Resolve Python architecture during input loading

__tests__/cache/restore-cache.test.ts

@@ -1,11 +1,4 @@
-import {
-  afterEach,
-  beforeEach,
-  describe,
-  expect,
-  it,
-  jest,
-} from "@jest/globals";
+import { beforeEach, describe, expect, it, jest } from "@jest/globals";
 import { createSetupInputs } from "../helpers/setup-inputs";
 
 const mockRestoreCache = jest.fn();
@@ -14,7 +7,6 @@ const mockSetOutput = jest.fn();
 const mockGetArch = jest.fn(() => "x86_64");
 const mockGetOSNameVersion = jest.fn(() => "ubuntu-24.04");
 const mockGetPlatform = jest.fn(async () => "unknown-linux-gnu");
-const ORIGINAL_UV_PYTHON_ARCH = process.env.UV_PYTHON_ARCH;
 
 jest.unstable_mockModule("@actions/cache", () => ({
   restoreCache: mockRestoreCache,
@@ -49,21 +41,12 @@ function cacheKeyOutput(): string {
 }
 
 beforeEach(() => {
-  delete process.env.UV_PYTHON_ARCH;
   jest.clearAllMocks();
   mockGetArch.mockReturnValue("x86_64");
   mockGetOSNameVersion.mockReturnValue("ubuntu-24.04");
   mockGetPlatform.mockResolvedValue("unknown-linux-gnu");
 });
 
-afterEach(() => {
-  if (ORIGINAL_UV_PYTHON_ARCH === undefined) {
-    delete process.env.UV_PYTHON_ARCH;
-  } else {
-    process.env.UV_PYTHON_ARCH = ORIGINAL_UV_PYTHON_ARCH;
-  }
-});
-
 describe("restoreCache", () => {
   it("encodes Python version ranges before adding them to the cache key", async () => {
     await restoreCache(createSetupInputs(), ">3.10.11,<3.11");
@@ -95,10 +78,10 @@ describe("restoreCache", () => {
     );
   });
 
-  it("includes an inherited Python architecture in the cache key", async () => {
-    process.env.UV_PYTHON_ARCH = "aarch64";
+  it("includes the resolved Python architecture in the cache key", async () => {
+    const inputs = createSetupInputs({ pythonArch: "aarch64" });
 
-    await restoreCache(createSetupInputs(), "3.14");
+    await restoreCache(inputs, "3.14");
 
     expect(cacheKeyOutput()).toContain("-3.14-python-aarch64-");
   });

__tests__/helpers/setup-inputs.ts

@@ -16,6 +16,7 @@ export function createSetupInputs(
     checksum: "",
     downloadFromAstralMirror: false,
     enableCache: true,
+    exportPythonArch: false,
     githubToken: "",
     ignoreEmptyWorkdir: false,
     ignoreNothingToCache: false,

__tests__/utils/inputs.test.ts

@@ -38,9 +38,7 @@ jest.unstable_mockModule("@actions/core", () => ({
   warning: mockWarning,
 }));
 
-const { CacheLocalSource, loadInputs, resolvePythonArch } = await import(
-  "../../src/utils/inputs"
-);
+const { CacheLocalSource, loadInputs } = await import("../../src/utils/inputs");
 
 function createTempProject(files: Record<string, string> = {}): string {
   const dir = fs.mkdtempSync(path.join(os.tmpdir(), "setup-uv-inputs-test-"));
@@ -108,6 +106,7 @@ describe("loadInputs", () => {
     });
     expect(inputs.pythonDir).toBe("/runner-temp/uv-python-dir");
     expect(inputs.pythonArch).toBe("");
+    expect(inputs.exportPythonArch).toBe(false);
     expect(inputs.venvPath).toBe("/workspace/.venv");
     expect(inputs.manifestFile).toBeUndefined();
     expect(inputs.resolutionStrategy).toBe("highest");
@@ -166,7 +165,7 @@ describe("loadInputs", () => {
 
     const inputs = loadInputs();
     expect(inputs.pythonArch).toBe("x86_64");
-    expect(resolvePythonArch(inputs.pythonArch)).toBe("x86_64");
+    expect(inputs.exportPythonArch).toBe(true);
   });
 
   it.each(["aarch64", "x86_64_v3", ""])(
@@ -176,8 +175,8 @@ describe("loadInputs", () => {
       process.env.UV_PYTHON_ARCH = pythonArch;
 
       const inputs = loadInputs();
-      expect(inputs.pythonArch).toBe("");
-      expect(resolvePythonArch(inputs.pythonArch)).toBe(pythonArch);
+      expect(inputs.pythonArch).toBe(pythonArch);
+      expect(inputs.exportPythonArch).toBe(false);
     },
   );
 

