test: cover managed binary cleanup boundaries

Author: navedmerchant

src/services/code-index/semble/__tests__/semble-downloader.spec.ts

@@ -925,7 +925,7 @@ describe("semble-downloader", () => {
 				// excluded by the currentArchivePath guard). It is unlinked only by
 				// the pre-download partial-archive cleanup and the post-install
 				// archive cleanup steps. unrelated.txt is never touched.
-				expect(fs.unlink).not.toHaveBeenCalledWith(path.join("/storage", "unrelated.txt"))
+				expect(fs.rm).not.toHaveBeenCalledWith(path.join("/storage", "unrelated.txt"), expect.anything())
 				// Sanity: the current archive path is never passed to the stale sweep.
 				// It is unlinked exactly twice (pre-download cleanup + post-install
 				// archive cleanup), never via cleanupStaleArchives.

src/services/managed-binary/__tests__/archive.spec.ts

@@ -157,14 +157,25 @@ describe("managed binary archive utilities", () => {
 	it("builds a single-entry-validated PowerShell ZIP extraction", async () => {
 		const child = createChild()
 		mockSpawn.mockReturnValue(child as unknown as ReturnType<typeof spawn>)
-		const extraction = extractSingleFileZipArchive("C:\\archive.zip", "C:\\output", "binary.exe", "Tool")
-		child.emit("close", 0)
-		await extraction
-
-		const args = mockSpawn.mock.calls[0][1]
-		const script = args[3]
-		expect(script).toContain("$entries.Count -ne 1")
-		expect(script).not.toContain("C:\\archive.zip")
-		expect(args.slice(4)).toEqual(["C:\\archive.zip", path.join("C:\\output", "binary.exe"), "binary.exe", "Tool"])
+		const originalPlatform = Object.getOwnPropertyDescriptor(process, "platform")
+		Object.defineProperty(process, "platform", { value: "win32", configurable: true })
+		try {
+			const extraction = extractSingleFileZipArchive("C:\\archive.zip", "C:\\output", "binary.exe", "Tool")
+			child.emit("close", 0)
+			await extraction
+
+			const args = mockSpawn.mock.calls[0][1]
+			const script = args[3]
+			expect(script).toContain("$entries.Count -ne 1")
+			expect(script).not.toContain("C:\\archive.zip")
+			expect(args.slice(4)).toEqual([
+				"C:\\archive.zip",
+				path.join("C:\\output", "binary.exe"),
+				"binary.exe",
+				"Tool",
+			])
+		} finally {
+			if (originalPlatform) Object.defineProperty(process, "platform", originalPlatform)
+		}
 	})
 })

src/services/managed-binary/archive.ts

@@ -70,7 +70,10 @@ export async function extractSingleFileZipArchive(
 	expectedFile: string,
 	archiveName: string,
 ): Promise<void> {
-	// This deliberately uses PowerShell because it is only called for Windows release archives.
+	if (process.platform !== "win32") {
+		throw new Error("Single-file ZIP extraction is only supported on Windows")
+	}
+
 	const script = [
 		"$ErrorActionPreference = 'Stop'",
 		"$archivePath = $args[0]",