Files
claude-code/packages/@ant/model-provider/src/shared/__tests__/openaiStreamAdapter.test.ts
claude-code-best ed61932748 fix: subtract cached_tokens from input_tokens in OpenAI stream adapter
OpenAI's prompt_tokens includes cached tokens, but Anthropic's
input_tokens semantic excludes them. The adapter was mapping
prompt_tokens → input_tokens verbatim, causing downstream code
(cache hit rate, cost, autocompact) to double-count.

Real-world impact: DeepSeek returns prompt_tokens=34097 with
cached_tokens=34048, displayed as 50% hit rate instead of 99.86%.

Co-Authored-By: glm-5.1 <zai-org@claude-code-best.win>
2026-05-22 21:58:33 +08:00

857 lines
27 KiB
TypeScript

import { describe, expect, test } from 'bun:test'
import type { ChatCompletionChunk } from 'openai/resources/chat/completions/completions.mjs'
import { adaptOpenAIStreamToAnthropic } from '../openaiStreamAdapter.js'
/** Helper to create a mock async iterable from chunk array */
function mockStream(
chunks: ChatCompletionChunk[],
): AsyncIterable<ChatCompletionChunk> {
return {
[Symbol.asyncIterator]() {
let i = 0
return {
async next() {
if (i >= chunks.length) return { done: true, value: undefined }
return { done: false, value: chunks[i++] }
},
}
},
}
}
/** Create a minimal ChatCompletionChunk */
function makeChunk(
overrides: Partial<ChatCompletionChunk> & any = {},
): ChatCompletionChunk {
return {
id: 'chatcmpl-test',
object: 'chat.completion.chunk',
created: 1234567890,
model: 'gpt-4o',
choices: [],
...overrides,
} as ChatCompletionChunk
}
/** Collect all emitted Anthropic events from the stream adapter for assertion */
async function collectEvents(chunks: ChatCompletionChunk[]) {
const events: any[] = []
for await (const event of adaptOpenAIStreamToAnthropic(
mockStream(chunks),
'gpt-4o',
)) {
events.push(event)
}
return events
}
describe('adaptOpenAIStreamToAnthropic', () => {
test('emits message_start on first chunk', async () => {
const events = await collectEvents([
makeChunk({
choices: [
{
index: 0,
delta: { role: 'assistant', content: '' },
finish_reason: null,
},
],
}),
makeChunk({
choices: [
{
index: 0,
delta: { content: 'hello' },
finish_reason: null,
},
],
}),
makeChunk({
choices: [
{
index: 0,
delta: {},
finish_reason: 'stop',
},
],
usage: { prompt_tokens: 10, completion_tokens: 5, total_tokens: 15 },
}),
])
expect(events[0].type).toBe('message_start')
expect(events[0].message.role).toBe('assistant')
expect(events[0].message.model).toBe('gpt-4o')
})
test('converts text content stream', async () => {
const events = await collectEvents([
makeChunk({
choices: [
{ index: 0, delta: { content: 'Hello' }, finish_reason: null },
],
}),
makeChunk({
choices: [
{ index: 0, delta: { content: ' world' }, finish_reason: null },
],
}),
makeChunk({
choices: [{ index: 0, delta: {}, finish_reason: 'stop' }],
}),
])
const types = events.map(e => e.type)
expect(types).toContain('message_start')
expect(types).toContain('content_block_start')
expect(types.filter(t => t === 'content_block_delta').length).toBe(2)
expect(types).toContain('content_block_stop')
expect(types).toContain('message_delta')
expect(types).toContain('message_stop')
const textDeltas = events.filter(
e => e.type === 'content_block_delta',
) as any[]
expect(textDeltas[0].delta.text).toBe('Hello')
expect(textDeltas[1].delta.text).toBe(' world')
})
test('converts tool_calls stream', async () => {
const events = await collectEvents([
makeChunk({
choices: [
{
index: 0,
delta: {
tool_calls: [
{
index: 0,
id: 'call_abc',
type: 'function',
function: { name: 'bash', arguments: '' },
},
],
},
finish_reason: null,
},
],
}),
makeChunk({
choices: [
{
index: 0,
delta: {
tool_calls: [
{
index: 0,
function: { arguments: '{"comm' },
},
],
},
finish_reason: null,
},
],
}),
makeChunk({
choices: [
{
index: 0,
delta: {
tool_calls: [
{
index: 0,
function: { arguments: 'and":"ls"}' },
},
],
},
finish_reason: null,
},
],
}),
makeChunk({
choices: [{ index: 0, delta: {}, finish_reason: 'tool_calls' }],
}),
])
