cargo fix: "Cannot replace slice of data that was already replaced"

[ExpHP]

Source code

Instructions in README.md.

---

cargo fix output

$ touch src/lib.rs && cargo +nightly fix --prepare-for 2018 --all-targets --all-features --allow-dirty
    Updating registry `https://github.com/rust-lang/crates.io-index`
    Updating git repository `https://github.com/rust-lang-nursery/failure`                                                                  
    Updating git repository `https://github.com/withoutboats/display_derive`                                                                
    Checking rsp2-assert-close v0.1.0 (file:///home/lampam/asd/rsp2-test-case/rsp2-assert-close)                                            
    Checking rsp2-minimize v0.1.0 (file:///home/lampam/asd/rsp2-test-case/rsp2-minimize)
warning: error applying suggestions to `src/acgsd.rs`

The full error message was:

> Cannot replace slice of data that was already replacedThis 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/cargo/issues
quoting the full output of this command we'd be very appreciative!

warning: absolute paths must start with `self`, `super`, `crate`, or an external crate name in the 2018 edition
   --> src/acgsd.rs:339:17
    |
339 |             use ::stop_condition::Cereal::{Simple,Logical};
    |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use `crate`: `crate::stop_condition::Cereal::{Simple,Logical}`
    |
    = note: `-W absolute-paths-not-starting-with-crate` implied by `-W rust-2018-compatibility`
    = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in the 2018 edition!
    = note: for more information, see issue TBD

warning: absolute paths must start with `self`, `super`, `crate`, or an external crate name in the 2018 edition
   --> src/acgsd.rs:340:17
    |
340 |             use ::stop_condition::LogicalExpression::All;
    |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use `crate`: `crate::stop_condition::LogicalExpression::All`
    |
    = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in the 2018 edition!
    = note: for more information, see issue TBD

warning: absolute paths must start with `self`, `super`, `crate`, or an external crate name in the 2018 edition
   --> src/acgsd.rs:968:9
    |
968 |     use ::util::Never;
    |         ^^^^^^^^^^^^^ help: use `crate`: `crate::util::Never`
    |
    = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in the 2018 edition!
    = note: for more information, see issue TBD

warning: absolute paths must start with `self`, `super`, `crate`, or an external crate name in the 2018 edition
    --> src/acgsd.rs:1008:13
     |
1008 |         use ::util::random::uniform_n;
     |             ^^^^^^^^^^^^^^^^^^^^^^^^^ help: use `crate`: `crate::util::random::uniform_n`
     |
     = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in the 2018 edition!
     = note: for more information, see issue TBD

warning: absolute paths must start with `self`, `super`, `crate`, or an external crate name in the 2018 edition
    --> src/acgsd.rs:978:17
     |
978  |             use ::test::one_dee::prelude::*;
     |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use `crate`: `crate::test::one_dee::prelude::*`
...
1013 |         let result = super::acgsd(&settings, &initial_point, quadratic_test_fn!(&target)).unwrap();
     |                                                              --------------------------- in this macro invocation
     |
     = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in the 2018 edition!
     = note: for more information, see issue TBD

warning: absolute paths must start with `self`, `super`, `crate`, or an external crate name in the 2018 edition
    --> src/acgsd.rs:979:17
     |
979  |             use ::test::one_dee::Polynomial;
     |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use `crate`: `crate::test::one_dee::Polynomial`
...
1013 |         let result = super::acgsd(&settings, &initial_point, quadratic_test_fn!(&target)).unwrap();
     |                                                              --------------------------- in this macro invocation
     |
     = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in the 2018 edition!
     = note: for more information, see issue TBD

warning: absolute paths must start with `self`, `super`, `crate`, or an external crate name in the 2018 edition
    --> src/acgsd.rs:1021:13
     |
1021 |         use ::util::random::uniform_n;
     |             ^^^^^^^^^^^^^^^^^^^^^^^^^ help: use `crate`: `crate::util::random::uniform_n`
     |
     = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in the 2018 edition!
     = note: for more information, see issue TBD

warning: absolute paths must start with `self`, `super`, `crate`, or an external crate name in the 2018 edition
    --> src/acgsd.rs:978:17
     |
978  |             use ::test::one_dee::prelude::*;
     |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use `crate`: `crate::test::one_dee::prelude::*`
...
1028 |         assert_eq!(super::acgsd(&s, &point, quadratic_test_fn!(&target)).unwrap().iterations, 0);
     |                                             --------------------------- in this macro invocation
     |
     = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in the 2018 edition!
     = note: for more information, see issue TBD

warning: absolute paths must start with `self`, `super`, `crate`, or an external crate name in the 2018 edition
    --> src/acgsd.rs:979:17
     |
979  |             use ::test::one_dee::Polynomial;
     |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use `crate`: `crate::test::one_dee::Polynomial`
...
1028 |         assert_eq!(super::acgsd(&s, &point, quadratic_test_fn!(&target)).unwrap().iterations, 0);
     |                                             --------------------------- in this macro invocation
     |
     = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in the 2018 edition!
     = note: for more information, see issue TBD

