scylla/3.11.x: fix ShardAwarenessTest.correctShardInTracingTest for Scylla 2025.1

[nikagra]

Problem

ShardAwarenessTest.correctShardInTracingTest fails on Scylla 2025.1 (both scylla/3.11.4.0 and scylla/3.11.5.15 matrix entries) with:

Expecting: <"shard 0/sl:default"> to start with: <"shard 1">

Two Scylla 2025.1 changes contribute to this failure:

1. Tablets enabled by default for NTS keyspaces (primary, confirmed): Scylla 2025.1 enables tablets by default for NetworkTopologyStrategy keyspaces. With tablets, shard assignment is arbitrary — the driver's hash-based getShardId(token) prediction no longer matches the shard that actually handles the request. The test creates shardawaretest without explicitly disabling tablets, so the expected and actual shards diverge.

2. Service-level suffix in thread names: Since Scylla 2025.1, thread names include a /sl: suffix (e.g. "shard 0/sl:default"). Note: startsWith("shard N") still matches correctly-sharded events — stripping the suffix is defensive hygiene rather than a direct fix.

Pre-existing bug (unmasked): assertThat(anyLocal) is an AssertJ no-op — it wraps the value but never calls .isTrue(). The liveness guard never actually fired even before 2025.1.

Fix

• Add AND TABLETS = {'enabled': false} to CREATE KEYSPACE shardawaretest to restore deterministic hash-based shard assignment.
• Narrow the per-event assertion to only the "querying locally" event (the event that executes on the data-owning shard), making the assertion robust to any future addition of coordinator-side events.
• Strip the /sl:... suffix with replaceFirst("/sl:[^/]*$", "") before startsWith(shard) (defensive hygiene).
• Promote the liveness guard from assertThat(anyLocal) (no-op) to assertTrue(anyLocal, ...) so the guard actually fires when no local event is found.

Testing

Verified via staging job java-driver-matrix-2025.1 build #2 — GREEN on Scylla 2025.1.15-0.20260624.b48b97fb10bd, all 4 driver versions (3.11.4.0, 3.11.5.15, 4.18.1.0, 4.19.0.9).

scylla/4.18.1.0 and scylla/4.19.0.9 pass the test today without changes; this PR targets only 3.11.x (via matrix patches in the companion scylla-java-driver-matrix PR #155).

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ℹ️ Review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: CHILL

Plan: Pro Plus

Run ID: afe7e3fa-3667-42aa-8ae5-02fea92bc155

📥 Commits

Reviewing files that changed from the base of the PR and between 1998141 and 9ea57f2.

📒 Files selected for processing (1)

• driver-core/src/test/java/com/datastax/driver/core/ShardAwarenessTest.java

📝 Walkthrough

Walkthrough

The tracing shard-awareness test now normalizes trace thread names by removing the Scylla 2025.1+ service-level suffix before checking shard prefixes, while still requiring at least one local query event. The keyspace setup in the tracing test now disables tablets and is formatted across multiple lines.

🚥 Pre-merge checks | ✅ 4 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 0.00% which is insufficient. The required threshold is 80.00%.	Write docstrings for the functions missing them to satisfy the coverage threshold.

✅ Passed checks (4 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title clearly matches the main change: fixing ShardAwarenessTest.correctShardInTracingTest for Scylla 2025.1 on 3.11.x.
Description check	✅ Passed	The description is directly related to the test fix and explains the tablets, shard, and tracing-name changes in the patch.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

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Actionable comments posted: 1

🤖 Prompt for all review comments with AI agents

Verify each finding against current code. Fix only still-valid issues, skip the
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Inline comments:
In `@driver-core/src/test/java/com/datastax/driver/core/ShardAwarenessTest.java`:
- Line 95: The test assertion in ShardAwarenessTest currently uses the
no-message assertTrue overload, so update the anyLocal check to include a clear
failure message. Locate the assertion in the shard awareness test and change it
to document that no "querying locally" event was observed, so failures are
easier to diagnose.

🪄 Autofix (Beta)

Fix all unresolved CodeRabbit comments on this PR:

• Push a commit to this branch (recommended)
• Create a new PR with the fixes

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ℹ️ Review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: CHILL

Plan: Pro Plus

Run ID: d34dc26c-9c6e-4949-8d75-e1d0e8854e1a

📥 Commits

Reviewing files that changed from the base of the PR and between 5f4f988 and 318e0a4.

📒 Files selected for processing (1)

• driver-core/src/test/java/com/datastax/driver/core/ShardAwarenessTest.java