const blockStart = events.find(e => e.type === 'content_block_start') as any
expect(blockStart.content_block.type).toBe('tool_use')
expect(blockStart.content_block.name).toBe('bash')
const jsonDeltas = events.filter(
e =>
e.type === 'content_block_delta' && e.delta.type === 'input_json_delta',
) as any[]
const fullArgs = jsonDeltas.map(d => d.delta.partial_json).join('')
expect(fullArgs).toBe('{"command":"ls"}')
})
test('maps finish_reason stop to end_turn', async () => {
const events = await collectEvents([
makeChunk({
choices: [{ index: 0, delta: { content: 'hi' }, finish_reason: null }],
}),
makeChunk({
choices: [{ index: 0, delta: {}, finish_reason: 'stop' }],
}),
])
const msgDelta = events.find(e => e.type === 'message_delta') as any
expect(msgDelta.delta.stop_reason).toBe('end_turn')
})
test('forces tool_use stop_reason when tool_calls present but finish_reason is stop', async () => {
// Some backends (e.g., certain OpenAI-compatible endpoints) incorrectly
// return finish_reason "stop" when they actually made tool calls.
const events = await collectEvents([
makeChunk({
choices: [
{
index: 0,
delta: {
tool_calls: [
{
index: 0,
id: 'call_1',
function: { name: 'bash', arguments: '{"cmd":"ls"}' },
},
],
},
finish_reason: null,
},
],
}),
makeChunk({
choices: [{ index: 0, delta: {}, finish_reason: 'stop' }],
}),
])
const msgDelta = events.find(e => e.type === 'message_delta') as any
expect(msgDelta.delta.stop_reason).toBe('tool_use')
})
test('maps finish_reason tool_calls to tool_use', async () => {
const events = await collectEvents([
makeChunk({
choices: [
{
index: 0,
delta: {
tool_calls: [
{
index: 0,
id: 'call_1',
function: { name: 'bash', arguments: '{}' },
},
],
},
finish_reason: null,
},
],
}),
makeChunk({
choices: [{ index: 0, delta: {}, finish_reason: 'tool_calls' }],
}),
])
const msgDelta = events.find(e => e.type === 'message_delta') as any
expect(msgDelta.delta.stop_reason).toBe('tool_use')
})
test('maps finish_reason length to max_tokens', async () => {
const events = await collectEvents([
makeChunk({
choices: [
{ index: 0, delta: { content: 'truncated' }, finish_reason: null },
],
}),
makeChunk({
choices: [{ index: 0, delta: {}, finish_reason: 'length' }],
}),
])
const msgDelta = events.find(e => e.type === 'message_delta') as any
expect(msgDelta.delta.stop_reason).toBe('max_tokens')
})
test('handles mixed text and tool_calls', async () => {
const events = await collectEvents([
makeChunk({
choices: [
{ index: 0, delta: { content: 'Thinking...' }, finish_reason: null },
],
}),
makeChunk({
choices: [
{
index: 0,
delta: {
tool_calls: [
{
index: 0,
id: 'call_1',
function: { name: 'grep', arguments: '{"p":"test"}' },
},
],
},
finish_reason: null,
},
],
}),
makeChunk({
choices: [{ index: 0, delta: {}, finish_reason: 'tool_calls' }],
}),
])
const blockStarts = events.filter(
e => e.type === 'content_block_start',
) as any[]
expect(blockStarts.length).toBe(2)
expect(blockStarts[0].content_block.type).toBe('text')
expect(blockStarts[1].content_block.type).toBe('tool_use')
})
})
describe('thinking support (reasoning_content)', () => {
test('converts reasoning_content to thinking block', async () => {
const events = await collectEvents([
makeChunk({
choices: [
{
index: 0,
delta: { reasoning_content: 'Let me analyze this...' },
finish_reason: null,
},
],
}),
makeChunk({
choices: [
{
index: 0,
delta: { reasoning_content: ' step by step.' },
finish_reason: null,
},
],
}),
makeChunk({
choices: [{ index: 0, delta: {}, finish_reason: 'stop' }],
}),
])
// Should have a thinking content block
const blockStart = events.find(e => e.type === 'content_block_start') as any
expect(blockStart.content_block.type).toBe('thinking')
expect(blockStart.content_block.signature).toBe('')
// Should have thinking_delta events
const thinkingDeltas = events.filter(
e =>
e.type === 'content_block_delta' && e.delta.type === 'thinking_delta',
) as any[]
expect(thinkingDeltas.length).toBe(2)
expect(thinkingDeltas[0].delta.thinking).toBe('Let me analyze this...')
