headroom/tests/test_providers/test_universal.py
Tejas Chopra 06add9e9d8
fix(providers): stop pricing modern content blocks at zero (#2760)
## Description

Each token counter in `headroom/providers/` had grown its own shortened
content-block walker, handling only the shapes its provider was expected
to send. Everything else fell through and contributed **nothing**.

Measured on one 6,800-char block, via `count_messages` of a single-block
message — so 7–8 is message overhead alone:

| block type | OpenAI ctr | Anthropic ctr |
|---|---|---|
| `text` (control) | 3409 | 3748 |
| `tool_result` | **8** | 3748 |
| `thinking` | **8** | **7** |
| `document` | **8** | **7** |
| `mcp_tool_result` | **8** | **7** |
| `output_text` | **8** | **7** |
| `refusal` | **8** | **7** |

Two things make this worse than a coverage gap:

1. **Each counter zeroed blocks from its own provider.** `output_text`
and `refusal` are OpenAI Responses shapes; `thinking` and `document` are
Anthropic's.
2. **These are the counters the live pipelines use.** `proxy/server.py`
builds them with `AnthropicProvider` / `OpenAIProvider`, so this is the
main request path — not an edge case. #2743 fixed this for
`/v1/compress` only, by routing that route to the registry tokenizers,
whose `BaseTokenizer` walker is complete.

Closes #

## Type of Change

- [x] Bug fix (non-breaking change that fixes an issue)

## Changes Made

Rather than add a **fifth** partial walker, the counters now delegate to
the audited one:

- `tokenizers/base.py` — new `count_content_blocks(parts,
count_text_fn)` plus a thin `_DelegatingBlockCounter` adapter, since the
provider counters are not `BaseTokenizer` subclasses. `BaseTokenizer`
itself is untouched.
- `providers/openai.py`, `providers/anthropic.py`,
`providers/openai_compatible.py` — list-content branches delegate.

**Why delegate instead of adding a `count_text(str(block))` catch-all:**
that would serialize a base64 blob and price it as text.
`tiktoken_counter.py` already documents the failure — a 1MB image
becomes ~330K phantom tokens. The shared walker gives media a
pixel/byte-based estimate.

**Scope:** the three counters that accumulate token counts. `google.py`
and `cohere.py` extract a *text string* first and count that, so the
same defect there needs a differently-shaped fix — left as a follow-up.

## Testing

- [x] Unit tests pass
- [x] Linting passes (`ruff check` + `format --check`, pinned 0.15.17)
- [x] New tests added
- [x] Manual testing performed

### Test Output

```text
$ pytest tests/test_provider_counter_content_blocks.py -q
12 passed in 0.52s

$ uvx ruff@0.15.17 check headroom/ tests/... --exclude headroom/dashboard/templates
All checks passed!
```

**After the fix**, every shape lands within ~1% of the equivalent plain
text, and media stays bounded:

```text
block                  OpenAI  Anthropic
text (control)           3409       3748
tool_result              3409       3748
thinking                 3419       3759
document                 3423       3763
mcp_tool_result          3422       3762
output_text              3420       3760
refusal                  3421       3761
image b64 200KB          1608       1607   <- pixel estimate, not ~50K as text
```

## Real Behavior Proof — including a regression I caught

**This change flipped an existing test**, and I only found it because
every suite was run against clean `upstream/main` in the same
environment with the failure sets diffed:

```text
before the test rewrite:
  upstream/main : 1 failed, 104 passed
  this branch   : 2 failed, 103 passed        <- regression
  diff          : + test_openai_compatible_token_counter_ignores_unhandled_content_shapes
```

That test asserted `content: [{"type": "image"}, 123] == 8` — i.e. it
**pinned the defect**, that unhandled shapes contribute nothing.
Rewritten as `..._prices_declared_media`: a declared image is now priced
(1608) while a bare int is still correctly ignored (8), with the
rationale in the docstring.

```text
after the rewrite:
  upstream/main : 1 failed, 104 passed, 10 skipped, 25 errors
  this branch   : 1 failed, 104 passed, 10 skipped, 25 errors
  failure sets  : IDENTICAL
```

- **Pre-existing, not from this change:** the 1 failure and all 25
errors. The errors are all in
`test_compress_route_tokenizer_by_model.py`, whose loopback `TestClient`
fixture this throwaway env cannot satisfy.
- **Environment note:** `content_router` and several suites need the
compiled `headroom._core`, which isn't in a fresh worktree (gitignored,
built in-place). I copied the built `.so` in to run these and removed it
before committing.
- **Not tested:** no live provider call, so the *absolute* accuracy of
the 1600 image estimate against a real Anthropic/OpenAI bill is
unverified — it is the value `BaseTokenizer` already used, and this PR
only changes which blocks reach it.

