test: verify get_total_key_supply is scoped per creator

[stableprogrammer]

Closes #701

Problem

Issue #701 requires unit tests confirming that get_total_key_supply tracks supply per creator address, not as a global counter. Without explicit isolation tests, a regression that accidentally shares a single supply counter across all creators — or that lets one creator's buy/sell mutate another's supply — would go undetected.

The contract exposes two supply views:

• get_total_key_supply(creator) → u32 — unchecked, returns 0 for unregistered creators
• get_creator_supply(creator) → Result<u32, ContractError> — checked, returns Err(NotRegistered) for unregistered creators

Both are tested.

What changed

New file: creator-keys/tests/total_supply_per_creator.rs

17 unit tests, each targeting one narrow invariant so failures pinpoint exactly what broke:

Test	What it proves
test_supply_is_zero_immediately_after_creator_registration	Baseline — fresh creator starts at 0 before any buys
test_supply_equals_ten_after_ten_buys_for_creator_a	Issue spec step 1 — buy 10, assert supply = 10
test_supply_equals_five_after_five_buys_for_creator_b	Issue spec step 2 — buy 5, assert supply = 5
test_creator_a_supply_unaffected_by_creator_b_buys	Issue spec step 3 — A stays at 10 after B buys 5
test_creator_b_supply_unaffected_by_creator_a_buys	Symmetrical check — B stays at 5 after A buys 10
test_sell_three_keys_decrements_creator_a_supply_from_ten_to_seven	Issue spec step 4 — sell 3 from A, assert supply = 7
test_selling_from_creator_a_does_not_affect_creator_b_supply	Issue spec: sells on A must not bleed into B
test_selling_from_creator_b_does_not_affect_creator_a_supply	Symmetrical — sells on B must not bleed into A
test_supply_increments_by_one_per_buy	Supply counter increments exactly 1 per buy, checked after every individual purchase
test_supply_decrements_by_one_per_sell	Supply counter decrements exactly 1 per sell, checked after every individual sell
test_supply_accumulates_across_multiple_buyers_for_same_creator	3 + 4 + 2 buys across three wallets → supply = 9 (sum, not per-wallet cap)
test_three_creators_maintain_independent_supply_counters	Three registrations with 4 / 7 / 2 buys each — all three supplies remain exact
test_supply_reaches_zero_after_selling_all_keys	Selling all 3 keys drops supply back to 0
test_unregistered_creator_returns_not_registered_from_checked_view	Issue spec step 5 — try_get_creator_supply on unknown address returns Err(Ok(NotRegistered))
test_unregistered_creator_returns_zero_from_unchecked_view	get_total_key_supply on unknown address returns 0 (safe-read design)
test_get_total_key_supply_is_idempotent_and_read_only	Calling the view three times in a row returns the same value — no hidden state mutation
test_total_supply_equals_sum_of_all_holder_balances	Supply invariant: total supply = Σ holder balances, verified after mixed buys and sells

Test approach

• All tests use the contract_test_env shared helpers (register_creator_keys, register_test_creator, set_pricing_and_fees, test_env_with_auths) so they work under both flat and bonding-curve pricing.
• A local buy_n_keys helper fetches a live get_buy_quote before every individual purchase — this keeps tests correct under any future pricing change.
• Each test asserts one invariant with a descriptive failure message that names the expected and actual values and explains why the check matters.

Acceptance criteria

• Supply scoped correctly per creator
• Creator A supply unaffected by creator B buys
• Sell correctly decrements supply
• Unregistered creator returns NotRegistered from the checked view

Test run

running 17 tests
test test_supply_is_zero_immediately_after_creator_registration ... ok
test test_supply_equals_ten_after_ten_buys_for_creator_a ... ok
test test_supply_equals_five_after_five_buys_for_creator_b ... ok
test test_creator_a_supply_unaffected_by_creator_b_buys ... ok
test test_creator_b_supply_unaffected_by_creator_a_buys ... ok
test test_sell_three_keys_decrements_creator_a_supply_from_ten_to_seven ... ok
test test_selling_from_creator_a_does_not_affect_creator_b_supply ... ok
test test_selling_from_creator_b_does_not_affect_creator_a_supply ... ok
test test_supply_increments_by_one_per_buy ... ok
test test_supply_decrements_by_one_per_sell ... ok
test test_supply_accumulates_across_multiple_buyers_for_same_creator ... ok
test test_three_creators_maintain_independent_supply_counters ... ok
test test_supply_reaches_zero_after_selling_all_keys ... ok
test test_unregistered_creator_returns_not_registered_from_checked_view ... ok
test test_unregistered_creator_returns_zero_from_unchecked_view ... ok
test test_get_total_key_supply_is_idempotent_and_read_only ... ok
test test_total_supply_equals_sum_of_all_holder_balances ... ok

test result: ok. 17 passed; 0 failed; 0 ignored; 0 measured; 0 filtered out; finished in 1.39s

[Chucks1093]

Nice work Stable programmer !!!