expect(thinkingDeltas[1].delta.thinking).toBe(' step by step.')
})
test('converts reasoning then content (DeepSeek-style)', async () => {
const events = await collectEvents([
makeChunk({
choices: [
{
index: 0,
delta: { reasoning_content: 'Thinking about the answer...' },
finish_reason: null,
},
],
}),
makeChunk({
choices: [
{
index: 0,
delta: { content: 'Here is my answer.' },
finish_reason: null,
},
],
}),
makeChunk({
choices: [{ index: 0, delta: {}, finish_reason: 'stop' }],
}),
])
// Should have two content blocks: thinking + text
const blockStarts = events.filter(
e => e.type === 'content_block_start',
) as any[]
expect(blockStarts.length).toBe(2)
expect(blockStarts[0].content_block.type).toBe('thinking')
expect(blockStarts[1].content_block.type).toBe('text')
// Thinking block should be closed before text block starts
const blockStops = events.filter(
e => e.type === 'content_block_stop',
) as any[]
expect(blockStops[0].index).toBe(0) // thinking block closed at index 0
expect(blockStarts[1].index).toBe(1) // text block starts at index 1
// Verify text delta
const textDelta = events.find(
e => e.type === 'content_block_delta' && e.delta.type === 'text_delta',
) as any
expect(textDelta.delta.text).toBe('Here is my answer.')
})
test('handles reasoning then tool_calls', async () => {
const events = await collectEvents([
makeChunk({
choices: [
{
index: 0,
delta: { reasoning_content: 'I need to run a command.' },
finish_reason: null,
},
],
}),
makeChunk({
choices: [
{
index: 0,
delta: {
tool_calls: [
{
index: 0,
id: 'call_1',
function: { name: 'bash', arguments: '{"c":"ls"}' },
},
],
},
finish_reason: null,
},
],
}),
makeChunk({
choices: [{ index: 0, delta: {}, finish_reason: 'tool_calls' }],
}),
])
const blockStarts = events.filter(
e => e.type === 'content_block_start',
) as any[]
expect(blockStarts.length).toBe(2)
expect(blockStarts[0].content_block.type).toBe('thinking')
expect(blockStarts[1].content_block.type).toBe('tool_use')
})
test('opens thinking block on empty reasoning_content (DeepSeek v4 direct-answer)', async () => {
// DeepSeek v4 thinking mode sometimes streams reasoning_content: ""
// before answering directly. We must still open a thinking block so the
// resulting assistant message carries an (empty) thinking block — that
// round-trips back as reasoning_content: "" in the next request,
// satisfying DeepSeek's requirement (see issue #399).
const events = await collectEvents([
makeChunk({
choices: [
{
index: 0,
delta: { reasoning_content: '' },
finish_reason: null,
},
],
}),
makeChunk({
choices: [
{
index: 0,
delta: { content: 'Direct answer.' },
finish_reason: null,
},
],
}),
makeChunk({
choices: [{ index: 0, delta: {}, finish_reason: 'stop' }],
}),
])
// A thinking block was opened (and closed before the text block starts)
const blockStarts = events.filter(
e => e.type === 'content_block_start',
) as any[]
expect(blockStarts.length).toBe(2)
expect(blockStarts[0].content_block.type).toBe('thinking')
expect(blockStarts[0].content_block.thinking).toBe('')
expect(blockStarts[1].content_block.type).toBe('text')
// No empty thinking_delta should be emitted — the empty string is
// already conveyed by the thinking block's initial value.
