Add a few more tests

Explicitly test the case where the slice is oversized/undersized on the
left/right.

Author: wincent

src/connection/__tests__/arrayconnection.js

@@ -688,7 +688,67 @@ describe('connectionFromArraySlice()', () => {
     });
   });
 
-  it('works with an oversized array slice', () => {
+  it('works with an oversized array slice ("left" side)', () => {
+    var c = connectionFromArraySlice(
+      letters.slice(0, 3),
+      {
+        first: 2,
+        after: 'YXJyYXljb25uZWN0aW9uOjA=',
+      },
+      {
+        sliceStart: 0,
+        arrayLength: 5,
+      }
+    );
+    return expect(c).to.deep.equal({
+      edges: [
+        {
+          node: 'B',
+          cursor: 'YXJyYXljb25uZWN0aW9uOjE=',
+        },
+        {
+          node: 'C',
+          cursor: 'YXJyYXljb25uZWN0aW9uOjI=',
+        },
+      ],
+      pageInfo: {
+        startCursor: 'YXJyYXljb25uZWN0aW9uOjE=',
+        endCursor: 'YXJyYXljb25uZWN0aW9uOjI=',
+        hasPreviousPage: false,
+        hasNextPage: true,
+      }
+    });
+  });
+
+  it('works with an oversized array slice ("right" side)', () => {
+    var c = connectionFromArraySlice(
+      letters.slice(2, 4),
+      {
+        first: 1,
+        after: 'YXJyYXljb25uZWN0aW9uOjE=',
+      },
+      {
+        sliceStart: 2,
+        arrayLength: 5,
+      }
+    );
+    return expect(c).to.deep.equal({
+      edges: [
+        {
+          node: 'C',
+          cursor: 'YXJyYXljb25uZWN0aW9uOjI=',
+        },
+      ],
+      pageInfo: {
+        startCursor: 'YXJyYXljb25uZWN0aW9uOjI=',
+        endCursor: 'YXJyYXljb25uZWN0aW9uOjI=',
+        hasPreviousPage: false,
+        hasNextPage: true,
+      }
+    });
+  });
+
+  it('works with an oversized array slice (both sides)', () => {
     var c = connectionFromArraySlice(
       letters.slice(1, 4),
       {
@@ -716,9 +776,41 @@ describe('connectionFromArraySlice()', () => {
     });
   });
 
-  it('works with an undersized array slice', () => {
+  it('works with an undersized array slice ("left" side)', () => {
     var c = connectionFromArraySlice(
-      letters.slice(2, 3),
+      letters.slice(3, 5),
+      {
+        first: 3,
+        after: 'YXJyYXljb25uZWN0aW9uOjE=',
+      },
+      {
+        sliceStart: 3,
+        arrayLength: 5,
+      }
+    );
+    return expect(c).to.deep.equal({
+      edges: [
+        {
+          node: 'D',
+          cursor: 'YXJyYXljb25uZWN0aW9uOjM=',
+        },
+        {
+          node: 'E',
+          cursor: 'YXJyYXljb25uZWN0aW9uOjQ=',
+        },
+      ],
+      pageInfo: {
+        startCursor: 'YXJyYXljb25uZWN0aW9uOjM=',
+        endCursor: 'YXJyYXljb25uZWN0aW9uOjQ=',
+        hasPreviousPage: false,
+        hasNextPage: false,
+      }
+    });
+  });
+
+  it('works with an undersized array slice ("right" side)', () => {
+    var c = connectionFromArraySlice(
+      letters.slice(2, 4),
       {
         first: 3,
         after: 'YXJyYXljb25uZWN0aW9uOjE=',
@@ -734,10 +826,42 @@ describe('connectionFromArraySlice()', () => {
           node: 'C',
           cursor: 'YXJyYXljb25uZWN0aW9uOjI=',
         },
+        {
+          node: 'D',
+          cursor: 'YXJyYXljb25uZWN0aW9uOjM=',
+        },
       ],
       pageInfo: {
         startCursor: 'YXJyYXljb25uZWN0aW9uOjI=',
-        endCursor: 'YXJyYXljb25uZWN0aW9uOjI=',
+        endCursor: 'YXJyYXljb25uZWN0aW9uOjM=',
+        hasPreviousPage: false,
+        hasNextPage: true,
+      }
+    });
+  });
+
+  it('works with an undersized array slice (both sides)', () => {
+    var c = connectionFromArraySlice(
+      letters.slice(3, 4),
+      {
+        first: 3,
+        after: 'YXJyYXljb25uZWN0aW9uOjE=',
+      },
+      {
+        sliceStart: 3,
+        arrayLength: 5,
+      }
+    );
+    return expect(c).to.deep.equal({
+      edges: [
+        {
+          node: 'D',
+          cursor: 'YXJyYXljb25uZWN0aW9uOjM=',
+        },
+      ],
+      pageInfo: {
+        startCursor: 'YXJyYXljb25uZWN0aW9uOjM=',
+        endCursor: 'YXJyYXljb25uZWN0aW9uOjM=',
         hasPreviousPage: false,
         hasNextPage: true,
       }