^M characters in MANIFEST.MF file generated using gradle

Question

Cross posting from http://forums.gradle.org/gradle/topics/_m_in_manifest_mf_file_generated_through_gradle

I am seeing a problem with the jar manifest file in my gradle project. I am generating a manifest file for the jar in my build as -

project(':myproject') {
        jar {
            manifest {
                attributes 'Implementation-Title': 'My Project',
                    'Implementation-Version': project.version,
                    'Built-By': System.getProperty('user.name'),
                    'Built-Date': new Date(),
                    'Built-JDK': System.getProperty('java.version'),
                    'Created-By': 'Gradle',
                    'Git-Commit': getSCMRevision(),
                    'Git-Branch': getSCMBranch()
            }
        }
}

where getSCMRevision() and getSCMBranch() are static methods that are exposed through a custom plugin.

After the build executes, the MANIFEST.MF file has all the right information, however, it seems to add one or more '^M' characters at the end of every line. Due to this, when I try to execute a java command using a main class that is contained in this project's jar, java errors as - Error: Could not find or load main class. This is presumably because the jar has a corrupt MANIFEST.MF. As soon as I unpack the jar, remove the '^M' characters and rebuild the jar using 'jar cf', the java commands work.

I can see this error when I build both on OSX (Mavericks) as well as Centos 6.3. I am using gradle 1.11

If this has to do with file encoding, is there a recommended way of setting the encoding? Any other possible solutions to this?

Thanks in advance,

Bhooshan

---

UPDATE: This issue seems to occur because the methods getSCMRevision() and getSCMBranch() are defined in a custom plugin. If I remove these methods, the MANIFEST.MF file does not contain ^M characters. If I completely move the manifest definition to the custom plugin, I see the issue. If I define everything in my project's build.gradle instead, I do not see the ^M characters. They seem to show up only if I invoke any functionality from the custom plugin in the manifest closure.

Any thoughts?