const thinkingDeltas = events.filter(
e =>
e.type === 'content_block_delta' && e.delta.type === 'thinking_delta',
)
expect(thinkingDeltas.length).toBe(0)
})
test('thinking block index is 0, text block index is 1', async () => {
const events = await collectEvents([
makeChunk({
choices: [
{
index: 0,
delta: { reasoning_content: 'reason' },
finish_reason: null,
},
],
}),
makeChunk({
choices: [
{
index: 0,
delta: { content: 'answer' },
finish_reason: null,
},
],
}),
makeChunk({
choices: [{ index: 0, delta: {}, finish_reason: 'stop' }],
}),
])
const blockStarts = events.filter(
e => e.type === 'content_block_start',
) as any[]
expect(blockStarts[0].index).toBe(0)
expect(blockStarts[1].index).toBe(1)
})
})
describe('prompt caching support', () => {
test('maps cached_tokens to cache_read_input_tokens', async () => {
const events = await collectEvents([
makeChunk({
choices: [
{
index: 0,
delta: { content: 'hi' },
finish_reason: null,
},
],
usage: {
prompt_tokens: 1000,
completion_tokens: 0,
total_tokens: 1000,
prompt_tokens_details: { cached_tokens: 800 },
} as any,
}),
makeChunk({
choices: [{ index: 0, delta: {}, finish_reason: 'stop' }],
usage: {
prompt_tokens: 1000,
completion_tokens: 50,
total_tokens: 1050,
prompt_tokens_details: { cached_tokens: 800 },
} as any,
}),
])
const msgStart = events.find(e => e.type === 'message_start') as any
expect(msgStart.message.usage.cache_read_input_tokens).toBe(800)
// input_tokens = prompt_tokens - cached_tokens = 1000 - 800 = 200
expect(msgStart.message.usage.input_tokens).toBe(200)
})
test('defaults cache_read_input_tokens to 0 when no cached_tokens', async () => {
const events = await collectEvents([
makeChunk({
choices: [{ index: 0, delta: { content: 'hi' }, finish_reason: null }],
usage: { prompt_tokens: 100, completion_tokens: 0, total_tokens: 100 },
}),
makeChunk({
choices: [{ index: 0, delta: {}, finish_reason: 'stop' }],
}),
])
const msgStart = events.find(e => e.type === 'message_start') as any
expect(msgStart.message.usage.cache_read_input_tokens).toBe(0)
expect(msgStart.message.usage.cache_creation_input_tokens).toBe(0)
})
test('updates cached_tokens from later chunks', async () => {
const events = await collectEvents([
makeChunk({
choices: [{ index: 0, delta: { content: 'hi' }, finish_reason: null }],
usage: {
prompt_tokens: 500,
completion_tokens: 0,
total_tokens: 500,
} as any,
}),
makeChunk({
choices: [{ index: 0, delta: {}, finish_reason: 'stop' }],
usage: {
prompt_tokens: 500,
completion_tokens: 10,
total_tokens: 510,
prompt_tokens_details: { cached_tokens: 300 },
} as any,
}),
])
const msgStart = events.find(e => e.type === 'message_start') as any
// First chunk had no cached_tokens, so initially 0
// But the message_start usage reflects the first chunk's data
expect(msgStart.message.usage.cache_read_input_tokens).toBe(0)
expect(msgStart.message.usage.input_tokens).toBe(500)
})
test('captures output_tokens and input_tokens from trailing chunk sent after finish_reason', async () => {
// Many OpenAI-compatible endpoints (e.g. DeepSeek) send usage in a separate
// final chunk AFTER the finish_reason chunk, with choices: [].
