From da4362111aa931b9189cf7ab092756c839b49fda Mon Sep 17 00:00:00 2001
From: paulvas <paulvas@gmail.com>
Date: Mon, 12 Jan 2026 12:58:59 -0500
Subject: [PATCH] Fix: Enforce compiler warnings in oauth2-core

To prevent future compiler warnings from being introduced, this change
applies the `compile-warnings-error` plugin to the
`spring-security-oauth2-core` module.

This ensures that any new warnings will fail the build, maintaining
code quality and preventing warning accumulation.

Fixes: gh-18434
Signed-off-by: Pavel Vassiliev <paulvas@gmail.com>
Signed-off-by: paulvas <paulvas@gmail.com>
---
 buildSrc/build.gradle                             |  4 ++++
 .../src/main/groovy/compile-warnings-error.groovy | 15 +++++++++++++++
 .../spring-security-oauth2-core.gradle            |  4 ++++
 3 files changed, 23 insertions(+)
 create mode 100644 buildSrc/src/main/groovy/compile-warnings-error.groovy

diff --git a/buildSrc/build.gradle b/buildSrc/build.gradle
index da60b4197b..aff57d3a1e 100644
--- a/buildSrc/build.gradle
+++ b/buildSrc/build.gradle
@@ -52,6 +52,10 @@ gradlePlugin {
 			id = "org.springframework.security.check-expected-branch-version"
 			implementationClass = "org.springframework.security.CheckExpectedBranchVersionPlugin"
 		}
+		compileWarningsError {
+			id = "compile-warnings-error"
+			implementationClass = "CompileWarningsErrorPlugin"
+ 		}
 	}
 }
 
diff --git a/buildSrc/src/main/groovy/compile-warnings-error.groovy b/buildSrc/src/main/groovy/compile-warnings-error.groovy
new file mode 100644
index 0000000000..f2d073de3c
--- /dev/null
+++ b/buildSrc/src/main/groovy/compile-warnings-error.groovy
@@ -0,0 +1,15 @@
+import org.gradle.api.Plugin
+import org.gradle.api.Project
+import org.gradle.api.tasks.compile.JavaCompile
+import org.jetbrains.kotlin.gradle.tasks.KotlinCompile
+
+class CompileWarningsErrorPlugin implements Plugin<Project> {
+    void apply(Project project) {
+        project.tasks.withType(JavaCompile) {
+            options.compilerArgs += "-Werror"
+        }
+        project.tasks.withType(KotlinCompile) {
+            kotlinOptions.allWarningsAsErrors = true
+        }
+    }
+}
\ No newline at end of file
diff --git a/oauth2/oauth2-core/spring-security-oauth2-core.gradle b/oauth2/oauth2-core/spring-security-oauth2-core.gradle
index c163adfcca..a3c3a2f4e9 100644
--- a/oauth2/oauth2-core/spring-security-oauth2-core.gradle
+++ b/oauth2/oauth2-core/spring-security-oauth2-core.gradle
@@ -1,3 +1,7 @@
+plugins {
+	id 'compile-warnings-error'
+}
+
 apply plugin: 'io.spring.convention.spring-module'
 
 dependencies {