VirtualInputs returns paths extracted from virtualInputFlags.

ClangParser parses clang command args to produce a CommandFlags object.

Preprocessor is the preprocessor of clang cpp compile actions.

CPPDependencyScanner is an interface to dependency scanner which provides functionality to find input dependencies given a compile command.

VirtualInputsProcessor processes the flags and aappends virtual inputs to command's InputSpec.

StdoutToResourceDirMapper maps clang output to resourceDir.