Fix `--nocapture` for run-make tests
This was confusing because there are three layers of output hiding.
1. libtest shoves all output into a buffer and does not print it unless the test fails or `--nocapture` is passed.
2. compiletest chooses whether to print the output from any given process.
3. run-make-support chooses what output to print.
This modifies 2 and 3.
- compiletest: Don't require both `--verbose` and `--nocapture` to show the output of run-make tests.
- compiletest: Print the output from `rmake` processes if they succeed. Previously this was only printed on failure.
- compiletest: Distinguish rustc and rmake stderr by printing the command name (e.g. "--stderr--" to "--rustc stderr--").
- run-make-support: Unconditionally print the needle/haystack being searched. Previously this was only printed on failure.
Before:
```
$ x t tests/run-make/linker-warning --force-rerun -- --nocapture
running 1 tests
.
test result: ok. 1 passed; 0 failed; 0 ignored; 0 measured; 377 filtered out; finished in 281.64ms
$ x t tests/run-make/linker-warning --force-rerun -v -- --nocapture 2>&1 | wc -l
1004
$ x t tests/run-make/linker-warning --force-rerun -v -- --nocapture | tail -n40
running 1 tests
------stdout------------------------------
------stderr------------------------------
warning: unused import: `std::path::Path`
--> /home/jyn/src/rust2/tests/run-make/linker-warning/rmake.rs:1:5
|
1 | use std::path::Path;
| ^^^^^^^^^^^^^^^
|
= note: `#[warn(unused_imports)]` on by default
warning: unused import: `run_make_support::rfs::remove_file`
--> /home/jyn/src/rust2/tests/run-make/linker-warning/rmake.rs:3:5
|
3 | use run_make_support::rfs::remove_file;
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
warning: 2 warnings emitted
------------------------------------------
test [run-make] tests/run-make/linker-warning ... ok
test result: ok. 1 passed; 0 failed; 0 ignored; 0 measured; 377 filtered out; finished in 285.89ms
```
After:
```
Testing stage1 compiletest suite=run-make mode=run-make (x86_64-unknown-linux-gnu)
running 1 tests
------rmake stdout------------------------------
------rmake stderr------------------------------
assert_contains_regex:
=== HAYSTACK ===
error: linking with `./fake-linker` failed: exit status: 1
|
= note: LC_ALL="C" PATH="/home/jyn/src/rust2/build/x86_64-unknown-linux-gnu/stage1/lib/rustlib/x86_64-unknown-linux-gnu/bin:...:/bin" VSLANG="1033" "./fake-linker" "-m64" "/tmp/rustcYqdAZT/symbols.o" "main.main.d17f5fbe6225cf88-cgu.0.rcgu.o" "main.2uoctswmurc6ir5rvoay0p9ke.rcgu.o" "-Wl,--as-needed" "-Wl,-Bstatic" "-Wl,-Bdynamic" "-lgcc_s" "-lutil" "-lrt" "-lpthread" "-lm" "-ldl" "-lc" "-B/home/jyn/src/rust2/build/x86_64-unknown-linux-gnu/stage1/lib/rustlib/x86_64-unknown-linux-gnu/bin/gcc-ld" "-fuse-ld=lld" "-Wl,--eh-frame-hdr" "-Wl,-z,noexecstack" "-L" "/home/jyn/src/rust2/build/x86_64-unknown-linux-gnu/test/run-make/linker-warning/rmake_out" "-L" "/home/jyn/src/rust2/build/x86_64-unknown-linux-gnu/stage1/lib/rustlib/x86_64-unknown-linux-gnu/lib" "-o" "main" "-Wl,--gc-sections" "-pie" "-Wl,-z,relro,-z,now" "-nodefaultlibs" "run_make_error"
= note: error: baz
error: aborting due to 1 previous error
=== NEEDLE ===
fake-linker.*run_make_error
assert_not_contains_regex:
=== HAYSTACK ===
=== NEEDLE ===
fake-linker.*run_make_error
------------------------------------------
.
test result: ok. 1 passed; 0 failed; 0 ignored; 0 measured; 377 filtered out; finished in 314.81ms
```
r? `@jieyouxu`
fdd0eb0e34