Additional Unit Tests for IndexShard

Description: The main goal of this particular deliverable is to gain some knowledge of what sort of methods are used from an instance of IndexShard. This is sort of accomplished by looking at the unit test code to see what main methods are usually called. From the test cases, the major function of IndexShard is to act as a data structure meant to store either documents or links to documents. This is done by using addDocumentWords(), which takes a document id, a posting list, some meta id, and finally an offset. There is also an additional argument for whether we're adding a document or a link. Once documents have been added, we can then perform a search using getPostingSliceById, which will return a result set containing the all documents that contain a certain word in their posting list. Other operations include taking two IndexShards and combining them together in one bigger one, as well as changing the offset of the documents in the shard. What I did to help in my understanding of what was going on was add additional tests to the existing test cases.

Example:This is just a screenshot of the testing page, showing how many have failed or passed.