works by running your script again\n5. Test edge cases to ensure your fix is robust\n\n## Command Execution Rules\nYou are operating in an environment where\n1. You write a single command\n2. The system executes that command in a subshell\n3. You see the result\n4. You write your next command\n\nEach response should include:\n1. A **THOUGHT** section where you explain your reasoning and plan\n2. A single bash code block with your command\n\nFormat your responses like this:\n\n\nTHOUGHT: Here I explain my reasoning process, analysis of the current situation,\nand what I'm trying to accomplish with the command below.\n\n```bash\nyour_command_here\n```\n\n\nCommands must be specified in a single bash code block:\n\n```bash\nyour_command_here\n```\n\n**CRITICAL REQUIREMENTS:**\n- Your response SHOULD include a THOUGHT section explaining your reasoning\n- Your response MUST include EXACTLY ONE bash code block\n- This bash block MUST contain EXACTLY ONE command (or a set of commands connected with && or ||)\n- If you include zero or multiple bash blocks, or no command at all, YOUR RESPONSE WILL FAIL\n- Do NOT try to run multiple independent commands in separate blocks in one response\n- Directory or environment variable changes are not persistent. Every action is executed in a new subshell.\n- However, you can prefix any action with `MY_ENV_VAR=MY_VALUE cd /path/to/working/dir && ...` or write/load environment variables from files\n\nExample of a CORRECT response:\n\nTHOUGHT: I need to understand the structure of the repository first. Let me check what files are in the current directory to get a better understanding of the codebase.\n\n```bash\nls -la\n```\n\n\nExample of an INCORRECT response:\n\nTHOUGHT: I need to examine the codebase and then look at a specific file. I'll run multiple commands to do this.\n\n```bash\nls -la\n```\n\nNow I'll read the file:\n\n```bash\ncat file.txt\n```\n\n\nIf you need to run multiple commands, either:\n1. Combine them in one block using && or ||\n```bash\ncommand1 && command2 || echo \"Error occurred\"\n```\n\n2. Wait for the first command to complete, see its output, then issue the next command in your following response.\n\n## Environment Details\n- You have a full Linux shell environment\n- Always use non-interactive flags (-y, -f) for commands\n- Avoid interactive tools like vi, nano, or any that require user input\n- If a command isn't available, you can install it\n\n## Useful Command Examples\n\n### Create a new file:\n```bash\ncat <<'EOF' > newfile.py\nimport numpy as np\nhello = \"world\"\nprint(hello)\nEOF\n```\n\n### Edit files with sed:\n```bash\n# Replace all occurrences\nsed -i 's/old_string/new_string/g' filename.py\n\n# Replace only first occurrence\nsed -i 's/old_string/new_string/' filename.py\n\n# Replace first occurrence on line 1\nsed -i '1s/old_string/new_string/' filename.py\n\n# Replace all occurrences in lines 1-10\nsed -i '1,10s/old_string/new_string/g' filename.py\n```\n\n### View file content:\n```bash\n# View specific lines with numbers\nnl -ba filename.py | sed -n '10,20p'\n```\n\n### Any other command you want to run\n```bash\nanything\n```\n\n## Submission\nWhen you've completed your changes or can't make further progress\nissue exactly the following command:\n\n```bash\necho MICRO_SWE_AGENT_FINAL_OUTPUT && git add -A && git diff --cached\n```\n\nThis command will submit your changes.\nYou cannot continue working on this task after submitting.\n" } ] }, { "role": "assistant", "content": "THOUGHT: I need to understand the structure of the repository and find the relevant files related to Django's Case and Q objects. Let me start by exploring the current directory to understand the codebase structure.\n\n```bash\nls -la\n```" }, { "role": "user", "content": [ { "type": "text", "text": "0\n\ntotal 188\ndrwxrwxrwx 1 root root 4096 Oct 24 2024 .\ndrwxr-xr-x 1 root root 4096 Jul 22 03:11 ..\n-rw-r--r-- 1 root root 806 Oct 24 2024 .editorconfig\n-rw-r--r-- 1 root root 120 Oct 24 2024 .eslintignore\n-rw-r--r-- 1 root root 1407 Oct 24 2024 .eslintrc\ndrwxrwxrwx 8 root root 4096 Oct 24 2024 .git\n-rw-r--r-- 1 root root 205 Oct 24 2024 .git-blame-ignore-revs\n-rw-r--r-- 1 root root 297 Oct 24 2024 .gitattributes\ndrwxrwxrwx 3 root root 4096 Oct 24 2024 .github\n-rw-r--r-- 1 root root 353 Oct 24 2024 .gitignore\n-rw-r--r-- 1 root root 389 Oct 24 2024 .pre-commit-config.yaml\n-rw-r--r-- 1 root root 385 Oct 24 2024 .readthedocs.yml\ndrwxrwxrwx 2 root root 4096 Oct 24 2024 .tx\n-rw-r--r-- 1 root root 40674 Oct 24 2024 AUTHORS\n-rw-r--r-- 1 root root 1115 Oct 24 2024 CONTRIBUTING.rst\ndrwxr-xr-x 2 root root 4096 Oct 24 2024 Django.egg-info\n-rw-r--r-- 1 root root 369 Oct 24 2024 Gruntfile.js\n-rw-r--r-- 1 root root 236 Oct 24 2024 INSTALL\n-rw-r--r-- 1 root root 1552 Oct 24 2024 LICENSE\n-rw-r--r-- 1 root root 14383 Oct 24 2024 LICENSE.python\n-rw-r--r-- 1 root root 276 Oct 24 2024 MANIFEST.in\n-rw-r--r-- 1 root root 2122 Oct 24 2024 README.rst\ndrwxrwxrwx 18 root root 4096 Oct 24 2024 django\ndrwxrwxrwx 13 root root 4096 Oct 24 2024 docs\ndrwxrwxrwx 2 root root 4096 Oct 24 2024 extras\ndrwxrwxrwx 4 root root 4096 Oct 24 2024 js_tests\n-rw-r--r-- 1 root root 363 Oct 24 2024 package.json\n-rw-r--r-- 1 root root 219 Oct 24 2024 pyproject.toml\ndrwxrwxrwx 2 root root 4096 Oct 24 2024 scripts\n-rw-r--r-- 1 root root 2276 Oct 24 2024 setup.cfg\n-rw-r--r-- 1 root root 1633 Oct 24 2024 setup.py\ndrwxrwxrwx 215 root root 12288 Oct 24 2024 tests\n-rw-r--r-- 1 root root 1702 Oct 24 2024 tox.ini\n" } ] }, { "role": "assistant", "content": "THOUGHT: This appears to be the Django repository. The issue is related to Django's Case and Q objects, which are likely in the django directory. Let me explore the django directory structure to find the relevant files for database queries and expressions.\n\n```bash\nls -la django/\n```" }, { "role": "user", "content": [ { "type": "text", "text": "0\n\ntotal 88\ndrwxrwxrwx 18 root root 4096 Oct 24 2024 .\ndrwxrwxrwx 1 root root 4096 Oct 24 2024 ..\n-rw-r--r-- 1 root root 799 Oct 24 2024 __init__.py\n-rw-r--r-- 1 root root 211 Oct 24 2024 __main__.py\ndrwxr-xr-x 2 root root 4096 Oct 24 2024 __pycache__\ndrwxrwxrwx 2 root root 4096 Oct 24 2024 apps\ndrwxrwxrwx 6 root root 4096 Oct 24 2024 conf\ndrwxrwxrwx 17 root root 4096 Oct 24 2024 contrib\ndrwxrwxrwx 10 root root 4096 Oct 24 2024 core\ndrwxrwxrwx 5 root root 4096 Oct 24 2024 db\ndrwxrwxrwx 2 root root 4096 Oct 24 2024 dispatch\ndrwxrwxrwx 4 root root 4096 Oct 24 2024 forms\ndrwxrwxrwx 2 root root 4096 Oct 24 2024 http\ndrwxrwxrwx 2 root root 4096 Oct 24 2024 middleware\n-rw-r--r-- 1 root root 5009 Oct 24 2024 shortcuts.py\ndrwxrwxrwx 4 root root 4096 Oct 24 2024 template\ndrwxrwxrwx 2 root root 4096 Oct 24 2024 templatetags\ndrwxrwxrwx 2 root root 4096 Oct 24 2024 test\ndrwxrwxrwx 2 root root 4096 Oct 24 2024 urls\ndrwxrwxrwx 4 root root 4096 Oct 24 2024 utils\ndrwxrwxrwx 5 root root 4096 Oct 24 2024 views\n" } ] }, { "role": "assistant", "content": "THOUGHT: The issue is related to database queries, so I should look in the `django/db` directory. The Case and Q objects are likely in the models or expressions modules within the db package.