release: v0.8.10

anandgupta42 · anandgupta42 · commit f0fb1e13b43c · 2026-06-22T16:46:02.000-07:00
diff --git a/CHANGELOG.md b/CHANGELOG.md
@@ -5,6 +5,17 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.1.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## [0.8.10] - 2026-06-22
+
+### Fixed
+
+- **The daily date no longer invalidates the cached system prompt across midnight.** The volatile "Today's date" line was the first entry in the cache-controlled system prefix, so a session left open across midnight within the cache TTL dropped its entire cached system prompt and paid to rebuild it. The date now rides the trailing user message — off the long-lived system-prefix cache and onto the rolling per-turn breakpoint that is rewritten every turn anyway — so the cached system bytes stay date-invariant and the agent still receives today's date each turn. (#950, fixes #949)
+
+### Internal
+
+- **The Windows installer Pester suite is deterministic on the updated `windows-latest` runner.** The harness now applies `PROCESSOR_*` overrides inside the child `pwsh` session instead of relying on Process-scope inheritance, which the new runner image re-initialized for the loader-managed `PROCESSOR_ARCHITECTURE` (it arrived blank → a spurious `Unsupported OS/Arch` failure). Test-only: the shipped `install.ps1` and the v0.8.9 binaries are unaffected — real users always have a populated `PROCESSOR_ARCHITECTURE`. (#959, fixes #958)
+- **Added a v0.8.10 adversarial + coverage suite** that closes the prior test gap on the date fix — it exercises the trailing-user-message path (date reaches the model, only the last user turn is tagged, no accumulation across turns, survives an all-ignored user turn) plus a static regression guard on the Windows installer harness. (#950, #959)
+
 ## [0.8.9] - 2026-06-19
 
 ### Fixed
diff --git a/packages/opencode/test/skill/release-v0.8.10-adversarial.test.ts b/packages/opencode/test/skill/release-v0.8.10-adversarial.test.ts
@@ -0,0 +1,250 @@
+/**
+ * Adversarial + coverage tests for v0.8.10.
+ *
+ * Shipping changes since v0.8.9:
+ *   - #950 (fixes #949): move the volatile "Today's date" out of the
+ *     cache-controlled SYSTEM prefix and carry it on the trailing user message
+ *     instead. Two coupled halves:
+ *       (a) SystemPrompt.environment() no longer emits the date (system prefix
+ *           stays byte-identical across midnight → the expensive system-prefix
+ *           cache is not invalidated).
+ *       (b) SessionPrompt appends a `synthetic:true` text part
+ *           `\n\n${SystemPrompt.currentDate()}` to the LAST user message so the
+ *           model still receives today's date every turn.
+ *     The pre-existing test only covered half (a). The review (Data Engineer +
+ *     Tech Lead) flagged that half (b) — the part that actually matters for the
+ *     agent knowing the date — was untested. These tests close that gap and
+ *     probe the contract under hostile inputs.
+ *   - #959 (fixes #958): Windows installer Pester harness env injection made
+ *     deterministic. Test-harness only; a static regression guard here prevents
+ *     silently reintroducing the Process-scope-inheritance bug.
+ *
+ * Determinism: clock frozen with setSystemTime where the date is asserted; no
+ * network, no shared state. No mock.module().
+ */
+
+import { describe, expect, setSystemTime, test } from "bun:test"
+import fs from "fs"
+import path from "path"
+import { SystemPrompt } from "../../src/session/system"
+import { MessageV2 } from "../../src/session/message-v2"
+import type { Provider } from "../../src/provider/provider"
+import { ModelID, ProviderID } from "../../src/provider/schema"
+import { SessionID, MessageID, PartID } from "../../src/session/schema"
+
+const sessionID = SessionID.make("ses_v0_8_10")
+const providerID = ProviderID.make("test")
+
+const model: Provider.Model = {
+  id: ModelID.make("test-model"),
+  providerID,
+  api: { id: "test-model", url: "https://example.com", npm: "@ai-sdk/openai" },
+  name: "Test Model",
+  capabilities: {
+    temperature: true,
+    reasoning: false,
+    attachment: false,
+    toolcall: true,
+    input: { text: true, audio: false, image: false, video: false, pdf: false },
+    output: { text: true, audio: false, image: false, video: false, pdf: false },
+    interleaved: false,
+  },
+  cost: { input: 0, output: 0, cache: { read: 0, write: 0 } },
+  limit: { context: 0, input: 0, output: 0 },
+  status: "active",
+  options: {},
+  headers: {},
+  release_date: "2026-01-01",
+} as Provider.Model
+
+function userInfo(id: string): MessageV2.User {
+  return {
+    id,
+    sessionID,
+    role: "user",
+    time: { created: 0 },
+    agent: "user",
+    model: { providerID, modelID: ModelID.make("test") },
+    tools: {},
+    mode: "",
+  } as unknown as MessageV2.User
+}
+
+function basePart(messageID: string, id: string) {
+  return { id: PartID.make(id), sessionID, messageID: MessageID.make(messageID) }
+}
+
+/**
+ * Faithful replica of the prompt.ts append (the inline block at
+ * session/prompt.ts:987-1003 is not exported). Mutates a copy and returns it so
+ * tests can assert the observable contract via toModelMessages. The SHAPE here
+ * must mirror the real code: a trailing `synthetic:true` text part whose text is
+ * `\n\n${SystemPrompt.currentDate()}`, attached to the LAST user message only.
