Add contract test: set_delegate() called twice overwrites the previous delegate

[Austinaminu2]

Description

No existing test in `contracts/streaming/src/test.rs` verifies that calling `set_delegate()` a second time replaces the previously-registered delegate (i.e. the old delegate can no longer withdraw after being overwritten).

Task

Add a test that sets a delegate, sets a different delegate, and asserts `get_delegate()` returns the second address (and that the first delegate's authorization is no longer valid).

Good for contributors because

Small, focused addition to the existing delegate test suite in `test.rs`.

[Komelove]

@Komelove has applied to work on this issue as part of the Stellar Wave Program's 8th wave.

I’d be happy to take this issue. I’ve looked through the requirements and have a plan for approaching the implementation. I’ll investigate the existing code and dependencies, make the required changes, verify the behaviour with tests, and provide a concise PR explaining what was changed. I can start immediately and will communicate any blockers during development.

ℹ️ Repo Maintainers: To accept this application, review their application or assign @Komelove to this issue.

[kolawoleoluwaferanmi014-a11y]

@kolawoleoluwaferanmi014-a11y has applied to work on this issue as part of the Stellar Wave Program's 8th wave.

Hi, I’ve gone through the issue in detail and understand what needs to be addressed. I’m confident I can implement the required changes cleanly and efficiently. I’d be glad to take ownership of this issue.

ℹ️ Repo Maintainers: To accept this application, review their application or assign @kolawoleoluwaferanmi014-a11y to this issue.

[Teejay2696]

@Teejay2696 has applied to work on this issue as part of the Stellar Wave Program's 8th wave.

I can start work on this now

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[Abba073]

@Abba073 has applied to work on this issue as part of the Stellar Wave Program's 8th wave.

Hi maintainer,I’m interested in contributing to the task

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[nwosum113-ui]

@nwosum113-ui has applied to work on this issue as part of the Stellar Wave Program's 8th wave.

bro give me issue

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[zeey-247]

@zeey-247 has applied to work on this issue as part of the Stellar Wave Program's 8th wave.

Hello, I understand the expected outcome and am ready to implement the required changes. I'd appreciate being assigned this issue.

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[somotochukwu-dev]

@somotochukwu-dev has applied to work on this issue as part of the Stellar Wave Program's 8th wave.

Hi
Please assign this issue to me
Thanks

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[Macnelson9]

@Macnelson9 has applied to work on this issue as part of the Stellar Wave Program's 8th wave.

Hi team, I'd love to work on this issue.

I'm a Full-Stack Web3 Developer with experience building Rust-based smart contracts and modern frontend applications using React/Next.js and TypeScript. I'm comfortable working across the entire stack, from contract development and integration to creating responsive, user-friendly interfaces.

I can deliver a clean, well-tested implementation that follows the project's standards and will provide regular progress updates throughout development.

Looking forward to contributing.

ℹ️ Repo Maintainers: To accept this application, review their application or assign @Macnelson9 to this issue.

[topsonDev]

@topsonDev has applied to work on this issue as part of the Stellar Wave Program's 8th wave.

hello maintainer, i would like to work on this task and resolve it.

ℹ️ Repo Maintainers: To accept this application, review their application or assign @topsonDev to this issue.

[drips-wave]

Congratulations, @Macnelson9! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on August 31, 2026.

🧑‍💻 @Macnelson9: Please resolve the issue such that the repo's maintainers have enough time to review your contribution before the due date. You'll earn Points for completing the issue on-time, which will make you eligible for a share of the Stellar Wave Program's reward pool.

Warning

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