## Review Readiness

- [x] I have performed a self-review
- [x] This PR is ready for human review

## Checklist

- [x] My code follows the project's style guidelines
- [x] I have performed a self-review of my code
- [x] I have commented my code, particularly in hard-to-understand areas
- [x] My changes generate no new warnings
- [x] I have added tests that prove my fix is effective
- [x] I did **not** edit `CHANGELOG.md`

## Related

Fourth PR from one tokenizer-consistency audit: #2757 (litellm total
prompt / `--budget`), #2758 (HuggingFace chat templates, `gpt-5`,
gateway-wrapped names), #2759 (router token units). Plus #2756, which
splits the local/provider token scales in `RequestOutcome`.

🤖 Generated with [Claude Code](https://claude.com/claude-code)
2026-08-03 22:40:38 -07:00

525 lines
20 KiB
Python

"""Tests for universal provider support.
Tests OpenAICompatibleProvider, GoogleProvider, and LiteLLMProvider.
"""
from __future__ import annotations
import pytest
from headroom.providers import (
GoogleProvider,
LiteLLMProvider,
ModelCapabilities,
OpenAICompatibleProvider,
create_anyscale_provider,
create_fireworks_provider,
create_groq_provider,
create_litellm_provider,
create_lmstudio_provider,
create_ollama_provider,
create_together_provider,
create_vllm_provider,
is_litellm_available,
)
def _transformers_available() -> bool:
"""Check if transformers is available."""
try:
import transformers # noqa: F401
return True
except ImportError:
return False
class TestOpenAICompatibleProvider:
"""Tests for OpenAICompatibleProvider."""
def test_init_default(self):
"""Test initialization with defaults."""
provider = OpenAICompatibleProvider()
assert provider.name == "openai_compatible"
assert provider.base_url is None
def test_init_with_config(self):
"""Test initialization with configuration."""
provider = OpenAICompatibleProvider(
name="custom",
base_url="http://localhost:8080/v1",
api_key="test-key",
)
assert provider.name == "custom"
assert provider.base_url == "http://localhost:8080/v1"
assert provider.api_key == "test-key"
def test_supports_any_model(self):
"""Test that provider supports any model."""
provider = OpenAICompatibleProvider()
assert provider.supports_model("any-model") is True
assert provider.supports_model("llama-3") is True
assert provider.supports_model("custom-finetuned") is True
@pytest.mark.skipif(
not _transformers_available(),
reason="transformers not installed - needed for HuggingFace tokenizer",
)
def test_get_token_counter(self):
"""Test getting token counter."""
provider = OpenAICompatibleProvider()
counter = provider.get_token_counter("llama-3-8b")
assert counter is not None
# Should be able to count tokens
count = counter.count_text("Hello, world!")
assert count > 0
def test_get_context_limit_known_model(self):
"""Test context limit for known models."""
provider = OpenAICompatibleProvider()
# Llama 3.1 has 128K context
limit = provider.get_context_limit("llama-3.1-8b")
assert limit == 128000
def test_get_context_limit_deepseek_v3_is_1m(self):
"""DeepSeek V3/V4 support 1M context, not 128K (#1038)."""
provider = OpenAICompatibleProvider()
assert provider.get_context_limit("deepseek-v3") == 1048576
assert provider.get_context_limit("deepseek-v4") == 1048576
assert provider.get_context_limit("deepseek") == 1048576
assert provider.get_context_limit("deepseek-v2") == 128000
assert provider.get_context_limit("deepseek-v3.2") == 128000
assert provider.get_context_limit("deepseek-v4-pro") == 1_000_000
assert provider.get_context_limit("deepseek-v4-flash") == 1_000_000
assert provider.get_context_limit("deepseek-r1") == 131072
assert provider.get_context_limit("deepseek-coder-v2") == 128000
def test_get_context_limit_unknown_model(self):
"""Test context limit for unknown models (defaults to 128K)."""
provider = OpenAICompatibleProvider()
limit = provider.get_context_limit("unknown-model")
assert limit == 128000
def test_register_model(self):
"""Test registering a custom model."""
provider = OpenAICompatibleProvider()
provider.register_model(
"my-model",
context_window=64000,
max_output_tokens=8192,
input_cost_per_1m=1.0,
output_cost_per_1m=2.0,
)
assert provider.get_context_limit("my-model") == 64000
def test_estimate_cost_registered_model(self):
"""Test cost estimation for registered model."""
