fix: default to all targets when using --edition and --edition-idioms in cargo fix

[Rustin170506]

What does this PR try to resolve?

Close #13527

As we discussed, cargo fix should use the default target selection with cargo check.

In this PR, I modified cargo fix to no longer use all targets by default. For cargo fix --edition and cargo fix --edition-idioms, it will retain the old behavior and select all targets.

How should we test and review this PR?

Unit tests

Additional information

[rustbot]

r? @epage

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[epage]

As you said, this is suspicious and we should understand why in case there is a bad interaction happening

[Rustin170506]

Yes, I’m still looking into it. It seems that if we don’t select all targets, the foo rustc is called only twice. However, if we select all targets, it will be called three times, I believe.

[Rustin170506]

With all targets: p.cargo("fix --all-targets --allow-no-vcs --broken-code")

[COMPILING] bar v0.1.0 ([ROOT]/foo/bar)
[WARNING] failed to automatically apply fixes suggested by rustc to crate `bar`
This likely indicates a bug in either rustc or cargo itself,
and we would appreciate a bug report! You're likely to see
a number of compiler warnings after this message which cargo
attempted to fix but failed. If you could open an issue at
https://github.com/rust-lang/rust/issues
quoting the full output of this command we'd be very appreciative!
Note that you may be able to make some more progress in the near-term
fixing code with the `--broken-code` flag

The following errors were reported:

thread 'main' panicked at src/main.rs:23:29:
explicit panic
[NOTE] run with `RUST_BACKTRACE=1` environment variable to display a backtrace
Original diagnostics will follow.

[WARNING] variable does not need to be mutable
 --> src/lib.rs:1:20
  |
1 | pub fn foo() { let mut x = 3; let _ = x; }
  |                    ----^
  |                    |
  |                    [HELP] remove this `mut`
  |
  = [NOTE] `#[warn(unused_mut)]` on by default

[WARNING] `bar` (lib) generated 1 warning (run `cargo fix --lib -p bar` to apply 1 suggestion)

thread 'main' panicked at src/main.rs:23:29:
explicit panic
[NOTE] run with `RUST_BACKTRACE=1` environment variable to display a backtrace
[ERROR] could not compile `bar` (lib test)

Caused by:
  process didn't exit successfully: `/Volumes/t7/code/cargo/target/debug/cargo [ROOT]/foo/foo/target/debug/foo --crate-name bar --edition=2015 src/lib.rs --error-format=json --json=diagnostic-rendered-ansi,artifacts,future-incompat --emit=dep-info,metadata -C embed-bitcode=no -C debuginfo=2 -C split-debuginfo=unpacked --test --check-cfg 'cfg(docsrs,test)' --check-cfg 'cfg(feature, values())' -C metadata=022767cbb3148d36 -C extra-filename=-99a4e0453221de9d --out-dir [ROOT]/foo/bar/target/debug/deps -L dependency=[ROOT]/foo/bar/target/debug/deps` ([EXIT_STATUS]: 101)

Without all targets: p.cargo("fix --allow-no-vcs --broken-code")

[COMPILING] bar v0.1.0 ([ROOT]/foo/bar)
[WARNING] failed to automatically apply fixes suggested by rustc to crate `bar`
This likely indicates a bug in either rustc or cargo itself,
and we would appreciate a bug report! You're likely to see
a number of compiler warnings after this message which cargo
attempted to fix but failed. If you could open an issue at
https://github.com/rust-lang/rust/issues
quoting the full output of this command we'd be very appreciative!
Note that you may be able to make some more progress in the near-term
fixing code with the `--broken-code` flag

The following errors were reported:

thread 'main' panicked at src/main.rs:23:29:
explicit panic
[NOTE] run with `RUST_BACKTRACE=1` environment variable to display a backtrace
Original diagnostics will follow.