// message_delta must carry both input_tokens and output_tokens so that
// queryModelOpenAI's spread can override the zeros from message_start — which is
// emitted before the trailing chunk and always has input_tokens=0.
const events = await collectEvents([
makeChunk({
choices: [
{ index: 0, delta: { content: 'hello' }, finish_reason: null },
],
}),
// finish_reason chunk — usage not yet available
makeChunk({
choices: [{ index: 0, delta: {}, finish_reason: 'stop' }],
}),
// trailing usage-only chunk (choices: [])
makeChunk({
choices: [],
usage: { prompt_tokens: 123, completion_tokens: 45, total_tokens: 168 },
}),
])
// message_start emits on the first chunk before trailing usage arrives
const msgStart = events.find(e => e.type === 'message_start') as any
expect(msgStart.message.usage.input_tokens).toBe(0)
// message_delta is emitted after stream loop ends with final real values
const msgDelta = events.find(e => e.type === 'message_delta') as any
expect(msgDelta.usage.input_tokens).toBe(123)
expect(msgDelta.usage.output_tokens).toBe(45)
expect(msgDelta.delta.stop_reason).toBe('end_turn')
})
test('captures input_tokens from trailing chunk (used by tokenCountWithEstimation for autocompact)', async () => {
// input_tokens is the dominant term in tokenCountWithEstimation. Without it,
// getTokenCountFromUsage returns only output_tokens (~100-700), which is far below
// the autocompact threshold (~33k), so compaction never fires.
const events = await collectEvents([
makeChunk({
choices: [
{ index: 0, delta: { content: 'answer' }, finish_reason: null },
],
}),
makeChunk({
choices: [{ index: 0, delta: {}, finish_reason: 'stop' }],
}),
makeChunk({
choices: [],
usage: {
prompt_tokens: 800,
completion_tokens: 200,
total_tokens: 1000,
},
}),
])
const msgDelta = events.find(e => e.type === 'message_delta') as any
expect(msgDelta.usage.input_tokens).toBe(800)
expect(msgDelta.usage.output_tokens).toBe(200)
})
test('trailing usage chunk with tool_calls: stop_reason stays tool_use', async () => {
// Verifies that deferring message_delta does not break stop_reason mapping
// when the model made tool calls and usage arrives in a trailing chunk.
const events = await collectEvents([
makeChunk({
choices: [
{
index: 0,
delta: {
tool_calls: [
{
index: 0,
id: 'call_x',
function: { name: 'bash', arguments: '{"cmd":"ls"}' },
},
],
},
finish_reason: null,
},
],
}),
makeChunk({
choices: [{ index: 0, delta: {}, finish_reason: 'tool_calls' }],
}),
// trailing usage-only chunk
makeChunk({
choices: [],
usage: { prompt_tokens: 500, completion_tokens: 30, total_tokens: 530 },
}),
])
const msgDelta = events.find(e => e.type === 'message_delta') as any
expect(msgDelta.delta.stop_reason).toBe('tool_use')
expect(msgDelta.usage.output_tokens).toBe(30)
})
test('message_delta always comes before message_stop', async () => {
// Verifies event ordering is preserved after deferring to post-loop emission.
const events = await collectEvents([
makeChunk({
choices: [{ index: 0, delta: { content: 'x' }, finish_reason: null }],
}),
makeChunk({ choices: [{ index: 0, delta: {}, finish_reason: 'stop' }] }),
makeChunk({
choices: [],
usage: { prompt_tokens: 10, completion_tokens: 5, total_tokens: 15 },
}),
])
const types = events.map(e => e.type)
const deltaIdx = types.lastIndexOf('message_delta')
const stopIdx = types.lastIndexOf('message_stop')
expect(deltaIdx).toBeGreaterThanOrEqual(0)
expect(stopIdx).toBeGreaterThan(deltaIdx)
})
// ── cache_read_input_tokens in message_delta (the core bug fix) ──────────
test('message_delta carries cache_read_input_tokens from trailing usage chunk', async () => {
// Real-world case: DeepSeek-V3 returns cached_tokens=19904
// in a trailing chunk with choices:[]. Previously message_delta only carried
// input_tokens and output_tokens, so cache_read_input_tokens stayed 0 after
// queryModelOpenAI's spread — even though cachedTokens was captured internally.
