[MINOR] Frame convert test cover

Closes #2114

Author: Baunsgaard

src/main/java/org/apache/sysds/runtime/frame/data/lib/FrameFromMatrixBlock.java

@@ -86,19 +86,13 @@ private static ValueType[] getSchema(MatrixBlock mb) {
 		final int nRow = mb.getNumRows();
 		// default boolean if possible.
 		final ValueType[] schema = UtilFunctions.nCopies(nCol, ValueType.BOOLEAN);
-		for(int c = 0; c < nCol; c++){
-			for(int r = 0; r < nRow; r++){
-				switch(schema[c]){
-					case INT64:
-						// keep the type as FP64 if long is detected
-						schema[c] = ValueType.FP64; 
+		for(int c = 0; c < nCol; c++) {
+			for(int r = 0; r < nRow; r++) {
+				switch(schema[c]) {
 					case FP64:
-						break;
+						break; // early termination of column default to highest
 					default:
-						final double v =  mb.get(r, c);
-						if(v > Integer.MAX_VALUE)
-							schema[c] = ValueType.FP64; // handle Integer overflow.
-						schema[c] = FrameUtil.isType(v, schema[c]);
+						schema[c] = FrameUtil.isType(mb.get(r, c), schema[c]);
 				}
 			}
 		}
@@ -114,15 +108,13 @@ else if(mb.isInSparseFormat())
 				convertToFrameBlockSparse();
 			else
 				convertToFrameBlockDense();
-			if(frame.getNumRows() != mb.getNumRows())
-				throw new DMLRuntimeException("Invalid result");
 
 			return frame;
 		}
-		catch(InterruptedException | ExecutionException e) {
-			throw new DMLRuntimeException("failed to convert to matrix block");
+		catch(Exception e) {
+			throw new DMLRuntimeException("failed to convert to matrix block", e);
 		}
-		finally{
+		finally {
 			if(pool != null)
 				pool.shutdown();
 		}

src/main/java/org/apache/sysds/runtime/frame/data/lib/FrameLibCompress.java

@@ -22,7 +22,7 @@
 import org.apache.sysds.runtime.frame.data.FrameBlock;
 import org.apache.sysds.runtime.frame.data.compress.CompressedFrameBlockFactory;
 
-public class FrameLibCompress {
+public interface FrameLibCompress {
 
 	public static FrameBlock compress(FrameBlock in, int k) {
 		return compress(in, k, null);

src/test/java/org/apache/sysds/test/component/frame/FrameCustomTest.java

@@ -35,7 +35,7 @@ public void castToFrame() {
 		double maxp1 = Integer.MAX_VALUE + 1.0;
 		MatrixBlock mb = TestUtils.generateTestMatrixBlock(100, 100, maxp1, maxp1, 1.0, 23);
 		FrameBlock f = DataConverter.convertToFrameBlock(mb);
-		assertTrue(f.getSchema()[0] == ValueType.FP64);
+		assertTrue(f.getSchema()[0] == ValueType.INT64);
 	}
 
 	@Test
@@ -47,10 +47,10 @@ public void castToFrame3() {
 	}
 
 	@Test
-	public void castErrorValue() {
+	public void castIntegerValue() {
 		MatrixBlock mb = new MatrixBlock(10, 10, Double.parseDouble("2.572306572E9"));
 		FrameBlock f = DataConverter.convertToFrameBlock(mb);
-		assertTrue(f.getSchema()[0] == ValueType.FP64);
+		assertTrue(f.getSchema()[0] == ValueType.INT64);
 	}
 
 	@Test

src/test/java/org/apache/sysds/test/component/frame/FrameFromMatrixBlockTest.java

@@ -19,12 +19,16 @@
 package org.apache.sysds.test.component.frame;
 
 import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertThrows;
 import static org.junit.Assert.assertTrue;
 import static org.junit.Assert.fail;
+import static org.mockito.Mockito.spy;
+import static org.mockito.Mockito.when;
 
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
 import org.apache.sysds.common.Types.ValueType;
+import org.apache.sysds.runtime.DMLRuntimeException;
 import org.apache.sysds.runtime.data.DenseBlockFP64;
 import org.apache.sysds.runtime.frame.data.FrameBlock;
 import org.apache.sysds.runtime.frame.data.lib.FrameFromMatrixBlock;
@@ -162,6 +166,17 @@ public void randomVerySparse() {
 		verifyEquivalence(mb, fb);
 	}
 
+	@Test
+	public void error(){
+		MatrixBlock mb = TestUtils.ceil(TestUtils.generateTestMatrixBlock(1000, 1, 0, 199, 0.01, 213));
+		MatrixBlock spy = spy(mb);
+		when(spy.isEmpty()).thenThrow(new DMLRuntimeException("Intended Error"));
+		Exception e = assertThrows(DMLRuntimeException.class, () -> FrameFromMatrixBlock.convertToFrameBlock(spy, new ValueType[]{ValueType.FP64}, 1));
+		assertTrue(e.getMessage().contains("failed to convert to matrix block"));
+	}
+
+
+
 	// @Test
 	// public void timeChange() {
 		// MatrixBlock mb = TestUtils.generateTestMatrixBlock(64000, 2000, 1, 1, 0.5, 2340);