feat(django-google-spanner): support Django 6.0

[sakthivelmanii]

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Fixes #<issue_number_goes_here> 🦕

[gemini-code-assist]

Code Review

This pull request introduces support for Django 6.0, including dependency updates, tuple-casting for lookup parameters, an asynchronous autocommit setter, and a Spanner-specific JSON path compiler. The review feedback highlights critical improvements: resolving syntax, type, and SQL injection issues in compile_json_path by utilizing json.dumps; wrapping the async autocommit operation in self.execute_wrapper to align with Django standards; and fixing invalid shell syntax and compatibility issues in the new test suite script.

[gemini-code-assist]

The current implementation of compile_json_path has several critical issues:

1. Missing $ Prefix: Spanner's JSON path syntax requires the path to start with a $ character (e.g., $.path or $["path"]). Without it, Spanner will raise an Invalid JSON path error at runtime.
2. SQL Injection / Syntax Errors: Single quotes in key_transforms are not escaped, which can lead to SQL syntax errors or potential SQL injection vulnerabilities.
3. TypeError on Integer Keys: If key_transforms contains integer indices (for array lookups), "']['".join(key_transforms) will raise a TypeError because join expects strings.

Using json.dumps (similar to Django's default implementation) solves all of these issues robustly by correctly prepending $, escaping special characters, and handling both string keys and integer indices.

Suggested change

	def compile_json_path(self, key_transforms, fallback_to_null=False):
	# Spanner specific JSON path formatting
	path = "['%s']" % "']['".join(key_transforms)
	return path
	def compile_json_path(self, key_transforms, fallback_to_null=False):
	import json
	return "$" + "".join(f"[{json.dumps(key)}]" for key in key_transforms)

[gemini-code-assist]

In Django, database operations executed asynchronously should be wrapped in self.execute_wrapper to ensure that any custom connection wrappers, instrumentation, or middleware hooks are correctly executed. Wrapping the call in async with self.execute_wrapper: aligns with Django's standard implementation of _a_set_autocommit.

Suggested change

	async def _a_set_autocommit(self, autocommit):
	return await sync_to_async(self._set_autocommit)(autocommit)
	async def _a_set_autocommit(self, autocommit):
	async with self.execute_wrapper:
	return await sync_to_async(self._set_autocommit)(autocommit)

[gemini-code-assist]

There are two issues with the shell configuration here:

1. set -x pipefail is invalid shell syntax. To enable the pipefail option, you must use set -o pipefail.
2. The pipefail option is a bash/zsh extension and is not supported by POSIX-compliant /bin/sh (such as dash on Debian/Ubuntu). To guarantee support, the shebang should be changed to #!/bin/bash.
3. It is highly recommended to enable set -e (errexit) so that the script exits immediately if any setup command (like pip3 install or git clone) fails, preventing silent failures in CI.

Suggested change

	#!/bin/sh
	# Copyright (c) 2020 Google LLC. All rights reserved.
	# Use of this source code is governed by a BSD-style
	# license that can be found in the LICENSE file.
	set -x pipefail
	#!/bin/bash
	# Copyright (c) 2020 Google LLC. All rights reserved.
	# Use of this source code is governed by a BSD-style
	# license that can be found in the LICENSE file.
	set -xe
	set -o pipefail