ok, given https://github.com/pantsbuild/pants/blob/master/examples/src/resources/org/pantsbuild/example/hello/BUILD and https://github.com/pantsbuild/pants/blob/master/examples/src/java/org/pantsbuild/example/hello/main/BUILD how do you decide what is the root of the resources as used here : https://github.com/pantsbuild/pants/blob/master/examples/src/java/org/pantsbuild/example/hello/main/HelloMain.java#L17 and transitively here https://github.com/pantsbuild/pants/blob/master/examples/src/java/org/pantsbuild/example/hello/greet/Greeting.java#L24 ?

src/resources

is picked by https://github.com/pantsbuild/pants/blob/master/src/python/pants/source/source_root.py#L173

Stepping back, on of the main thrusts of pants from day one was to be able to take a large source tree and divide it up into fine grained targets. In this case you have 1 source tree with many (hundreds or thousands) of build files down in the tree. In that case the BUILD files do not live in the source root - it's seperate up higher, at - say - src/java.

yeah but since you declare the resources relative to the build file location I thought sources where find this way

OK. I don't follow the details - but Intellij has the exact same concept. You mark directories source roots, test roots, resource roots, etc.

yes but without manually specifying anything, using the pants plugin, intellij extract an "idea config" from "pants config" and mark some directories he identified as source root. And in a certain context that is out of the standards it was completely messed up. But your explanation give a whole new light on this !