sendTypingIndicator: make callback optional (Schmavery#457)

Added warning when there is a `callback` but it is not a function.

DOCS.md

@@ -944,7 +944,7 @@ login({email: "EMAIL", password: "PASSWORD"}, (err, api) => {
 <a name="sendTypingIndicator"></a>
 ### api.sendTypingIndicator(threadID[, callback])
 
-Sends a "USERNAME is typing" indicator to other members of the thread indicated by threadID.  This indication will disappear after 30 second or when the `end` function is called. The `end` function is returned by `api.sendTypingIndicator`.
+Sends a "USERNAME is typing" indicator to other members of the thread indicated by `threadID`. This indication will disappear after 30 second or when the `end` function is called. The `end` function is returned by `api.sendTypingIndicator`.
 
 __Arguments__
 

src/sendTypingIndicator.js

@@ -12,7 +12,7 @@ module.exports = function(defaultFuncs, api, ctx) {
       thread: threadID
     };
 
-    // Check if thread is single person chat or group chat
+    // Check if thread is a single person chat or a group chat
     // More info on this is in api.sendMessage
     api.getUserInfo(threadID, function(err, res) {
       if (err) {
@@ -42,15 +42,24 @@ module.exports = function(defaultFuncs, api, ctx) {
   }
 
   return function sendTypingIndicator(threadID, callback) {
-    if(!callback) {
-      throw {error: "sendTypingIndicator: need callback"};
+    if (utils.getType(callback) !== 'Function' && utils.getType(callback) !== 'AsyncFunction') {
+      if (callback) {
+        log.warn("sendTypingIndicator", "callback is not a function - ignoring.");
+      }
+      callback = () => {};
     }
 
     makeTypingIndicator(true, threadID, callback);
 
-    // TODO: document that we return the stop/cancel functions now
     return function end(cb) {
-      makeTypingIndicator(false, threadID, cb || function() {***REMOVED***;
+      if (utils.getType(cb) !== 'Function' && utils.getType(cb) !== 'AsyncFunction') {
+        if (cb) {
+          log.warn("sendTypingIndicator", "callback is not a function - ignoring.");
+        }
+        cb = () => {};
+      }
+
+      makeTypingIndicator(false, threadID, cb);
     };
   };
 };