rewrite pretty-print-to-file to rmake

Author: Oneirical

src/tools/tidy/src/allowed_run_make_makefiles.txt

@@ -84,7 +84,6 @@ run-make/jobserver-error/Makefile
 run-make/libs-through-symlinks/Makefile
 run-make/libtest-json/Makefile
 run-make/libtest-junit/Makefile
-run-make/libtest-padding/Makefile
 run-make/libtest-thread-limit/Makefile
 run-make/link-cfg/Makefile
 run-make/link-framework/Makefile
@@ -133,7 +132,6 @@ run-make/pgo-gen/Makefile
 run-make/pgo-indirect-call-promotion/Makefile
 run-make/pgo-use/Makefile
 run-make/pointer-auth-link-with-c/Makefile
-run-make/pretty-print-to-file/Makefile
 run-make/print-calling-conventions/Makefile
 run-make/print-target-list/Makefile
 run-make/profile/Makefile

tests/run-make/pretty-print-to-file/Makefile

@@ -0,0 +1,12 @@
+// The "pretty-printer" of rustc translates source code into other formats,
+// which is useful for debugging. This test checks the "normal" version of
+// -Zunpretty, which should format the poorly formatted input.rs into a one-line
+// function identical to the one in input.pp.
+// See https://github.com/rust-lang/rust/commit/da25539c1ab295ec40261109557dd4526923928c
+
+use run_make_support::{diff, rustc};
+
+fn main() {
+    rustc().output("input.out").arg("-Zunpretty=normal").input("input.rs").run();
+    diff().expected_file("input.out").actual_file("input.pp").run();
+}