add ut and exclude

Author: hhbyyh

mllib/src/main/scala/org/apache/spark/mllib/linalg/Matrices.scala

@@ -87,8 +87,8 @@ sealed trait Matrix extends Serializable {
   /** A human readable representation of the matrix */
   override def toString: String = toBreeze.toString()
 
-  /** A human readable representation of the matrix with specific lines and width */
-  def toString(maxLines: Int, maxWidth: Int): String = toBreeze.toString(maxLines, maxWidth)
+  /** A human readable representation of the matrix with maximum lines and width */
+  def toString(maxLines: Int, maxLineWidth: Int): String = toBreeze.toString(maxLines, maxLineWidth)
 
   /** Map the values of this matrix using a function. Generates a new matrix. Performs the
     * function on only the backing array. For example, an operation such as addition or

mllib/src/test/scala/org/apache/spark/mllib/linalg/MatricesSuite.scala

@@ -439,4 +439,20 @@ class MatricesSuite extends FunSuite {
     assert(mUDT.typeName == "matrix")
     assert(mUDT.simpleString == "matrix")
   }
+
+  test("toString") {
+    val empty = Matrices.ones(0, 0)
+    empty.toString(0, 0)
+
+    val mat = Matrices.rand(5, 10, new Random())
+    mat.toString(-1, -5)
+    mat.toString(0, 0)
+    mat.toString(Int.MinValue, Int.MinValue)
+    mat.toString(Int.MaxValue, Int.MaxValue)
+    var lines = mat.toString(6, 50).lines.toArray
+    assert(lines.size == 5 && lines.forall(_.size <= 50))
+
+    lines = mat.toString(5, 100).lines.toArray
+    assert(lines.size == 5 && lines.forall(_.size <= 100))
+  }
 }

project/MimaExcludes.scala

@@ -64,8 +64,12 @@ object MimaExcludes {
             // SPARK-6492 Fix deadlock in SparkContext.stop()
             ProblemFilters.exclude[MissingMethodProblem]("org.apache.spark.SparkContext.org$" +
                 "apache$spark$SparkContext$$SPARK_CONTEXT_CONSTRUCTOR_LOCK")
+          )++ Seq(
+            // SPARK-6693 add tostring with max lines and width for matrix
+            ProblemFilters.exclude[MissingMethodProblem]("org.apache.spark.mllib.linalg.Matrix.toString")
           )
 
+
         case v if v.startsWith("1.3") =>
           Seq(
             MimaBuild.excludeSparkPackage("deploy"),