diff --git a/lib/entry-points.js b/lib/entry-points.js
index e59d461fa..c52cc88f5 100644
--- a/lib/entry-points.js
+++ b/lib/entry-points.js
@@ -175748,14 +175748,14 @@ function logPerLanguageBundleFallback({ logger: logger2 }, language, location) {
 
 // src/setup/repository.ts
 var CODEQL_DEFAULT_ACTION_REPOSITORY = "github/codeql-action";
-function getCodeQLActionRepository(logger2) {
-  if (isRunningLocalAction()) {
-    logger2.info(
+function getCodeQLActionRepository(action) {
+  if (isRunningLocalAction(action.env)) {
+    action.logger.info(
       "The CodeQL Action is checked out locally. Using the default CodeQL Action repository."
     );
     return CODEQL_DEFAULT_ACTION_REPOSITORY;
   }
-  return getRequiredEnvParam("GITHUB_ACTION_REPOSITORY");
+  return action.env.getRequired("GITHUB_ACTION_REPOSITORY" /* GITHUB_ACTION_REPOSITORY */);
 }
 
 // src/tar.ts
@@ -176155,7 +176155,10 @@ var CODEQL_BUNDLE_VERSION_ALIAS = ["linked", "latest"];
 var CODEQL_NIGHTLY_TOOLS_INPUTS = ["nightly", "nightly-latest"];
 var CODEQL_TOOLCACHE_INPUT = "toolcache";
 async function getCodeQLBundleDownloadURL(tagName, apiDetails, codeQLBundleName, logger2) {
-  const codeQLActionRepository = getCodeQLActionRepository(logger2);
+  const codeQLActionRepository = getCodeQLActionRepository({
+    logger: logger2,
+    env: getEnv()
+  });
   const potentialDownloadSources = [
     // This GitHub instance, and this Action.
     [apiDetails.url, codeQLActionRepository],
diff --git a/src/actions-util.ts b/src/actions-util.ts
index 62ab42440..6db7146d1 100644
--- a/src/actions-util.ts
+++ b/src/actions-util.ts
@@ -101,7 +101,7 @@ export function getWorkflowEventName(env: Env = getEnv()) {
  * Returns whether the current workflow is executing a local copy of the Action, e.g. we're running
  * a workflow on the codeql-action repo itself.
  */
-export function isRunningLocalAction(env: Env = getEnv()): boolean {
+export function isRunningLocalAction(env: ReadOnlyEnv = getEnv()): boolean {
   const relativeScriptPath = getRelativeScriptPath(env);
   return (
     relativeScriptPath.startsWith("..") || path.isAbsolute(relativeScriptPath)
@@ -113,7 +113,7 @@ export function isRunningLocalAction(env: Env = getEnv()): boolean {
  *
  * This can be used to get the Action's name or tell if we're running a local Action.
  */
-function getRelativeScriptPath(env: Env): string {
+function getRelativeScriptPath(env: ReadOnlyEnv): string {
   const runnerTemp = env.getRequired(ActionsEnvVars.RUNNER_TEMP);
   const actionsDirectory = path.join(path.dirname(runnerTemp), "_actions");
   return path.relative(actionsDirectory, __filename);
diff --git a/src/setup-codeql.ts b/src/setup-codeql.ts
index 760f6e4aa..54117c95d 100644
--- a/src/setup-codeql.ts
+++ b/src/setup-codeql.ts
@@ -82,7 +82,10 @@ async function getCodeQLBundleDownloadURL(
   codeQLBundleName: string,
   logger: Logger,
 ): Promise<string> {
-  const codeQLActionRepository = getCodeQLActionRepository(logger);
+  const codeQLActionRepository = getCodeQLActionRepository({
+    logger,
+    env: getEnv(),
+  });
   const potentialDownloadSources = [
     // This GitHub instance, and this Action.
     [apiDetails.url, codeQLActionRepository],
diff --git a/src/setup/repository.test.ts b/src/setup/repository.test.ts
index c3dccbf9c..56eb74786 100644
--- a/src/setup/repository.test.ts
+++ b/src/setup/repository.test.ts
@@ -4,28 +4,31 @@ import test from "ava";
 import * as sinon from "sinon";
 
