opal · Feb 27, 2015 · Feb 27, 2015 · Feb 27, 2015 · Feb 27, 2015 · Feb 27, 2015
Showing with 52 additions and 9 deletions.

+2 −0 CHANGELOG.md

+50 −0 opal/corelib/array.rb

+0 −9 spec/filters/bugs/array.rb
diff --git a/CHANGELOG.md b/CHANGELOG.md
@@ -4,6 +4,8 @@
 
 *   `String#[]` and `String#slice` implementation fully compliant with rubyspec
 
+*   `Array#product` implementation fully compliant with rubyspec
+
 ## 0.7.1 2015-02-14
 
 *   CLI options `-d` and `-v` now set respectively `$DEBUG` and `$VERBOSE`

diff --git a/opal/corelib/array.rb b/opal/corelib/array.rb
@@ -1138,6 +1138,56 @@ def pop(count = undefined)
     end
   end
 
+  def product(*args, &block)
+    %x{
+      var result = #{block_given?} ? null : [],
+          n = args.length + 1,
+          counters = new Array(n),
+          lengths  = new Array(n),
+          arrays   = new Array(n),
+          i, m, subarray, len, resultlen = 1;
+
+      arrays[0] = self;
+      for (i = 1; i < n; i++) {
+        arrays[i] = #{Opal.coerce_to(`args[i - 1]`, Array, :to_ary)};
+      }
+
+      for (i = 0; i < n; i++) {
+        len = arrays[i].length;
+        if (len === 0) {
+          return result || self;
+        }
+        resultlen *= len;
+        if (resultlen > 2147483647) {
+          #{raise RangeError, "too big to product"}
+        }
+        lengths[i] = len;
+        counters[i] = 0;
+      }
+
+      outer_loop: for (;;) {
+        subarray = [];
+        for (i = 0; i < n; i++) {
+          subarray.push(arrays[i][counters[i]]);
+        }
+        if (result) {
+          result.push(subarray);
+        } else {
+          #{yield `subarray`}
+        }
+        m = n - 1;
+        counters[m]++;
+        while (counters[m] === lengths[m]) {
+          counters[m] = 0;
+          if (--m < 0) break outer_loop;
+          counters[m]++;
+        }
+      }
+
+      return result || self;
+    }
+  end
+
   def push(*objects)
     %x{
       for (var i = 0, length = objects.length; i < length; i++) {

diff --git a/spec/filters/bugs/array.rb b/spec/filters/bugs/array.rb
@@ -81,15 +81,6 @@
   fails "Array#permutation returns an Enumerator of permutations of given length when called with an argument but no block"
   fails "Array#permutation returns an Enumerator of all permutations when called without a block or arguments"
 
-  fails "Array#product when given an empty block returns self"
-  fails "Array#product when given a block will ignore unreasonable numbers of products and yield anyway"
-  fails "Array#product when given a block yields all combinations in turn"
-  fails "Array#product does not attempt to produce an unreasonable number of products"
-  fails "Array#product returns an empty array when the argument is an empty array"
-  fails "Array#product has no required argument"
-  fails "Array#product returns the expected result"
-  fails "Array#product returns converted arguments using :to_ary"
-
   fails "Array#rassoc does not check the last element in each contained but speficically the second"
   fails "Array#rassoc calls elem == obj on the second element of each contained array"