bindings: a C ABI and an npm package alongside the wheel

crates/bindings/npm/build.sh

@@ -0,0 +1,52 @@
+#!/bin/sh
+# Build the npm package: one wasm module per target, and a package.json that
+# points at both.
+#
+# Two builds because the loaders differ. The node build reads the .wasm off
+# disk at import; the web build takes it as a URL a bundler rewrites. One
+# build serving both means a conditional import that every bundler gets wrong
+# in a different way.
+set -eu
+
+cd "$(dirname "$0")"
+crate=..
+out="$(pwd)/dist"
+
+command -v wasm-pack >/dev/null 2>&1 || {
+	echo "npm/build.sh: wasm-pack is not on PATH" >&2
+	exit 69
+}
+
+version=$(grep -m1 '^version' "$crate/../../Cargo.toml" | sed 's/.*"\(.*\)".*/\1/')
+
+rm -rf "$out"
+mkdir -p "$out"
+
+for target in nodejs web; do
+	case "$target" in
+	nodejs) dir=node ;;
+	*) dir=web ;;
+	esac
+	wasm-pack build "$crate" \
+		--target "$target" \
+		--out-dir "$out/$dir" \
+		--out-name catena \
+		--release \
+		-- --features wasm --no-default-features
+	# wasm-pack writes one of these per target and they disagree; the
+	# package.json below is the one that ships.
+	rm -f "$out/$dir/package.json" "$out/$dir/README.md" "$out/$dir/.gitignore"
+done
+
+# The node build is CommonJS and the package declares itself ESM, so the entry
+# has to say so in its extension or node reads `exports.x = …` as a syntax
+# error. The web build is already ESM and keeps its .js.
+mv "$out/node/catena.js" "$out/node/catena.cjs"
+mv "$out/node/catena.d.ts" "$out/node/catena.d.cts"
+
+sed "s/@VERSION@/$version/" package.json.in >"$out/package.json"
+cp README.md "$out/README.md"
+cp ../LICENSE "$out/LICENSE"
+
+echo "built $out (version $version)"
+echo "publish with: npm publish $out --access public"