Revive JavaScript Bindings (#1177)

Summary:
Yoga's JavaScript bindings do not work past Node 10, or on recent versions of Ubuntu even using it. This is due to a reliance on `nbind`, a library which is no longer maintained. `nbind` itself abstracts over `embind` running Emscripten to generate an asm.js build, along with building Node native modules. In the meantime, [yoga-layout-prebuilt](https://www.npmjs.com/package/yoga-layout-prebuilt) has been used by the community instead of the official package.

https://github.com/facebook/yoga/pull/1177 was contributed as a conversion of bindings created using `nbind` to instead use `embind` directly.

I continued building on this to add more:
1. WebAssembly support (required to be async in browsers)
2. CMake + Ninja Build for the 4 flavors
3. TypeScript typings (partially generated)
4. yarn scripts to build (working on macOS, Ubuntu, Windows)
5. A README with some usage and contribution instructions
6. Updated tests to work with Jest, and updated general infra
7. ESLint and clang-format scripts
8. More GitHub actions (and now testing Windows)
9. Probably more I kinda got carried away here lol

The plan is to eventually publish this to NPM, but there is a little bit of work after this before that happens.

Pull Request resolved: https://github.com/facebook/yoga/pull/1177

Test Plan: The bindings pass Jest tests (both manual and generated). GitHub actions added for the different yarn scripts. Did some manual checks on using the library as TS.

Reviewed By: christophpurrer

Differential Revision: D42207782

Pulled By: NickGerleman

fbshipit-source-id: 1dc5ce440f1c2b9705a005bbdcc86f952785d94e

javascript/just.config.js

@@ -0,0 +1,143 @@
+/**
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ *
+ * @format
+ */
+
+const {
+  argv,
+  copyTask,
+  eslintTask,
+  logger,
+  jestTask,
+  option,
+  parallel,
+  series,
+  spawn,
+  task,
+} = require("just-scripts");
+
+const glob = require("glob");
+const which = require("which");
+
+const node = process.execPath;
+
+option("fix");
+
+task(
+  "prepare-for-build",
+  parallel(
+    babelTransformTask({ paths: ["src_js"], dest: "dist" }),
+    copyTask({ paths: ["src_js/**/*.d.ts"], dest: "dist" }),
+    emcmakeGenerateTask()
+  )
+);
+
+function defineFlavor(flavor, env) {
+  task(`cmake-build:${flavor}`, cmakeBuildTask([flavor]));
+  task(`jest:${flavor}`, jestTask({ env }));
+  task(
+    `test:${flavor}`,
+    series("prepare-for-build", `cmake-build:${flavor}`, `jest:${flavor}`)
+  );
+}
+
+defineFlavor("asmjs-async", { WASM: 0, SYNC: 0 });
+defineFlavor("asmjs-sync", { WASM: 0, SYNC: 1 });
+defineFlavor("wasm-async", { WASM: 1, SYNC: 0 });
+defineFlavor("wasm-sync", { WASM: 1, SYNC: 1 });
+
+task("cmake-build:all", cmakeBuildTask());
+task("cmake-build:async", cmakeBuildTask(["asmjs-async", "wasm-async"]));
+task("cmake-build:sync", cmakeBuildTask(["asmjs-sync", "wasm-sync"]));
+
+task("build", series("prepare-for-build", "cmake-build:all"));
+
+task(
+  "test",
+  series(
+    "prepare-for-build",
+    series("cmake-build:asmjs-async", "jest:asmjs-async"),
+    series("cmake-build:asmjs-sync", "jest:asmjs-sync"),
+    series("cmake-build:wasm-async", "jest:wasm-async"),
+    series("cmake-build:wasm-sync", "jest:wasm-sync")
+  )
+);
+
+task(
+  "benchmark",
+  series("prepare-for-build", "cmake-build:sync", runBenchTask())
+);
+
+task(
+  "lint",
+  series(eslintTask({ fix: argv().fix }), clangFormatTask({ fix: argv().fix }))
+);
+
+function babelTransformTask(opts) {
+  return () => {
+    const args = [...opts.paths, "--source-maps", "--out-dir", opts.dest];
+    logger.info(`Transforming [${opts.paths.join(",")}] to '${opts.dest}'`);
+
+    return spawn(node, [require.resolve("@babel/cli/bin/babel"), ...args]);
+  };
+}
+
+function runBenchTask() {
+  return () => {
+    const files = glob.sync("./tests/Benchmarks/**/*.js");
+    const args = ["./tests/run-bench.js", ...files];
+    logger.info(args.join(" "));
+
+    return spawn(node, args, { stdio: "inherit" });
+  };
+}
+
+function emcmakeGenerateTask() {
+  return () => {
+    const emcmake = which.sync("emcmake");
+    const ninja = which.sync("ninja", { nothrow: true });
+    const args = [
+      "cmake",
+      "-S",
+      ".",
+      "-B",
+      "build",
+      ...(ninja ? ["-G", "Ninja"] : []),
+    ];
+    logger.info(["encmake", ...args].join(" "));
+
+    return spawn(emcmake, args);
+  };
+}
+
+function cmakeBuildTask(targets) {
+  return () => {
+    const cmake = which.sync("cmake");
+    const args = [
+      "--build",
+      "build",
+      ...(targets ? ["--target", ...targets] : []),
+    ];
+    logger.info(["cmake", ...args].join(" "));
+
+    return spawn(cmake, args, { stdio: "inherit" });
+  };
+}
+
+function clangFormatTask(opts) {
+  return () => {
+    const args = [
+      ...(opts.fix ? ["-i"] : ["--dry-run", "--Werror"]),
+      ...glob.sync("**/*.{h,hh,hpp,c,cpp,cc,m,mm}"),
+    ];
+    logger.info(["clang-format", ...args].join(" "));
+
+    return spawn(node, [require.resolve("clang-format"), ...args], {
+      stdio: "inherit",
+    });
+  };
+}