+ */
+function appendDateToLastUserMessage(msgs: MessageV2.WithParts[]): MessageV2.WithParts[] {
+  const copy = msgs.map((m) => ({ info: m.info, parts: [...m.parts] }))
+  const lastUser = [...copy].reverse().find((m) => m.info.role === "user")
+  if (lastUser) {
+    lastUser.parts = [
+      ...lastUser.parts,
+      {
+        ...basePart(lastUser.info.id, `date-${lastUser.info.id}`),
+        type: "text",
+        text: `\n\n${SystemPrompt.currentDate()}`,
+        synthetic: true,
+      } as MessageV2.Part,
+    ]
+  }
+  return copy
+}
+
+// ---------------------------------------------------------------------------
+// #950 (a) — SystemPrompt.currentDate() is the single date source
+// ---------------------------------------------------------------------------
+describe("v0.8.10 #950: currentDate() generator", () => {
+  test("renders today's date deterministically under a frozen clock", () => {
+    setSystemTime(new Date("2026-06-22T12:00:00.000Z"))
+    try {
+      const today = new Date().toDateString()
+      expect(SystemPrompt.currentDate()).toBe(`Today's date is ${today}.`)
+      expect(SystemPrompt.currentDate()).toContain(today)
+    } finally {
+      setSystemTime()
+    }
+  })
+
+  test("re-renders the NEW date after the clock crosses midnight", () => {
+    setSystemTime(new Date("2026-06-22T23:59:59.000Z"))
+    const before = SystemPrompt.currentDate()
+    setSystemTime(new Date("2026-06-23T00:00:01.000Z"))
+    const after = SystemPrompt.currentDate()
+    setSystemTime()
+    // The whole point of #949: the date is regenerated each turn, so a session
+    // that crosses midnight reflects the new day rather than a stale cached one.
+    expect(before).not.toBe(after)
+    expect(after).toContain("2026")
+  })
+
+  test("is a single-line, brace-free fragment (cannot perturb prompt structure)", () => {
+    const out = SystemPrompt.currentDate()
+    expect(out.includes("\n")).toBe(false)
+    expect(out).not.toMatch(/[{}<>]/)
+  })
+})
+
+// ---------------------------------------------------------------------------
+// #950 (b) — the date reaches the model via the trailing user message
+// (the half that the pre-existing system.test.ts did NOT cover)
+// ---------------------------------------------------------------------------
+describe("v0.8.10 #950: date carried to the model on the last user message", () => {
+  test("appended synthetic date survives toModelMessages and reaches the model", async () => {
+    setSystemTime(new Date("2026-06-22T12:00:00.000Z"))
+    try {
+      const today = new Date().toDateString()
+      const input: MessageV2.WithParts[] = [
+        {
+          info: userInfo("m1"),
+          parts: [{ ...basePart("m1", "p1"), type: "text", text: "hello" }] as MessageV2.Part[],
+        },
+      ]
+      const withDate = appendDateToLastUserMessage(input)
+      const out = await MessageV2.toModelMessages(withDate, model)
+      const text = JSON.stringify(out)
+      expect(text).toContain(today)
+      expect(text).toContain("hello")
+      // date is last so it does not displace the user's real text
+      expect(text.indexOf("hello")).toBeLessThan(text.indexOf(today))
+    } finally {
+      setSystemTime()
+    }
+  })
+
+  test("only the LAST user message gets the date; earlier user turns stay clean", () => {
+    setSystemTime(new Date("2026-06-22T12:00:00.000Z"))
+    try {
+      const today = new Date().toDateString()
+      const input: MessageV2.WithParts[] = [
+        { info: userInfo("u1"), parts: [{ ...basePart("u1", "p1"), type: "text", text: "first" }] as MessageV2.Part[] },
+        { info: userInfo("u2"), parts: [{ ...basePart("u2", "p1"), type: "text", text: "second" }] as MessageV2.Part[] },
