Adding support for CAS/CAD commands.

[petyaslavova]

Adding support for new CAS/CAD commands that are part of Redis 8.4 release.

1. Adding new command: DIGEST
   Command definition: DIGEST key
   Get the hash digest of the value stored in key, as a hex string.

2. Extending SET command to enable the following arguments:
   Command definition: SET key value [NX | XX | IFEQ match-value | IFNE match-value | IFDEQ match-digest | IFDNE match-digest] [GET] [EX seconds | PX milliseconds | EXAT unix-time-seconds | PXAT unix-time-milliseconds | KEEPTTL]
   IFEQ match-value - Set the key’s value and expiration only if its current value is equal to match-value. If key doesn’t exist - it won’t be created.
   IFNE match-value - Set the key’s value and expiration only if its current value is not equal to match-value. If key doesn’t exist - it will be created.
   IFDEQ match-digest - Set the key’s value and expiration only if the digest of its current value is equal to match-digest. If key doesn’t exist - it won’t be created.
   IFDNE match-digest - Set the key’s value and expiration only if the digest of its current value is not equal to match-digest. If key doesn’t exist - it will be created.

3. Adding new command DELEX
   Command definition: DELEX key [IFEQ match-value | IFNE match-value | IFDEQ match-digest | IFDNE match-digest]
   Conditionally removes the specified key. A key is ignored if it does not exist.

   IFEQ match-value - Delete the key only if its value is equal to match-value
   IFNE match-value - Delete the key only if its value is not equal to match-value
   IFDEQ match-digest - Delete the key only if the digest of its value is equal to match-digest
   IFDNE match-digest - Delete the key only if the digest of its value is not equal to match-digest

[Copilot]

Pull Request Overview

This pull request adds support for two new Redis 8.4 commands (DELEX and DIGEST) and extends the SET command with new conditional options (IFEQ, IFNE, IFDEQ, IFDNE). The implementation includes both synchronous and asynchronous variants along with comprehensive test coverage.

Key Changes:

• Added delex() method for conditional key deletion based on value or digest matching
• Added digest() method to compute XXH3 hash digests of string values
• Extended set() method with four new conditional parameters for atomic compare-and-set operations
• Introduced at_most_one_value_set() helper function to simplify mutual exclusivity validation
• Added DIGEST command to cluster read-only commands list

Reviewed Changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated 8 comments.

Show a summary per file

File	Description
redis/commands/helpers.py	Adds at_most_one_value_set() helper function for mutual exclusivity checks
redis/commands/core.py	Implements delex() and digest() methods, extends set() with new conditionals, refactors mutual exclusivity checks
redis/commands/cluster.py	Adds DIGEST to read-only commands list for cluster support
tests/test_commands.py	Comprehensive tests for delex(), digest(), and extended set() functionality
tests/test_asyncio/test_commands.py	Async variants of all new tests

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.