Handle nested array types

Author: surma

lib/asbind-instance/bind-function.js

@@ -9,7 +9,13 @@ function getFunctionFromKeyPath(baseObject, keys) {
 // Converts web platform names for the different ArrayBufferViews
 // to the names that ASC understands. Currently, that only means
 // to cut off the `Big` in `BigInt64Array`.
+const stdlibTypedArrayPrefix = "~lib/typedarray/";
 function normalizeArrayBufferViewTypeName(typeName) {
+  // Don’t do anything if this is not a stdlib type.
+  if (!typeName.startsWith(stdlibTypedArrayPrefix)) {
+    return typeName;
+  }
+  typeName = typeName.slice(stdlibTypedArrayPrefix.length);
   if (typeName.startsWith("Big")) {
     // Slice off `Big` as the loader doesn’t have that prefix.
     typeName = typeName.slice(3);
@@ -21,7 +27,7 @@ function getTypeId(asbindInstance, typeName) {
   if (typeName in asbindInstance.typeDescriptor.typeIds) {
     return asbindInstance.typeDescriptor.typeIds[typeName];
   }
-  throw Error(`Unknown type ${JSON.stringifty(typeName)}`);
+  throw Error(`Unknown type ${JSON.stringify(typeName)}`);
 }
 
 function nop(asbindInstance, value, typeName) {
@@ -49,11 +55,13 @@ function putArrayBuffer(asbindInstance, value, typeName) {
   );
 }
 
+const stdlibArray = "~lib/array/Array";
 function arrayInnerType(typeName) {
-  if (!typeName.startsWith("Array<")) {
+  if (!typeName.startsWith(stdlibArray)) {
     throw Error(`${JSON.stringify(typeName)} is not an array type`);
   }
-  return typeName.slice("Array<".length, -1);
+  // Cut off stdlib path + generic angle brackets.
+  return typeName.slice(`${stdlibArray}<`.length, -1);
 }
 
 function getArray(asbindInstance, value, typeName) {
@@ -81,24 +89,24 @@ const converters = new Map([
   [/^void$/, { ascToJs: nop, jsToAsc: nop }],
   [/^(i|u)(8|16|32)$/, { ascToJs: nop, jsToAsc: nop }],
   [/^f(32|64)$/, { ascToJs: nop, jsToAsc: nop }],
-  [/^[sS]tring$/, { ascToJs: getString, jsToAsc: putString }],
+  [/^~lib\/string\/String$/, { ascToJs: getString, jsToAsc: putString }],
   [
-    /^(Ui|I)nt(8|16|32)Array$/,
+    /^~lib\/typedarray\/(Ui|I)nt(8|16|32)Array$/,
     { ascToJs: getArrayBufferView, jsToAsc: putArrayBuffer }
   ],
   [
-    /^Big(Ui|I)nt64Array$/,
+    /^~lib\/typedarray\/Big(Ui|I)nt64Array$/,
     { ascToJs: getArrayBufferView, jsToAsc: putArrayBuffer }
   ],
   [
-    /^Uint8ClampedArray$/,
+    /^~lib\/typedarray\/Uint8ClampedArray$/,
     { ascToJs: getArrayBufferView, jsToAsc: putArrayBuffer }
   ],
   [
-    /^Float(32|64)Array$/,
+    /^~lib\/typedarray\/Float(32|64)Array$/,
     { ascToJs: getArrayBufferView, jsToAsc: putArrayBuffer }
   ],
-  [/^Array<.+>$/, { ascToJs: getArray, jsToAsc: putArray }]
+  [/^~lib\/array\/Array<.+>$/, { ascToJs: getArray, jsToAsc: putArray }]
 ]);
 
 const warned = new Set();

test/tests/array/asc.ts

@@ -6,3 +6,13 @@ export function swapAndPad(a: Array<f64>, b: f64[]): Array<f64> {
 }
 
 declare function swappedConcat(a: f64[], b: Array<f64>): f64[];
+
+export function join(s: Array<Array<string>>): string {
+  let result: string = "";
+  for (let outer = 0; outer < s.length; outer++) {
+    for (let inner = 0; inner < s[outer].length; inner++) {
+      result += s[outer][inner];
+    }
+  }
+  return result;
+}

