i think that this works now

tests/test_pool.py

@@ -0,0 +1,126 @@
+import pytest
+
+from pool import (
+    append_token,
+    pop_token,
+    pool_size,
+    get_first_token,
+    trigger_refill,
+    wait_for_token,
+)
+import pool as p
+
+
+@pytest.fixture
+def fresh_pool(tmp_path, monkeypatch):
+    tokens_file = tmp_path / "tokens.txt"
+    tokens_file.write_text("")
+    monkeypatch.setattr(p, "TOKENS_FILE", tokens_file)
+    monkeypatch.setattr(p, "DATA_DIR", tmp_path)
+    return tokens_file
+
+
+@pytest.mark.asyncio
+async def test_empty_pool(fresh_pool):
+    assert await get_first_token() is None
+    assert await pop_token() is None
+    assert await pool_size() == 0
+
+
+@pytest.mark.asyncio
+async def test_append_token(fresh_pool):
+    await append_token("token1")
+    assert await pool_size() == 1
+    assert await get_first_token() == "token1"
+
+
+@pytest.mark.asyncio
+async def test_append_multiple_tokens(fresh_pool):
+    await append_token("token1")
+    await append_token("token2")
+    await append_token("token3")
+
+    assert await pool_size() == 3
+    assert await get_first_token() == "token1"
+
+
+@pytest.mark.asyncio
+async def test_pop_token(fresh_pool):
+    await append_token("token1")
+    await append_token("token2")
+
+    t = await pop_token()
+    assert t == "token1"
+    assert await pool_size() == 1
+    assert await get_first_token() == "token2"
+
+
+@pytest.mark.asyncio
+async def test_pop_until_empty(fresh_pool):
+    await append_token("only_one")
+
+    t = await pop_token()
+    assert t == "only_one"
+
+    assert await pop_token() is None
+    assert await pool_size() == 0
+
+
+@pytest.mark.asyncio
+async def test_get_first_token_peek(fresh_pool):
+    await append_token("token1")
+
+    t = await get_first_token()
+    assert t == "token1"
+
+    t2 = await get_first_token()
+    assert t2 == "token1"
+
+    assert await pool_size() == 1
+
+
+@pytest.mark.asyncio
+async def test_token_with_whitespace(fresh_pool):
+    await append_token("  token_with_spaces  ")
+    t = await get_first_token()
+    assert t == "token_with_spaces"
+
+
+@pytest.mark.asyncio
+async def test_persist_to_file(fresh_pool):
+    await append_token("token1")
+    await append_token("token2")
+
+    content = fresh_pool.read_text()
+    assert "token1" in content
+    assert "token2" in content
+
+
+@pytest.mark.asyncio
+async def test_wait_for_token_with_existing(fresh_pool):
+    await append_token("existing_token")
+
+    token = await wait_for_token()
+    assert token == "existing_token"
+
+
+@pytest.mark.asyncio
+async def test_wait_for_token_empty_no_accounts(fresh_pool, tmp_path, monkeypatch):
+    import emails
+
+    emails_file = tmp_path / "emails.txt"
+    emails_file.write_text("")
+    monkeypatch.setattr(emails, "EMAILS_FILE", emails_file)
+
+    token = await wait_for_token()
+    assert token is None
+
+
+@pytest.mark.asyncio
+async def test_trigger_refill_does_not_block(fresh_pool):
+    import asyncio
+
+    await trigger_refill()
+    await asyncio.sleep(0.01)
+
+    assert True