feat: add transfer tests

banteg · Dec 11, 2020 · 4feb6f7 · 4feb6f7
1 parent 6127e9c
commit 4feb6f7
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diff --git a/tests/conftest.py b/tests/conftest.py
@@ -19,3 +19,13 @@ def col(interface, whale):
 @pytest.fixture
 def duck(Duck, whale):
     return Duck.deploy({"from": whale})
+
+
+@pytest.fixture
+def fat_duck(duck, whale, col, accounts):
+    # a duck with two accounts stuffed with balances
+    col.approve(duck, 2 ** 256 - 1)
+    duck.migrate()
+    duck.transfer(accounts[0], duck.balanceOf(whale) / 2)
+    duck.transfer(accounts[1], duck.balanceOf(whale) / 2)
+    return duck
diff --git a/tests/test_transfers.py b/tests/test_transfers.py
@@ -0,0 +1,43 @@
+import brownie
+
+
+def test_transfer(accounts, fat_duck):
+    a, b = accounts[0:2]
+    a_balance = fat_duck.balanceOf(a)
+    b_balance = fat_duck.balanceOf(b)
+    # cannot send to zero address or token contract
+    with brownie.reverts():
+        fat_duck.transfer(fat_duck, fat_duck.balanceOf(a), {"from": a})
+    with brownie.reverts():
+        fat_duck.transfer("0x" + "0" * 40, fat_duck.balanceOf(a), {"from": a})
+    # normal transfers work
+    fat_duck.transfer(b, fat_duck.balanceOf(a), {"from": a})
+    assert fat_duck.balanceOf(a) == 0
+    assert fat_duck.balanceOf(b) == a_balance + b_balance
+
+
+def test_transferFrom(accounts, fat_duck):
+    a, b, c = accounts[0:3]
+    a_balance = fat_duck.balanceOf(a)
+    b_balance = fat_duck.balanceOf(b)
+    # cannot send without approval
+    with brownie.reverts():
+        fat_duck.transferFrom(a, c, a_balance, {"from": c})
+    # send with approval
+    fat_duck.approve(c, fat_duck.balanceOf(a) // 2, {"from": a})
+    assert fat_duck.allowance(a, c) == fat_duck.balanceOf(a) // 2
+    # cannot send more than approved
+    with brownie.reverts():
+        fat_duck.transferFrom(a, b, fat_duck.balanceOf(a), {"from": c})
+    # transfer with approval
+    assert fat_duck.balanceOf(a) == a_balance
+    assert fat_duck.balanceOf(b) == b_balance
+    normal = fat_duck.transferFrom(a, b, fat_duck.balanceOf(a) // 2, {"from": c})
+    assert fat_duck.balanceOf(a) == a_balance // 2
+    assert fat_duck.balanceOf(b) == b_balance + a_balance // 2
+    # unlimited approval saves gas
+    fat_duck.approve(c, 2 ** 256 - 1, {"from": a})
+    unlimited = fat_duck.transferFrom(a, b, fat_duck.balanceOf(a), {"from": c})
+    assert unlimited.gas_used < normal.gas_used
+    assert fat_duck.balanceOf(a) == 0
+    assert fat_duck.balanceOf(b) == a_balance + b_balance