Merge pull request #411 from xtuc/fix-module-import-id

fix: module imports should not use type index as their function identifier

Author: ColinEberhardt

packages/wasm-edit/test/ast-sync.js

@@ -61,17 +61,19 @@ function removeNodesOfType(t) {
   };
 }
 
+function makeTypeNode() {
+  return t.typeInstruction(undefined, t.signature([], []));
+}
+
 function makeFuncNodes(i, params = [], results = [], body = []) {
   body.push(t.instruction("nop"));
 
-  const id = t.identifier(getUniqueName("func"));
+  const id = t.identifier(`func_${i}`);
   const func = t.func(id, t.signature(params, results), body);
 
-  const functype = t.typeInstruction(undefined, t.signature(params, results));
-
   const funcindex = t.indexInFuncSection(i);
 
-  return [func, functype, funcindex];
+  return [func, funcindex];
 }
 
 function makeFuncExportNode(i) {
@@ -127,16 +129,17 @@ describe("AST synchronization", () => {
     b => addWithAST(ast, b, [makeGlobalNode(10)]),
     b => editWithAST(ast, b, removeNodesOfType("TypeInstruction")),
 
-    b => addWithAST(ast, b, makeFuncNodes(0)),
+    b => addWithAST(ast, b, [makeTypeNode()]),
+
+    b => addWithAST(ast, b, [makeFuncImportNode()]),
+    b => editWithAST(ast, b, renameImports("c")),
+
+    b => addWithAST(ast, b, makeFuncNodes(1)),
     b => addWithAST(ast, b, [makeFuncExportNode(0)]),
 
     b => addWithAST(ast, b, [makeGlobalImportNode()]),
     b => editWithAST(ast, b, renameImports("a")),
-    b => editWithAST(ast, b, renameImports("b")),
-
-    b => addWithAST(ast, b, [makeFuncImportNode()]),
-
-    b => editWithAST(ast, b, renameImports("c"))
+    b => editWithAST(ast, b, renameImports("b"))
   ];
 
   it("should run steps", function() {

packages/wasm-parser/src/decoder.js

@@ -450,7 +450,7 @@ export function decode(ab: ArrayBuffer, opts: DecoderOpts): Program {
           throw new CompileError(`function signature not found (${typeindex})`);
         }
 
-        const id = t.numberLiteralFromRaw(typeindex);
+        const id = getUniqueName("func");
 
         importDescr = t.funcImportDescr(
           id,

packages/wasm-parser/src/index.js

@@ -59,8 +59,8 @@ function restoreFunctionNames(ast) {
     ModuleImport({ node }: NodePath<ModuleImport>) {
       if (node.descr.type === "FuncImportDescr") {
         // $FlowIgnore
-        const nodeName: NumberLiteral = node.descr.id;
-        const index = nodeName.value;
+        const indexBasedFunctionName: string = node.descr.id;
+        const index = Number(indexBasedFunctionName.replace("func_", ""));
         const functionName = functionNames.find(f => f.index === index);
 
         if (functionName) {

packages/wasm-parser/test/fixtures/import/actual.wat renamed to packages/wasm-parser/test/fixtures/import/basic/actual.wat

@@ -0,0 +1,5 @@
+(module
+  (type (func (result i32)))
+  (type (func (param i32) (result i32)))
+  (import "a" "c" (func $fff (param i32) (result i32)))
+)

packages/wasm-parser/test/fixtures/import/complex/actual.wat

@@ -405,8 +405,6 @@ export function parse(tokensList: Array<Object>, source: string): Program {
       }
 
       const name = token.value;
-
-      let fnName = t.identifier(`${moduleName}.${name}`);
       eatToken();
 
       eatTokenOfType(tokens.openParen);
@@ -419,6 +417,8 @@ export function parse(tokensList: Array<Object>, source: string): Program {
         const fnParams = [];
         const fnResult = [];
 
+        let fnName = t.identifier(getUniqueName("func"));
+
         if (token.type === tokens.identifier) {
           fnName = identifierFromToken(token);
           eatToken();