rs

The rs spell wires Cargo into a magusfile. Each op forks a cargo subcommand directly; cargo-build builds in release mode and cargo-clippy denies warnings, matching a CI-gating default.

Runtime name: rs (source spells/rust/)

Version probe: rustc --version

Passing arguments to ops

Every op is invoked as rs["<op>"](ctx, opts?). The first argument is the target's context, which is what carries the execution environment; the optional options map shapes the command itself:

Working directory and environment are NOT options: they ride the context, as rs["<op>"](ctx.withCwd("sub")) and rs["<op>"](ctx.withEnv({"CGO_ENABLED": "0"})). Only the context reaches the cache key, so an option-table cwd or env would change what the tool did while the key said otherwise - passing either as an option is an error.

Charms (the :charm suffix, e.g. magus run test:rw) are orthogonal: they patch the base argv, while these options add to it. See Charms.

cargo-build

Command: cargo build --release

Example

// cargo-build compiles in release mode: magus run build forks cargo build --release.
import "magus";
import "magus/spell/rs";

magus\project({ "spells": [rs] });

export fun build(ctx: magus\Context, args: [str]) > void {
    rs["cargo-build"](ctx);
}

cargo-clean

Command: cargo clean

Example

// Wire cargo-clean into a clean target: magus run clean forks cargo clean.
import "magus";
import "magus/spell/rs";

magus\project({ "spells": [rs] });

export fun clean(ctx: magus\Context, args: [str]) > void {
    rs["cargo-clean"](ctx);
}

cargo-clippy

Command: cargo clippy -- -D warnings

Example

// cargo-clippy lints and denies warnings (-D warnings), gating CI on a clean run.
import "magus";
import "magus/spell/rs";

magus\project({ "spells": [rs] });

export fun clippy(ctx: magus\Context, args: [str]) > void {
    rs["cargo-clippy"](ctx);
}

cargo-fmt

Command: cargo fmt -- --check

rw

Drops --check, drops --.

[
  {
    "op": "remove",
    "path": "/2"
  },
  {
    "op": "remove",
    "path": "/1"
  }
]

Example

// cargo-fmt checks formatting; the rw charm (magus run format:rw) rewrites in place.
import "magus";
import "magus/spell/rs";

magus\project({ "spells": [rs] });

export fun format(ctx: magus\Context, args: [str]) > void {
    rs["cargo-fmt"](ctx);
}

cargo-test

Command: cargo test

Example

// Wire cargo-test into a test target: magus run test forks cargo test.
import "magus";
import "magus/spell/rs";

magus\project({ "spells": [rs] });

export fun test(ctx: magus\Context, args: [str]) > void {
    rs["cargo-test"](ctx);
}

scip

scip is the reserved op that runs the Rust SCIP indexer for the knowledge graph. magus injects MAGUS_SYMBOL_INDEX with the cache destination, so the index never lands in the tree; rust-analyzer's scip subcommand writes there via --output. Run through sh so the env var expands.

Command: sh -c rust-analyzer scip . --output "$MAGUS_SYMBOL_INDEX"