Pry::WrappedModule.from_str respects binding

* module are now looked up with respect to the optional binding parameter to from_str
* also improved some docs

lib/pry/default_commands/find_method.rb

@@ -18,8 +18,8 @@ module DefaultCommands
           Use the `-n` switch (the default) to search for methods whose name matches the given regex.
           Use the `-c` switch to search for methods that contain the given code.
 
-          e.g find re Pry                # find all methods whose name match /re/. Matches Pry#repl, etc.
-          e.g find -c 'output.puts' Pry  # find all methods that contain the code: output.puts
+          e.g find re Pry                # find all methods whose name match /re/ inside the Pry namespace. Matches Pry#repl, etc.
+          e.g find -c 'output.puts' Pry  # find all methods that contain the code: output.puts inside the Pry namepsace.
         BANNER
 
         def setup

lib/pry/default_commands/introspection.rb

@@ -67,7 +67,7 @@ def options(opt)
         end
 
         def process_module(name)
-          mod = Pry::WrappedModule.from_str(name)
+          mod = Pry::WrappedModule.from_str(name, target)
 
           if opts.present?(:all)
             all_modules(mod)
@@ -187,8 +187,8 @@ def process
         description "Show the source for METH or CLASS. Aliases: $, show-method"
 
         banner <<-BANNER
-          Usage: show-method [OPTIONS] [METH|CLASS]
-          Aliases: $, show-source
+          Usage: show-source [OPTIONS] [METH|CLASS]
+          Aliases: $, show-method
 
           Show the source for method METH or CLASS. Tries instance methods first and then methods by default.
 
@@ -227,7 +227,7 @@ def process_method
         end
 
         def process_module(name)
-          mod = Pry::WrappedModule.from_str(name)
+          mod = Pry::WrappedModule.from_str(name, target)
 
           if opts.present?(:all)
             all_modules(mod)

lib/pry/wrapped_module.rb

@@ -26,7 +26,12 @@ class WrappedModule
     # @example
     #   Pry::WrappedModule.from_str("Pry::Code")
     def self.from_str(mod_name, binding=TOPLEVEL_BINDING)
-      Pry::WrappedModule.new(binding.eval(mod_name))
+      mod = binding.eval(mod_name)
+      if mod.is_a?(Module)
+        Pry::WrappedModule.new(mod)
+      else
+        nil
+      end
     rescue RescuableException
       nil
     end