The run-make test suite

The run-make test suite contains tests which are the most flexible out of all the rust-lang/rust test suites. run-make tests can basically contain arbitrary code, and are supported by the run_make_support library.

Infrastructure

A run-make test is a test recipe source file rmake.rs accompanied by its parent directory (e.g. tests/run-make/foo/rmake.rs is the foo run-make test).

The implementation for collecting and building the rmake.rs recipes are in src/tools/compiletest/src/runtest.rs, in run_rmake_test.

The setup for the rmake.rs can be summarized as a 3-stage process:

1. First, we build the run_make_support library in bootstrap as a tool lib.

2. Then, we compile the rmake.rs "recipe" linking the support library and its dependencies in, and provide a bunch of env vars. We setup a directory structure within build/<target>/test/run-make/

   <test-name>/
       rmake.exe              # recipe binary
       rmake_out/             # sources from test sources copied over
   

   and copy non-rmake.rs input support files over to rmake_out/. The support library is made available as an extern prelude.

3. Finally, we run the recipe binary and set rmake_out/ as the working directory.