[WARNING] variable does not need to be mutable
 --> src/lib.rs:1:20
  |
1 | pub fn foo() { let mut x = 3; let _ = x; }
  |                    ----^
  |                    |
  |                    [HELP] remove this `mut`
  |
  = [NOTE] `#[warn(unused_mut)]` on by default

[WARNING] `bar` (lib) generated 1 warning (run `cargo fix --lib -p bar` to apply 1 suggestion)
[FINISHED] `dev` profile [unoptimized + debuginfo] target(s) in [ELAPSED]s

[Rustin170506]

And if you have two targets, it also works: p.cargo("fix --lib --tests --allow-no-vcs --broken-code")

[COMPILING] bar v0.1.0 ([ROOT]/foo/bar)
[WARNING] failed to automatically apply fixes suggested by rustc to crate `bar`
This likely indicates a bug in either rustc or cargo itself,
and we would appreciate a bug report! You're likely to see
a number of compiler warnings after this message which cargo
attempted to fix but failed. If you could open an issue at
https://github.com/rust-lang/rust/issues
quoting the full output of this command we'd be very appreciative!
Note that you may be able to make some more progress in the near-term
fixing code with the `--broken-code` flag

The following errors were reported:

thread 'main' panicked at src/main.rs:23:29:
explicit panic
[NOTE] run with `RUST_BACKTRACE=1` environment variable to display a backtrace
Original diagnostics will follow.

[WARNING] variable does not need to be mutable
 --> src/lib.rs:1:20
  |
1 | pub fn foo() { let mut x = 3; let _ = x; }
  |                    ----^
  |                    |
  |                    [HELP] remove this `mut`
  |
  = [NOTE] `#[warn(unused_mut)]` on by default

[WARNING] `bar` (lib test) generated 1 warning (run `cargo fix --lib -p bar --tests` to apply 1 suggestion)

thread 'main' panicked at src/main.rs:23:29:
explicit panic
[NOTE] run with `RUST_BACKTRACE=1` environment variable to display a backtrace
[ERROR] could not compile `bar` (lib)

Caused by:
  process didn't exit successfully: `/Volumes/t7/code/cargo/target/debug/cargo [ROOT]/foo/foo/target/debug/foo --crate-name bar --edition=2015 src/lib.rs --error-format=json --json=diagnostic-rendered-ansi,artifacts,future-incompat --crate-type lib --emit=dep-info,metadata -C embed-bitcode=no -C debuginfo=2 -C split-debuginfo=unpacked --check-cfg 'cfg(docsrs,test)' --check-cfg 'cfg(feature, values())' -C metadata=4b0938be085d245b -C extra-filename=-d245623a02104f1e --out-dir [ROOT]/foo/bar/target/debug/deps -L dependency=[ROOT]/foo/bar/target/debug/deps` ([EXIT_STATUS]: 101)

[Rustin170506]

I think it’s related to how many times foo rustc is called in this command. If it’s called only twice for one target, the panic error is caught as a warning. However, if it’s called again, it turns into a compile error and causes a bailout. Then the status becomes 101.
I’ll dig into it further. I’m not sure how we handle the compile error here, but I’ll take a look tomorrow.

[Rustin170506]

I think this change is reasonable. The test returns a 101 status because rustc was called three times. The first time, it attempts to fix build.rs with no errors. The second time, it tries to fix src/lib.rs, where there is one error, but we have a mechanism to output the errors as warnings when --broekn-code was specified.

cargo/src/cargo/ops/fix.rs

Lines 720 to 723 in 99745f0

	// Exit with whatever exit code we initially started with. `cargo fix`
	// treats this as a warning, and shouldn't return a failure code
	// unless the code didn't compile in the first place.
	exit_with(fixes.first_output.status);

The third time, it attempts to fix src/lib.rs again, but since no fixes are needed, the panic error is displayed directly, resulting in the 101 status.

cargo/src/cargo/ops/fix.rs

Line 695 in 99745f0

if fixes.files.is_empty() {

[Rustin170506]

I think we should remove --all-target. The status 0 is expected here

[epage]

@ehuss any idea what this test should be doing?