provider = OpenAICompatibleProvider()
provider.register_model(
"priced-model",
input_cost_per_1m=1.0,
output_cost_per_1m=2.0,
)
cost = provider.estimate_cost(
input_tokens=1000000,
output_tokens=500000,
model="priced-model",
)
assert cost == 2.0 # 1.0 + 1.0
def test_estimate_cost_unknown_model(self):
"""Test cost estimation returns None for unknown model."""
provider = OpenAICompatibleProvider()
cost = provider.estimate_cost(
input_tokens=1000,
output_tokens=500,
model="unknown-model",
)
assert cost is None
def test_register_model_accepts_capabilities_object(self):
provider = OpenAICompatibleProvider()
caps = ModelCapabilities(model="caps-model", context_window=16000, tokenizer_backend="test")
provider.register_model("caps-model", capabilities=caps)
assert provider.get_context_limit("caps-model") == 16000
def test_get_token_counter_uses_registered_tokenizer_backend(self, monkeypatch):
recorded: list[tuple[str, str | None]] = []
class DummyTokenizer:
def count_text(self, text: str) -> int:
return len(text.split())
monkeypatch.setattr(
"headroom.providers.openai_compatible.get_tokenizer",
lambda model, backend=None: recorded.append((model, backend)) or DummyTokenizer(),
)
provider = OpenAICompatibleProvider(
models={
"custom-model": ModelCapabilities(
model="custom-model",
tokenizer_backend="custom-backend",
)
}
)
counter = provider.get_token_counter("custom-model")
assert counter.count_text("one two three") == 3
assert recorded == [("custom-model", "custom-backend")]
def test_openai_compatible_token_counter_counts_message_parts(self, monkeypatch):
class DummyTokenizer:
def count_text(self, text: str) -> int:
return len(text)
monkeypatch.setattr(
"headroom.providers.openai_compatible.get_tokenizer",
lambda model, backend=None: DummyTokenizer(),
)
counter = OpenAICompatibleProvider().get_token_counter("demo-model")
tokens = counter.count_message(
{
"role": "user",
"content": [{"type": "text", "text": "hi"}, "there"],
"name": "tester",
"tool_calls": [{"function": {"name": "lookup", "arguments": '{"x":1}'}}],
"tool_call_id": "call_123",
}
)
total = counter.count_messages(
[
{"role": "user", "content": "hello"},
{"role": "assistant", "content": ["world"]},
]
)
assert tokens == 55
assert total == 34
def test_openai_compatible_token_counter_prices_declared_media(self, monkeypatch):
"""An image block costs tokens; a non dict/str part still contributes none.
This previously asserted that BOTH contribute 0 — i.e. it pinned the
defect. The counter handled only ``type == "text"``, so every other block
priced at ~0: measured on a 6,800-char block, tool_result / thinking /
document / mcp_tool_result all returned 8 tokens, overhead only. Counters
now delegate to the shared walker, which prices a declared image with the
pixel-based estimate (1600, the max after provider auto-resize) rather
than either ignoring it or serializing its base64 as text.
"""
class DummyTokenizer:
def count_text(self, text: str) -> int:
return len(text)
monkeypatch.setattr(
"headroom.providers.openai_compatible.get_tokenizer",
lambda model, backend=None: DummyTokenizer(),
)
counter = OpenAICompatibleProvider().get_token_counter("demo-model")
# Non-list, non-str content is still ignored.
assert counter.count_message({"role": "user", "content": {}}) == 8
# A bare int is not a block and still contributes nothing.
assert counter.count_message({"role": "user", "content": [123]}) == 8
# A declared image is now priced instead of silently free.
assert counter.count_message({"role": "user", "content": [{"type": "image"}, 123]}) == 1608
def test_get_context_limit_prefix_output_buffer_and_partial_pricing(self):
provider = OpenAICompatibleProvider(
models={
"buffered": ModelCapabilities(
model="buffered",
max_output_tokens=1200,
input_cost_per_1m=1.0,
)
}
)
assert provider.get_context_limit("mistral-custom") == 32768
assert provider.get_output_buffer("buffered", default=4000) == 1200
assert provider.get_output_buffer("unknown", default=2222) == 2222
assert provider.estimate_cost(1000, 1000, "buffered") is None
class TestModelCapabilities:
"""Tests for ModelCapabilities dataclass."""
def test_default_values(self):
"""Test default capability values."""
caps = ModelCapabilities(model="test-model")
assert caps.context_window == 128000
assert caps.max_output_tokens == 4096
