[IGNITE-18120] .NET: Thin 3.0: Allow arbitrary MemberInit projections in LINQ

• Type: Improvement
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 3.0.0-beta2
• Component/s: platforms
• Labels: .NET LINQ ignite-3
• Assignee: Sergey Stronchinskiy
• Reporter: Pavel Tupitsyn
• Created: 11/Nov/22 06:47
• Updated: 08/Apr/23 13:36
• Resolved: 07/Apr/23 14:59

Description

Ignite LINQ provider allows anonymous type projections:

query.Select(emp => new {Id = emp.Key, Name = emp.Value.Name});

However, it does not work with a custom class:

query.Select(emp => new Foo {Id = emp.Key, Name = emp.Value.Name});

throws exception:

System.NotSupportedException : The expression 'new Foo() {Id = [x].Key}' (type: System.Linq.Expressions.MemberInitExpression) is not supported.

Add VisitMemberInit overload to CacheQueryExpressionVisitor to support this scenario. See linked SO page for more details - there is a proposed fix as well.

Issue Links

• causes: IGNITE-19260 .NET: Thin 3.0: Support nested MemberInit projections in LINQ
• is a clone of: IGNITE-14343 .NET: Allow arbitrary MemberInit projections in LINQ
• is blocked by: IGNITE-17343 .NET: Thin 3.0: LINQ provider
• relates to: IGNITE-19256 .NET: Thin 3.0: Document MemberInit projections in LINQ
• links to: GitHub Pull Request #1906
• links to: Stackoverflow: Ignite LINQ provider projection support for non-anonymous types