warning: absolute paths must start with `self`, `super`, `crate`, or an external crate name in the 2018 edition
    --> src/acgsd.rs:978:17
     |
978  |             use ::test::one_dee::prelude::*;
     |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use `crate`: `crate::test::one_dee::prelude::*`
...
1031 |         assert_eq!(super::acgsd(&s, &point, quadratic_test_fn!(&target)).unwrap().iterations, 0);
     |                                             --------------------------- in this macro invocation
     |
     = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in the 2018 edition!
     = note: for more information, see issue TBD

warning: absolute paths must start with `self`, `super`, `crate`, or an external crate name in the 2018 edition
    --> src/acgsd.rs:979:17
     |
979  |             use ::test::one_dee::Polynomial;
     |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use `crate`: `crate::test::one_dee::Polynomial`
...
1031 |         assert_eq!(super::acgsd(&s, &point, quadratic_test_fn!(&target)).unwrap().iterations, 0);
     |                                             --------------------------- in this macro invocation
     |
     = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in the 2018 edition!
     = note: for more information, see issue TBD

warning: absolute paths must start with `self`, `super`, `crate`, or an external crate name in the 2018 edition
    --> src/acgsd.rs:978:17
     |
978  |             use ::test::one_dee::prelude::*;
     |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use `crate`: `crate::test::one_dee::prelude::*`
...
1042 |         assert_eq!(super::acgsd(&s, &point, quadratic_test_fn!(&target)).unwrap().iterations, 2);
     |                                             --------------------------- in this macro invocation
     |
     = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in the 2018 edition!
     = note: for more information, see issue TBD

warning: absolute paths must start with `self`, `super`, `crate`, or an external crate name in the 2018 edition
    --> src/acgsd.rs:979:17
     |
979  |             use ::test::one_dee::Polynomial;
     |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use `crate`: `crate::test::one_dee::Polynomial`
...
1042 |         assert_eq!(super::acgsd(&s, &point, quadratic_test_fn!(&target)).unwrap().iterations, 2);
     |                                             --------------------------- in this macro invocation
     |
     = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in the 2018 edition!
     = note: for more information, see issue TBD

warning: absolute paths must start with `self`, `super`, `crate`, or an external crate name in the 2018 edition
    --> src/acgsd.rs:1053:13
     |
1053 |         use ::util::random::uniform_n;
     |             ^^^^^^^^^^^^^^^^^^^^^^^^^ help: use `crate`: `crate::util::random::uniform_n`
     |
     = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in the 2018 edition!
     = note: for more information, see issue TBD

warning: absolute paths must start with `self`, `super`, `crate`, or an external crate name in the 2018 edition
    --> src/acgsd.rs:978:17
     |
978  |             use ::test::one_dee::prelude::*;
     |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use `crate`: `crate::test::one_dee::prelude::*`
...
1061 |         let potential = scale_y!(1e-40, quadratic_test_fn!(&target));
     |                                         --------------------------- in this macro invocation
     |
     = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in the 2018 edition!
     = note: for more information, see issue TBD

warning: absolute paths must start with `self`, `super`, `crate`, or an external crate name in the 2018 edition
    --> src/acgsd.rs:979:17
     |
979  |             use ::test::one_dee::Polynomial;
     |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use `crate`: `crate::test::one_dee::Polynomial`
...
1061 |         let potential = scale_y!(1e-40, quadratic_test_fn!(&target));
     |                                         --------------------------- in this macro invocation
     |
     = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in the 2018 edition!
     = note: for more information, see issue TBD

warning: absolute paths must start with `self`, `super`, `crate`, or an external crate name in the 2018 edition
    --> src/acgsd.rs:978:17
     |
978  |             use ::test::one_dee::prelude::*;
     |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use `crate`: `crate::test::one_dee::prelude::*`
...
1069 |         let potential = scale_y!(1e+40, quadratic_test_fn!(&target));
     |                                         --------------------------- in this macro invocation
     |
     = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in the 2018 edition!
     = note: for more information, see issue TBD

warning: absolute paths must start with `self`, `super`, `crate`, or an external crate name in the 2018 edition
    --> src/acgsd.rs:979:17
     |
979  |             use ::test::one_dee::Polynomial;
     |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use `crate`: `crate::test::one_dee::Polynomial`
...
1069 |         let potential = scale_y!(1e+40, quadratic_test_fn!(&target));
     |                                         --------------------------- in this macro invocation
     |
     = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in the 2018 edition!
     = note: for more information, see issue TBD

