test(invoice-token): comprehensive test matrix validating Error::NotInit across all public entry points

[chizzy192]

Context & Problem Statement

The InvoiceToken contract in contracts/invoice-token/src/lib.rs exposes over 30 public entry points (SEP-41 token operations, allowances, administrative setters, batch minting, and pause controls). When invoked on an uninitialized contract instance, every functional method must reject with Error::NotInit without panicking or modifying state.

This issue adds a single comprehensive test suite test_uninitialized_methods_rejected in contracts/invoice-token/src/test.rs that systematically exercises every public entry point on a freshly deployed, uninitialized contract instance.

Architectural Motivation & Technical Requirements

• In contracts/invoice-token/src/test.rs:
  • Instantiate a clean InvoiceTokenClient without invoking initialize().
  • Assert that calling each of the following returns Error::NotInit:
    • Read methods: name, symbol, decimals, total_supply, balance, balance_batch, allowance, get_nonce, invoice_id, transfer_locked, paused.
    • Write methods: transfer, transfer_from, approve, extend_allowance, revoke_approval, burn, burn_from, mint, mint_batch, set_transfer_locked, set_minter, set_decimals, set_paused.
• Verify that no storage keys are written during failed invocations.

Acceptance Criteria

• All 30+ public methods tested on uninitialized instance.
• Every invocation asserts Error::NotInit (or exact contract error code).
• cargo test -p invoice-token passes cleanly.

Target Branch: dev
Estimated Effort: 1–4 hours | Delivery: 1–2 days
Difficulty: Easy

[Sajjadd-dev]

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

Hello, I’d like to contribute to this issue and would appreciate the opportunity to work on it. Thank you.

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[neyij]

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

hi, i would like to work on this.

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

[drips-wave]

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

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