fix(dotnet): declare FFE capability from 3.53

[pavlokhrebto]

Motivation

dd-trace-dotnet 3.53.0 recognizes DD_FEATURE_FLAGS_CONFIGURATION_SOURCE=remote_config and reports FFE_FLAG_CONFIGURATION_RULES during the Remote Config capability completeness test. The capability registry does not declare that bit for dotnet, so released-version validation rejects the correctly reported capability as seen_but_not_expected and fails the dotnet parametric job.

Changes

Updates the version-aware dotnet capability registry so FFE_FLAG_CONFIGURATION_RULES is expected starting with dotnet 3.53.0. Earlier dotnet versions keep their existing expected capability set.

Decisions

The capability is declared at >=3.53.0 instead of in the dotnet base set. Earlier versions contain the registration code, but Feature Flags only started when the legacy DD_EXPERIMENTAL_FLAGGING_PROVIDER_ENABLED opt-in was set, which DEFAULT_ENVVARS does not set, so the capability was never observable. 3.53.0 enables Feature Flags by default, so the explicit remote_config source in DEFAULT_ENVVARS is honored, the tracer subscribes to FFE_FLAGS, and the capability becomes observable. dotnet advertises it only for the remote_config source, matching Node, which gates on DD_FEATURE_FLAGS_CONFIGURATION_SOURCE === 'remote_config' in proxy.js.

Verification

• ./format.sh — no changes
• ./run.sh TEST_THE_TEST tests/test_the_test/test_capabilities.py — passed
• dd-trace-dotnet PR #9044, where test_default_capability_completeness currently fails with seen_but_not_expected_capabilities={<Capabilities.FFE_FLAG_CONFIGURATION_RULES: 46>}

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[github-actions]

CODEOWNERS have been resolved as:

tests/parametric/capabilities.yml                                       @DataDog/system-tests-core @DataDog/apm-sdk-capabilities

[datadog-prod-us1-5]

 

⚠️ Warnings

❌ Your PR has failed checks. Please review the issues below and take necessary action before merging.

🚦 2 Pipeline jobs failed

Testing the test | System Tests (dotnet, dev) / parametric / parametric (1) — 🔧 Needs a code fix, caused by this PR

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1 failed test. Assertion Error: expected_but_not_seen_capabilities={<Capabilities.FFE_FLAG_CONFIGURATION_RULES: 46>}; Update capabilities.yml to fix this.

Testing the test | all-jobs-are-green

View more details · View in GitHub Actions

Job did not run: blocked by a failed job in an earlier pipeline stage.

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Branch: pavlo.khrebto/dotnet-3.53-ffe-capability

Testing the test | System Tests (dotnet, dev) / parametric / parametric (1)
Commit: 476528611a4f9674fb8d032976e9d6e017dff56c
Error (code / test):
1 failed test. Assertion Error: expected_but_not_seen_capabilities={<Capabilities.FFE_FLAG_CONFIGURATION_RULES: 46>}; Update capabilities.yml to fix this.
CI job: https://github.com/DataDog/system-tests/actions/runs/33165186602/job/98829352629

ℹ️ Info

No other issues found (see more)

🧪 All tests passed
❄️ No new flaky tests detected

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