Merge pull request #1859 from endojs/mfig-unbreak-callWhen

fix(exo): update `M.callWhen` broken by `M.raw()`
endojs · Nov 10, 2023 · 3dbeff7 · 3dbeff7
2 parents e4d9de9 + 015696d
commit 3dbeff7
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Showing 2 changed files with 45 additions and 8 deletions.
diff --git a/packages/exo/src/exo-tools.js b/packages/exo/src/exo-tools.js
@@ -182,6 +182,9 @@ const defendSyncMethod = (method, methodGuardPayload, label) => {
   return syncMethod;
 };
 
+/**
+ * @param {MethodGuardPayload} methodGuardPayload
+ */
 const desync = methodGuardPayload => {
   const {
     argGuards,
@@ -210,22 +213,43 @@ const desync = methodGuardPayload => {
   };
 };
 
+/**
+ * @param {(...args: unknown[]) => any} method
+ * @param {MethodGuardPayload} methodGuardPayload
+ * @param {string} label
+ */
 const defendAsyncMethod = (method, methodGuardPayload, label) => {
   const { returnGuard } = methodGuardPayload;
+  const isRawReturn = isRawGuard(returnGuard);
+
   const { awaitIndexes, rawMethodGuardPayload } = desync(methodGuardPayload);
+  const matchConfig = buildMatchConfig(rawMethodGuardPayload);
+
   const { asyncMethod } = {
     // Note purposeful use of `this` and concise method syntax
     asyncMethod(...args) {
-      const awaitList = awaitIndexes.map(i => args[i]);
+      const awaitList = [];
+      for (const i of awaitIndexes) {
+        if (i >= args.length) {
+          break;
+        }
+        awaitList.push(args[i]);
+      }
       const p = Promise.all(awaitList);
       const syncArgs = [...args];
-      const resultP = E.when(p, awaitedArgs => {
-        for (let j = 0; j < awaitIndexes.length; j += 1) {
-          syncArgs[awaitIndexes[j]] = awaitedArgs[j];
-        }
-        const realArgs = defendSyncArgs(syncArgs, rawMethodGuardPayload, label);
-        return apply(method, this, realArgs);
-      });
+      const resultP = E.when(
+        p,
+        /** @param {any[]} awaitedArgs */ awaitedArgs => {
+          for (let j = 0; j < awaitedArgs.length; j += 1) {
+            syncArgs[awaitIndexes[j]] = awaitedArgs[j];
+          }
+          const realArgs = defendSyncArgs(syncArgs, matchConfig, label);
+          return apply(method, this, realArgs);
+        },
+      );
+      if (isRawReturn) {
+        return resultP;
+      }
       return E.when(resultP, result => {
         mustMatch(harden(result), returnGuard, `${label}: result`);
         return result;

diff --git a/packages/exo/test/test-heap-classes.js b/packages/exo/test/test-heap-classes.js
@@ -24,6 +24,19 @@ test('what happens with extra arguments', t => {
   exo.foo('an extra arg');
 });
 
+const OptionalArrayI = M.interface('OptionalArray', {
+  foo: M.callWhen().optional(M.arrayOf(M.any())).returns(),
+});
+
+test('callWhen-guarded method called without optional array argument', async t => {
+  const exo = makeExo('WithNoOption', OptionalArrayI, {
+    async foo(arr) {
+      t.is(arr, undefined);
+    },
+  });
+  await t.notThrowsAsync(() => exo.foo());
+});
+
 const UpCounterI = M.interface('UpCounter', {
   incr: M.call()
     // TODO M.number() should not be needed to get a better error message