private SqlExpression ExpandTogether(List <SqlExpression> exprs)
{
switch (exprs[0].NodeType)
{
case SqlNodeType.MethodCall: {
SqlMethodCall[] mcs = new SqlMethodCall[exprs.Count];
for (int i = 0; i < mcs.Length; ++i)
{
mcs[i] = (SqlMethodCall)exprs[i];
}
List <SqlExpression> expandedArgs = new List <SqlExpression>();
for (int i = 0; i < mcs[0].Arguments.Count; ++i)
{
List <SqlExpression> args = new List <SqlExpression>();
for (int j = 0; j < mcs.Length; ++j)
{
args.Add(mcs[j].Arguments[i]);
}
SqlExpression expanded = this.ExpandTogether(args);
expandedArgs.Add(expanded);
}
return(factory.MethodCall(mcs[0].Method, mcs[0].Object, expandedArgs.ToArray(), mcs[0].SourceExpression));
}
case SqlNodeType.ClientCase: {
// Are they all the same?
SqlClientCase[] scs = new SqlClientCase[exprs.Count];
scs[0] = (SqlClientCase)exprs[0];
for (int i = 1; i < scs.Length; ++i)
{
scs[i] = (SqlClientCase)exprs[i];
}
// Expand expressions together.
List <SqlExpression> expressions = new List <SqlExpression>();
for (int i = 0; i < scs.Length; ++i)
{
expressions.Add(scs[i].Expression);
}
SqlExpression expression = this.ExpandTogether(expressions);
// Expand individual expressions together.
List <SqlClientWhen> whens = new List <SqlClientWhen>();
for (int i = 0; i < scs[0].Whens.Count; ++i)
{
List <SqlExpression> scos = new List <SqlExpression>();
for (int j = 0; j < scs.Length; ++j)
{
SqlClientWhen when = scs[j].Whens[i];
scos.Add(when.Value);
}
whens.Add(new SqlClientWhen(scs[0].Whens[i].Match, this.ExpandTogether(scos)));
}
return(new SqlClientCase(scs[0].ClrType, expression, whens, scs[0].SourceExpression));
}
case SqlNodeType.TypeCase: {
// Are they all the same?
SqlTypeCase[] tcs = new SqlTypeCase[exprs.Count];
tcs[0] = (SqlTypeCase)exprs[0];
for (int i = 1; i < tcs.Length; ++i)
{
tcs[i] = (SqlTypeCase)exprs[i];
}
// Expand discriminators together.
List <SqlExpression> discriminators = new List <SqlExpression>();
for (int i = 0; i < tcs.Length; ++i)
{
discriminators.Add(tcs[i].Discriminator);
}
SqlExpression discriminator = this.ExpandTogether(discriminators);
// Write expanded discriminators back in.
for (int i = 0; i < tcs.Length; ++i)
{
tcs[i].Discriminator = discriminators[i];
}
// Expand individual type bindings together.
List <SqlTypeCaseWhen> whens = new List <SqlTypeCaseWhen>();
for (int i = 0; i < tcs[0].Whens.Count; ++i)
{
List <SqlExpression> scos = new List <SqlExpression>();
for (int j = 0; j < tcs.Length; ++j)
{
SqlTypeCaseWhen when = tcs[j].Whens[i];
scos.Add(when.TypeBinding);
}
SqlExpression expanded = this.ExpandTogether(scos);
whens.Add(new SqlTypeCaseWhen(tcs[0].Whens[i].Match, expanded));
}
return(factory.TypeCase(tcs[0].ClrType, tcs[0].RowType, discriminator, whens, tcs[0].SourceExpression));
}
case SqlNodeType.New: {
// first verify all are similar client objects...