\n\n```bash\nls -la django/db/\n```" }, { "role": "user", "content": [ { "type": "text", "text": "0\n\ntotal 52\ndrwxrwxrwx 5 root root 4096 Oct 24 2024 .\ndrwxrwxrwx 18 root root 4096 Oct 24 2024 ..\n-rw-r--r-- 1 root root 1483 Oct 24 2024 __init__.py\ndrwxrwxrwx 8 root root 4096 Oct 24 2024 backends\ndrwxrwxrwx 3 root root 4096 Oct 24 2024 migrations\ndrwxrwxrwx 5 root root 4096 Oct 24 2024 models\n-rw-r--r-- 1 root root 12433 Oct 24 2024 transaction.py\n-rw-r--r-- 1 root root 9279 Oct 24 2024 utils.py\n" } ] }, { "role": "assistant", "content": "THOUGHT: The Case and Q objects are likely in the models directory. Let me explore the models directory to find the relevant files.\n\n```bash\nls -la django/db/models/\n```" }, { "role": "user", "content": [ { "type": "text", "text": "0\n\ntotal 456\ndrwxrwxrwx 5 root root 4096 Oct 24 2024 .\ndrwxrwxrwx 5 root root 4096 Oct 24 2024 ..\n-rw-r--r-- 1 root root 2774 Oct 24 2024 __init__.py\n-rw-r--r-- 1 root root 6944 Oct 24 2024 aggregates.py\n-rw-r--r-- 1 root root 99323 Oct 24 2024 base.py\n-rw-r--r-- 1 root root 209 Oct 24 2024 constants.py\n-rw-r--r-- 1 root root 15157 Oct 24 2024 constraints.py\n-rw-r--r-- 1 root root 20758 Oct 24 2024 deletion.py\n-rw-r--r-- 1 root root 2804 Oct 24 2024 enums.py\n-rw-r--r-- 1 root root 62628 Oct 24 2024 expressions.py\ndrwxrwxrwx 2 root root 4096 Oct 24 2024 fields\ndrwxrwxrwx 2 root root 4096 Oct 24 2024 functions\n-rw-r--r-- 1 root root 11871 Oct 24 2024 indexes.py\n-rw-r--r-- 1 root root 24634 Oct 24 2024 lookups.py\n-rw-r--r-- 1 root root 6866 Oct 24 2024 manager.py\n-rw-r--r-- 1 root root 38440 Oct 24 2024 options.py\n-rw-r--r-- 1 root root 101539 Oct 24 2024 query.py\n-rw-r--r-- 1 root root 13185 Oct 24 2024 query_utils.py\n-rw-r--r-- 1 root root 1622 Oct 24 2024 signals.py\ndrwxrwxrwx 2 root root 4096 Oct 24 2024 sql\n-rw-r--r-- 1 root root 1608 Oct 24 2024 utils.py\n" } ] }, { "role": "assistant", "content": "THOUGHT: The Case expression is likely in the `expressions.py` file, and the Q object is probably in `query_utils.py`. Let me first look at the expressions.py file to understand how Case is implemented and where the issue might be.\n\n```bash\ngrep -n \"class Case\" django/db/models/expressions.py\n```" }, { "role": "user", "content": [ { "type": "text", "text": "0\n\n1319:class Case(SQLiteNumericMixin, Expression):\n" } ] }, { "role": "assistant", "content": "THOUGHT: Found the Case class at line 1319. Let me examine the Case class implementation to understand how it handles the When conditions and generates SQL.\n\n```bash\nnl -ba django/db/models/expressions.py | sed -n '1319,1400p'\n```" }, { "role": "user", "content": [ { "type": "text", "text": "0\n\n 1319\tclass Case(SQLiteNumericMixin, Expression):\n 1320\t \"\"\"\n 1321\t An SQL searched CASE expression:\n 1322\t\n 1323\t CASE\n 1324\t WHEN n > 0\n 1325\t THEN 'positive'\n 1326\t WHEN n < 0\n 1327\t THEN 'negative'\n 1328\t ELSE 'zero'\n 1329\t END\n 1330\t \"\"\"\n 1331\t\n 1332\t template = \"CASE %(cases)s ELSE %(default)s END\"\n 1333\t case_joiner = \" \"\n 1334\t\n 1335\t def __init__(self, *cases, default=None, output_field=None, **extra):\n 1336\t if not all(isinstance(case, When) for case in cases):\n 1337\t raise TypeError(\"Positional arguments must all be When objects.\")\n 1338\t super().__init__(output_field)\n 1339\t self.cases = list(cases)\n 1340\t self.default = self._parse_expressions(default)[0]\n 1341\t self.extra = extra\n 1342\t\n 1343\t def __str__(self):\n 1344\t return \"CASE %s, ELSE %r\" % (\n 1345\t \", \".join(str(c) for c in self.cases),\n 1346\t self.default,\n 1347\t )\n 1348\t\n 1349\t def __repr__(self):\n 1350\t return \"<%s: %s>\" % (self.__class__.__name__, self)\n 1351\t\n 1352\t def get_source_expressions(self):\n 1353\t return self.cases + [self.default]\n 1354\t\n 1355\t def set_source_expressions(self, exprs):\n 1356\t *self.cases, self.default = exprs\n 1357\t\n 1358\t def resolve_expression(\n 1359\t self, query=None, allow_joins=True, reuse=None, summarize=False, for_save=False\n 1360\t ):\n 1361\t c = self.copy()\n 1362\t c.is_summary = summarize\n 1363\t for pos, case in enumerate(c.cases):\n 1364\t c.cases[pos] = case.resolve_expression(\n 1365\t query, allow_joins, reuse, summarize, for_save\n 1366\t )\n 1367\t c.default = c.default.resolve_expression(\n 1368\t query, allow_joins, reuse, summarize, for_save\n 1369\t )\n 1370\t return c\n 1371\t\n 1372\t def copy(self):\n 1373\t c = super().copy()\n 1374\t c.cases = c.cases[:]\n 1375\t return c\n 1376\t\n 1377\t def as_sql(\n 1378\t self, compiler, connection, template=None, case_joiner=None, **extra_context\n 1379\t ):\n 1380\t connection.ops.check_expression_support(self)\n 1381\t if not self.cases:\n 1382\t return compiler.compile(self.default)\n 1383\t template_params = {**self.extra, **extra_context}\n 1384\t case_parts = []\n 1385\t sql_params = []\n 1386\t for case in self.cases:\n 1387\t try:\n 1388\t case_sql, case_params = compiler.compile(case)\n 1389\t except EmptyResultSet:\n 1390\t continue\n 1391\t case_parts.append(case_sql)\n 1392\t sql_params.extend(case_params)\n 1393\t default_sql, default_params = compiler.compile(self.default)\n 1394\t if not case_parts:\n 1395\t return default_sql, default_params\n 1396\t case_joiner = case_joiner or self.case_joiner\n 1397\t template_params[\"cases\"] = case_joiner.join(case_parts)\n 1398\t template_params[\"default\"] = default_sql\n 1399\t sql_params.extend(default_params)\n 1400\t template = template or template_params.get(\"template\", self.template)\n" } ] }, { "role": "assistant", "content": "THOUGHT: I can see the issue! In the `as_sql` method, when a `When` case raises an `EmptyResultSet` exception (line 1389), it continues to the next case (line 1390). However, if all cases result in `EmptyResultSet`, then `case_parts` becomes empty, and the method returns just the default value (lines 1394-1395). But the problem is that when `~Q(pk__in=[])` is used, it should match all rows, not result in an empty set.\n\nLet me look at the When class to understand how it handles the condition:\n\n```bash\ngrep -n \"class When\" django/db/models/expressions.py\n```" }, { "role": "user", "content": [ { "type": "text", "text": "0\n\n1245:class When(Expression):\n" } ] }, { "role": "assistant", "content": "THOUGHT: Let me examine the When class implementation to understand how it processes the condition and generates SQL.\n\n```bash\nnl -ba django/db/models/expressions.py | sed -n '1245,1318p'\n```" }, { "role": "user", "content": [ { "type": "text", "text": "0\n\n 1245\tclass When(Expression):\n 1246\t template = \"WHEN %(condition)s THEN %(result)s\"\n 1247\t # This isn't a complete conditional expression, must be used in Case().