warning: absolute paths must start with `self`, `super`, `crate`, or an external crate name in the 2018 edition
    --> src/acgsd.rs:1081:21
     |
1081 |         let point = ::util::random::uniform_n(18, -10.0, 10.0);
     |                     ^^^^^^^^^^^^^^^^^^^^^^^^^ help: use `crate`: `crate::util::random::uniform_n`
     |
     = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in the 2018 edition!
     = note: for more information, see issue TBD

warning: absolute paths must start with `self`, `super`, `crate`, or an external crate name in the 2018 edition
    --> src/acgsd.rs:1095:13
     |
1095 |         use ::util::random::uniform_n;
     |             ^^^^^^^^^^^^^^^^^^^^^^^^^ help: use `crate`: `crate::util::random::uniform_n`
     |
     = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in the 2018 edition!
     = note: for more information, see issue TBD

warning: absolute paths must start with `self`, `super`, `crate`, or an external crate name in the 2018 edition
    --> src/acgsd.rs:978:17
     |
978  |             use ::test::one_dee::prelude::*;
     |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use `crate`: `crate::test::one_dee::prelude::*`
...
1101 |         let result = super::acgsd(&settings, &start, quadratic_test_fn!(&target)).unwrap();
     |                                                      --------------------------- in this macro invocation
     |
     = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in the 2018 edition!
     = note: for more information, see issue TBD

warning: absolute paths must start with `self`, `super`, `crate`, or an external crate name in the 2018 edition
    --> src/acgsd.rs:979:17
     |
979  |             use ::test::one_dee::Polynomial;
     |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use `crate`: `crate::test::one_dee::Polynomial`
...
1101 |         let result = super::acgsd(&settings, &start, quadratic_test_fn!(&target)).unwrap();
     |                                                      --------------------------- in this macro invocation
     |
     = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in the 2018 edition!
     = note: for more information, see issue TBD

warning: absolute paths must start with `self`, `super`, `crate`, or an external crate name in the 2018 edition
    --> src/acgsd.rs:978:17
     |
978  |             use ::test::one_dee::prelude::*;
     |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use `crate`: `crate::test::one_dee::prelude::*`
...
1107 |         let result = super::acgsd(&settings, &start, quadratic_test_fn!(&target)).unwrap();
     |                                                      --------------------------- in this macro invocation
     |
     = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in the 2018 edition!
     = note: for more information, see issue TBD

warning: absolute paths must start with `self`, `super`, `crate`, or an external crate name in the 2018 edition
    --> src/acgsd.rs:979:17
     |
979  |             use ::test::one_dee::Polynomial;
     |                 ^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use `crate`: `crate::test::one_dee::Polynomial`
...
1107 |         let result = super::acgsd(&settings, &start, quadratic_test_fn!(&target)).unwrap();
     |                                                      --------------------------- in this macro invocation
     |
     = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in the 2018 edition!
     = note: for more information, see issue TBD

warning: absolute paths must start with `self`, `super`, `crate`, or an external crate name in the 2018 edition
    --> src/acgsd.rs:1114:13
     |
1114 |         use ::test::n_dee::{Trid, OnceDifferentiable};
     |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use `crate`: `crate::test::n_dee::{Trid, OnceDifferentiable}`
     |
     = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in the 2018 edition!
     = note: for more information, see issue TBD

warning: absolute paths must start with `self`, `super`, `crate`, or an external crate name in the 2018 edition
    --> src/acgsd.rs:1115:13
     |
1115 |         use ::util::random::uniform_n;
     |             ^^^^^^^^^^^^^^^^^^^^^^^^^ help: use `crate`: `crate::util::random::uniform_n`
     |
     = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in the 2018 edition!
     = note: for more information, see issue TBD

warning: absolute paths must start with `self`, `super`, `crate`, or an external crate name in the 2018 edition
    --> src/acgsd.rs:1133:13
     |
1133 |         use ::test::n_dee::{HyperLennardJones, OnceDifferentiable, Sum};
     |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: use `crate`: `crate::test::n_dee::{HyperLennardJones, OnceDifferentiable, Sum}`
     |
     = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in the 2018 edition!
     = note: for more information, see issue TBD

warning: absolute paths must start with `self`, `super`, `crate`, or an external crate name in the 2018 edition
    --> src/acgsd.rs:1134:13
     |
1134 |         use ::util::random as urand;
     |             ^^^^^^^^^^^^^^^^^^^^^^^ help: use `crate`: `crate::util::random as urand`
     |
     = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in the 2018 edition!
     = note: for more information, see issue TBD

    Finished dev [unoptimized + debuginfo] target(s) in 18.75s

---

Also, if you are interested, the first commit e718f5bc1 contains an example of the second issue mentioned in this post. I haven't created an issue for that one because it didn't seem like there was anything actionable from cargo's end.

[alexcrichton]

Thanks for the report! I think this should be fixed by rust-lang/rustfix#131 although it hasn't made its way into Cargo yet. I'll work on doing that and then swing back here to confirm this is fixed.

[alexcrichton]

Confirmed fixed!