adds test coverage for edge-cases of Array.wrap, and better documentation for how it differs from Kernel#Array

1 files changed, 8 insertions, 1 deletions

diff --git a/railties/guides/source/active_support_core_extensions.textile b/railties/guides/source/active_support_core_extensions.textile
index d14a531abe..fc59df9fe4 100644
--- a/railties/guides/source/active_support_core_extensions.textile
+++ b/railties/guides/source/active_support_core_extensions.textile
@@ -2229,7 +2229,14 @@ NOTE: Defined in +active_support/core_ext/array/conversions.rb+.
 
 h4. Wrapping
 
-The class method +Array.wrap+ behaves like the function +Array()+ except that it does not try to call +to_a+ on its argument. That changes the behavior for enumerables:
+The class method +Array.wrap+ behaves like the function +Array()+ except:
+
+* If the argument responds to +to_ary+ the method is invoked. <tt>Kernel#Array</tt> moves on to try +to_a+ if the returned value is +nil+, but <tt>Arraw.wrap</tt> returns such a +nil+ right away.
+* If the returned value from +to_ary+ is neither +nil+ nor an +Array+ object, <tt>Kernel#Array</tt> raises an exception, while <tt>Array.wrap</tt> does not, it just returns the value.
+* It does not call +to_a+ on the argument, though special-cases +nil+ to return an empty array.
+
+
+ that it does not try to call +to_a+ on its argument. That changes the behavior for enumerables:
 
 <ruby>
 Array.wrap(:foo => :bar) # => [{:foo => :bar}]