+split, Milestone 1

Author: akarnokd

gradle.properties

@@ -1 +1 @@
-version=1.0.0-M0
+version=1.0.0-M1

src/main/java/ix/Ix.java

@@ -182,6 +182,10 @@ public static <T, R> Ix<R> forloop(T seed, Pred<? super T> condition,
             Func1<? super T, ? extends R> selector) {
         return new IxForloop<T, R>(seed, condition, selector, next);
     }
+    
+    public static Ix<String> split(String string, String by) {
+        return new IxSplit(string, by);
+    }
 
     //---------------------------------------------------------------------------------------
     // Instance operators

src/main/java/ix/IxSplit.java

@@ -0,0 +1,51 @@
+package ix;
+
+import java.util.Iterator;
+
+final class IxSplit extends Ix<String> {
+
+    final String string;
+    
+    final String by;
+    
+    public IxSplit(String string, String by) {
+        this.string = string;
+        this.by = by;
+    }
+
+    @Override
+    public Iterator<String> iterator() {
+        return new SplitIterator(string, by);
+    }
+
+    static final class SplitIterator extends IxBaseIterator<String> {
+        final String string;
+        
+        final String by;
+
+        int index;
+
+        public SplitIterator(String string, String by) {
+            this.string = string;
+            this.by = by;
+        }
+        
+        @Override
+        protected boolean moveNext() {
+            int i = index;
+            int j = string.indexOf(by, i);
+            
+            if (j < 0) {
+                value = string.substring(i);
+                hasValue = true;
+                done = true;
+                return true;
+            }
+
+            hasValue = true;
+            index = j + by.length();
+            value = string.substring(i, j);
+            return true;
+        }
+    }
+}

src/test/java/ix/SplitTest.java

@@ -0,0 +1,67 @@
+/*
+ * Copyright 2011-2016 David Karnok
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package ix;
+
+import org.junit.Test;
+
+public class SplitTest {
+
+    @Test
+    public void normal() {
+        Ix<String> source = Ix.split("a|b|c|d", "|");
+        
+        IxTestHelper.assertValues(source, "a", "b", "c", "d");
+        
+        IxTestHelper.assertNoRemove(source);
+    }
+    
+    @Test
+    public void normal2() {
+        Ix<String> source = Ix.split("a|b|c|", "|");
+        
+        IxTestHelper.assertValues(source, "a", "b", "c", "");
+        
+        IxTestHelper.assertNoRemove(source);
+    }
+    
+    @Test
+    public void normal3() {
+        Ix<String> source = Ix.split("a1|b2|c3", "|");
+        
+        IxTestHelper.assertValues(source, "a1", "b2", "c3");
+        
+        IxTestHelper.assertNoRemove(source);
+    }
+    
+    @Test
+    public void normal4() {
+        Ix<String> source = Ix.split("a1|<b2|c3|<d4", "|<");
+        
+        IxTestHelper.assertValues(source, "a1", "b2|c3", "d4");
+        
+        IxTestHelper.assertNoRemove(source);
+    }
+    
+    @Test
+    public void empty() {
+        Ix<String> source = Ix.split("", "|");
+        
+        IxTestHelper.assertValues(source, "");
+        
+        IxTestHelper.assertNoRemove(source);
+    }
+}