diff --git a/__tests__/utils.test.ts b/__tests__/utils.test.ts
new file mode 100644
index 0000000..4b40f33
--- /dev/null
+++ b/__tests__/utils.test.ts
@@ -0,0 +1,52 @@
+import {isSelfHosted} from '../src/utils';
+
+describe('utils', () => {
+  describe('isSelfHosted', () => {
+    let AGENT_ISSELFHOSTED: string | undefined;
+    let RUNNER_ENVIRONMENT: string | undefined;
+
+    beforeEach(() => {
+      AGENT_ISSELFHOSTED = process.env['AGENT_ISSELFHOSTED'];
+      delete process.env['AGENT_ISSELFHOSTED'];
+      RUNNER_ENVIRONMENT = process.env['RUNNER_ENVIRONMENT'];
+      delete process.env['RUNNER_ENVIRONMENT'];
+    });
+
+    afterEach(() => {
+      if (AGENT_ISSELFHOSTED === undefined) {
+        delete process.env['AGENT_ISSELFHOSTED'];
+      } else {
+        process.env['AGENT_ISSELFHOSTED'] = AGENT_ISSELFHOSTED;
+      }
+      if (RUNNER_ENVIRONMENT === undefined) {
+        delete process.env['RUNNER_ENVIRONMENT'];
+      } else {
+        process.env['RUNNER_ENVIRONMENT'] = RUNNER_ENVIRONMENT;
+      }
+    });
+
+    it('isSelfHosted should be true if no environment variables set', () => {
+      expect(isSelfHosted()).toBeTruthy();
+    });
+
+    it('isSelfHosted should be true if environment variable is not set to denote GitHub hosted', () => {
+      process.env['RUNNER_ENVIRONMENT'] = 'some';
+      expect(isSelfHosted()).toBeTruthy();
+    });
+
+    it('isSelfHosted should be true if environment variable set to denote Azure Pipelines self hosted', () => {
+      process.env['AGENT_ISSELFHOSTED'] = '1';
+      expect(isSelfHosted()).toBeTruthy();
+    });
+
+    it('isSelfHosted should be false if environment variable set to denote GitHub hosted', () => {
+      process.env['RUNNER_ENVIRONMENT'] = 'github-hosted';
+      expect(isSelfHosted()).toBeFalsy();
+    });
+
+    it('isSelfHosted should be false if environment variable is not set to denote Azure Pipelines self hosted', () => {
+      process.env['AGENT_ISSELFHOSTED'] = 'some';
+      expect(isSelfHosted()).toBeFalsy();
+    });
+  });
+});
diff --git a/dist/setup/index.js b/dist/setup/index.js
index 10c204a..ad9ec49 100644
--- a/dist/setup/index.js
+++ b/dist/setup/index.js
@@ -93270,8 +93270,7 @@ function cacheWindowsDir(extPath, tool, version, arch) {
         if (os_1.default.platform() !== 'win32')
             return false;
         // make sure the action runs in the hosted environment
-        if (process.env['RUNNER_ENVIRONMENT'] !== 'github-hosted' &&
-            process.env['AGENT_ISSELFHOSTED'] === '1')
+        if ((0, utils_1.isSelfHosted)())
             return false;
         const defaultToolCacheRoot = process.env['RUNNER_TOOL_CACHE'];
         if (!defaultToolCacheRoot)
@@ -93778,12 +93777,21 @@ exports.getArch = getArch;
 "use strict";
 
 Object.defineProperty(exports, "__esModule", ({ value: true }));
-exports.StableReleaseAlias = void 0;
+exports.isSelfHosted = exports.StableReleaseAlias = void 0;
 var StableReleaseAlias;
 (function (StableReleaseAlias) {
     StableReleaseAlias["Stable"] = "stable";
     StableReleaseAlias["OldStable"] = "oldstable";
 })(StableReleaseAlias || (exports.StableReleaseAlias = StableReleaseAlias = {}));
+const isSelfHosted = () => process.env['RUNNER_ENVIRONMENT'] !== 'github-hosted' &&
+    (process.env['AGENT_ISSELFHOSTED'] === '1' ||
+        process.env['AGENT_ISSELFHOSTED'] === undefined);
+exports.isSelfHosted = isSelfHosted;
+/* the above is simplified from:
+    process.env['RUNNER_ENVIRONMENT'] !== 'github-hosted' && process.env['AGENT_ISSELFHOSTED'] === '1'
+    ||
+    process.env['RUNNER_ENVIRONMENT'] !== 'github-hosted' && process.env['AGENT_ISSELFHOSTED'] === undefined
+*/
 
 
 /***/ }),
diff --git a/src/installer.ts b/src/installer.ts
index cc0f2dc..fa1c853 100644
--- a/src/installer.ts
+++ b/src/installer.ts
@@ -6,7 +6,7 @@ import * as httpm from '@actions/http-client';
 import * as sys from './system';
 import fs from 'fs';
 import os from 'os';
-import {StableReleaseAlias} from './utils';
+import {StableReleaseAlias, isSelfHosted} from './utils';
 
 const MANIFEST_REPO_OWNER = 'actions';
 const MANIFEST_REPO_NAME = 'go-versions';
@@ -180,11 +180,7 @@ async function cacheWindowsDir(
   if (os.platform() !== 'win32') return false;
 
   // make sure the action runs in the hosted environment
-  if (
-    process.env['RUNNER_ENVIRONMENT'] !== 'github-hosted' &&
-    process.env['AGENT_ISSELFHOSTED'] === '1'
-  )
-    return false;
+  if (isSelfHosted()) return false;
 
   const defaultToolCacheRoot = process.env['RUNNER_TOOL_CACHE'];
   if (!defaultToolCacheRoot) return false;
diff --git a/src/utils.ts b/src/utils.ts
index 79d03bc..19f5296 100644
--- a/src/utils.ts
+++ b/src/utils.ts
@@ -2,3 +2,13 @@ export enum StableReleaseAlias {
   Stable = 'stable',
   OldStable = 'oldstable'
 }
+
+export const isSelfHosted = (): boolean =>
+  process.env['RUNNER_ENVIRONMENT'] !== 'github-hosted' &&
+  (process.env['AGENT_ISSELFHOSTED'] === '1' ||
+    process.env['AGENT_ISSELFHOSTED'] === undefined);
+/* the above is simplified from:
+    process.env['RUNNER_ENVIRONMENT'] !== 'github-hosted' && process.env['AGENT_ISSELFHOSTED'] === '1'
+    ||
+    process.env['RUNNER_ENVIRONMENT'] !== 'github-hosted' && process.env['AGENT_ISSELFHOSTED'] === undefined
+*/