can't build futures_util in some cases

[bbigras]

crate2nix 0.7.0-beta.1

[dependencies]
futures = { version = "0.3", default-features = false, features = ["compat"] }
futures01 = { package = "futures", version = "0.1" }

fn main() {
    println!("Hello, world!");
}

Building src/lib.rs (futures_util)
Running rustc --crate-name futures_util src/lib.rs --out-dir target/lib --emit=dep-info,link -L dependency=target/deps --cap-lints allow -C opt-level=3 -C codegen-units=4 --extern futures_01=/nix/store/fy357naqvcp32pwzvfsy8js2656cg3mz-rust_futures-0.1.29-lib/lib/libfutures-b4d31530db.rlib --extern futures_channel=/nix/store/8fawwkmsfka609mrpvh2zkv9xxigsc4i-rust_futures-channel-0.3.1-lib/lib/libfutures_channel-89d404dce0.rlib --extern futures_core=/nix/store/3mkq50ackk1mabrr4jsw4wgxy3r7fywa-rust_futures-core-0.3.1-lib/lib/libfutures_core-b242c18f17.rlib --extern futures_io=/nix/store/8l7aykr100h7wimgq6x533gxgxaj6df0-rust_futures-io-0.3.1-lib/lib/libfutures_io-20eec2fb3b.rlib --extern futures_sink=/nix/store/7k45qsgp7dvs9rwd0p87xhjfb1dmwwjz-rust_futures-sink-0.3.1-lib/lib/libfutures_sink-86f23fc531.rlib --extern futures_task=/nix/store/3nrnys0pvza4asnyzbawczs8jfspr3ll-rust_futures-task-0.3.1-lib/lib/libfutures_task-53a5ce36f5.rlib --extern memchr=/nix/store/cymqzvxvzigisa8q1isjdqqx5y0rm9dx-rust_memchr-2.3.0-lib/lib/libmemchr-ff22be23c8.rlib --extern pin_utils=/nix/store/741ijdwd1w9lcrqp8bim3spkg64r6r6a-rust_pin-utils-0.1.0-alpha.4-lib/lib/libpin_utils-f799508eca.rlib --extern slab=/nix/store/pf4w8jhfbjia2q45ipd0y3z6c2sfnf93-rust_slab-0.4.2-lib/lib/libslab-d13bd9d52c.rlib --cfg feature="alloc" --cfg feature="async-await" --cfg feature="async-await-macro" --cfg feature="channel" --cfg feature="compat" --cfg feature="futures-channel" --cfg feature="futures-core/alloc" --cfg feature="futures-core/std" --cfg feature="futures-io" --cfg feature="futures-macro" --cfg feature="futures-sink" --cfg feature="futures-task/alloc" --cfg feature="futures-task/std" --cfg feature="futures_01" --cfg feature="io" --cfg feature="memchr" --cfg feature="proc-macro-hack" --cfg feature="proc-macro-nested" --cfg feature="sink" --cfg feature="slab" --cfg feature="std" --edition 2018 -C metadata=2d5950350b -C extra-filename=-2d5950350b --crate-type lib --color always
error[E0432]: unresolved import `proc_macro_hack`
 --> src/async_await/join_mod.rs:3:5
  |
3 | use proc_macro_hack::proc_macro_hack;
  |     ^^^^^^^^^^^^^^^ use of undeclared type or module `proc_macro_hack`

error[E0432]: unresolved import `proc_macro_hack`
 --> src/async_await/select_mod.rs:3:5
  |
3 | use proc_macro_hack::proc_macro_hack;
  |     ^^^^^^^^^^^^^^^ use of undeclared type or module `proc_macro_hack`

error[E0432]: unresolved import `futures_macro`
   --> src/async_await/select_mod.rs:162:13
    |
162 |     pub use futures_macro::select;
    |             ^^^^^^^^^^^^^ use of undeclared type or module `futures_macro`

error[E0432]: unresolved import `futures_macro`
  --> src/async_await/join_mod.rs:81:13
   |
81 |     pub use futures_macro::try_join;
   |             ^^^^^^^^^^^^^ use of undeclared type or module `futures_macro`

error[E0432]: unresolved import `futures_macro`
  --> src/async_await/join_mod.rs:78:13
   |
78 |     pub use futures_macro::join;
   |             ^^^^^^^^^^^^^ use of undeclared type or module `futures_macro`

