From e452857e57abf124ce8bc6415dd025417a9640ee Mon Sep 17 00:00:00 2001
From: Henry Mercer <henrymercer@github.com>
Date: Wed, 8 Apr 2026 16:33:19 +0100
Subject: [PATCH] Throw error early rather than warning

---
 lib/init-action.js | 10 +++++-----
 src/init-action.ts | 18 +++++++++---------
 2 files changed, 14 insertions(+), 14 deletions(-)

diff --git a/lib/init-action.js b/lib/init-action.js
index ce0331f73..e9afbeece 100644
--- a/lib/init-action.js
+++ b/lib/init-action.js
@@ -110299,6 +110299,11 @@ async function run(startedAt) {
       enableFileCoverageInformation: fileCoverageResult.enabled,
       logger
     });
+    if (config.languages.includes("swift" /* swift */) && process.platform === "linux") {
+      throw new ConfigurationError(
+        `Swift analysis on Ubuntu runner images is no longer supported. Please migrate to a macOS runner.`
+      );
+    }
     if (repositoryPropertiesResult.isFailure()) {
       addNoLanguageDiagnostic(
         config,
@@ -110383,11 +110388,6 @@ async function run(startedAt) {
         "Passing the GOFLAGS env parameter to the init action is deprecated. Please move this to the analyze action."
       );
     }
-    if (config.languages.includes("swift" /* swift */) && process.platform === "linux") {
-      logger.warning(
-        `Swift analysis on Ubuntu runner images is no longer supported. Please migrate to a macOS runner if this affects you.`
-      );
-    }
     if (config.languages.includes("go" /* go */) && process.platform === "linux") {
       try {
         const goBinaryPath = await io6.which("go", true);
diff --git a/src/init-action.ts b/src/init-action.ts
index 70d5d79ce..fd24fa6f8 100644
--- a/src/init-action.ts
+++ b/src/init-action.ts
@@ -389,6 +389,15 @@ async function run(startedAt: Date) {
       logger,
     });
 
+    if (
+      config.languages.includes(KnownLanguage.swift) &&
+      process.platform === "linux"
+    ) {
+      throw new ConfigurationError(
+        `Swift analysis on Ubuntu runner images is no longer supported. Please migrate to a macOS runner.`,
+      );
+    }
+
     if (repositoryPropertiesResult.isFailure()) {
       addNoLanguageDiagnostic(
         config,
@@ -499,15 +508,6 @@ async function run(startedAt: Date) {
       );
     }
 
-    if (
-      config.languages.includes(KnownLanguage.swift) &&
-      process.platform === "linux"
-    ) {
-      logger.warning(
-        `Swift analysis on Ubuntu runner images is no longer supported. Please migrate to a macOS runner if this affects you.`,
-      );
-    }
-
     if (
       config.languages.includes(KnownLanguage.go) &&
       process.platform === "linux"