\n 1248\t conditional = False\n 1249\t\n 1250\t def __init__(self, condition=None, then=None, **lookups):\n 1251\t if lookups:\n 1252\t if condition is None:\n 1253\t condition, lookups = Q(**lookups), None\n 1254\t elif getattr(condition, \"conditional\", False):\n 1255\t condition, lookups = Q(condition, **lookups), None\n 1256\t if condition is None or not getattr(condition, \"conditional\", False) or lookups:\n 1257\t raise TypeError(\n 1258\t \"When() supports a Q object, a boolean expression, or lookups \"\n 1259\t \"as a condition.\"\n 1260\t )\n 1261\t if isinstance(condition, Q) and not condition:\n 1262\t raise ValueError(\"An empty Q() can't be used as a When() condition.\")\n 1263\t super().__init__(output_field=None)\n 1264\t self.condition = condition\n 1265\t self.result = self._parse_expressions(then)[0]\n 1266\t\n 1267\t def __str__(self):\n 1268\t return \"WHEN %r THEN %r\" % (self.condition, self.result)\n 1269\t\n 1270\t def __repr__(self):\n 1271\t return \"<%s: %s>\" % (self.__class__.__name__, self)\n 1272\t\n 1273\t def get_source_expressions(self):\n 1274\t return [self.condition, self.result]\n 1275\t\n 1276\t def set_source_expressions(self, exprs):\n 1277\t self.condition, self.result = exprs\n 1278\t\n 1279\t def get_source_fields(self):\n 1280\t # We're only interested in the fields of the result expressions.\n 1281\t return [self.result._output_field_or_none]\n 1282\t\n 1283\t def resolve_expression(\n 1284\t self, query=None, allow_joins=True, reuse=None, summarize=False, for_save=False\n 1285\t ):\n 1286\t c = self.copy()\n 1287\t c.is_summary = summarize\n 1288\t if hasattr(c.condition, \"resolve_expression\"):\n 1289\t c.condition = c.condition.resolve_expression(\n 1290\t query, allow_joins, reuse, summarize, False\n 1291\t )\n 1292\t c.result = c.result.resolve_expression(\n 1293\t query, allow_joins, reuse, summarize, for_save\n 1294\t )\n 1295\t return c\n 1296\t\n 1297\t def as_sql(self, compiler, connection, template=None, **extra_context):\n 1298\t connection.ops.check_expression_support(self)\n 1299\t template_params = extra_context\n 1300\t sql_params = []\n 1301\t condition_sql, condition_params = compiler.compile(self.condition)\n 1302\t template_params[\"condition\"] = condition_sql\n 1303\t sql_params.extend(condition_params)\n 1304\t result_sql, result_params = compiler.compile(self.result)\n 1305\t template_params[\"result\"] = result_sql\n 1306\t sql_params.extend(result_params)\n 1307\t template = template or self.template\n 1308\t return template % template_params, sql_params\n 1309\t\n 1310\t def get_group_by_cols(self, alias=None):\n 1311\t # This is not a complete expression and cannot be used in GROUP BY.\n 1312\t cols = []\n 1313\t for source in self.get_source_expressions():\n 1314\t cols.extend(source.get_group_by_cols())\n 1315\t return cols\n 1316\t\n 1317\t\n 1318\t@deconstructible(path=\"django.db.models.Case\")\n" } ] }, { "role": "assistant", "content": "THOUGHT: Now I need to understand how Q objects work and specifically what happens with `~Q(pk__in=[])`. Let me look at the Q class implementation in query_utils.py.\n\n```bash\ngrep -n \"class Q\" django/db/models/query_utils.py\n```" }, { "role": "user", "content": [ { "type": "text", "text": "0\n\n35:class Q(tree.Node):\n" } ] }, { "role": "assistant", "content": "THOUGHT: Let me examine the Q class implementation to understand how it handles empty conditions and negation.\n\n```bash\nnl -ba django/db/models/query_utils.py | sed -n '35,100p'\n```" }, { "role": "user", "content": [ { "type": "text", "text": "0\n\n 35\tclass Q(tree.Node):\n 36\t \"\"\"\n 37\t Encapsulate filters as objects that can then be combined logically (using\n 38\t `&` and `|`).\n 39\t \"\"\"\n 40\t\n 41\t # Connection types\n 42\t AND = \"AND\"\n 43\t OR = \"OR\"\n 44\t XOR = \"XOR\"\n 45\t default = AND\n 46\t conditional = True\n 47\t\n 48\t def __init__(self, *args, _connector=None, _negated=False, **kwargs):\n 49\t super().__init__(\n 50\t children=[*args, *sorted(kwargs.items())],\n 51\t connector=_connector,\n 52\t negated=_negated,\n 53\t )\n 54\t\n 55\t def _combine(self, other, conn):\n 56\t if getattr(other, \"conditional\", False) is False:\n 57\t raise TypeError(other)\n 58\t if not self:\n 59\t return other.copy()\n 60\t if not other and isinstance(other, Q):\n 61\t return self.copy()\n 62\t\n 63\t obj = self.create(connector=conn)\n 64\t obj.add(self, conn)\n 65\t obj.add(other, conn)\n 66\t return obj\n 67\t\n 68\t def __or__(self, other):\n 69\t return self._combine(other, self.OR)\n 70\t\n 71\t def __and__(self, other):\n 72\t return self._combine(other, self.AND)\n 73\t\n 74\t def __xor__(self, other):\n 75\t return self._combine(other, self.XOR)\n 76\t\n 77\t def __invert__(self):\n 78\t obj = self.copy()\n 79\t obj.negate()\n 80\t return obj\n 81\t\n 82\t def resolve_expression(\n 83\t self, query=None, allow_joins=True, reuse=None, summarize=False, for_save=False\n 84\t ):\n 85\t # We must promote any new joins to left outer joins so that when Q is\n 86\t # used as an expression, rows aren't filtered due to joins.\n 87\t clause, joins = query._add_q(\n 88\t self,\n 89\t reuse,\n 90\t allow_joins=allow_joins,\n 91\t split_subq=False,\n 92\t check_filterable=False,\n 93\t )\n 94\t query.promote_joins(joins)\n 95\t return clause\n 96\t\n 97\t def flatten(self):\n 98\t \"\"\"\n 99\t Recursively yield this Q object and all subexpressions, in depth-first\n 100\t order.\n" } ] }, { "role": "assistant", "content": "THOUGHT: I need to understand what happens when Q(pk__in=[]) is created and then negated. Let me create a simple reproduction script to see the exact issue and understand the SQL generation process.\n\n```bash\ncat <<'EOF' > reproduce_issue.py\nimport os\nimport django\nfrom django.conf import settings\n\n# Configure Django settings\nsettings.configure(\n DEBUG=True,\n DATABASES={\n 'default': {\n 'ENGINE': 'django.db.backends.sqlite3',\n 'NAME': ':memory:',\n }\n },\n INSTALLED_APPS=[\n 'django.contrib.contenttypes',\n 'django.contrib.auth',\n ],\n USE_TZ=True,\n)\n\ndjango.setup()\n\nfrom django.db import models\nfrom django.db.models import Case, When, Q, Value, BooleanField\nfrom django.contrib.auth.models import User\n\n# Create the database tables\nfrom django.core.management import execute_from_command_line\nexecute_from_command_line(['manage.py', 'migrate', '--run-syncdb'])\n\n# Test the issue\ntry:\n queryset = User.objects.annotate(\n _a=Case(\n When(~Q(pk__in=[]), then=Value(True)),\n default=Value(False),\n output_field=BooleanField(),\n )\n ).order_by(\"-_a\").values(\"pk\")\n \n print(\"SQL Query:\", queryset.query)\n print(\"Results:\", list(queryset))\nexcept Exception as e:\n print(\"Error:\", e)\n print(\"Error type:\", type(e))\n \n# Let's also test what Q(pk__in=[]) and ~Q(pk__in=[]) look like\nprint(\"\\nTesting Q objects:\")\nq_empty = Q(pk__in=[])\nq_negated = ~Q(pk__in=[])\nprint(\"Q(pk__in=[]):\", q_empty)\nprint(\"~Q(pk__in=[]):\", q_negated)\nprint(\"Q(pk__in=[]) is empty:\", not q_empty)\nprint(\"~Q(pk__in=[]) is empty:\", not q_negated)\nEOF\n```" }, { "role": "user", "content": [ { "type": "text", "text": "0\n\n" } ] }, { "role": "assistant", "content": "THOUGHT: Now let me run the reproduction script to see the exact error and understand what's happening.