error when using passThrough  #1658

when using the passThrough options I would expect the tsc command arguments to not comport the list of files to compile otherwise the tsc command produce this error:
error TS5042: Option 'project' cannot be mixed with source files on a command line.

Expected Behaviour

/path/to/tsc --project /path/to/tsconfig.json

Actual Behaviour

Actually the command adds the list of files first
/path/to/tsc file1.ts file2.ts --project /path/to/tsconfig.json

Steps to Reproduce the Problem

here's the config I use in gruntfile:
editor: { tsconfig: { tsconfig: path.normalize(path.resolve('./tsconfig.json')), passThrough: true },