__tests__/utils/python-arch.test.ts

@@ -57,16 +57,16 @@ afterEach(() => {
 
 describe("setupPythonArch", () => {
   it("leaves Python selection alone without an architecture", async () => {
-    await setupPythonArch("/tools/uv", "");
+    await setupPythonArch("/tools/uv", "", false);
 
     expect(mockExecFile).not.toHaveBeenCalled();
     expect(mockExportVariable).not.toHaveBeenCalled();
   });
 
-  it("validates an inherited architecture without exporting it", async () => {
+  it("validates a resolved environment architecture without exporting it", async () => {
     process.env.UV_PYTHON_ARCH = "aarch64";
 
-    await setupPythonArch("/tools/uv", "");
+    await setupPythonArch("/tools/uv", "aarch64", false);
 
     expect(mockExecFile).toHaveBeenNthCalledWith(
       2,
@@ -83,7 +83,7 @@ describe("setupPythonArch", () => {
   it.each(["/runner temp/uv", "C:\\runner temp\\uv.exe"])(
     "validates and exports the architecture using the installed uv: %s",
     async (uvPath) => {
-      await setupPythonArch(uvPath, "x86_64");
+      await setupPythonArch(uvPath, "x86_64", true);
 
       expect(mockExecFile).toHaveBeenNthCalledWith(
         1,
@@ -112,7 +112,7 @@ describe("setupPythonArch", () => {
   it("rejects uv versions that ignore UV_PYTHON_ARCH", async () => {
     mockExecFile.mockReset().mockResolvedValue(success);
 
-    await expect(setupPythonArch("/tools/uv", "x86_64")).rejects.toThrow(
+    await expect(setupPythonArch("/tools/uv", "x86_64", true)).rejects.toThrow(
       "The installed version of uv does not support UV_PYTHON_ARCH",
     );
     expect(mockExecFile).toHaveBeenCalledTimes(1);
@@ -127,7 +127,7 @@ describe("setupPythonArch", () => {
       }),
     );
 
-    await expect(setupPythonArch("/tools/uv", "x86_64")).rejects.toThrow(
+    await expect(setupPythonArch("/tools/uv", "x86_64", true)).rejects.toThrow(
       "Failed to check uv's support for UV_PYTHON_ARCH: error: unrelated configuration error",
     );
     expect(mockExportVariable).not.toHaveBeenCalled();
@@ -144,7 +144,7 @@ describe("setupPythonArch", () => {
         }),
       );
 
-    await expect(setupPythonArch("/tools/uv", "invalid")).rejects.toThrow(
+    await expect(setupPythonArch("/tools/uv", "invalid", true)).rejects.toThrow(
       "Failed to set Python architecture to invalid: error: Unknown architecture: invalid",
     );
     expect(mockExportVariable).not.toHaveBeenCalled();

dist/save-cache/index.cjs

@@ -63714,6 +63714,15 @@ function info2(msg) {
 }
 var warning2 = warning;
 
+// src/cache/restore-cache.ts
+var STATE_CACHE_KEY = "cache-key";
+var STATE_CACHE_MATCHED_KEY = "cache-matched-key";
+var STATE_PYTHON_CACHE_MATCHED_KEY = "python-cache-matched-key";
+
+// src/utils/constants.ts
+var STATE_UV_PATH = "uv-path";
+var STATE_UV_VERSION = "uv-version";
+
 // src/utils/inputs.ts
 var import_node_fs4 = __toESM(require("node:fs"), 1);
 var import_node_path = __toESM(require("node:path"), 1);
@@ -64438,7 +64447,9 @@ function loadInputs() {
   const version3 = getInput("version");
   const versionFile = getVersionFile(workingDirectory);
   const pythonVersion = getPythonVersion(versionFile);
-  const pythonArch = getInput("python-arch");
+  const pythonArchInput = getInput("python-arch");
+  const pythonArch = pythonArchInput || process.env.UV_PYTHON_ARCH || "";
+  const exportPythonArch = pythonArchInput !== "";
   const activateEnvironment = getBooleanInput("activate-environment");
   const noProject = getBooleanInput("no-project");
   const venvPath = getVenvPath(workingDirectory, activateEnvironment);
@@ -64476,6 +64487,7 @@ function loadInputs() {
     checksum,
     downloadFromAstralMirror,
     enableCache,
+    exportPythonArch,
     githubToken,
     ignoreEmptyWorkdir,
     ignoreNothingToCache,
@@ -64731,15 +64743,6 @@ function getResolutionStrategy() {
   );
 }
 