test/tests/array/test.js

@@ -12,4 +12,16 @@ describe("as-bind", function() {
         [255, 10, 11, 12, 1, 2, 3, 255].join(",")
     );
   });
+
+  it("should handle nested array", async function() {
+    const instance = await AsBind.instantiate(this.rawModule, {
+      asc: {
+        swappedConcat(a, b) {
+          return [].concat(b, a);
+        }
+      }
+    });
+    const data = [["a", "b", "c"], ["1"], ["w", "x", "y", "z"]];
+    assert(instance.exports.join(data) === data.map(s => s.join("")).join(""));
+  });
 });

transform.js

@@ -11,11 +11,7 @@ function elementHasFlag(el, flag) {
 }
 
 function typeName(type) {
-  let name = type.name.text ?? type.name.identifier.text;
-  if (type.typeArguments.length > 0) {
-    name = `${name}<${type.typeArguments.map(typeName).join(",")}>`;
-  }
-  return name;
+  return type.getClass()?.internalName ?? type.toString();
 }
 
 function containingModule(func) {
@@ -29,26 +25,34 @@ function containingModule(func) {
 
 function getFunctionTypeDescriptor(func) {
   return {
-    returnType: typeName(func.declaration.signature.returnType),
-    parameters: func.declaration.signature.parameters.map(parameter =>
-      typeName(parameter.type)
+    returnType: typeName(func.signature.returnType),
+    parameters: func.signature.parameterTypes.map(parameter =>
+      typeName(parameter)
     )
   };
 }
 
-function extractTypeMap(func) {
-  // TODO: Generics?
-  func = func.instances.get("");
-  const result = {
-    [typeName(
-      func.declaration.signature.returnType
-    )]: func.signature.returnType?.getClass?.()?.id
-  };
-  func.declaration.signature.parameters.forEach((parameter, i) => {
-    result[typeName(parameter.type)] = func.signature.parameterTypes[
-      i
-    ].getClass?.()?.id;
-  });
+function extractTypeIds(type) {
+  const result = {};
+  const clazz = type.getClass?.();
+  if (!clazz) {
+    return result;
+  }
+  result[clazz.internalName] = clazz.id;
+  if (clazz.typeArguments) {
+    for (const subType of clazz.typeArguments) {
+      Object.assign(result, extractTypeIds(subType));
+    }
+  }
+  return result;
+}
+
+function extractTypeIdsFromFunction(func) {
+  const result = {};
+  Object.assign(result, extractTypeIds(func.signature.returnType));
+  func.signature.parameterTypes.forEach(paramType =>
+    Object.assign(result, extractTypeIds(paramType))
+  );
   return result;
 }
 
@@ -78,7 +82,14 @@ class AsBindTransform extends Transform {
 
     const typeIds = {};
     const importedFunctions = {};
-    for (const importedFunction of flatImportedFunctions) {
+    for (let importedFunction of flatImportedFunctions) {
+      if (
+        importedFunction.instances.size > 1 ||
+        !importedFunction.instances.has("")
+      ) {
+        throw Error(`Can’t import or export generic functions.`);
+      }
+      importedFunction = importedFunction.instances.get("");
       // To know under what module name an imported function will be expected,
       // we have to find the containing module of the given function, take the
       // internal name (which is effectively the file path without extension)
@@ -93,14 +104,21 @@ class AsBindTransform extends Transform {
       importedFunctions[moduleName][
         importedFunction.name
       ] = getFunctionTypeDescriptor(importedFunction);
-      Object.assign(typeIds, extractTypeMap(importedFunction));
+      Object.assign(typeIds, extractTypeIdsFromFunction(importedFunction));
     }
     const exportedFunctions = {};
-    for (const exportedFunction of flatExportedFunctions) {
+    for (let exportedFunction of flatExportedFunctions) {
+      if (
+        exportedFunction.instances.size > 1 ||
+        !exportedFunction.instances.has("")
+      ) {
+        throw Error(`Can’t import or export generic functions.`);
+      }
+      exportedFunction = exportedFunction.instances.get("");
       exportedFunctions[exportedFunction.name] = getFunctionTypeDescriptor(
         exportedFunction
       );
-      Object.assign(typeIds, extractTypeMap(exportedFunction));
+      Object.assign(typeIds, extractTypeIdsFromFunction(exportedFunction));
     }
     this.typeData = JSON.stringify({
       typeIds,