1 files changed, 52 insertions, 0 deletions
diff --git a/test/junit/scala/reflect/internal/util/StringOpsTest.scala b/test/junit/scala/reflect/internal/util/StringOpsTest.scala
new file mode 100644
index 0000000000..13d3a6435e
--- /dev/null
+++ b/test/junit/scala/reflect/internal/util/StringOpsTest.scala
@@ -0,0 +1,52 @@
+package scala.reflect.internal.util
+
+import org.junit.Assert._
+import org.junit.Test
+import org.junit.runner.RunWith
+import org.junit.runners.JUnit4
+
+@RunWith(classOf[JUnit4])
+class StringOpsTest {
+  @Test
+  def prefixOfNone(): Unit = {
+    val so = new StringOps { }
+    val ss = Nil
+    val lcp = so longestCommonPrefix ss
+    assert(lcp == "")
+  }
+  @Test
+  def prefixWithEmpty(): Unit = {
+    val so = new StringOps { }
+    val ss = List("abc", "", "abd")
+    val lcp = so longestCommonPrefix ss
+    assert(lcp == "")
+  }
+  @Test
+  def prefixOfOne(): Unit = {
+    val so = new StringOps { }
+    val ss = List("abc")
+    val lcp = so longestCommonPrefix ss
+    assert(lcp == "abc")
+  }
+  @Test
+  def prefixOfMany(): Unit = {
+    val so = new StringOps { }
+    val ss = List("abc", "abd", "abe")
+    val lcp = so longestCommonPrefix ss
+    assert(lcp == "ab")
+  }
+  @Test
+  def prefixOfPrefix(): Unit = {
+    val so = new StringOps { }
+    val ss = List("abc", "abcd")
+    val lcp = so longestCommonPrefix ss
+    assert(lcp == "abc")
+  }
+  @Test
+  def prefixOfPrefixMiddling(): Unit = {
+    val so = new StringOps { }
+    val ss = List("abce", "abc", "abcd")
+    val lcp = so longestCommonPrefix ss
+    assert(lcp == "abc")
+  }
+}