add test for compiler output when compiling with rustc/clippy-driver
add test for compiler output when compiling with rustc/clippy-driver

aidancully/rust,graydon/rust,graydon/rust,graydon/rust,aidancully/rust,aidancully/rust,graydon/rust,aidancully/rust,graydon/rust,aidancully/rust,graydon/rust,aidancully/rust