SqlNew[] cobs = new SqlNew[exprs.Count];
cobs[0] = (SqlNew)exprs[0];
for (int i = 1, n = exprs.Count; i < n; i++)
{
if (exprs[i] == null || exprs[i].NodeType != SqlNodeType.New)
{
throw Error.UnionIncompatibleConstruction();
}
cobs[i] = (SqlNew)exprs[1];
if (cobs[i].Members.Count != cobs[0].Members.Count)
{
throw Error.UnionDifferentMembers();
}
for (int m = 0, mn = cobs[0].Members.Count; m < mn; m++)
{
if (cobs[i].Members[m].Member != cobs[0].Members[m].Member)
{
throw Error.UnionDifferentMemberOrder();
}
}
}
SqlMemberAssign[] bindings = new SqlMemberAssign[cobs[0].Members.Count];
for (int m = 0, mn = bindings.Length; m < mn; m++)
{
List <SqlExpression> mexprs = new List <SqlExpression>();
for (int i = 0, n = exprs.Count; i < n; i++)
{
mexprs.Add(cobs[i].Members[m].Expression);
}
bindings[m] = new SqlMemberAssign(cobs[0].Members[m].Member, this.ExpandTogether(mexprs));
for (int i = 0, n = exprs.Count; i < n; i++)
{
cobs[i].Members[m].Expression = mexprs[i];
}
}
SqlExpression[] arguments = new SqlExpression[cobs[0].Args.Count];
for (int m = 0, mn = arguments.Length; m < mn; ++m)
{
List <SqlExpression> mexprs = new List <SqlExpression>();
for (int i = 0, n = exprs.Count; i < n; i++)
{
mexprs.Add(cobs[i].Args[m]);
}
arguments[m] = ExpandTogether(mexprs);
}
return(factory.New(cobs[0].MetaType, cobs[0].Constructor, arguments, cobs[0].ArgMembers, bindings, exprs[0].SourceExpression));
}
case SqlNodeType.Link: {
SqlLink[] links = new SqlLink[exprs.Count];
links[0] = (SqlLink)exprs[0];
for (int i = 1, n = exprs.Count; i < n; i++)
{
if (exprs[i] == null || exprs[i].NodeType != SqlNodeType.Link)
{
throw Error.UnionIncompatibleConstruction();
}
links[i] = (SqlLink)exprs[i];
if (links[i].KeyExpressions.Count != links[0].KeyExpressions.Count ||
links[i].Member != links[0].Member ||
(links[i].Expansion != null) != (links[0].Expansion != null))
{
throw Error.UnionIncompatibleConstruction();
}
}
SqlExpression[] kexprs = new SqlExpression[links[0].KeyExpressions.Count];
List <SqlExpression> lexprs = new List <SqlExpression>();
for (int k = 0, nk = links[0].KeyExpressions.Count; k < nk; k++)
{
lexprs.Clear();
for (int i = 0, n = exprs.Count; i < n; i++)
{
lexprs.Add(links[i].KeyExpressions[k]);
}
kexprs[k] = this.ExpandTogether(lexprs);
for (int i = 0, n = exprs.Count; i < n; i++)
{
links[i].KeyExpressions[k] = lexprs[i];
}
}
SqlExpression expansion = null;
if (links[0].Expansion != null)
{
lexprs.Clear();
for (int i = 0, n = exprs.Count; i < n; i++)
{
lexprs.Add(links[i].Expansion);
}
expansion = this.ExpandTogether(lexprs);
for (int i = 0, n = exprs.Count; i < n; i++)
{
links[i].Expansion = lexprs[i];
}
}
return(new SqlLink(links[0].Id, links[0].RowType, links[0].ClrType, links[0].SqlType, links[0].Expression, links[0].Member, kexprs, expansion, links[0].SourceExpression));
}
case SqlNodeType.Value: {
/*
* ExprSet of all literals of the same value reduce to just a single literal.
