Fix Context.with(null) edge-case

[mcculls]

What Does This Do

Fix bug where calling context.with((ImplicitContextKeyed) null) drops all other elements.

Motivation

Found while discussing this part of the codebase with Claude

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Jira ticket: [PROJ-IDENT]

[bric3]

Found while discussing this part of the codebase with Claude

Nice

[dd-octo-sts]

🟢 Java Benchmark SLOs — All performance SLOs passed

Suite	Status
Startup	🟢 pass

SLO thresholds are defined here based on automatically generated metrics. A warning is raised when results are within 5% of the threshold.

PR vs. master results

Scenario	Candidate	master	Δ (95% CI of mean)
startup:insecure-bank:iast:Agent	13.98 s	13.90 s	[-0.2%; +1.4%] (no difference)
startup:insecure-bank:tracing:Agent	12.89 s	12.91 s	[-0.9%; +0.6%] (no difference)
startup:petclinic:appsec:Agent	16.90 s	16.01 s	[+1.1%; +10.1%] (significantly worse)
startup:petclinic:iast:Agent	17.02 s	16.95 s	[-0.4%; +1.3%] (no difference)
startup:petclinic:profiling:Agent	16.90 s	16.98 s	[-1.4%; +0.5%] (no difference)
startup:petclinic:sca:Agent	16.79 s	16.89 s	[-1.6%; +0.3%] (no difference)
startup:petclinic:tracing:Agent	15.91 s	16.04 s	[-1.8%; +0.2%] (no difference)

Commit: 2a7aa0c3 · CI Pipeline · Benchmarking Platform UI

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Load and DaCapo benchmarks can be triggered manually in the GitLab pipeline. Results will appear in the Benchmarking Platform UI after completion.

[PerfectSlayer]

Make sense. Thanks for the fix.
Hopefully it won’t impact products / features that depended on the wrong behavior.

Note that some other with API throws exceptions with null keys (so another option would be to through exception too with null ImplicitContextKeyed objects) but I feel silently ignoring the value is still the right thing to do as this method is supposed to bring convenience...

[dd-octo-sts]

/merge

[gh-worker-devflow-routing-ef8351]

View all feedbacks in Devflow UI.

2026-06-18 16:33:42 UTC ℹ️ Start processing command /merge

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2026-06-18 16:33:46 UTC ℹ️ MergeQueue: pull request added to the queue

The expected merge time in master is approximately 1h (p90).

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2026-06-18 17:42:59 UTC ℹ️ MergeQueue: This merge request was merged