error: cannot determine resolution for the attribute macro `proc_macro_hack`
   --> src/async_await/select_mod.rs:161:7
    |
161 |     #[proc_macro_hack(support_nested)]
    |       ^^^^^^^^^^^^^^^
    |
    = note: import resolution is stuck, try simplifying macro imports

error: cannot determine resolution for the attribute macro `proc_macro_hack`
  --> src/async_await/join_mod.rs:80:7
   |
80 |     #[proc_macro_hack(support_nested)]
   |       ^^^^^^^^^^^^^^^
   |
   = note: import resolution is stuck, try simplifying macro imports

error: cannot determine resolution for the attribute macro `proc_macro_hack`
  --> src/async_await/join_mod.rs:77:7
   |
77 |     #[proc_macro_hack(support_nested)]
   |       ^^^^^^^^^^^^^^^
   |
   = note: import resolution is stuck, try simplifying macro imports

error: aborting due to 8 previous errors

For more information about this error, try `rustc --explain E0432`.
builder for '/nix/store/kxngwa4nxvkb59f69fbjvcf87na5wz0r-rust_futures-util-0.3.1.drv' failed with exit code 1
cannot build derivation '/nix/store/4pv8kbnfgl8ixkx5wsyi06wz317gs1f8-rust_test-crate2nix-0.1.0.drv': 1 dependencies couldn't be built
error: build of '/nix/store/4pv8kbnfgl8ixkx5wsyi06wz317gs1f8-rust_test-crate2nix-0.1.0.drv' failed

[kolloch]

Thank you for the report and the sample! I could reproduce it and I think that it is something that is useful and should be supported.

I also verified quickly that each of these dependencies builds seperately.

The generated code is already quite obviously wrong:

{
        # ...
        dependencies = [
          {
            name = "futures";
            packageId = "futures 0.1.29";
            usesDefaultFeatures = false;
            features = [ "compat" ];
          }
          {
            name = "futures";
            packageId = "futures 0.1.29";
            rename = "futures01";
          }
          {
            name = "futures";
            packageId = "futures 0.3.4";
            usesDefaultFeatures = false;
            features = [ "compat" ];
          }
          {
            name = "futures";
            packageId = "futures 0.3.4";
            rename = "futures01";
          }
        ];
}

The rename support in buildRustCrate is keyed by crate name so it will also be a problem:

       let # ...
            crateRenames =
              builtins.listToAttrs
                (map (d: { name = d.name; value = d.rename; }) dependenciesWithRenames);
        in 
           # This is the `buildRustCrate` call -- just that users can override it.
           buildRustCrateFunc (
              crateConfig // {
                src = crateConfig.src or (
                  pkgs.fetchurl {
                    name = "${crateConfig.crateName}-${crateConfig.version}.tar.gz";
                    url = "https://crates.io/api/v1/crates/${crateConfig.crateName}/${crateConfig.version}/download";
                    sha256 = crateConfig.sha256;
                  }
                );
                inherit features dependencies buildDependencies crateRenames release;
              }
            )

[kolloch]

I have fixed this but I need to wait for the related nixpkgs review and eventual merge: NixOS/nixpkgs#84179

cargo metadata makes this rediculously difficult. I had to rematch the version requirements of the dependencies against the resolved packages for a package.

10d8de9

[bbigras]

It seems I'm not able to reproduce with my test case. Thanks!

[kolloch]

In #51, it seems like this issue is occurring again.

The generated code in Cargo.nix looks as expected:

      "futures-renamed-test" = rec {
        crateName = "futures-renamed-test";
        version = "0.1.0";
        edition = "2018";
        crateBin = [
          { name = "futures-renamed-test"; path = "src/main.rs"; }
        ];
        src = lib.cleanSourceWith { filter = sourceFilter;  src = ./.; };
        authors = [
          "Peter Kolloch <info@eigenvalue.net>"
        ];
        dependencies = [
          {
            name = "futures";
            packageId = "futures 0.1.29";
            rename = "futures01";
          }
          {
            name = "futures";
            packageId = "futures 0.3.5";
            usesDefaultFeatures = false;
            features = [ "compat" ];
          }
        ];
        
      };

[kolloch]

Hah! I didn't merge the fix to the master. That explains why it doesn't work. The integration test wasn't yet activated.

Thank you for your insistance, @bbigras. I merge the fix now, sorry.

[bbigras]

hehe.

It works and now I can use crate2nix with another project. Sweet.

Thank you very much!