Channel.select: Complain if not passed an array.

lib/index.js

@@ -331,12 +331,12 @@ Channel.from = values => {
 };
 
 Channel.of = (...values) => Channel.from(values);
-
 Channel.isChannel = arg => prototype.isPrototypeOf(arg);
 
 Channel.select = methodPromises =>
   Object.assign(
     new Promise((resolve, reject) => {
+      try {
         methodPromises.forEach(async promise => {
           try {
             promise.prethen(() => {
@@ -353,17 +353,20 @@ Channel.select = methodPromises =>
               await promise;
             } catch (exception) {
               reject(exception);
-                `Channel.select accepts only promises returned by push & shift.`
             }
 
             resolve(promise.channel);
           } catch (exception) {
             reject(
               new TypeError(
+                `Channel.select accepts only promises returned by push & shift.`
               )
             );
           }
         });
+      } catch (exception) {
+        reject(new TypeError(`Channel.select: Argument must be an array.`));
+      }
     }),
     {
       cancel: () => Promise.all(methodPromises.map(promise => promise.cancel()))

test/index.js

@@ -124,6 +124,12 @@ describe(`Channel`, function() {
       await Channel.select([Promise.resolve()]);
     }, new TypeError(`Channel.select accepts only promises returned by push & shift.`));
   });
+
+  it(`complains if not given an array`, function() {
+    assertRejects(async () => {
+      await Channel.select(Channel.of(0).shift(), Channel.of(1).shift());
+    }, new TypeError(`Channel.select: Argument must be an array.`));
+  });
 });
 
 describe(`functional interface`, async function() {