Merge pull request #7531 from mrh-is/pod-update-doc

Document format of POD_NAMES in pod update

CHANGELOG.md

@@ -58,6 +58,9 @@ To install release candidates run `[sudo] gem install cocoapods --pre`
   [Samuel Giddins](https://github.com/segiddins)
   [#6899](https://github.com/CocoaPods/CocoaPods/issues/6899)
 
+* Document format of POD_NAMES in pod update  
+  [mrh-is](https://github.com/mrh-is)
+  
 ##### Bug Fixes
 
 * Prevent `xcassets` compilation from stomping over the apps `xcassets`  

lib/cocoapods/command/update.rb

@@ -8,11 +8,11 @@ module Pod
         'Podfile.lock'
 
       self.description = <<-DESC
-        Updates the Pods identified by the specified `POD_NAMES`. If no
-        `POD_NAMES` are specified it updates all the Pods ignoring the contents
-        of the Podfile.lock.
-        This command is reserved to the update of dependencies and pod install
-        should be used to install changes to the Podfile.
+        Updates the Pods identified by the specified `POD_NAMES`, which is a
+        space-delimited list of pod names. If no `POD_NAMES` are specified, it
+        updates all the Pods, ignoring the contents of the Podfile.lock. This
+        command is reserved for the update of dependencies; pod install should
+        be used to install changes to the Podfile.
       DESC
 
       self.arguments = [