bootRun task fails to correctly signal startup errors / non-zero exit values to Gradle when devtools are active

[christianhujer]

Context: Spring Boot Gradle plugin.
Spring Boot version 3.4.4
Gradle version: 8.13

Use Case: Launching a Spring Boot application via the bootRun Gradle task.
Scenario: The Spring Boot application fails to launch, for example, because its port is already in use.

Expected behavior: The bootRun task fails the Gradle build.
Actual behavior: The Gradle build reports success.

The very same Spring Boot application, when launched from the command line, correctly signals a failed start by setting the process exit value to 1. This makes me believe that the issue is with the Gradle Plugin.

I will provide a sample project shortly and update this ticket once it is available.

[christianhujer]

Here's the showcase: https://github.com/christianhujer/springboot-44848

While creating the showcase, I figured that the unexpected behavior only occurs when org.springframework.boot:spring-boot-devtools is in the dependencies. I've updated the issue title accordingly.

From here, I see multiple options:

• The defect is in the Gradle task but somehow only occurs when devtools is active.
• The defect is in devtools.
• This is not a defect but intended behavior when devtools is active. I tried to find this in https://docs.spring.io/spring-boot/reference/using/devtools.html but couldn't.

[wilkinsona]

Thanks, @christianhujer. With this only happening when devtools is involved, I am pretty sure it’s a duplicate of #28541.