\n\n```bash\npython reproduce_issue.py\n```" }, { "role": "user", "content": [ { "type": "text", "text": "0\n\nOperations to perform:\n Apply all migrations: auth, contenttypes\nRunning migrations:\n Applying contenttypes.0001_initial... OK\n Applying contenttypes.0002_remove_content_type_name... OK\n Applying auth.0001_initial... OK\n Applying auth.0002_alter_permission_name_max_length... OK\n Applying auth.0003_alter_user_email_max_length... OK\n Applying auth.0004_alter_user_username_opts... OK\n Applying auth.0005_alter_user_last_login_null... OK\n Applying auth.0006_require_contenttypes_0002... OK\n Applying auth.0007_alter_validators_add_error_messages... OK\n Applying auth.0008_alter_user_username_max_length... OK\n Applying auth.0009_alter_user_last_name_max_length... OK\n Applying auth.0010_alter_group_name_max_length... OK\n Applying auth.0011_update_proxy_permissions... OK\n Applying auth.0012_alter_user_first_name_max_length... OK\nSQL Query: SELECT \"auth_user\".\"id\" FROM \"auth_user\" ORDER BY CASE WHEN THEN True ELSE False END DESC\nError: near \"THEN\": syntax error\nError type: \n\nTesting Q objects:\nQ(pk__in=[]): (AND: ('pk__in', []))\n~Q(pk__in=[]): (NOT (AND: ('pk__in', [])))\nQ(pk__in=[]) is empty: False\n~Q(pk__in=[]) is empty: False\n" } ] }, { "role": "assistant", "content": "THOUGHT: Perfect! I can see the issue clearly now. The SQL query shows `CASE WHEN THEN True ELSE False END` - there's no condition between WHEN and THEN, which causes the syntax error. The problem is that when `~Q(pk__in=[])` is compiled, it results in an empty condition string.\n\nLet me examine how Q objects are compiled to SQL to understand where the empty condition comes from. I need to look at the query compilation process.\n\n```bash\nfind django -name \"*.py\" -exec grep -l \"compile.*Q\\|_add_q\" {} \\; | head -5\n```" }, { "role": "user", "content": [ { "type": "text", "text": "0\n\ndjango/db/backends/sqlite3/operations.py\ndjango/db/backends/mysql/compiler.py\ndjango/db/backends/base/schema.py\ndjango/db/models/query_utils.py\ndjango/db/models/fields/related_lookups.py\nfind: 'grep' terminated by signal 13\nfind: 'grep' terminated by signal 13\nfind: 'grep' terminated by signal 13\nfind: 'grep' terminated by signal 13\n" } ] }, { "role": "assistant", "content": "THOUGHT: Let me look at the SQL compilation process. The issue is likely in how empty Q objects are handled during SQL compilation. Let me check the sql directory in the models package.\n\n```bash\nls -la django/db/models/sql/\n```" }, { "role": "user", "content": [ { "type": "text", "text": "0\n\ntotal 248\ndrwxrwxrwx 1 root root 4096 Jul 22 03:12 .\ndrwxrwxrwx 1 root root 4096 Jul 22 03:12 ..\n-rw-r--r-- 1 root root 241 Oct 24 2024 __init__.py\ndrwxr-xr-x 2 root root 4096 Jul 22 03:12 __pycache__\n-rw-r--r-- 1 root root 81934 Oct 24 2024 compiler.py\n-rw-r--r-- 1 root root 533 Oct 24 2024 constants.py\n-rw-r--r-- 1 root root 7180 Oct 24 2024 datastructures.py\n-rw-r--r-- 1 root root 114621 Oct 24 2024 query.py\n-rw-r--r-- 1 root root 5935 Oct 24 2024 subqueries.py\n-rw-r--r-- 1 root root 9969 Oct 24 2024 where.py\n" } ] }, { "role": "assistant", "content": "THOUGHT: Let me look at the where.py file since that's likely where Q objects are compiled to SQL conditions.\n\n```bash\ngrep -n \"class.*Where\\|def.*compile\\|EmptyResultSet\" django/db/models/sql/where.py\n```" }, { "role": "user", "content": [ { "type": "text", "text": "0\n\n7:from django.core.exceptions import EmptyResultSet\n19:class WhereNode(tree.Node):\n81: def as_sql(self, compiler, connection):\n85: None, [] if this node is empty, and raise EmptyResultSet if this\n113: except EmptyResultSet:\n130: raise EmptyResultSet\n133: raise EmptyResultSet\n234: def select_format(self, compiler, sql, params):\n254: def as_sql(self, compiler=None, connection=None):\n255: raise EmptyResultSet\n258:class ExtraWhere:\n266: def as_sql(self, compiler=None, connection=None):\n283: def as_sql(self, compiler, connection):\n" } ] }, { "role": "assistant", "content": "THOUGHT: Let me examine the WhereNode.as_sql method to understand how it handles empty conditions and when it raises EmptyResultSet.\n\n```bash\nnl -ba django/db/models/sql/where.py | sed -n '81,140p'\n```" }, { "role": "user", "content": [ { "type": "text", "text": "0\n\n 81\t def as_sql(self, compiler, connection):\n 82\t \"\"\"\n 83\t Return the SQL version of the where clause and the value to be\n 84\t substituted in. Return '', [] if this node matches everything,\n 85\t None, [] if this node is empty, and raise EmptyResultSet if this\n 86\t node can't match anything.\n 87\t \"\"\"\n 88\t result = []\n 89\t result_params = []\n 90\t if self.connector == AND:\n 91\t full_needed, empty_needed = len(self.children), 1\n 92\t else:\n 93\t full_needed, empty_needed = 1, len(self.children)\n 94\t\n 95\t if self.connector == XOR and not connection.features.supports_logical_xor:\n 96\t # Convert if the database doesn't support XOR:\n 97\t # a XOR b XOR c XOR ...\n 98\t # to:\n 99\t # (a OR b OR c OR ...) AND (a + b + c + ...) == 1\n 100\t lhs = self.__class__(self.children, OR)\n 101\t rhs_sum = reduce(\n 102\t operator.add,\n 103\t (Case(When(c, then=1), default=0) for c in self.children),\n 104\t )\n 105\t rhs = Exact(1, rhs_sum)\n 106\t return self.__class__([lhs, rhs], AND, self.negated).as_sql(\n 107\t compiler, connection\n 108\t )\n 109\t\n 110\t for child in self.children:\n 111\t try:\n 112\t sql, params = compiler.compile(child)\n 113\t except EmptyResultSet:\n 114\t empty_needed -= 1\n 115\t else:\n 116\t if sql:\n 117\t result.append(sql)\n 118\t result_params.extend(params)\n 119\t else:\n 120\t full_needed -= 1\n 121\t # Check if this node matches nothing or everything.\n 122\t # First check the amount of full nodes and empty nodes\n 123\t # to make this node empty/full.\n 124\t # Now, check if this node is full/empty using the\n 125\t # counts.\n 126\t if empty_needed == 0:\n 127\t if self.negated:\n 128\t return \"\", []\n 129\t else:\n 130\t raise EmptyResultSet\n 131\t if full_needed == 0:\n 132\t if self.negated:\n 133\t raise EmptyResultSet\n 134\t else:\n 135\t return \"\", []\n 136\t conn = \" %s \" % self.connector\n 137\t sql_string = conn.join(result)\n 138\t if sql_string:\n 139\t if self.negated:\n 140\t # Some backends (Oracle at least) need parentheses\n" } ] }, { "role": "assistant", "content": "THOUGHT: Now I understand the issue! When `Q(pk__in=[])` is compiled, it likely raises `EmptyResultSet` because an empty `__in` lookup matches nothing. When this is negated with `~`, the negated empty condition should match everything and return an empty string `\"\"` (line 128). However, when this empty string is used in the When condition, it creates invalid SQL.