From c0e8887d5a9cec04772d252b454d925dbdc4184f Mon Sep 17 00:00:00 2001
From: "Michael B. Gale" <mbg@github.com>
Date: Thu, 16 Oct 2025 20:03:26 +0100
Subject: [PATCH] Throw a `ConfigurationError` if `setup-codeql` has run before
 `init`

---
 lib/init-action.js         | 5 +++++
 lib/setup-codeql-action.js | 1 +
 src/environment.ts         | 3 +++
 src/init-action.ts         | 9 +++++++++
 src/setup-codeql-action.ts | 2 ++
 5 files changed, 20 insertions(+)

diff --git a/lib/init-action.js b/lib/init-action.js
index a113b2728..a07463f14 100644
--- a/lib/init-action.js
+++ b/lib/init-action.js
@@ -90784,6 +90784,11 @@ async function run() {
     if (statusReportBase !== void 0) {
       await sendStatusReport(statusReportBase);
     }
+    if (process.env["CODEQL_ACTION_SETUP_CODEQL_HAS_RUN" /* SETUP_CODEQL_ACTION_HAS_RUN */] === "true") {
+      throw new ConfigurationError(
+        `The 'init' action should not be run in the same workflow as 'setup-codeql'.`
+      );
+    }
     const codeQLDefaultVersionInfo = await features.getDefaultCliVersion(
       gitHubVersion.type
     );
diff --git a/lib/setup-codeql-action.js b/lib/setup-codeql-action.js
index a3e2b317b..a93c6f15a 100644
--- a/lib/setup-codeql-action.js
+++ b/lib/setup-codeql-action.js
@@ -87583,6 +87583,7 @@ async function run() {
     toolsSource = initCodeQLResult.toolsSource;
     core12.setOutput("codeql-path", codeql.getPath());
     core12.setOutput("codeql-version", (await codeql.getVersion()).version);
+    core12.exportVariable("CODEQL_ACTION_SETUP_CODEQL_HAS_RUN" /* SETUP_CODEQL_ACTION_HAS_RUN */, "true");
   } catch (unwrappedError) {
     const error2 = wrapError(unwrappedError);
     core12.setFailed(error2.message);
diff --git a/src/environment.ts b/src/environment.ts
index 7f554c762..698664122 100644
--- a/src/environment.ts
+++ b/src/environment.ts
@@ -47,6 +47,9 @@ export enum EnvVar {
   /** Whether the CodeQL Action has already warned the user about low disk space. */
   HAS_WARNED_ABOUT_DISK_SPACE = "CODEQL_ACTION_HAS_WARNED_ABOUT_DISK_SPACE",
 
+  /** Whether the `setup-codeql` action has been run. */
+  SETUP_CODEQL_ACTION_HAS_RUN = "CODEQL_ACTION_SETUP_CODEQL_HAS_RUN",
+
   /** Whether the init action has been run. */
   INIT_ACTION_HAS_RUN = "CODEQL_ACTION_INIT_HAS_RUN",
 
diff --git a/src/init-action.ts b/src/init-action.ts
index 13fa6c5b2..704985170 100644
--- a/src/init-action.ts
+++ b/src/init-action.ts
@@ -201,6 +201,7 @@ async function run() {
     ? await loadPropertiesFromApi(gitHubVersion, logger, repositoryNwo)
     : {};
 
+  // Create a unique identifier for this run.
   const jobRunUuid = uuidV4();
   logger.info(`Job run UUID is ${jobRunUuid}.`);
   core.exportVariable(EnvVar.JOB_RUN_UUID, jobRunUuid);
@@ -229,6 +230,14 @@ async function run() {
     if (statusReportBase !== undefined) {
       await sendStatusReport(statusReportBase);
     }
+
+    // Throw a `ConfigurationError` if the `setup-codeql` action has been run.
+    if (process.env[EnvVar.SETUP_CODEQL_ACTION_HAS_RUN] === "true") {
+      throw new ConfigurationError(
+        `The 'init' action should not be run in the same workflow as 'setup-codeql'.`,
+      );
+    }
+
     const codeQLDefaultVersionInfo = await features.getDefaultCliVersion(
       gitHubVersion.type,
     );
diff --git a/src/setup-codeql-action.ts b/src/setup-codeql-action.ts
index 2ab5515f1..af817b76a 100644
--- a/src/setup-codeql-action.ts
+++ b/src/setup-codeql-action.ts
@@ -152,6 +152,8 @@ async function run(): Promise<void> {
 
     core.setOutput("codeql-path", codeql.getPath());
     core.setOutput("codeql-version", (await codeql.getVersion()).version);
+
+    core.exportVariable(EnvVar.SETUP_CODEQL_ACTION_HAS_RUN, "true");
   } catch (unwrappedError) {
     const error = wrapError(unwrappedError);
     core.setFailed(error.message);