*/
SqlValue val0 = (SqlValue)exprs[0];
for (int i = 1; i < exprs.Count; ++i)
{
SqlValue val = (SqlValue)exprs[i];
if (!object.Equals(val.Value, val0.Value))
{
return(this.ExpandIntoExprSet(exprs));
}
}
return(val0);
}
case SqlNodeType.OptionalValue: {
if (exprs[0].SqlType.CanBeColumn)
{
goto default;
}
List <SqlExpression> hvals = new List <SqlExpression>(exprs.Count);
List <SqlExpression> vals = new List <SqlExpression>(exprs.Count);
for (int i = 0, n = exprs.Count; i < n; i++)
{
if (exprs[i] == null || exprs[i].NodeType != SqlNodeType.OptionalValue)
{
throw Error.UnionIncompatibleConstruction();
}
SqlOptionalValue sov = (SqlOptionalValue)exprs[i];
hvals.Add(sov.HasValue);
vals.Add(sov.Value);
}
return(new SqlOptionalValue(this.ExpandTogether(hvals), this.ExpandTogether(vals)));
}
case SqlNodeType.OuterJoinedValue: {
if (exprs[0].SqlType.CanBeColumn)
{
goto default;
}
List <SqlExpression> values = new List <SqlExpression>(exprs.Count);
for (int i = 0, n = exprs.Count; i < n; i++)
{
if (exprs[i] == null || exprs[i].NodeType != SqlNodeType.OuterJoinedValue)
{
throw Error.UnionIncompatibleConstruction();
}
SqlUnary su = (SqlUnary)exprs[i];
values.Add(su.Operand);
}
return(factory.Unary(SqlNodeType.OuterJoinedValue, this.ExpandTogether(values)));
}
case SqlNodeType.DiscriminatedType: {
SqlDiscriminatedType sdt0 = (SqlDiscriminatedType)exprs[0];
List <SqlExpression> foos = new List <SqlExpression>(exprs.Count);
foos.Add(sdt0.Discriminator);
for (int i = 1, n = exprs.Count; i < n; i++)
{
SqlDiscriminatedType sdtN = (SqlDiscriminatedType)exprs[i];
if (sdtN.TargetType != sdt0.TargetType)
{
throw Error.UnionIncompatibleConstruction();
}
foos.Add(sdtN.Discriminator);
}
return(factory.DiscriminatedType(this.ExpandTogether(foos), ((SqlDiscriminatedType)exprs[0]).TargetType));
}
case SqlNodeType.ClientQuery:
case SqlNodeType.Multiset:
case SqlNodeType.Element:
case SqlNodeType.Grouping:
throw Error.UnionWithHierarchy();
default:
return(this.ExpandIntoExprSet(exprs));
}
}
internal override SqlExpression VisitValue(SqlValue value)
{
return(value);
}
internal override SqlNode Visit(SqlNode node)
{
if (node == null)
{
return(null);
}
sourceExpression = node as SqlExpression;
if (sourceExpression != null)
{
Type type = sourceExpression.ClrType;
UnwrapStack unwrap = this.UnwrapSequences;
while (unwrap != null)
{
if (unwrap.Unwrap)
{
type = TypeSystem.GetElementType(type);
}
unwrap = unwrap.Last;
}
sourceType = type;
}
if (sourceType != null && TypeSystem.GetNonNullableType(sourceType).IsValueType)
{
return(node); // Value types can't also have a dynamic type.
}
if (sourceType != null && TypeSystem.HasIEnumerable(sourceType))
{
return(node); // Sequences can't be polymorphic.
}
switch (node.NodeType)
{
case SqlNodeType.ScalarSubSelect:
case SqlNodeType.Multiset:
case SqlNodeType.Element:
case SqlNodeType.SearchedCase:
case SqlNodeType.ClientCase:
case SqlNodeType.SimpleCase:
case SqlNodeType.Member:
case SqlNodeType.DiscriminatedType:
case SqlNodeType.New:
case SqlNodeType.FunctionCall:
case SqlNodeType.MethodCall:
case SqlNodeType.Convert: // Object identity does not survive convert. It does survive Cast.
// Dig no further.
return(node);
case SqlNodeType.TypeCase:
sourceType = ((SqlTypeCase)node).RowType.Type;
return(node);
case SqlNodeType.Link:
sourceType = ((SqlLink)node).RowType.Type;
return(node);
case SqlNodeType.Table:
sourceType = ((SqlTable)node).RowType.Type;
return(node);
case SqlNodeType.Value:
SqlValue val = (SqlValue)node;
if (val.Value != null)
{
// In some cases the ClrType of a Value node may
// differ from the actual runtime type of the value.
// Therefore, we ensure here that the correct type is set.
sourceType = val.Value.GetType();
}
return(node);
}
return(base.Visit(node));
}
internal override SqlExpression VisitValue(SqlValue value) => value;