-// src/cache/restore-cache.ts
-var STATE_CACHE_KEY = "cache-key";
-var STATE_CACHE_MATCHED_KEY = "cache-matched-key";
-var STATE_PYTHON_CACHE_MATCHED_KEY = "python-cache-matched-key";
-
-// src/utils/constants.ts
-var STATE_UV_PATH = "uv-path";
-var STATE_UV_VERSION = "uv-version";
-
 // src/save-cache.ts
 function formatUnexpectedFailure(error2) {
   if (error2 instanceof Error) {

src/cache/restore-cache.ts

@@ -1,7 +1,7 @@
 import * as cache from "@actions/cache";
 import * as core from "@actions/core";
 import { hashFiles } from "../hash/hash-files";
-import { resolvePythonArch, type SetupInputs } from "../utils/inputs";
+import type { SetupInputs } from "../utils/inputs";
 import * as log from "../utils/logging";
 import { getArch, getOSNameVersion, getPlatform } from "../utils/platforms";
 
@@ -98,9 +98,8 @@ async function computeKeys(
     ? `-${encodeURIComponent(inputs.cacheSuffix)}`
     : "";
   const version = encodeURIComponent(pythonVersion ?? "unknown");
-  const pythonArch = resolvePythonArch(inputs.pythonArch);
-  const pythonArchKey = pythonArch
-    ? `-python-${encodeURIComponent(pythonArch)}`
+  const pythonArchKey = inputs.pythonArch
+    ? `-python-${encodeURIComponent(inputs.pythonArch)}`
     : "";
   const platform = await getPlatform();
   const osNameVersion = getOSNameVersion();

src/setup-uv.ts

@@ -91,7 +91,7 @@ async function run(): Promise<void> {
       setupResult.uvDir,
       process.platform === "win32" ? "uv.exe" : "uv",
     );
-    await setupPythonArch(uvPath, inputs.pythonArch);
+    await setupPythonArch(uvPath, inputs.pythonArch, inputs.exportPythonArch);
 
     addToolBinToPath(inputs);
     addUvToPathAndOutput(setupResult.uvDir);

src/utils/inputs.ts

@@ -25,6 +25,7 @@ export interface SetupInputs {
   versionFile: string;
   pythonVersion: string;
   pythonArch: string;
+  exportPythonArch: boolean;
   activateEnvironment: boolean;
   noProject: boolean;
   venvPath: string;
@@ -55,7 +56,9 @@ export function loadInputs(): SetupInputs {
   const version = core.getInput("version");
   const versionFile = getVersionFile(workingDirectory);
   const pythonVersion = getPythonVersion(versionFile);
-  const pythonArch = core.getInput("python-arch");
+  const pythonArchInput = core.getInput("python-arch");
+  const pythonArch = pythonArchInput || process.env.UV_PYTHON_ARCH || "";
+  const exportPythonArch = pythonArchInput !== "";
   const activateEnvironment = core.getBooleanInput("activate-environment");
   const noProject = core.getBooleanInput("no-project");
   const venvPath = getVenvPath(workingDirectory, activateEnvironment);
@@ -96,6 +99,7 @@ export function loadInputs(): SetupInputs {
     checksum,
     downloadFromAstralMirror,
     enableCache,
+    exportPythonArch,
     githubToken,
     ignoreEmptyWorkdir,
     ignoreNothingToCache,
@@ -149,10 +153,6 @@ function getPythonVersion(versionFile: string): string {
   }
 }
 
-export function resolvePythonArch(pythonArch: string): string {
-  return pythonArch || process.env.UV_PYTHON_ARCH || "";
-}
-
 function getVenvPath(
   workingDirectory: string,
   activateEnvironment: boolean,

src/utils/python-arch.ts

@@ -1,7 +1,6 @@
 import { execFile } from "node:child_process";
 import { promisify } from "node:util";
 import * as core from "@actions/core";
-import { resolvePythonArch } from "./inputs";
 import * as log from "./logging";
 
 const execFileAsync = promisify(execFile);
@@ -9,9 +8,9 @@ const PROBE_ARCH = "setup-uv-probe";
 
 export async function setupPythonArch(
   uvPath: string,
-  pythonArchInput: string,
+  pythonArch: string,
+  exportPythonArch: boolean,
 ): Promise<void> {
-  const pythonArch = resolvePythonArch(pythonArchInput);
   if (pythonArch === "") {
     return;
   }
@@ -41,7 +40,7 @@ export async function setupPythonArch(
     );
   }
 
-  if (pythonArchInput !== "") {
+  if (exportPythonArch) {
     core.exportVariable("UV_PYTHON_ARCH", pythonArch);
     log.info(`Set UV_PYTHON_ARCH to ${pythonArch}`);
   }