Address comments from PR #8418.

[pnkfelix]

Comments addressed were:

• nit: we prefer "expected foo, found bar" to "expected foo but found bar"
• nit: lowercase initial letter of error message
  • (i fixed other instances of this in the file that were not part of the original PR)
• "just do let _ = s;" (for suppressing unused variable warning).

[emberian]

rollup candidate

[pnkfelix]

�So now I'm torn. Maybe this could land with a simply bors retry; I cannot tell from the error message. But it such a minor patch, maybe it should just be put into a rollup instead. Since I cannot decide between those options (and am not inclined to do a roll-up myself), I have just left this PR open.

But then, Graydon asked recently for people to close failed PR's in order to bring down the amount that bors stresses the github API (since it was hitting the rate limit). So now it seems like even leaving the PR open is not a great choice. (But the changes are legitimate, so I don't want to close it unless I can convince myself that I will repost it later...)

Sigh.

[huonw]

I think this requires some little clean-ups to make the test-cases' error patterns match rustc's.

The error pattern is Unit-like ..., but the error message is unit-like ... (same for all the struct-no-fields tests)

error: error pattern ' Unit-like struct construction is written with no trailing `{ }`' not found!
command: x86_64-unknown-linux-gnu/stage2/bin/rustc /home/rustbuild/src/rust-buildbot/slave/auto-linux-64-nopt-t/build/src/test/compile-fail/struct-no-fields-4.rs -o x86_64-unknown-linux-gnu/test/compile-fail/struct-no-fields-4.stage2-x86_64-unknown-linux-gnu -L x86_64-unknown-linux-gnu/test/compile-fail -L x86_64-unknown-linux-gnu/test/compile-fail/struct-no-fields-4.stage2-x86_64-unknown-linux-gnu.libaux --target=x86_64-unknown-linux-gnu
stdout:
------------------------------------------

------------------------------------------
stderr:
------------------------------------------
/home/rustbuild/src/rust-buildbot/slave/auto-linux-64-nopt-t/build/src/test/compile-fail/struct-no-fields-4.rs:15:32: 15:33 error: unit-like struct construction is written with no trailing `{ }`
/home/rustbuild/src/rust-buildbot/slave/auto-linux-64-nopt-t/build/src/test/compile-fail/struct-no-fields-4.rs:15     let _end_of_tuple = (3, Foo { });

A missing comma:

error: unexpected compiler error or warning: '/home/rustbuild/src/rust-buildbot/slave/auto-linux-64-nopt-t/build/src/test/compile-fail/issue-3036.rs:16:0: 16:1 error: expected `;`, found `}`'
command: x86_64-unknown-linux-gnu/stage2/bin/rustc /home/rustbuild/src/rust-buildbot/slave/auto-linux-64-nopt-t/build/src/test/compile-fail/issue-3036.rs -o x86_64-unknown-linux-gnu/test/compile-fail/issue-3036.stage2-x86_64-unknown-linux-gnu -L x86_64-unknown-linux-gnu/test/compile-fail -L x86_64-unknown-linux-gnu/test/compile-fail/issue-3036.stage2-x86_64-unknown-linux-gnu.libaux --target=x86_64-unknown-linux-gnu
stdout:
------------------------------------------

------------------------------------------
stderr:
------------------------------------------
/home/rustbuild/src/rust-buildbot/slave/auto-linux-64-nopt-t/build/src/test/compile-fail/issue-3036.rs:16:0: 16:1 error: expected `;`, found `}`
/home/rustbuild/src/rust-buildbot/slave/auto-linux-64-nopt-t/build/src/test/compile-fail/issue-3036.rs:16 } //~ ERROR: expected `;` but found `}`
                                                                                                          ^

[pnkfelix]

@huonw Ah, I misinterpreted the bors output (and thought that I had done a make check on my original commit...). Thanks for double-checking that for me.

[pnkfelix]

(closing until I can fix properly.)

[pnkfelix]

(part of #3192.)