adding more logging to failures. (#1555)

* adding more logging to failures.

Author: sfilipi

test/Microsoft.ML.TestFramework/BaseTestBaseline.cs

@@ -517,12 +517,12 @@ private bool GetNumbersFromFile(ref string firstString, ref string secondString,
 
             if (firstCollection.Count == secondCollection.Count)
             {
-                if(!MatchNumberWithTolerance(firstCollection, secondCollection, digitsOfPrecision))
+                if (!MatchNumberWithTolerance(firstCollection, secondCollection, digitsOfPrecision))
                 {
                     return false;
                 }
             }
-                
+
             firstString = MatchNumbers.Replace(firstString, "%Number%");
             secondString = MatchNumbers.Replace(secondString, "%Number%");
             return true;
@@ -551,14 +551,20 @@ private bool MatchNumberWithTolerance(MatchCollection firstCollection, MatchColl
                 // would fail the inRange == true check, but would suceed the following, and we doconsider those two numbers 
                 // (1.82844949 - 1.8284502) = -0.00000071
 
+                double delta2 = 0;
                 if (!inRange)
                 {
-                    delta = Math.Round(f1 - f2, digitsOfPrecision);
-                    inRange = delta >= -allowedVariance && delta <= allowedVariance;
+                    delta2 = Math.Round(f1 - f2, digitsOfPrecision);
+                    inRange = delta2 >= -allowedVariance && delta2 <= allowedVariance;
                 }
 
-                if(!inRange)
+                if (!inRange)
                 {
+                    Fail(_allowMismatch, $"Output and baseline mismatch at line {i}." + Environment.NewLine +
+                        $"Values to compare are {firstCollection[i]} and {secondCollection[i]}" + Environment.NewLine +
+                        $"\t AllowedVariance: {allowedVariance}" + Environment.NewLine +
+                        $"\t delta: {delta}" + Environment.NewLine +
+                        $"\t delta2: {delta2}" + Environment.NewLine);
                     return false;
                 }
             }