\n\nLet me look at how the `__in` lookup is handled when the list is empty:\n\n```bash\ngrep -n \"class.*In\\|EmptyResultSet\" django/db/models/lookups.py\n```" }, { "role": "user", "content": [ { "type": "text", "text": "0\n\n4:from django.core.exceptions import EmptyResultSet\n392:class IntegerFieldFloatRounding:\n405:class IntegerGreaterThanOrEqual(IntegerFieldFloatRounding, GreaterThanOrEqual):\n410:class IntegerLessThan(IntegerFieldFloatRounding, LessThan):\n415:class In(FieldGetDbPrepValueIterableMixin, BuiltinLookup):\n445: raise EmptyResultSet\n" } ] }, { "role": "assistant", "content": "THOUGHT: Perfect! Let me examine the In lookup class to see how it handles empty lists.\n\n```bash\nnl -ba django/db/models/lookups.py | sed -n '415,460p'\n```" }, { "role": "user", "content": [ { "type": "text", "text": "0\n\n 415\tclass In(FieldGetDbPrepValueIterableMixin, BuiltinLookup):\n 416\t lookup_name = \"in\"\n 417\t\n 418\t def get_prep_lookup(self):\n 419\t from django.db.models.sql.query import Query # avoid circular import\n 420\t\n 421\t if isinstance(self.rhs, Query):\n 422\t self.rhs.clear_ordering(clear_default=True)\n 423\t if not self.rhs.has_select_fields:\n 424\t self.rhs.clear_select_clause()\n 425\t self.rhs.add_fields([\"pk\"])\n 426\t return super().get_prep_lookup()\n 427\t\n 428\t def process_rhs(self, compiler, connection):\n 429\t db_rhs = getattr(self.rhs, \"_db\", None)\n 430\t if db_rhs is not None and db_rhs != connection.alias:\n 431\t raise ValueError(\n 432\t \"Subqueries aren't allowed across different databases. Force \"\n 433\t \"the inner query to be evaluated using `list(inner_query)`.\"\n 434\t )\n 435\t\n 436\t if self.rhs_is_direct_value():\n 437\t # Remove None from the list as NULL is never equal to anything.\n 438\t try:\n 439\t rhs = OrderedSet(self.rhs)\n 440\t rhs.discard(None)\n 441\t except TypeError: # Unhashable items in self.rhs\n 442\t rhs = [r for r in self.rhs if r is not None]\n 443\t\n 444\t if not rhs:\n 445\t raise EmptyResultSet\n 446\t\n 447\t # rhs should be an iterable; use batch_process_rhs() to\n 448\t # prepare/transform those values.\n 449\t sqls, sqls_params = self.batch_process_rhs(compiler, connection, rhs)\n 450\t placeholder = \"(\" + \", \".join(sqls) + \")\"\n 451\t return (placeholder, sqls_params)\n 452\t return super().process_rhs(compiler, connection)\n 453\t\n 454\t def get_rhs_op(self, connection, rhs):\n 455\t return \"IN %s\" % rhs\n 456\t\n 457\t def as_sql(self, compiler, connection):\n 458\t max_in_list_size = connection.ops.max_in_list_size()\n 459\t if (\n 460\t self.rhs_is_direct_value()\n" } ] }, { "role": "assistant", "content": "THOUGHT: Excellent! Now I can see the exact issue. At line 444-445, when `rhs` (the right-hand side of the `__in` lookup) is empty, it raises `EmptyResultSet`. This means `Q(pk__in=[])` raises `EmptyResultSet`, and when negated with `~`, it should match everything.\n\nThe problem is in the When.as_sql method. When the condition compiles to an empty string (which means \"match everything\"), the SQL becomes invalid. Let me look at the When.as_sql method again and see how to fix it.\n\nLooking back at the When.as_sql method (lines 1297-1308), the issue is at line 1301 where `compiler.compile(self.condition)` returns an empty string for conditions that match everything, but the template still tries to use it.\n\nThe fix should be in the When.as_sql method to handle the case where the condition is empty (matches everything). Let me implement the fix:\n\n```bash\ncp django/db/models/expressions.py django/db/models/expressions.py.backup\n```" }, { "role": "user", "content": [ { "type": "text", "text": "0\n\n" } ] }, { "role": "assistant", "content": "THOUGHT: Now I'll modify the When.as_sql method to handle the case where the condition compiles to an empty string (which means it matches everything). In this case, we should return just the result without the WHEN/THEN structure.\n\n```bash\nsed -i '1297,1308c\\\n def as_sql(self, compiler, connection, template=None, **extra_context):\\\n connection.ops.check_expression_support(self)\\\n template_params = extra_context\\\n sql_params = []\\\n condition_sql, condition_params = compiler.compile(self.condition)\\\n # If condition is empty (matches everything), just return the result\\\n if not condition_sql:\\\n return compiler.compile(self.result)\\\n template_params[\"condition\"] = condition_sql\\\n sql_params.extend(condition_params)\\\n result_sql, result_params = compiler.compile(self.result)\\\n template_params[\"result\"] = result_sql\\\n sql_params.extend(result_params)\\\n template = template or self.template\\\n return template % template_params, sql_params' django/db/models/expressions.py\n```" }, { "role": "user", "content": [ { "type": "text", "text": "0\n\n" } ] }, { "role": "assistant", "content": "THOUGHT: Let me verify that the change was applied correctly by checking the modified When.as_sql method:\n\n```bash\nnl -ba django/db/models/expressions.py | sed -n '1297,1315p'\n```" }, { "role": "user", "content": [ { "type": "text", "text": "0\n\n 1297\t def as_sql(self, compiler, connection, template=None, **extra_context):\n 1298\t connection.ops.check_expression_support(self)\n 1299\t template_params = extra_context\n 1300\t sql_params = []\n 1301\t condition_sql, condition_params = compiler.compile(self.condition)\n 1302\t # If condition is empty (matches everything), just return the result\n 1303\t if not condition_sql:\n 1304\t return compiler.compile(self.result)\n 1305\t template_params[\"condition\"] = condition_sql\n 1306\t sql_params.extend(condition_params)\n 1307\t result_sql, result_params = compiler.compile(self.result)\n 1308\t template_params[\"result\"] = result_sql\n 1309\t sql_params.extend(result_params)\n 1310\t template = template or self.template\n 1311\t return template % template_params, sql_params\n 1312\t\n 1313\t def get_group_by_cols(self, alias=None):\n 1314\t # This is not a complete expression and cannot be used in GROUP BY.\n 1315\t cols = []\n" } ] }, { "role": "assistant", "content": "THOUGHT: Good! The change looks correct. Now let me test the fix by running the reproduction script again to see if it resolves the issue.\n\n```bash\npython reproduce_issue.py\n```" }, { "role": "user", "content": [ { "type": "text", "text": "0\n\nOperations to perform:\n Apply all migrations: auth, contenttypes\nRunning migrations:\n Applying contenttypes.0001_initial... OK\n Applying contenttypes.0002_remove_content_type_name... OK\n Applying auth.0001_initial... OK\n Applying auth.0002_alter_permission_name_max_length... OK\n Applying auth.0003_alter_user_email_max_length... OK\n Applying auth.0004_alter_user_username_opts... OK\n Applying auth.0005_alter_user_last_login_null... OK\n Applying auth.0006_require_contenttypes_0002... OK\n Applying auth.0007_alter_validators_add_error_messages... OK\n Applying auth.0008_alter_user_username_max_length... OK\n Applying auth.0009_alter_user_last_name_max_length... OK\n Applying auth.0010_alter_group_name_max_length... OK\n Applying auth.0011_update_proxy_permissions... OK\n Applying auth.0012_alter_user_first_name_max_length... OK\nSQL Query: SELECT \"auth_user\".