test(models): cover ModelsDev Service with mocked HttpClient

Mocks HttpClient via HttpClient.makeWith and pre-populates the on-disk cache
to drive every code path: disk-hit, disk-empty fallback, single-flight
dedup, in-memory cache stickiness, refresh fetch, fresh/stale TTL skip,
and HTTP-error swallow.

Layer.fresh is required to defeat the process-global MemoMap so each test
gets its own cachedInvalidateWithTTL state.

Author: kitlangton

packages/opencode/test/provider/models.test.ts

@@ -0,0 +1,255 @@
+import { describe, expect, beforeEach, afterAll } from "bun:test"
+import { Effect, Layer, Ref } from "effect"
+import { HttpClient, HttpClientError, HttpClientResponse } from "effect/unstable/http"
+import { AppFileSystem } from "@opencode-ai/core/filesystem"
+import { Flag } from "@opencode-ai/core/flag/flag"
+import { Global } from "@opencode-ai/core/global"
+import { ModelsDev } from "../../src/provider/models"
+import { it } from "../lib/effect"
+import { rm, writeFile, utimes, mkdir } from "fs/promises"
+import path from "path"
+
+// test/preload.ts sets OPENCODE_MODELS_PATH to a static fixture and leaves
+// MODELS_FETCH enabled — both flags are captured at flag-module load time,
+// which is too early for env mutation to take effect. Mutate the resolved Flag
+// values directly; they're read inside Layer.effect when each test builds.
+Flag.OPENCODE_DISABLE_MODELS_FETCH = true
+Flag.OPENCODE_MODELS_PATH = undefined
+
+const cacheFile = path.join(Global.Path.cache, "models.json")
+
+const fixture: Record<string, ModelsDev.Provider> = {
+  acme: {
+    id: "acme",
+    name: "Acme",
+    env: ["ACME_API_KEY"],
+    models: {
+      "acme-1": {
+        id: "acme-1",
+        name: "Acme One",
+        release_date: "2026-01-01",
+        attachment: false,
+        reasoning: false,
+        temperature: true,
+        tool_call: true,
+        limit: { context: 128000, output: 8192 },
+      },
+    },
+  },
+}
+
+const fixture2: Record<string, ModelsDev.Provider> = {
+  beta: {
+    id: "beta",
+    name: "Beta",
+    env: ["BETA_API_KEY"],
+    models: {
+      "beta-1": {
+        id: "beta-1",
+        name: "Beta One",
+        release_date: "2026-02-01",
+        attachment: false,
+        reasoning: true,
+        temperature: false,
+        tool_call: false,
+        limit: { context: 64000, output: 4096 },
+      },
+    },
+  },
+}
+
+interface MockState {
+  body: string
+  status: number
+  calls: Array<{ url: string }>
+}
+
+const makeMockClient = (state: Ref.Ref<MockState>): HttpClient.HttpClient =>
+  HttpClient.makeWith(
+    Effect.fnUntraced(function* (requestEffect) {
+      const request = yield* requestEffect
+      yield* Ref.update(state, (s) => ({ ...s, calls: [...s.calls, { url: request.url }] }))
+      const s = yield* Ref.get(state)
+      return HttpClientResponse.fromWeb(request, new Response(s.body, { status: s.status }))
+    }),
+    Effect.succeed as HttpClient.HttpClient.Preprocess<HttpClientError.HttpClientError, never>,
+  )
+
+const buildLayer = (state: Ref.Ref<MockState>) =>
+  // Layer.fresh is required: ModelsDev.layer is a module-level Layer constant,
+  // and Effect.provide uses a process-global MemoMap by default — without fresh,
+  // every test would reuse the cachedInvalidateWithTTL state from the first run.
+  Layer.fresh(ModelsDev.layer).pipe(
+    Layer.provide(Layer.succeed(HttpClient.HttpClient, makeMockClient(state))),
+    Layer.provide(AppFileSystem.defaultLayer),
+  )
+
+const writeCache = (data: object, mtimeMs?: number) =>
+  Effect.promise(async () => {
+    await mkdir(Global.Path.cache, { recursive: true })
+    await writeFile(cacheFile, JSON.stringify(data))
+    if (mtimeMs !== undefined) {
+      const t = mtimeMs / 1000
+      await utimes(cacheFile, t, t)
+    }
+  })
+
+const provided = <A, E>(state: Ref.Ref<MockState>, eff: Effect.Effect<A, E, ModelsDev.Service>) =>
+  eff.pipe(Effect.provide(buildLayer(state)))
+
+beforeEach(async () => {
+  await rm(cacheFile, { force: true })
+})
+
+afterAll(async () => {
+  await rm(cacheFile, { force: true })
+})
+
+const initialState: MockState = {
+  body: JSON.stringify(fixture),
+  status: 200,
+  calls: [],
+}
+
+describe("ModelsDev Service", () => {
+  it.live("get() returns providers from disk when cache file exists", () =>
+    Effect.gen(function* () {
+      yield* writeCache(fixture)
+      const state = yield* Ref.make(initialState)
+      const result = yield* provided(
+        state,
+        ModelsDev.Service.use((s) => s.get()),
+      )
+      expect(result).toEqual(fixture)
