Merge branch 'release/v0.1.3'

Author: tcrouch

shard.yml

@@ -1,5 +1,5 @@
 name: multiset
-version: 0.1.2
+version: 0.1.3
 
 authors:
   - Tom Crouch <tom.crouch@gmail.com>

spec/multiset_spec.cr

@@ -356,7 +356,17 @@ describe "Multiset" do
 
   describe "#each" do
     context "with no block given" do
-      it "iterates over unique elements" do
+      context "with no values" do
+        it "returns Stop" do
+          iter = Multiset.new(Array(Int32).new).each
+          iter.next.should be_a(Iterator::Stop)
+          iter.next.should be_a(Iterator::Stop)
+          iter.rewind
+          iter.next.should be_a(Iterator::Stop)
+        end
+      end
+
+      it "iterates over unique elements of one type" do
         iter = Multiset{1, 2, 3}.each
         iter.next.should eq(1)
         iter.next.should eq(2)
@@ -367,6 +377,17 @@ describe "Multiset" do
         iter.next.should eq(1)
       end
 
+      it "iterates over unique elements of union type" do
+        iter = Multiset{1, "a", 3}.each
+        iter.next.should eq(1)
+        iter.next.should eq("a")
+        iter.next.should eq(3)
+        iter.next.should be_a(Iterator::Stop)
+
+        iter.rewind
+        iter.next.should eq(1)
+      end
+
       it "iterates over duplicate elements" do
         iter = Multiset{1, 2, 3, 2, 1, 1}.each
         iter.next.should eq(1)
@@ -383,11 +404,18 @@ describe "Multiset" do
     end
 
     context "with block" do
-      it "yields each element" do
-        ms = Multiset{1, 2, 2, 3}
+      it "yields each over unique elements" do
+        ms = Multiset{1, 2, 3}
+        elems = [] of Int32
+        ms.each { |e| elems << e }
+        elems.should eq [1, 2, 3]
+      end
+
+      it "yields each over duplicate elements" do
+        ms = Multiset{1, 2, 3, 2, 1, 1}
         elems = [] of Int32
         ms.each { |e| elems << e }
-        elems.should eq [1, 2, 2, 3]
+        elems.should eq [1, 1, 1, 2, 2, 3]
       end
     end
   end

src/multiset.cr

@@ -18,7 +18,7 @@ struct Multiset(T)
   include Enumerable(T)
   include Iterable
 
-  VERSION = "0.1.2"
+  VERSION = "0.1.3"
 
   # creates a new empty multiset
   #
@@ -92,7 +92,7 @@ struct Multiset(T)
 
   # returns an iterator over each element
   def each
-    MultiEntryIterator(T).new(@hash, @hash.@first)
+    MultiEntryIterator(typeof(@hash.each), T).new(@hash.each)
   end
 
   # increments multiplicity of the given `Object` by `count` and returns self
@@ -449,33 +449,38 @@ struct Multiset(T)
   end
 
   # :nodoc:
-  class MultiEntryIterator(T)
+  private class MultiEntryIterator(I, T)
     include Iterator(T)
 
-    @h : Hash(T, Int32)
-    @current : Hash::Entry(T, Int32)?
+    @val : T | Stop
+    @count : Int32
 
-    def initialize(@h, @current)
-      @remaining = @current.try(&.value) || 0
+    def initialize(@iterator : I)
+      @val, @count = next_tuple
     end
 
     def next
-      if current = @current
-        value = current.key
-        if (@remaining -= 1) <= 0
-          @current = current.fore
-          @remaining = @current.try(&.value) || 0
-        end
-        value
-      else
-        stop
+      value = @val
+      return value if value.is_a?(Stop)
+
+      if (@count -= 1) <= 0
+        @val, @count = next_tuple
       end
+      value
     end
 
     def rewind
-      @current = @h.@first
-      @remaining = @current.try(&.value) || 0
+      @iterator.rewind
+      @val, @count = next_tuple
       self
     end
+
+    protected def next_tuple : Tuple(T | Stop, Int32)
+      if (value = @iterator.next).is_a?(Stop)
+        {Iterator.stop, 0}
+      else
+        value
+      end
+    end
   end
 end