\"id\" FROM \"auth_user\" ORDER BY CASE True ELSE False END DESC\nError: near \"ELSE\": syntax error\nError type: \n\nTesting Q objects:\nQ(pk__in=[]): (AND: ('pk__in', []))\n~Q(pk__in=[]): (NOT (AND: ('pk__in', [])))\nQ(pk__in=[]) is empty: False\n~Q(pk__in=[]) is empty: False\n" } ] }, { "role": "assistant", "content": "THOUGHT: I see there's still an issue. The SQL now shows `CASE True ELSE False END` instead of `CASE WHEN THEN True ELSE False END`, which means my fix worked for the When clause, but now the Case clause has an issue. When all When conditions match everything (return just their results), the Case.as_sql method needs to handle this properly.\n\nLet me look at the Case.as_sql method again and see how to fix it:\n\n```bash\nnl -ba django/db/models/expressions.py | sed -n '1377,1405p'\n```" }, { "role": "user", "content": [ { "type": "text", "text": "0\n\n 1377\t c.cases = c.cases[:]\n 1378\t return c\n 1379\t\n 1380\t def as_sql(\n 1381\t self, compiler, connection, template=None, case_joiner=None, **extra_context\n 1382\t ):\n 1383\t connection.ops.check_expression_support(self)\n 1384\t if not self.cases:\n 1385\t return compiler.compile(self.default)\n 1386\t template_params = {**self.extra, **extra_context}\n 1387\t case_parts = []\n 1388\t sql_params = []\n 1389\t for case in self.cases:\n 1390\t try:\n 1391\t case_sql, case_params = compiler.compile(case)\n 1392\t except EmptyResultSet:\n 1393\t continue\n 1394\t case_parts.append(case_sql)\n 1395\t sql_params.extend(case_params)\n 1396\t default_sql, default_params = compiler.compile(self.default)\n 1397\t if not case_parts:\n 1398\t return default_sql, default_params\n 1399\t case_joiner = case_joiner or self.case_joiner\n 1400\t template_params[\"cases\"] = case_joiner.join(case_parts)\n 1401\t template_params[\"default\"] = default_sql\n 1402\t sql_params.extend(default_params)\n 1403\t template = template or template_params.get(\"template\", self.template)\n 1404\t sql = template % template_params\n 1405\t if self._output_field_or_none is not None:\n" } ] }, { "role": "assistant", "content": "THOUGHT: I see the issue now. When a When condition matches everything, my fix makes it return just the result (like \"True\") instead of the full \"WHEN condition THEN result\" structure. But the Case expects all case_parts to be complete WHEN clauses.\n\nI need to reconsider the approach. Instead of making When return just the result when the condition is empty, I should make it return a proper WHEN clause that always matches. Let me revert my change and implement a better solution.\n\n```bash\ncp django/db/models/expressions.py.backup django/db/models/expressions.py\n```" }, { "role": "user", "content": [ { "type": "text", "text": "0\n\n" } ] }, { "role": "assistant", "content": "THOUGHT: Now I need a better approach. The issue is that when `~Q(pk__in=[])` compiles to an empty condition, it creates invalid SQL. Instead of changing When to return just the result, I should make it generate a condition that always evaluates to true when the condition is empty.\n\nLet me modify the When.as_sql method to use \"1=1\" (which always evaluates to true) when the condition is empty:\n\n```bash\nsed -i '1297,1308c\\\n def as_sql(self, compiler, connection, template=None, **extra_context):\\\n connection.ops.check_expression_support(self)\\\n template_params = extra_context\\\n sql_params = []\\\n condition_sql, condition_params = compiler.compile(self.condition)\\\n # If condition is empty (matches everything), use a condition that always evaluates to true\\\n if not condition_sql:\\\n condition_sql = \"1=1\"\\\n condition_params = []\\\n template_params[\"condition\"] = condition_sql\\\n sql_params.extend(condition_params)\\\n result_sql, result_params = compiler.compile(self.result)\\\n template_params[\"result\"] = result_sql\\\n sql_params.extend(result_params)\\\n template = template or self.template\\\n return template % template_params, sql_params' django/db/models/expressions.py\n```" }, { "role": "user", "content": [ { "type": "text", "text": "0\n\n" } ] }, { "role": "assistant", "content": "THOUGHT: Let me verify the change was applied correctly:\n\n```bash\nnl -ba django/db/models/expressions.py | sed -n '1297,1315p'\n```" }, { "role": "user", "content": [ { "type": "text", "text": "0\n\n 1297\t def as_sql(self, compiler, connection, template=None, **extra_context):\n 1298\t connection.ops.check_expression_support(self)\n 1299\t template_params = extra_context\n 1300\t sql_params = []\n 1301\t condition_sql, condition_params = compiler.compile(self.condition)\n 1302\t # If condition is empty (matches everything), use a condition that always evaluates to true\n 1303\t if not condition_sql:\n 1304\t condition_sql = \"1=1\"\n 1305\t condition_params = []\n 1306\t template_params[\"condition\"] = condition_sql\n 1307\t sql_params.extend(condition_params)\n 1308\t result_sql, result_params = compiler.compile(self.result)\n 1309\t template_params[\"result\"] = result_sql\n 1310\t sql_params.extend(result_params)\n 1311\t template = template or self.template\n 1312\t return template % template_params, sql_params\n 1313\t\n 1314\t def get_group_by_cols(self, alias=None):\n 1315\t # This is not a complete expression and cannot be used in GROUP BY.\n" } ] }, { "role": "assistant", "content": "THOUGHT: Perfect! Now let me test the fix again to see if it resolves the issue:\n\n```bash\npython reproduce_issue.py\n```" }, { "role": "user", "content": [ { "type": "text", "text": "0\n\nOperations to perform:\n Apply all migrations: auth, contenttypes\nRunning migrations:\n Applying contenttypes.0001_initial... OK\n Applying contenttypes.0002_remove_content_type_name... OK\n Applying auth.0001_initial... OK\n Applying auth.0002_alter_permission_name_max_length... OK\n Applying auth.0003_alter_user_email_max_length... OK\n Applying auth.0004_alter_user_username_opts... OK\n Applying auth.0005_alter_user_last_login_null... OK\n Applying auth.0006_require_contenttypes_0002... OK\n Applying auth.0007_alter_validators_add_error_messages... OK\n Applying auth.0008_alter_user_username_max_length... OK\n Applying auth.0009_alter_user_last_name_max_length... OK\n Applying auth.0010_alter_group_name_max_length... OK\n Applying auth.0011_update_proxy_permissions... OK\n Applying auth.0012_alter_user_first_name_max_length... OK\nSQL Query: SELECT \"auth_user\".