factors: Add build script for factors smoke test app

Signed-off-by: Lann Martin <[email protected]>

crates/factors/Cargo.toml

@@ -31,5 +31,8 @@ tokio = { version = "1", features = ["macros", "rt", "sync"] }
 toml = "0.8"
 wasmtime-wasi-http = { workspace = true }
 
+[build-dependencies]
+cargo-target-dep = { git = "https://github.com/fermyon/cargo-target-dep", rev = "482f269eceb7b1a7e8fc618bf8c082dd24979cf1" }
+
 [lints]
 workspace = true

crates/factors/build.rs

@@ -0,0 +1,19 @@
+use std::path::Path;
+
+use cargo_target_dep::build_target_dep;
+
+fn main() {
+    println!("cargo:rerun-if-changed=build.rs");
+    // Enable spin-factors-derive to emit expanded macro output.
+    let out_dir = std::env::var("OUT_DIR").unwrap();
+    println!("cargo:rustc-env=SPIN_FACTORS_DERIVE_EXPAND_DIR={out_dir}");
+
+    let root = "tests/smoke-app";
+    build_target_dep(root, Path::new("tests/smoke-app/target/smoke_app.wasm"))
+        .release()
+        .target("wasm32-wasi")
+        .build();
+    println!("cargo:rerun-if-changed={root}/Cargo.toml");
+    println!("cargo:rerun-if-changed={root}/Cargo.lock");
+    println!("cargo:rerun-if-changed={root}/src");
+}

crates/factors/tests/smoke-app/spin.toml

@@ -15,11 +15,7 @@ route = "/..."
 component = "smoke-app"
 
 [component.smoke-app]
-source = "target/wasm32-wasi/release/smoke_app.wasm"
+source = "target/smoke_app.wasm"
 allowed_outbound_hosts = ["https://{{ host }}"]
 key_value_stores = ["default"]
-variables = { "other" = "<{{ other }}>"}
-
-[component.smoke-app.build]
-command = "cargo build --target wasm32-wasi --release"
-watch = ["src/**/*.rs", "Cargo.toml"]
+variables = { "other" = "<{{ other }}>"}