1 files changed, 118 insertions, 0 deletions
diff --git a/spellchecker/test/SpellCorrectorTest.java b/spellchecker/test/SpellCorrectorTest.java
new file mode 100644
index 0000000..dbea0ab
--- /dev/null
+++ b/spellchecker/test/SpellCorrectorTest.java
@@ -0,0 +1,118 @@
+
+import java.io.IOException;
+import java.util.HashSet;
+import java.util.Set;
+import org.junit.Test;
+import static org.junit.Assert.*;
+import org.junit.Before;
+
+/**
+ * @author Peter Wu
+ */
+public class SpellCorrectorTest {
+
+    private CorpusReader fullCR;
+
+    @Before
+    public void setUp() throws IOException {
+        fullCR = new MockCorpusReader();
+    }
+
+    private void checkGetCandidateWords(CorpusReader cr, String word,
+            Set<String> expResult)
+            throws IOException {
+        System.out.println("getCandidateWords(" + word + ")");
+        SpellCorrector instance = new SpellCorrector(cr, null);
+        HashSet<String> result = instance.getCandidateWords(word);
+        // quick check: are the results of the same size?
+        assertEquals(expResult.size(), result.size());
+        // verbose test: are all letters as expected?
+        assertEquals(expResult, result);
+    }
+
+    @Test
+    public void testGetCandidateWords0() throws IOException {
+        Set<String> words = new HashSet<>();
+
+        // test for empty word (only a letter can be inserted)
+        for (char c : SpellCorrector.ALPHABET) {
+            // insertion
+            words.add("" + c);
+        }
+        checkGetCandidateWords(fullCR, "", words);
+    }
+
+    @Test
+    public void testGetCandidateWords1() throws IOException {
+        Set<String> words = new HashSet<>();
+
+        // test for a single letter word
+        for (char c : SpellCorrector.ALPHABET) {
+            // insertion before and after
+            words.add(c + "a");
+            words.add("a" + c);
+            // substitution should replace the letter.
+            words.add("" + c);
+        }
+        // deletion should not yield a string
+        //words.add("");
+        checkGetCandidateWords(fullCR, "a", words);
+    }
+
+    @Test
+    public void testGetCandidateWords2() throws IOException {
+        Set<String> words = new HashSet<>();
+        // test for a two letter word
+        for (char c : SpellCorrector.ALPHABET) {
+            // insertion before and after
+            words.add(c + "up");
+            words.add("u" + c + "p");
+            words.add("up" + c);
+            // substitution should replace the letter.
+            words.add(c + "p");
+            words.add("u" + c);
+        }
+        // deletion
+        words.add("p");
+        words.add("u");
+        checkGetCandidateWords(fullCR, "up", words);
+    }
+
+    @Test
+    public void testGetCandidateWords3() throws IOException {
+        Set<String> words = new HashSet<>();
+        // test for a three letter word
+        for (char c : SpellCorrector.ALPHABET) {
+            // insertion before and after
+            words.add(c + "ups");
+            words.add("u" + c + "ps");
+            words.add("up" + c + "s");
+            words.add("ups" + c);
+            // substitution should replace the letter.
+            words.add(c + "ps");
+            words.add("u" + c + "s");
+            words.add("up" + c);
+        }
+        // deletion
+        words.add("ps");
+        words.add("us");
+        words.add("up");
+        checkGetCandidateWords(fullCR, "ups", words);
+    }
+
+    /**
+     * Fake CorpusReader which tests whether getCandidateWords can produce all
+     * words.
+     */
+    private class MockCorpusReader extends CorpusReader {
+
+        public MockCorpusReader() throws IOException {
+            super();
+        }
+
+        @Override
+        public HashSet<String> inVocabulary(Set<String> set) {
+            return new HashSet<>(set);
+        }
+    }
+}