As a workaround, you can attach the sources from the gradle distribution if you have downloaded them:

import org.gradle.plugins.ide.eclipse.model.*

eclipse {
classpath {
file {
whenMerged {Classpath cp ->
String gradleHome = gradle.getGradleHomeDir().absolutePath.replace(File.separator, '/')
String gradleSrc = "${gradleHome}/src"

cp.entries.each {ClasspathEntry entry ->
if ((entry in AbstractLibrary) && (entry.library.file.name.startsWith('gradle-'))) {
entry.sourcePath = new org.gradle.plugins.ide.eclipse.model.internal.FileReferenceFactory().fromPath(gradleSrc)
}
}
}
}
}
}

Cheers,
Rolf

Thanks for your workaround, Rolf. That worked for me. Of course, it would be desirable for Gradle to do that automatically before 1.0 is released

Best regards,
Mike

Seems to be a duplicate of GRADLE-1219

When using the Gradle Wrapper then only the binary version of Gradle is downloaded to $GRADLE_USER_HOME (e.g. C:\Users\<user>\.gradle\wrapper\dists)
The workaround described above will create a "sourcepath" that point to a non existent directory (e.g. "C:/Users/<user>/.gradle/wrapper/dists/gradle-1.10-bin/qtvcssosa3asn4t6njd64fm3i/gradle-1.10/src")

Thus, when using the Gradle Wrapper we need to improve the workaround described above:

task wrapper(type: Wrapper) {
	gradleVersion = '1.10'
	// Get gradle-all distribution that contains not only the binaries but also the sources.
	distributionUrl = 'http://services.gradle.org/distributions/gradle-1.10-all.zip'
}

import org.gradle.plugins.ide.eclipse.model.*
eclipse {
	classpath {
		file {
			whenMerged {Classpath cp ->
				String gradleHome = gradle.getGradleHomeDir().absolutePath.replace(File.separator, '/')
				String gradleSrc = "${gradleHome}/src"
				cp.entries.each {ClasspathEntry entry ->
					if ((entry in AbstractLibrary) && (entry.library.file.name.startsWith('gradle-'))) {
						def matcher = entry.library.file.name =~ "gradle-(.*)-(.*)"
						String sourcePath= gradleSrc + '/' + matcher[0][1];
						entry.sourcePath = new org.gradle.plugins.ide.eclipse.model.internal.FileReferenceFactory().fromPath(sourcePath)
					}
				}
			}
		}
	}
}

I'm not sure it's 100% related, but there is a known bug about not seeing source code of third party dependencies, and a workaround is listed here -> http://stackoverflow.com/questions/12836089/why-is-eclipse-not-attaching-3rd-party-libs-source-files-to-a-wtp-faceted-gradle

While IntelliJ seems to be able to attach sources, eclipse still does not. Is that maybe a bug to be filed at the Buildship bugtracker?

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Thanks again for reporting this issue. We haven't heard back from you after our inquiry from November 15th. We are closing this issue now. Please create an issue on GitHub if you still feel passionate about getting it resolved.