Make Enumerable#first compliant

opal · Nov 11, 2013 · 337e9bc · 337e9bc
1 parent c2e533b
commit 337e9bc
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Showing 2 changed files with 26 additions and 19 deletions.
diff --git a/opal/core/enumerable.rb b/opal/core/enumerable.rb
@@ -468,35 +468,47 @@ def find_index(object = undefined, &block)
   end
 
   def first(number = undefined)
-    %x{
-      if (number == null) {
-        var result = nil;
+    if `number === undefined`
+      result = nil
 
+      %x{
         self.$each._p = function() {
           result = #{Opal.destructure(`arguments`)};
+
           return $breaker;
         };
+
+        self.$each();
       }
-      else {
+    else
+      result = []
+      number = Opal.coerce_to number, Integer, :to_int
+
+      if `number < 0`
+        raise ArgumentError, 'attempt to take negative size'
+      end
+
+      if `number == 0`
+        return []
+      end
+
+      %x{
         var current = 0,
-            result  = [],
             number  = #{Opal.coerce_to number, Integer, :to_int};
 
         self.$each._p = function() {
-          if (number <= current) {
-            return $breaker;
-          }
-
           result.push(#{Opal.destructure(`arguments`)});
 
-          current++;
+          if (number <= ++current) {
+            return $breaker;
+          }
         };
-      }
 
-      self.$each();
+        self.$each();
+      }
+    end
 
-      return result;
-    }
+    result
   end
 
   def grep(pattern, &block)

diff --git a/spec/filters/bugs/enumerable.rb b/spec/filters/bugs/enumerable.rb
@@ -1,11 +1,6 @@
 opal_filter "Enumerable" do
   fails "Enumerable#cycle passed a number n as an argument raises an ArgumentError if more arguments are passed"
 
-  fails "Enumerable#first when passed an argument consumes only what is needed"
-  fails "Enumerable#first when passed an argument raises a TypeError if the passed argument is not numeric"
-  fails "Enumerable#first when passed an argument tries to convert the passed argument to an Integer using #to_int"
-  fails "Enumerable#first when passed an argument raises an ArgumentError when count is negative"
-
   fails "Enumerable#grep can use $~ in the block when used with a Regexp"
 
   fails "Enumerable#group_by returns a hash without default_proc"