assert caps.supports_tools is True
assert caps.supports_vision is False
assert caps.supports_streaming is True
def test_custom_values(self):
"""Test custom capability values."""
caps = ModelCapabilities(
model="custom-model",
context_window=32000,
max_output_tokens=16384,
supports_tools=False,
supports_vision=True,
input_cost_per_1m=0.5,
output_cost_per_1m=1.5,
)
assert caps.context_window == 32000
assert caps.max_output_tokens == 16384
assert caps.supports_tools is False
assert caps.supports_vision is True
assert caps.input_cost_per_1m == 0.5
assert caps.output_cost_per_1m == 1.5
class TestGoogleProvider:
"""Tests for GoogleProvider."""
@pytest.fixture
def provider(self):
"""Create Google provider."""
return GoogleProvider()
def test_name(self, provider):
"""Test provider name."""
assert provider.name == "google"
def test_supports_gemini_models(self, provider):
"""Test support for Gemini models."""
assert provider.supports_model("gemini-2.0-flash") is True
assert provider.supports_model("gemini-1.5-pro") is True
assert provider.supports_model("gemini-1.5-flash") is True
def test_not_supports_other_models(self, provider):
"""Test non-support for other models."""
assert provider.supports_model("gpt-4o") is False
assert provider.supports_model("claude-3") is False
def test_get_token_counter(self, provider):
"""Test getting token counter."""
counter = provider.get_token_counter("gemini-2.0-flash")
assert counter is not None
count = counter.count_text("Hello, world!")
assert count > 0
def test_get_context_limit_gemini_2(self, provider):
"""Test context limit for Gemini 2.0."""
limit = provider.get_context_limit("gemini-2.0-flash")
# LiteLLM returns 1048576 (2^20), fallback returns 1000000
assert limit in (1000000, 1048576) # ~1M tokens
def test_get_context_limit_gemini_1_5_pro(self, provider):
"""Test context limit for Gemini 1.5 Pro (2M!)."""
limit = provider.get_context_limit("gemini-1.5-pro")
# LiteLLM returns 2097152 (2^21), fallback returns 2000000
assert limit in (2000000, 2097152) # ~2M tokens!
def test_estimate_cost(self, provider):
"""Test cost estimation."""
cost = provider.estimate_cost(
input_tokens=1000000,
output_tokens=500000,
model="gemini-2.0-flash",
)
assert cost is not None
# 1M input * $0.10 + 0.5M output * $0.40 = $0.10 + $0.20 = $0.30
assert abs(cost - 0.30) < 0.01
def test_openai_compatible_url(self):
"""Test OpenAI-compatible URL."""
url = GoogleProvider.get_openai_compatible_url("test-key")
assert "generativelanguage.googleapis.com" in url
class TestProviderFactoryFunctions:
"""Tests for provider factory functions."""
def test_create_ollama_provider(self):
"""Test creating Ollama provider."""
provider = create_ollama_provider()
assert provider.name == "ollama"
assert provider.base_url == "http://localhost:11434/v1"
def test_create_ollama_provider_custom_url(self):
"""Test creating Ollama provider with custom URL."""
provider = create_ollama_provider("http://192.168.1.100:11434/v1")
assert provider.base_url == "http://192.168.1.100:11434/v1"
def test_create_together_provider(self):
"""Test creating Together provider."""
provider = create_together_provider()
assert provider.name == "together"
assert "together.xyz" in provider.base_url
def test_create_groq_provider(self):
"""Test creating Groq provider."""
provider = create_groq_provider()
assert provider.name == "groq"
assert "groq.com" in provider.base_url
def test_create_vllm_provider(self):
"""Test creating vLLM provider."""
provider = create_vllm_provider("http://localhost:8000/v1")
assert provider.name == "vllm"
assert provider.base_url == "http://localhost:8000/v1"
def test_create_lmstudio_provider(self):
"""Test creating LM Studio provider."""
provider = create_lmstudio_provider()
assert provider.name == "lmstudio"
assert provider.base_url == "http://localhost:1234/v1"
def test_create_fireworks_and_anyscale_providers(self):
fireworks = create_fireworks_provider(api_key="fireworks-key")
anyscale = create_anyscale_provider(api_key="anyscale-key")
assert fireworks.name == "fireworks"
assert fireworks.base_url == "https://api.fireworks.ai/inference/v1"
assert fireworks.api_key == "fireworks-key"
assert anyscale.name == "anyscale"
assert anyscale.base_url == "https://api.endpoints.anyscale.com/v1"