\"id\" FROM \"auth_user\" ORDER BY CASE WHEN 1=1 THEN True ELSE False END DESC\nResults: []\n\nTesting Q objects:\nQ(pk__in=[]): (AND: ('pk__in', []))\n~Q(pk__in=[]): (NOT (AND: ('pk__in', [])))\nQ(pk__in=[]) is empty: False\n~Q(pk__in=[]) is empty: False\n" } ] }, { "role": "assistant", "content": "THOUGHT: Excellent! The fix works! The SQL query now shows `CASE WHEN 1=1 THEN True ELSE False END` which is valid SQL. The query executes successfully and returns an empty result (which is expected since there are no users in the database).\n\nLet me create a more comprehensive test to verify the fix works correctly with actual data:\n\n```bash\ncat <<'EOF' > test_fix.py\nimport os\nimport django\nfrom django.conf import settings\n\n# Configure Django settings\nsettings.configure(\n DEBUG=True,\n DATABASES={\n 'default': {\n 'ENGINE': 'django.db.backends.sqlite3',\n 'NAME': ':memory:',\n }\n },\n INSTALLED_APPS=[\n 'django.contrib.contenttypes',\n 'django.contrib.auth',\n ],\n USE_TZ=True,\n)\n\ndjango.setup()\n\nfrom django.db import models\nfrom django.db.models import Case, When, Q, Value, BooleanField\nfrom django.contrib.auth.models import User\n\n# Create the database tables\nfrom django.core.management import execute_from_command_line\nexecute_from_command_line(['manage.py', 'migrate', '--run-syncdb'])\n\n# Create some test users\nUser.objects.create_user('user1', 'user1@example.com', 'password')\nUser.objects.create_user('user2', 'user2@example.com', 'password')\n\nprint(\"Created users:\", User.objects.count())\n\n# Test the original issue - should work now\ntry:\n queryset = User.objects.annotate(\n _a=Case(\n When(~Q(pk__in=[]), then=Value(True)),\n default=Value(False),\n output_field=BooleanField(),\n )\n ).order_by(\"-_a\").values(\"pk\", \"_a\")\n \n print(\"SQL Query:\", queryset.query)\n results = list(queryset)\n print(\"Results:\", results)\n print(\"All results have _a=True:\", all(r['_a'] for r in results))\nexcept Exception as e:\n print(\"Error:\", e)\n\n# Test edge cases\nprint(\"\\nTesting edge cases:\")\n\n# Test with Q(pk__in=[1, 2]) - should match specific users\ntry:\n queryset = User.objects.annotate(\n _a=Case(\n When(Q(pk__in=[1, 2]), then=Value(True)),\n default=Value(False),\n output_field=BooleanField(),\n )\n ).values(\"pk\", \"_a\")\n \n results = list(queryset)\n print(\"Q(pk__in=[1, 2]) results:\", results)\nexcept Exception as e:\n print(\"Error with Q(pk__in=[1, 2]):\", e)\n\n# Test with ~Q(pk__in=[1]) - should match all except pk=1\ntry:\n queryset = User.objects.annotate(\n _a=Case(\n When(~Q(pk__in=[1]), then=Value(True)),\n default=Value(False),\n output_field=BooleanField(),\n )\n ).values(\"pk\", \"_a\")\n \n results = list(queryset)\n print(\"~Q(pk__in=[1]) results:\", results)\nexcept Exception as e:\n print(\"Error with ~Q(pk__in=[1]):\", e)\nEOF\n```" }, { "role": "user", "content": [ { "type": "text", "text": "0\n\n" } ] }, { "role": "assistant", "content": "THOUGHT: Now let me run the comprehensive test to verify the fix works correctly with actual data and edge cases:\n\n```bash\npython test_fix.py\n```" }, { "role": "user", "content": [ { "type": "text", "text": "0\n\nOperations to perform:\n Apply all migrations: auth, contenttypes\nRunning migrations:\n Applying contenttypes.0001_initial... OK\n Applying contenttypes.0002_remove_content_type_name... OK\n Applying auth.0001_initial... OK\n Applying auth.0002_alter_permission_name_max_length... OK\n Applying auth.0003_alter_user_email_max_length... OK\n Applying auth.0004_alter_user_username_opts... OK\n Applying auth.0005_alter_user_last_login_null... OK\n Applying auth.0006_require_contenttypes_0002... OK\n Applying auth.0007_alter_validators_add_error_messages... OK\n Applying auth.0008_alter_user_username_max_length... OK\n Applying auth.0009_alter_user_last_name_max_length... OK\n Applying auth.0010_alter_group_name_max_length... OK\n Applying auth.0011_update_proxy_permissions... OK\n Applying auth.0012_alter_user_first_name_max_length... OK\nCreated users: 2\nSQL Query: SELECT \"auth_user\".\"id\", CASE WHEN 1=1 THEN True ELSE False END AS \"_a\" FROM \"auth_user\" ORDER BY \"_a\" DESC\nResults: [{'pk': 1, '_a': True}, {'pk': 2, '_a': True}]\nAll results have _a=True: True\n\nTesting edge cases:\nQ(pk__in=[1, 2]) results: [{'pk': 1, '_a': True}, {'pk': 2, '_a': True}]\n~Q(pk__in=[1]) results: [{'pk': 1, '_a': False}, {'pk': 2, '_a': True}]\n" } ] }, { "role": "assistant", "content": "THOUGHT: Perfect! The fix is working correctly. Let me verify the behavior is as expected:\n\n1. `~Q(pk__in=[])` now generates `CASE WHEN 1=1 THEN True ELSE False END` which correctly evaluates to True for all rows\n2. `Q(pk__in=[1, 2])` works correctly and matches the specified PKs\n3. `~Q(pk__in=[1])` works correctly and matches all rows except pk=1\n\nThe fix handles the edge case properly while maintaining compatibility with normal cases. Let me also test one more edge case to make sure the fix doesn't break anything else:\n\n```bash\ncat <<'EOF' > test_additional_cases.py\nimport os\nimport django\nfrom django.conf import settings\n\nsettings.configure(\n DEBUG=True,\n DATABASES={\n 'default': {\n 'ENGINE': 'django.db.backends.sqlite3',\n 'NAME': ':memory:',\n }\n },\n INSTALLED_APPS=[\n 'django.contrib.contenttypes',\n 'django.contrib.auth',\n ],\n USE_TZ=True,\n)\n\ndjango.setup()\n\nfrom django.db import models\nfrom django.db.models import Case, When, Q, Value, BooleanField\nfrom django.contrib.auth.models import User\n\n# Create the database tables\nfrom django.core.management import execute_from_command_line\nexecute_from_command_line(['manage.py', 'migrate', '--run-syncdb'])\n\n# Create test users\nUser.objects.create_user('user1', 'user1@example.com', 'password')\nUser.objects.create_user('user2', 'user2@example.com', 'password')\n\n# Test multiple When clauses with empty conditions\ntry:\n queryset = User.objects.annotate(\n _a=Case(\n When(~Q(pk__in=[]), then=Value('always_true')),\n When(Q(username='user1'), then=Value('user1_match')),\n default=Value('default'),\n output_field=models.CharField(max_length=20),\n )\n ).values(\"pk\", \"username\", \"_a\")\n \n results = list(queryset)\n print(\"Multiple When clauses results:\", results)\n print(\"All results have _a='always_true':\", all(r['_a'] == 'always_true' for r in results))\nexcept Exception as e:\n print(\"Error with multiple When clauses:\", e)\n\n# Test nested Q objects with empty conditions\ntry:\n queryset = User.objects.annotate(\n _a=Case(\n When(Q(username='user1') | ~Q(pk__in=[]), then=Value(True)),\n default=Value(False),\n output_field=BooleanField(),\n )\n ).values(\"pk\", \"username\", \"_a\")\n \n results = list(queryset)\n print(\"Nested Q objects results:\", results)\n print(\"All results have _a=True:\", all(r['_a'] for r in results))\nexcept Exception as e:\n print(\"Error with nested Q objects:\", e)\nEOF\n```" }, { "role": "user", "content": [ { "type": "text", "text": "0\n\n" } ] }, { "role": "assistant", "content": "THOUGHT: Let me run this additional test to ensure the fix works correctly with more complex scenarios:\n\n```bash\npython test_additional_cases.py\n```" }, { "role": "user", "content": [ { "type": "text", "text": "0\n\nOperations to perform:\n Apply all migrations: auth, contenttypes\nRunning migrations:\n Applying contenttypes.0001_initial... OK\n Applying contenttypes.0002_remove_content_type_name... OK\n Applying auth.0001_initial... OK\n Applying auth.0002_alter_permission_name_max_length... OK\n Applying auth.0003_alter_user_email_max_length... OK\n Applying auth.0004_alter_user_username_opts... OK\n Applying auth.0005_alter_user_last_login_null... OK\n Applying auth.0006_require_contenttypes_0002... OK\n Applying auth.0007_alter_validators_add_error_messages... OK\n Applying auth.0008_alter_user_username_max_length... OK\n Applying auth.0009_alter_user_last_name_max_length... OK\n Applying auth.0010_alter_group_name_max_length... OK\n Applying auth.0011_update_proxy_permissions... OK\n Applying auth.0012_alter_user_first_name_max_length... OK\nMultiple When clauses results: [{'pk': 1, 'username': 'user1', '_a': 'always_true'}, {'pk': 2, 'username': 'user2', '_a': 'always_true'}]\nAll results have _a='always_true': True\nNested Q objects results: [{'pk': 1, 'username': 'user1', '_a': True}, {'pk': 2, 'username': 'user2', '_a': True}]\nAll results have _a=True: True\n" } ] }, { "role": "assistant", "content": "THOUGHT: Excellent! The fix works perfectly for all test cases, including complex scenarios with multiple When clauses and nested Q objects. The fix correctly handles the edge case where `~Q(pk__in=[])` should match everything by using `1=1` as the condition.\n\nLet me also test that the fix doesn't break normal Q object behavior by testing a case that should raise EmptyResultSet:\n\n```bash\ncat <<'EOF' > test_empty_result_set.py\nimport os\nimport django\nfrom django.conf import settings\n\nsettings.configure(\n DEBUG=True,\n DATABASES={\n 'default': {\n 'ENGINE': 'django.db.backends.sqlite3',\n 'NAME': ':memory:',\n }\n },\n INSTALLED_APPS=[\n 'django.contrib.contenttypes',\n 'django.contrib.auth',\n ],\n USE_TZ=True,\n)\n\ndjango.setup()\n\nfrom django.db import models\nfrom django.db.models import Case, When, Q, Value, BooleanField\nfrom django.contrib.auth.models import User\n\n# Create the database tables\nfrom django.core.management import execute_from_command_line\nexecute_from_command_line(['manage.py', 'migrate', '--run-syncdb'])\n\n# Create test users\nUser.objects.create_user('user1', 'user1@example.com', 'password')\n\n# Test that Q(pk__in=[]) still behaves correctly (should match nothing)\ntry:\n queryset = User.objects.annotate(\n _a=Case(\n When(Q(pk__in=[]), then=Value(True)), # This should never match\n default=Value(False),\n output_field=BooleanField(),\n )\n ).values(\"pk\", \"_a\")\n \n results = list(queryset)\n print(\"Q(pk__in=[]) results:\", results)\n print(\"All results have _a=False:\", all(not r['_a'] for r in results))\nexcept Exception as e:\n print(\"Error with Q(pk__in=[]):\", e)\n\n# Test that normal conditions still work\ntry:\n queryset = User.objects.annotate(\n _a=Case(\n When(Q(username='user1'), then=Value(True)),\n default=Value(False),\n output_field=BooleanField(),\n )\n ).values(\"pk\", \"username\", \"_a\")\n \n results = list(queryset)\n print(\"Normal Q condition results:\", results)\nexcept Exception as e:\n print(\"Error with normal Q condition:\", e)\nEOF\n```" }, { "role": "user", "content": [ { "type": "text", "text": "0\n\n" } ] }, { "role": "assistant", "content": "THOUGHT: Let me run this test to ensure that normal Q object behavior is preserved:\n\n```bash\npython test_empty_result_set.py\n```" }, { "role": "user", "content": [ { "type": "text", "text": "0\n\nOperations to perform:\n Apply all migrations: auth, contenttypes\nRunning migrations:\n Applying contenttypes.0001_initial... OK\n Applying contenttypes.0002_remove_content_type_name... OK\n Applying auth.0001_initial... OK\n Applying auth.0002_alter_permission_name_max_length... OK\n Applying auth.0003_alter_user_email_max_length... OK\n Applying auth.0004_alter_user_username_opts... OK\n Applying auth.0005_alter_user_last_login_null... OK\n Applying auth.0006_require_contenttypes_0002... OK\n Applying auth.0007_alter_validators_add_error_messages... OK\n Applying auth.0008_alter_user_username_max_length... OK\n Applying auth.0009_alter_user_last_name_max_length... OK\n Applying auth.0010_alter_group_name_max_length... OK\n Applying auth.0011_update_proxy_permissions... OK\n Applying auth.0012_alter_user_first_name_max_length... OK\nQ(pk__in=[]) results: [{'pk': 1, '_a': False}]\nAll results have _a=False: True\nNormal Q condition results: [{'pk': 1, 'username': 'user1', '_a': True}]\n", "cache_control": { "type": "ephemeral" } } ] }, { "role": "assistant", "content": "THOUGHT: Perfect! The fix is working correctly in all scenarios:\n\n1. `~Q(pk__in=[])` now works correctly and matches all rows (the original issue is fixed)\n2. `Q(pk__in=[])` still works correctly and matches no rows (preserves existing behavior)\n3. Normal Q conditions continue to work as expected\n4. Complex scenarios with multiple When clauses and nested Q objects work correctly\n\nThe fix is minimal, targeted, and doesn't break any existing functionality. It specifically addresses the issue where an empty condition (which should match everything) was generating invalid SQL by substituting `1=1` as a condition that always evaluates to true.\n\nLet me clean up the test files and submit the final solution:\n\n```bash\nrm reproduce_issue.py test_fix.py test_additional_cases.py test_empty_result_set.py django/db/models/expressions.py.backup\n```" }, { "role": "user", "content": [ { "type": "text", "text": "0\n\n", "cache_control": { "type": "ephemeral" } } ] }, { "role": "assistant", "content": "THOUGHT: Now I'm ready to submit my final solution. The fix I implemented addresses the issue described in the PR by modifying the `When.as_sql` method in `django/db/models/expressions.py` to handle the case where a condition compiles to an empty string (which means it matches everything). Instead of generating invalid SQL with an empty condition, it now uses `1=1` as a condition that always evaluates to true.\n\n```bash\necho MICRO_SWE_AGENT_FINAL_OUTPUT && git add -A && git diff --cached\n```" }, { "role": "user", "content": "diff --git a/django/db/models/expressions.py b/django/db/models/expressions.py\nindex 822968ef56..02a49836d7 100644\n--- a/django/db/models/expressions.py\n+++ b/django/db/models/expressions.py\n@@ -1299,6 +1299,10 @@ class When(Expression):\n template_params = extra_context\n sql_params = []\n condition_sql, condition_params = compiler.compile(self.condition)\n+ # If condition is empty (matches everything), use a condition that always evaluates to true\n+ if not condition_sql:\n+ condition_sql = \"1=1\"\n+ condition_params = []\n template_params[\"condition\"] = condition_sql\n sql_params.extend(condition_params)\n result_sql, result_params = compiler.compile(self.result)" } ], "instance_id": "django__django-15930" }