Xcode fails to inherit PATH and therefore fails to find nix-installed cargo

[n8henrie]

I've successfully run cargo build --package shared && cargo build --package shared_types and opened the project in xcode.

In Xcode, attempting to build gives multiple errors, the first of which is:

RuleScriptExecution /Users/n8henrie/git/crux/examples/counter/iOS/generated/shared.swift /Users/n8henrie/git/crux/examples/counter/iOS/generated/sharedFFI.h /Users/n8henrie/git/crux/examples/counter/shared/src/shared.udl normal undefined_arch (in target 'CounterApp' from project 'CounterApp')
    cd /Users/n8henrie/git/crux/examples/counter/iOS
    /bin/sh -c \#\!/bin/bash'
'set\ -e'
''
'\#\ Skip\ during\ indexing\ phase\ in\ XCode\ 13+'
'if\ \[\ \"\$ACTION\"\ \=\=\ \"indexbuild\"\ \]\;\ then'
'\ \ echo\ \"Not\ building\ \*.udl\ files\ during\ indexing.\"'
'\ \ exit\ 0'
'fi'
''
'\#\ Skip\ for\ preview\ builds'
'if\ \[\ \"\$ENABLE_PREVIEWS\"\ \=\ \"YES\"\ \]\;\ then'
'\ \ echo\ \"Not\ building\ \*.udl\ files\ during\ preview\ builds.\"'
'\ \ exit\ 0'
'fi'
''
'cd\ \"\$\{INPUT_FILE_DIR\}/..\"'
'\"\$\{BUILD_DIR\}/debug/uniffi-bindgen\"\ generate\ \"src/\$\{INPUT_FILE_NAME\}\"\ --language\ swift\ --out-dir\ \"\$\{PROJECT_DIR\}/generated\"'
'

/bin/sh: line 16: /Users/n8henrie/Library/Developer/Xcode/DerivedData/CounterApp-fwwrdheqxdkprxbqjomnsznablpm/Build/Products/debug/uniffi-bindgen: No such file or directory
Command RuleScriptExecution failed with a nonzero exit code

Looking through a few other errors, I suspect this may be because I'm using a nix-installed cargo:

$ type -p cargo
/run/current-system/sw/bin/cargo

If the xcode build scripts are trying to call cargo commands, my recollection is that xcode won't necessarily have cargo in its path; some people also search for a rustup-installed cargo at ~/.cargo/bin or a brew-installed cargo at /opt/homebrew/bin (or /usr/local), but there are other possibilities.

Maybe related: #83

[StuartHarris]

Hey thank you for submitting this! And apologies for slow response.

We use Mozilla's uniffi to help with the bindings generation. To help with version matching, we build the tool as a binary within the shared crate (see https://github.com/redbadger/crux/blob/master/examples/counter/shared/src/bin/uniffi-bindgen.rs), and your script seems to be failing because it can't find this uniffi executable (rather than the cargo executable). I'm not too familiar with nix, but it may be that you need to edit the script to point to the built uniffi binary.

Hope this helps, but LMK if you're still struggling.
Thanks

[n8henrie]

Problem 1: cargo-xcode's build script uses a fixed PATH that won't work with alternative cargo install locations: https://gitlab.com/kornelski/cargo-xcode/-/blob/f202f751790b1e36571a0fe48a85ad35a3541ead/src/xcodebuild.sh#L2. Slight annoyance, easy fix.
Problem 2: It did not like using a faster linker (link-arg=-fuse-ld=lld), also an easy fix

With these two small fixes the iOS project builds and runs.

Because these will only affect a fairly niche set of users I don't think any code changes on crux's side are indicated, hopefully this issue will help if others run into similar issues. Will update the title for better searchability.

Thanks for a cool project!