+      const final = yield* Ref.get(state)
+      expect(final.calls).toEqual([])
+    }),
+  )
+
+  it.live("get() returns {} when disk empty and fetch disabled", () =>
+    Effect.gen(function* () {
+      const state = yield* Ref.make(initialState)
+      const result = yield* provided(
+        state,
+        ModelsDev.Service.use((s) => s.get()),
+      )
+      expect(result).toEqual({})
+      const final = yield* Ref.get(state)
+      expect(final.calls).toEqual([])
+    }),
+  )
+
+  it.live("get() is single-flight under concurrent calls", () =>
+    Effect.gen(function* () {
+      yield* writeCache(fixture)
+      const state = yield* Ref.make(initialState)
+      const results = yield* provided(
+        state,
+        Effect.gen(function* () {
+          const svc = yield* ModelsDev.Service
+          return yield* Effect.all(
+            [svc.get(), svc.get(), svc.get(), svc.get(), svc.get()],
+            { concurrency: "unbounded" },
+          )
+        }),
+      )
+      for (const result of results) expect(result).toEqual(fixture)
+    }),
+  )
+
+  it.live("get() caches across calls (later disk writes are ignored until invalidate)", () =>
+    Effect.gen(function* () {
+      yield* writeCache(fixture)
+      const state = yield* Ref.make(initialState)
+      const first = yield* provided(
+        state,
+        Effect.gen(function* () {
+          const svc = yield* ModelsDev.Service
+          const a = yield* svc.get()
+          // mutate disk between calls — cache should mask the change
+          yield* writeCache(fixture2)
+          const b = yield* svc.get()
+          return { a, b }
+        }),
+      )
+      expect(first.a).toEqual(fixture)
+      expect(first.b).toEqual(fixture)
+    }),
+  )
+
+  it.live("refresh(true) fetches via HttpClient and updates the cache", () =>
+    Effect.gen(function* () {
+      yield* writeCache(fixture)
+      const state = yield* Ref.make({ ...initialState, body: JSON.stringify(fixture2) })
+      const result = yield* provided(
+        state,
+        Effect.gen(function* () {
+          const svc = yield* ModelsDev.Service
+          const before = yield* svc.get()
+          yield* svc.refresh(true)
+          const after = yield* svc.get()
+          return { before, after }
+        }),
+      )
+      expect(result.before).toEqual(fixture)
+      expect(result.after).toEqual(fixture2)
+      const final = yield* Ref.get(state)
+      expect(final.calls.length).toBe(1)
+      expect(final.calls[0].url).toContain("/api.json")
+    }),
+  )
+
+  it.live("refresh(false) skips fetch when on-disk file is fresh", () =>
+    Effect.gen(function* () {
+      // Fresh: mtime within the 5-minute TTL.
+      yield* writeCache(fixture, Date.now() - 1000)
+      const state = yield* Ref.make({ ...initialState, body: JSON.stringify(fixture2) })
+      yield* provided(
+        state,
+        ModelsDev.Service.use((s) => s.refresh(false)),
+      )
+      const final = yield* Ref.get(state)
+      expect(final.calls).toEqual([])
+    }),
+  )
+
+  it.live("refresh(false) fetches when on-disk file is stale", () =>
+    Effect.gen(function* () {
+      // Stale: mtime 10 minutes ago, beyond the 5-minute TTL.
+      yield* writeCache(fixture, Date.now() - 10 * 60 * 1000)
+      const state = yield* Ref.make({ ...initialState, body: JSON.stringify(fixture2) })
+      const after = yield* provided(
+        state,
+        Effect.gen(function* () {
+          const svc = yield* ModelsDev.Service
+          yield* svc.refresh(false)
+          return yield* svc.get()
+        }),
+      )
+      const final = yield* Ref.get(state)
+      expect(final.calls.length).toBe(1)
+      expect(after).toEqual(fixture2)
+    }),
+  )
+
+  it.live("refresh swallows HTTP errors and leaves cache intact", () =>
+    Effect.gen(function* () {
+      yield* writeCache(fixture)
+      const state = yield* Ref.make({ ...initialState, status: 500, body: "boom" })
+      const result = yield* provided(
+        state,
+        Effect.gen(function* () {
+          const svc = yield* ModelsDev.Service
+          yield* svc.refresh(true)
+          return yield* svc.get()
+        }),
+      )
+      // refresh logged + ignored; the cache map is whatever loadFromDisk yields next.
+      // With the failing fetch the disk file is unchanged → still the original fixture.
+      expect(result).toEqual(fixture)
+      // withTransientReadRetry retries 5xx, so calls > 1 is expected.
+      const final = yield* Ref.get(state)
+      expect(final.calls.length).toBeGreaterThanOrEqual(1)
+    }),
+  )
+})