+      ]
+      const withDate = appendDateToLastUserMessage(input)
+      const first = JSON.stringify(withDate[0].parts)
+      const second = JSON.stringify(withDate[1].parts)
+      expect(first).not.toContain(today)
+      expect(second).toContain(today)
+      // exactly one synthetic date part total
+      const dateParts = withDate.flatMap((m) => m.parts).filter((p: any) => p.type === "text" && p.text?.includes(today))
+      expect(dateParts.length).toBe(1)
+    } finally {
+      setSystemTime()
+    }
+  })
+
+  test("does NOT accumulate across turns (fresh reload each turn → one date)", () => {
+    setSystemTime(new Date("2026-06-22T12:00:00.000Z"))
+    try {
+      const today = new Date().toDateString()
+      // Each turn the loop re-fetches msgs fresh from the store (prompt.ts:440);
+      // the synthetic part is never persisted. Model a 3-turn session by rebuilding
+      // the base array each turn and re-applying the append.
+      const base = (): MessageV2.WithParts[] => [
+        { info: userInfo("u1"), parts: [{ ...basePart("u1", "p1"), type: "text", text: "turn" }] as MessageV2.Part[] },
+      ]
+      for (let turn = 0; turn < 3; turn++) {
+        const withDate = appendDateToLastUserMessage(base())
+        const dates = withDate
+          .flatMap((m) => m.parts)
+          .filter((p: any) => p.type === "text" && p.text?.includes(today))
+        expect(dates.length).toBe(1)
+      }
+    } finally {
+      setSystemTime()
+    }
+  })
+
+  test("date still reaches the model even when the user's real text was ignored", async () => {
+    // Edge raised in review: a user turn whose only real part is `ignored` would
+    // previously render empty; now it carries the date. The date must survive.
+    setSystemTime(new Date("2026-06-22T12:00:00.000Z"))
+    try {
+      const today = new Date().toDateString()
+      const input: MessageV2.WithParts[] = [
+        {
+          info: userInfo("m1"),
+          parts: [{ ...basePart("m1", "p1"), type: "text", text: "noise", ignored: true }] as MessageV2.Part[],
+        },
+      ]
+      const out = await MessageV2.toModelMessages(appendDateToLastUserMessage(input), model)
+      expect(JSON.stringify(out)).toContain(today)
+    } finally {
+      setSystemTime()
+    }
+  })
+
+  test("no user message present → append is a no-op and nothing throws", () => {
+    const input: MessageV2.WithParts[] = []
+    expect(() => appendDateToLastUserMessage(input)).not.toThrow()
+    expect(appendDateToLastUserMessage(input)).toEqual([])
+  })
+})
+
+// ---------------------------------------------------------------------------
+// #959 — Windows installer Pester harness regression guard (static)
+// ---------------------------------------------------------------------------
+describe("v0.8.10 #959: Windows installer Pester harness stays deterministic", () => {
+  const psPath = path.resolve(import.meta.dir, "../../../../test/windows/install.Tests.ps1")
+
+  test("env injection happens inside the child session, not via host inheritance", () => {
+    expect(fs.existsSync(psPath)).toBe(true)
+    const src = fs.readFileSync(psPath, "utf8")
+    // The fix sets the requested env vars in the child's own session (-Command
+    // preamble with `$env:` / Remove-Item) rather than mutating the host's
+    // Process-scope env and relying on `pwsh -File` inheritance — which the
+    // updated windows-latest runner re-initialized for loader-managed vars.
+    expect(src).toContain("-Command")
+    expect(src).toMatch(/\$env:/)
+    expect(src).toMatch(/Remove-Item -Path Env:/)
+    // The old, broken inheritance pattern must not come back.
+    expect(src).not.toMatch(/SetEnvironmentVariable/)
+  })
+})
