Build in debug mode by default

.gitignore

@@ -1,4 +1,4 @@
-/target
+target/
 javy.wat
 javy.wasm
 index.js

Makefile

@@ -2,19 +2,21 @@
 .DEFAULT_GOAL := cli
 
 cli: core
-		cd crates/cli && cargo build --release
+		cd crates/cli && cargo build && cd -
 
 check-benchmarks:
-	cd crates/benchmarks \
-		&& cargo check --benches --release
+		cd crates/benchmarks \
+				&& cargo check --benches --release \
+				&& cd -
 
 core:
 		cd crates/core \
-			&& cargo build --release --target=wasm32-wasi
+				&& cargo build --release --target=wasm32-wasi \
+				&& cd -
 
 test-core:
-	cd crates/core \
-		&& cargo wasi test --features standalone-wasi -- --nocapture
+		cd crates/core \
+				&& cargo wasi test --features standalone-wasi -- --nocapture
 
 tests: check-benchmarks test-core
 
@@ -24,13 +26,13 @@ fmt-quickjs-sys:
 		cd crates/quickjs-sys/ \
 				&& cargo fmt -- --check \
 				&& cargo clippy -- -D warnings \
-				&& cd - \
+				&& cd -
 
 fmt-core:
 		cd crates/core/ \
 				&& cargo fmt -- --check \
 				&& cargo clippy -- -D warnings \
-				&& cd - \
+				&& cd -
 
 fmt-cli:
 		cd crates/cli/ \

crates/cli/Cargo.toml

@@ -14,3 +14,7 @@ which = "4.2"
 structopt = "0.3"
 anyhow = "1.0"
 tempfile = "3.2.0"
+
+[build-dependencies]
+which = "4.2"
+

crates/cli/build.rs

@@ -1,5 +1,9 @@
 use std::env;
-use std::path::PathBuf;
+use std::fs;
+use std::io;
+use std::io::Write;
+use std::path::{Path, PathBuf};
+use std::process::Command;
 
 fn main() {
     copy_prebuilt_binaries();
@@ -14,56 +18,20 @@ fn main() {
 // When using clippy, we need to write a stubbed engine.wasm file to ensure compilation succeeds. This
 // skips building the actual engine.wasm binary that would be injected into the CLI binary.
 fn stub_engine_for_clippy() {
-    let out_dir: PathBuf = env::var("OUT_DIR")
-        .expect("failed to retrieve out dir")
-        .into();
+    let engine_path = PathBuf::from(env::var("OUT_DIR").unwrap()).join("engine.wasm");
 
-    let engine_path = out_dir.join("engine.wasm");
     if !engine_path.exists() {
-        std::fs::write(engine_path, "").expect("failed to write empty engine.wasm stub");
+        std::fs::write(engine_path, &[]).expect("failed to write empty engine.wasm stub");
         println!("cargo:warning=using stubbed engine.wasm for static analysis purposes...");
     }
 }
 
-fn copy_engine_binary() {
-    let profile = env::var("PROFILE").expect("Couldn't retrieve profile");
-    if profile != "release" {
-        eprintln!("only --release is supported due to https://github.com/bytecodealliance/wizer/issues/27");
-        std::process::exit(1);
-    }
-
-    let out_dir: PathBuf = env::var("OUT_DIR")
-        .expect("failed to retrieve out dir")
-        .into();
-
-    let engine_path: PathBuf = std::env::var("CARGO_MANIFEST_DIR")
-        .map(PathBuf::from)
-        .ok()
-        .map(|mut b| {
-            b.pop();
-            b.pop();
-            b.join("target")
-                .join("wasm32-wasi")
-                .join(profile)
-                .join("javy_core.wasm")
-        })
-        .expect("failed to create path");
-
-    println!("cargo:rerun-if-changed={:?}", engine_path);
-
-    // Only copy the file when it exists. Cargo will take care of re-running this script when the file changes.
-    if engine_path.exists() {
-        std::fs::copy(&engine_path, out_dir.join("engine.wasm"))
-            .unwrap_or_else(|_| panic!("failed to copy engine from {:?}", engine_path));
-    }
-}
-
 // Copy OS specific pre-built binaries to a known location. The binaries will be embedded in the final binary and
 // extracted to a temporary location if it's not already installed.
 fn copy_prebuilt_binaries() {
-    let target_dir = PathBuf::from(std::env::var("OUT_DIR").unwrap());
-    let target_os = PathBuf::from(std::env::var("CARGO_CFG_TARGET_OS").unwrap());
-    let root = PathBuf::from(std::env::var("CARGO_MANIFEST_DIR").unwrap());
+    let target_dir = PathBuf::from(env::var("OUT_DIR").unwrap());
+    let target_os = PathBuf::from(env::var("CARGO_CFG_TARGET_OS").unwrap());
+    let root = PathBuf::from(env::var("CARGO_MANIFEST_DIR").unwrap());
 
     let vendor_dir = root.join("vendor").join(target_os);
     let target_vendor_dir = target_dir.join("vendor");
@@ -79,3 +47,63 @@ fn copy_prebuilt_binaries() {
             }
         });
 }
+
+// Copy the engine binary build from the `core` crate, and run wasm-strip + wasm-opt against it as suggested by https://github.com/bytecodealliance/wizer/issues/27.
+fn copy_engine_binary() {
+    let mut engine_path = PathBuf::from(env::var("CARGO_MANIFEST_DIR").unwrap());
+    engine_path.pop();
+    engine_path.pop();
+    let engine_path = engine_path.join("target/wasm32-wasi/release/javy_core.wasm");
+
+    println!("cargo:rerun-if-changed={:?}", engine_path);
+
+    if engine_path.exists() {
+        let copied_engine_path = PathBuf::from(env::var("OUT_DIR").unwrap()).join("engine.wasm");
+
+        fs::copy(&engine_path, &copied_engine_path).unwrap();
+        optimize_engine(&copied_engine_path);
+    }
+}
+
+fn optimize_engine(engine_path: impl AsRef<Path>) {
+    if env::var("JAVY_SKIP_ENGINE_OPTIMIZATIONS").is_ok() {
+        return;
+    }
+
+    run_wasm_strip(&engine_path);
+    run_wasm_opt(&engine_path);
+}
+
+fn run_wasm_strip(engine_path: impl AsRef<Path>) {
+    let wasm_strip = which::which("wasm-strip")
+        .unwrap_or_else(|_| PathBuf::from(env::var("OUT_DIR").unwrap()).join("vendor/wasm-opt"));
+
+    let output = Command::new(wasm_strip)
+        .arg(engine_path.as_ref())
+        .output()
+        .unwrap();
+
+    println!("wasm-strip status: {}", output.status);
+    io::stdout().write_all(&output.stdout).unwrap();
+    io::stderr().write_all(&output.stderr).unwrap();
+    assert!(output.status.success());
+}
+
+fn run_wasm_opt(engine_path: impl AsRef<Path>) {
+    let wasm_opt = which::which("wasm-opt")
+        .unwrap_or_else(|_| PathBuf::from(env::var("OUT_DIR").unwrap()).join("vendor/wasm-opt"));
+
+    let output = Command::new(wasm_opt)
+        .arg(engine_path.as_ref())
+        .arg("-O3")
+        .arg("--dce")
+        .arg("-o")
+        .arg(engine_path.as_ref())
+        .output()
+        .unwrap();
+
+    println!("wasm-opt status: {}", output.status);
+    io::stdout().write_all(&output.stdout).unwrap();
+    io::stderr().write_all(&output.stderr).unwrap();
+    assert!(output.status.success());
+}