assert anyscale.api_key == "anyscale-key"
class TestLiteLLMProvider:
"""Tests for LiteLLM provider."""
def test_is_litellm_available(self):
"""Test checking LiteLLM availability."""
result = is_litellm_available()
assert isinstance(result, bool)
def test_unavailable_litellm_paths(self, monkeypatch):
import headroom.providers.litellm as litellm_module
monkeypatch.setattr(litellm_module, "LITELLM_AVAILABLE", False)
assert litellm_module.is_litellm_available() is False
assert litellm_module.LiteLLMProvider.list_supported_providers() == []
with pytest.raises(RuntimeError, match="LiteLLM is required"):
litellm_module.LiteLLMTokenCounter("gpt-4o")
with pytest.raises(RuntimeError, match="LiteLLM is required"):
litellm_module.LiteLLMProvider()
def test_litellm_token_counter_fallback_paths(self, monkeypatch):
import headroom.providers.litellm as litellm_module
class DummyFallback:
def count_text(self, text: str) -> int:
return len(text.split())
monkeypatch.setattr(litellm_module, "LITELLM_AVAILABLE", True)
monkeypatch.setattr(
litellm_module,
"litellm_token_counter",
lambda **kwargs: (_ for _ in ()).throw(RuntimeError("boom")),
)
monkeypatch.setattr(litellm_module, "EstimatingTokenCounter", DummyFallback)
counter = litellm_module.LiteLLMTokenCounter("gpt-4o")
assert counter.count_text("") == 0
assert counter.count_text("one two three") == 3
assert counter.count_message({"content": "one two"}) == 6
assert counter.count_messages([]) == 0
assert counter.count_messages([{"content": "one two"}, {"content": "three"}]) == 14
def test_litellm_provider_info_and_cost_fallbacks(self, monkeypatch):
import headroom.providers.litellm as litellm_module
monkeypatch.setattr(litellm_module, "LITELLM_AVAILABLE", True)
monkeypatch.setattr(
litellm_module,
"litellm_get_model_info",
lambda model: {
"ctx-model": {"max_input_tokens": 64000},
"max-model": {"max_tokens": 32000},
"none-model": {"max_input_tokens": None, "max_output_tokens": None},
"output-model": {"max_output_tokens": 6000},
}[model],
)
monkeypatch.setattr(
litellm_module,
"litellm",
type(
"LiteLLM",
(),
{
"completion_cost": staticmethod(
lambda **kwargs: (
1.23
if kwargs["model"] == "priced-model"
else (_ for _ in ()).throw(RuntimeError("missing price"))
)
)
},
)(),
)
provider = litellm_module.LiteLLMProvider()
assert provider.get_context_limit("ctx-model") == 64000
assert provider.get_context_limit("max-model") == 32000
assert provider.get_context_limit("none-model") == 128000
assert provider.get_output_buffer("output-model", default=4000) == 4000
assert provider.get_output_buffer("none-model", default=2222) == 2222
assert provider.estimate_cost(1000, 1000, "priced-model") == 1.23
assert provider.estimate_cost(1000, 1000, "missing-price") is None
def test_litellm_provider_handles_info_exceptions_and_factory(self, monkeypatch):
import headroom.providers.litellm as litellm_module
monkeypatch.setattr(litellm_module, "LITELLM_AVAILABLE", True)
monkeypatch.setattr(
litellm_module,
"litellm_get_model_info",
lambda model: (_ for _ in ()).throw(RuntimeError("boom")),
)
provider = create_litellm_provider()
assert isinstance(provider, LiteLLMProvider)
assert provider.get_context_limit("gpt-4o") == 128000
assert provider.get_output_buffer("gpt-4o", default=3333) == 3333
@pytest.mark.skipif(
not is_litellm_available(),
reason="LiteLLM not installed",
)
def test_create_litellm_provider(self):
"""Test creating LiteLLM provider."""
from headroom.providers import create_litellm_provider
provider = create_litellm_provider()
assert provider.name == "litellm"
@pytest.mark.skipif(
not is_litellm_available(),
reason="LiteLLM not installed",
)
def test_litellm_supports_any_model(self):
"""Test LiteLLM supports any model."""
from headroom.providers import create_litellm_provider
provider = create_litellm_provider()
assert provider.supports_model("gpt-4o") is True
assert provider.supports_model("claude-3-sonnet") is True
assert provider.supports_model("any-model") is True
@pytest.mark.skipif(
not is_litellm_available(),
reason="LiteLLM not installed",
)
def test_litellm_list_providers(self):
"""Test listing LiteLLM providers."""
from headroom.providers import LiteLLMProvider
providers = LiteLLMProvider.list_supported_providers()
assert "openai" in providers
assert "anthropic" in providers
assert "ollama" in providers