feat(llm): add provider-routed adapter composition

packages/opencode/test/provider/llm-bridge.test.ts

@@ -0,0 +1,172 @@
+import { describe, expect, test } from "bun:test"
+import { ProviderLLMBridge } from "../../src/provider/llm-bridge"
+import { ModelID, ProviderID } from "../../src/provider/schema"
+import { ProviderTest } from "../fake/provider"
+import type { Provider } from "../../src/provider"
+
+const model = (input: {
+  readonly id: string
+  readonly providerID: string
+  readonly npm: string
+  readonly apiID?: string
+  readonly apiURL?: string
+  readonly headers?: Record<string, string>
+  readonly options?: Record<string, unknown>
+  readonly reasoning?: boolean
+  readonly toolcall?: boolean
+  readonly variants?: Provider.Model["variants"]
+}): Provider.Model => {
+  const base = ProviderTest.model()
+  return ProviderTest.model({
+    id: ModelID.make(input.id),
+    providerID: ProviderID.make(input.providerID),
+    api: { id: input.apiID ?? input.id, url: input.apiURL ?? "", npm: input.npm },
+    capabilities: {
+      ...base.capabilities,
+      reasoning: input.reasoning ?? false,
+      toolcall: input.toolcall ?? true,
+    },
+    limit: { context: 128_000, output: 32_000 },
+    options: input.options ?? {},
+    headers: input.headers ?? {},
+    variants: input.variants ?? {},
+  })
+}
+
+const provider = (input: Partial<Provider.Info> & Pick<Provider.Info, "id">) =>
+  ProviderTest.info({ ...input, models: input.models ?? {} })
+
+describe("ProviderLLMBridge", () => {
+  test("maps OpenAI-style providers to Responses", () => {
+    const ref = ProviderLLMBridge.toModelRef({
+      provider: provider({ id: ProviderID.openai, key: "openai-key" }),
+      model: model({ id: "gpt-5", providerID: "openai", npm: "@ai-sdk/openai", reasoning: true, variants: { high: {} } }),
+    })
+
+    expect(ref).toMatchObject({
+      id: "gpt-5",
+      provider: "openai",
+      protocol: "openai-responses",
+      headers: { authorization: "Bearer openai-key" },
+      limits: { context: 128_000, output: 32_000 },
+    })
+    expect(ref?.capabilities.reasoning.efforts).toEqual(["high"])
+  })
+
+  test("maps Anthropic headers and cache capability", () => {
+    const ref = ProviderLLMBridge.toModelRef({
+      provider: provider({
+        id: ProviderID.anthropic,
+        key: "anthropic-key",
+        options: { headers: { "anthropic-beta": "fine-grained-tool-streaming-2025-05-14" } },
+      }),
+      model: model({ id: "claude-sonnet-4-5", providerID: "anthropic", npm: "@ai-sdk/anthropic" }),
+    })
+
+    expect(ref).toMatchObject({
+      protocol: "anthropic-messages",
+      headers: {
+        "x-api-key": "anthropic-key",
+        "anthropic-beta": "fine-grained-tool-streaming-2025-05-14",
+      },
+    })
+    expect(ref?.capabilities.cache).toMatchObject({ prompt: true, contentBlocks: true })
+  })
+
+  test("maps Gemini API keys", () => {
+    const ref = ProviderLLMBridge.toModelRef({
+      provider: provider({ id: ProviderID.make("google"), options: { apiKey: "google-key" } }),
+      model: model({ id: "gemini-2.5-flash", providerID: "google", npm: "@ai-sdk/google" }),
+    })
+
+    expect(ref).toMatchObject({
+      protocol: "gemini",
+      headers: { "x-goog-api-key": "google-key" },
+    })
+    expect(ref?.capabilities.tools.streamingInput).toBe(false)
+  })
+
+  test("maps known OpenAI-compatible provider families", () => {
+    const ref = ProviderLLMBridge.toModelRef({
+      provider: provider({ id: ProviderID.make("togetherai"), options: { apiKey: "together-key" } }),
+      model: model({
+        id: "llama",
+        apiID: "meta-llama/Llama-3.3-70B-Instruct-Turbo",
+        providerID: "togetherai",
+        npm: "@ai-sdk/togetherai",
+      }),
+    })
+
+    expect(ref).toMatchObject({
+      id: "meta-llama/Llama-3.3-70B-Instruct-Turbo",
+      provider: "togetherai",
+      protocol: "openai-compatible-chat",
+      baseURL: "https://api.together.xyz/v1",
+      headers: { authorization: "Bearer together-key" },
+    })
+  })
+
+  test("maps GitHub Copilot through its provider route", () => {
+    const ref = ProviderLLMBridge.toModelRef({
+      provider: provider({ id: ProviderID.make("github-copilot"), key: "copilot-key" }),
+      model: model({ id: "gpt-5", providerID: "github-copilot", npm: "@ai-sdk/github-copilot" }),
+    })
+
+    expect(ref).toMatchObject({
+      provider: "github-copilot",
+      protocol: "openai-responses",
+      headers: { authorization: "Bearer copilot-key" },
+    })
+  })
+
+  test("maps Azure through its provider route", () => {
+    const ref = ProviderLLMBridge.toModelRef({
+      provider: provider({ id: ProviderID.make("azure"), key: "azure-key", options: { useCompletionUrls: true } }),
+      model: model({ id: "gpt-4.1", providerID: "azure", npm: "@ai-sdk/azure" }),
+    })
+
+    expect(ref).toMatchObject({
+      provider: "azure",
+      protocol: "openai-chat",
+      headers: { authorization: "Bearer azure-key" },
+    })
+  })
+
+  test("keeps provider and model overrides ahead of defaults", () => {
+    const ref = ProviderLLMBridge.toModelRef({
+      provider: provider({
+        id: ProviderID.make("cerebras"),
+        key: "cerebras-key",
+        options: {
+          baseURL: "https://custom.cerebras.test/v1",
+          headers: { "X-Cerebras-3rd-Party-Integration": "opencode" },
+        },
+      }),
+      model: model({
+        id: "cerebras-model",
+        providerID: "cerebras",
+        npm: "@ai-sdk/cerebras",
+        headers: { "x-model-header": "1" },
+      }),
+    })
+
+    expect(ref).toMatchObject({
+      protocol: "openai-compatible-chat",
+      baseURL: "https://custom.cerebras.test/v1",
+      headers: {
+        authorization: "Bearer cerebras-key",
+        "X-Cerebras-3rd-Party-Integration": "opencode",
+        "x-model-header": "1",
+      },
+    })
+  })
+
+  test("leaves undecided provider packages unmapped", () => {
+    expect(
+      ProviderLLMBridge.toModelRef({
+        provider: provider({ id: ProviderID.make("mistral"), key: "mistral-key" }),
+        model: model({ id: "mistral-large", providerID: "mistral", npm: "@ai-sdk/mistral" }),
+      }),
+    ).toBeUndefined()
+  })
+})