Make corpus alignment exceptions more generic

src/SIL.Machine/Corpora/CorporaExtensions.cs

@@ -52,6 +52,17 @@ public static (IEnumerable<(T, bool)>, int, int) InterleavedSplit<T>(
             return (splitCorpus, corpusSize - splitIndices.Count, splitIndices.Count);
         }
 
+        public static ArgumentException AlignmentException<T>(
+            this ICorpus<T> _,
+            string[] refs,
+            Exception innerException = null
+        )
+            where T : IRow =>
+            new ArgumentException(
+                $"Invalid format in {string.Join(", ", refs)}. Mismatched key formats. There may be an extraneous tab, missing ref, or inconsistent use of user-defined refs.",
+                innerException
+            );
+
         #endregion
 
         #region ITextCorpus operations

src/SIL.Machine/Corpora/NParallelTextCorpus.cs

@@ -142,7 +142,7 @@ private IEnumerable<NParallelTextRow> GetRows(IList<IEnumerator<TextRow>> enumer
                 }
                 catch (ArgumentException e)
                 {
-                    throw new CorpusAlignmentException(
+                    throw this.AlignmentException(
                         currentRows.Where(r => r != null).Select(r => r.Ref.ToString()).ToArray(),
                         e
                     );
@@ -264,9 +264,7 @@ NParallelTextRow row in CreateRows(
                 }
                 else
                 {
-                    throw new CorpusAlignmentException(
-                        minRefIndexes.Select(i => currentRows[i].Ref.ToString()).ToArray()
-                    );
+                    throw this.AlignmentException(minRefIndexes.Select(i => currentRows[i].Ref.ToString()).ToArray());
                 }
             }
 
@@ -400,7 +398,7 @@ private bool CheckSameRefRows(IList<TextRow> sameRefRows, TextRow otherRow)
             }
             catch (ArgumentException e)
             {
-                throw new CorpusAlignmentException(sameRefRows[0].Ref.ToString(), otherRow.Ref.ToString(), e);
+                throw this.AlignmentException(new[] { sameRefRows[0].Ref.ToString(), otherRow.Ref.ToString() }, e);
             }
             return sameRefRows.Count > 0;
         }

src/SIL.Machine/Corpora/ParallelTextCorpus.cs

@@ -54,7 +54,7 @@ public override IEnumerable<ParallelTextRow> GetRows(IEnumerable<string> textIds
                             }
                             catch (ArgumentException e)
                             {
-                                throw new CorpusAlignmentException(nRow.NRefs.Select(r => r.ToString()).ToArray(), e);
+                                throw this.AlignmentException(nRow.NRefs.Select(r => r.ToString()).ToArray(), e);
                             }
                         } while (compareAlignmentCorpus < 0);
                     }