Fixup TypeScript with export maps (#1284)

Summary:
Pull Request resolved: https://github.com/facebook/yoga/pull/1284

This makes TypeScript resolution play nicely with export maps, and converts the entrypoints to TypeScript.

We remove the non-export-map fallbacks as well, so the export maps are always followed.

Tests are moved to load yoga from its external export, testing the entrypoints.

This moves the only untyped bit to the binary wrapper, which another diff will move.

Reviewed By: yungsters

Differential Revision: D45713689

fbshipit-source-id: 228e6f2c9d53520230707a81e76c3c35fcd46de5

javascript/src/wrapAssembly.js

@@ -0,0 +1,146 @@
+/**
+ * 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
+ */
+
+import YGEnums, {Unit, Direction} from './generated/YGEnums';
+
+module.exports = lib => {
+  function patch(prototype, name, fn) {
+    const original = prototype[name];
+
+    prototype[name] = function (...args) {
+      return fn.call(this, original, ...args);
+    };
+  }
+
+  for (const fnName of [
+    'setPosition',
+    'setMargin',
+    'setFlexBasis',
+    'setWidth',
+    'setHeight',
+    'setMinWidth',
+    'setMinHeight',
+    'setMaxWidth',
+    'setMaxHeight',
+    'setPadding',
+  ]) {
+    const methods = {
+      [Unit.Point]: lib.Node.prototype[fnName],
+      [Unit.Percent]: lib.Node.prototype[`${fnName}Percent`],
+      [Unit.Auto]: lib.Node.prototype[`${fnName}Auto`],
+    };
+
+    patch(lib.Node.prototype, fnName, function (original, ...args) {
+      // We patch all these functions to add support for the following calls:
+      // .setWidth(100) / .setWidth("100%") / .setWidth(.getWidth()) / .setWidth("auto")
+
+      const value = args.pop();
+      let unit, asNumber;
+
+      if (value === 'auto') {
+        unit = Unit.Auto;
+        asNumber = undefined;
+      } else if (typeof value === 'object') {
+        unit = value.unit;
+        asNumber = value.valueOf();
+      } else {
+        unit =
+          typeof value === 'string' && value.endsWith('%')
+            ? Unit.Percent
+            : Unit.Point;
+        asNumber = parseFloat(value);
+        if (!Number.isNaN(value) && Number.isNaN(asNumber)) {
+          throw new Error(`Invalid value ${value} for ${fnName}`);
+        }
+      }
+
+      if (!methods[unit])
+        throw new Error(
+          `Failed to execute "${fnName}": Unsupported unit '${value}'`,
+        );
+
+      if (asNumber !== undefined) {
+        return methods[unit].call(this, ...args, asNumber);
+      } else {
+        return methods[unit].call(this, ...args);
+      }
+    });
+  }
+
+  function wrapMeasureFunction(measureFunction) {
+    return lib.MeasureCallback.implement({
+      measure: (...args) => {
+        const {width, height} = measureFunction(...args);
+        return {
+          width: width ?? NaN,
+          height: height ?? NaN,
+        };
+      },
+    });
+  }
+
+  patch(lib.Node.prototype, 'setMeasureFunc', function (original, measureFunc) {
+    // This patch is just a convenience patch, since it helps write more
+    // idiomatic source code (such as .setMeasureFunc(null))
+    if (measureFunc) {
+      return original.call(this, wrapMeasureFunction(measureFunc));
+    } else {
+      return this.unsetMeasureFunc();
+    }
+  });
+
+  function wrapDirtiedFunc(dirtiedFunction) {
+    return lib.DirtiedCallback.implement({dirtied: dirtiedFunction});
+  }
+
+  patch(lib.Node.prototype, 'setDirtiedFunc', function (original, dirtiedFunc) {
+    original.call(this, wrapDirtiedFunc(dirtiedFunc));
+  });
+
+  patch(lib.Config.prototype, 'free', function () {
+    // Since we handle the memory allocation ourselves (via lib.Config.create),
+    // we also need to handle the deallocation
+    lib.Config.destroy(this);
+  });
+
+  patch(lib.Node, 'create', (_, config) => {
+    // We decide the constructor we want to call depending on the parameters
+    return config
+      ? lib.Node.createWithConfig(config)
+      : lib.Node.createDefault();
+  });
+
+  patch(lib.Node.prototype, 'free', function () {
+    // Since we handle the memory allocation ourselves (via lib.Node.create),
+    // we also need to handle the deallocation
+    lib.Node.destroy(this);
+  });
+
+  patch(lib.Node.prototype, 'freeRecursive', function () {
+    for (let t = 0, T = this.getChildCount(); t < T; ++t) {
+      this.getChild(0).freeRecursive();
+    }
+    this.free();
+  });
+
+  patch(
+    lib.Node.prototype,
+    'calculateLayout',
+    function (original, width = NaN, height = NaN, direction = Direction.LTR) {
+      // Just a small patch to add support for the function default parameters
+      return original.call(this, width, height, direction);
+    },
+  );
+
+  return {
+    Config: lib.Config,
+    Node: lib.Node,
+    ...YGEnums,
+  };
+};