const events = await collectEvents([
makeChunk({
choices: [
{ index: 0, delta: { content: 'answer' }, finish_reason: null },
],
}),
makeChunk({
choices: [{ index: 0, delta: {}, finish_reason: 'stop' }],
}),
// trailing usage chunk matching the observed server response format
makeChunk({
choices: [],
usage: {
prompt_tokens: 30011,
completion_tokens: 190,
total_tokens: 30201,
prompt_tokens_details: { audio_tokens: 0, cached_tokens: 19904 },
} as any,
}),
])
// message_start is emitted before trailing chunk — cache fields are 0
const msgStart = events.find(e => e.type === 'message_start') as any
expect(msgStart.message.usage.cache_read_input_tokens).toBe(0)
// message_delta carries the real values from the trailing chunk
const msgDelta = events.find(e => e.type === 'message_delta') as any
// input_tokens = prompt_tokens - cached_tokens = 30011 - 19904 = 10107
expect(msgDelta.usage.input_tokens).toBe(10107)
expect(msgDelta.usage.output_tokens).toBe(190)
expect(msgDelta.usage.cache_read_input_tokens).toBe(19904)
expect(msgDelta.usage.cache_creation_input_tokens).toBe(0)
})
test('cache_read_input_tokens=0 in message_delta when cached_tokens is absent', async () => {
// Non-caching requests should still have the field present and zero.
const events = await collectEvents([
makeChunk({
choices: [{ index: 0, delta: { content: 'hi' }, finish_reason: null }],
}),
makeChunk({
choices: [{ index: 0, delta: {}, finish_reason: 'stop' }],
}),
makeChunk({
choices: [],
usage: { prompt_tokens: 100, completion_tokens: 20, total_tokens: 120 },
}),
])
const msgDelta = events.find(e => e.type === 'message_delta') as any
expect(msgDelta.usage.cache_read_input_tokens).toBe(0)
expect(msgDelta.usage.cache_creation_input_tokens).toBe(0)
})
test('cache_read_input_tokens=0 in message_delta when cached_tokens is 0', async () => {
// Explicit cached_tokens:0 should not be treated differently from absent.
const events = await collectEvents([
makeChunk({
choices: [{ index: 0, delta: { content: 'hi' }, finish_reason: null }],
}),
makeChunk({
choices: [{ index: 0, delta: {}, finish_reason: 'stop' }],
}),
makeChunk({
choices: [],
usage: {
prompt_tokens: 500,
completion_tokens: 50,
total_tokens: 550,
prompt_tokens_details: { cached_tokens: 0 },
} as any,
}),
])
const msgDelta = events.find(e => e.type === 'message_delta') as any
expect(msgDelta.usage.cache_read_input_tokens).toBe(0)
})
test('cache_read_input_tokens updated when cached_tokens arrives in same chunk as finish_reason', async () => {
// Some endpoints send usage in the finish_reason chunk instead of a trailing chunk.
const events = await collectEvents([
makeChunk({
choices: [
{ index: 0, delta: { content: 'result' }, finish_reason: null },
],
}),
makeChunk({
choices: [{ index: 0, delta: {}, finish_reason: 'stop' }],
usage: {
prompt_tokens: 2000,
completion_tokens: 100,
total_tokens: 2100,
prompt_tokens_details: { cached_tokens: 1500 },
} as any,
}),
])
const msgDelta = events.find(e => e.type === 'message_delta') as any
expect(msgDelta.usage.cache_read_input_tokens).toBe(1500)
// input_tokens = prompt_tokens - cached_tokens = 2000 - 1500 = 500
expect(msgDelta.usage.input_tokens).toBe(500)
expect(msgDelta.usage.output_tokens).toBe(100)
})
test('subtracts cached_tokens from input_tokens to match Anthropic semantic', async () => {
// Anthropic's input_tokens = non-cached tokens only.
// OpenAI's prompt_tokens = total input including cached.
// The adapter must subtract: input_tokens = prompt_tokens - cached_tokens.
const events = await collectEvents([
makeChunk({
choices: [{ index: 0, delta: { content: 'hi' }, finish_reason: null }],
}),
makeChunk({
choices: [{ index: 0, delta: {}, finish_reason: 'stop' }],
usage: {
prompt_tokens: 34097,
completion_tokens: 30,
total_tokens: 34127,
prompt_tokens_details: { cached_tokens: 34048 },
} as any,
}),
])
const msgDelta = events.find(e => e.type === 'message_delta') as any
// input_tokens = 34097 - 34048 = 49 (non-cached input only)
expect(msgDelta.usage.input_tokens).toBe(49)
expect(msgDelta.usage.cache_read_input_tokens).toBe(34048)
expect(msgDelta.usage.output_tokens).toBe(30)
})
})