 import * as actionsUtil from "../actions-util";
-import { getRunnerLogger } from "../logging";
-import { setupTests } from "../testing-utils";
+import { ActionsEnvVars } from "../environment";
+import { callee, setupTests } from "../testing-utils";
 import { initializeEnvironment } from "../util";
 
 import { getCodeQLActionRepository } from "./repository";
 
 setupTests(test);
 
-test.serial("getCodeQLActionRepository", (t) => {
-  const logger = getRunnerLogger(true);
-
+test.serial("getCodeQLActionRepository", async (t) => {
   initializeEnvironment("1.2.3");
 
+  const target = callee(getCodeQLActionRepository)
+    .withArgs()
+    .withEnv((env) => {
+      env.set(ActionsEnvVars.RUNNER_TEMP, path.dirname(__dirname));
+    });
+
   // isRunningLocalAction() === true
-  delete process.env["GITHUB_ACTION_REPOSITORY"];
-  process.env["RUNNER_TEMP"] = path.dirname(__dirname);
-  const repoLocalRunner = getCodeQLActionRepository(logger);
-  t.deepEqual(repoLocalRunner, "github/codeql-action");
+  await target.passes(t.deepEqual, "github/codeql-action");
 
   // isRunningLocalAction() === false
   sinon.stub(actionsUtil, "isRunningLocalAction").returns(false);
-  process.env["GITHUB_ACTION_REPOSITORY"] = "xxx/yyy";
-  const repoEnv = getCodeQLActionRepository(logger);
-  t.deepEqual(repoEnv, "xxx/yyy");
+  await target
+    .withEnv((env) => {
+      env.set(ActionsEnvVars.GITHUB_ACTION_REPOSITORY, "xxx/yyy");
+    })
+    .passes(t.deepEqual, "xxx/yyy");
 });
diff --git a/src/setup/repository.ts b/src/setup/repository.ts
index 908cc39ee..c58470630 100644
--- a/src/setup/repository.ts
+++ b/src/setup/repository.ts
@@ -1,19 +1,30 @@
+import { ActionState } from "../action-common";
 import { isRunningLocalAction } from "../actions-util";
-import { Logger } from "../logging";
-import * as util from "../util";
+import { ActionsEnvVars } from "../environment";
 
+/** The NWO of the standard CodeQL Action repository. */
 export const CODEQL_DEFAULT_ACTION_REPOSITORY = "github/codeql-action";
 
-export function getCodeQLActionRepository(logger: Logger): string {
-  if (isRunningLocalAction()) {
+/**
+ * Retrieves the NWO of the repository that the CodeQL Action is loaded from.
+ * Typically, this will be `github/codeql-action`, but it may be something else for
+ * forks of the Action or in environments other than GitHub.com.
+ *
+ * If this function detects that we are running the Action locally (e.g. in tests),
+ * then we default to `CODEQL_DEFAULT_ACTION_REPOSITORY`.
+ */
+export function getCodeQLActionRepository(
+  action: ActionState<["ReadOnlyEnv", "Logger"]>,
+): string {
+  if (isRunningLocalAction(action.env)) {
     // This handles the case where the Action does not come from an Action repository,
     // e.g. our integration tests which use the Action code from the current checkout.
     // In these cases, the GITHUB_ACTION_REPOSITORY environment variable is not set.
-    logger.info(
+    action.logger.info(
       "The CodeQL Action is checked out locally. Using the default CodeQL Action repository.",
     );
     return CODEQL_DEFAULT_ACTION_REPOSITORY;
   }
 
-  return util.getRequiredEnvParam("GITHUB_ACTION_REPOSITORY");
+  return action.env.getRequired(ActionsEnvVars.GITHUB_ACTION_REPOSITORY);
 }