Imported Upstream version 4.6.0.125

Former-commit-id: a2155e9bd80020e49e72e86c44da02a8ac0e57a4

mcs/class/referencesource/System.Data.Linq/SqlClient/Common/SqlServer2KCompatibilityCheck.cs

@@ -0,0 +1,60 @@
+using System;
+using System.Collections.ObjectModel;
+using System.Text;
+
+namespace System.Data.Linq.SqlClient {
+
+    /// <summary>
+    /// Methods for checking whethe a query was compatible with the
+    /// server it will be sent to.
+    /// </summary>
+    static internal class SqlServerCompatibilityCheck {
+
+        /// <summary>
+        /// Private visitor class checks each node for compatibility annotations.
+        /// </summary>
+        private class Visitor : SqlVisitor {
+
+            private SqlProvider.ProviderMode provider;
+            internal SqlNodeAnnotations annotations;
+
+            internal Visitor(SqlProvider.ProviderMode provider) {
+                this.provider = provider;
+            }
+
+            /// <summary>
+            /// The reasons why this query is not 2K compatible.
+            /// </summary>
+            internal Collection<string> reasons = new Collection<string>();
+
+            internal override SqlNode Visit(SqlNode node) {
+                if (annotations.NodeIsAnnotated(node)) {
+                    foreach (SqlNodeAnnotation annotation in annotations.Get(node)) {
+                        SqlServerCompatibilityAnnotation ssca = annotation as SqlServerCompatibilityAnnotation;
+                        if (ssca != null && ssca.AppliesTo(provider)) {
+                            reasons.Add(annotation.Message);
+                        }
+                    }
+                }
+                return base.Visit(node);
+            }
+        }
+
+        /// <summary>
+        /// Checks whether the given node is supported on the given server.
+        /// </summary>
+        internal static void ThrowIfUnsupported(SqlNode node, SqlNodeAnnotations annotations, SqlProvider.ProviderMode provider) {
+            // Check to see whether there's at least one SqlServerCompatibilityAnnotation.
+            if (annotations.HasAnnotationType(typeof(SqlServerCompatibilityAnnotation))) {
+                Visitor visitor = new Visitor(provider);
+                visitor.annotations = annotations;
+                visitor.Visit(node);
+
+                // If any messages were recorded, then throw an exception.
+                if (visitor.reasons.Count > 0) {
+                    throw Error.ExpressionNotSupportedForSqlServerVersion(visitor.reasons);
+                }
+            }
+        }
+    }
+}