"new" keyword in C# throws error

[jagprog5]

semgrep version v1.70.0

rules:
  - id: id-here
    languages:
      - csharp
    severity: WARNING
    message: HashAlgorithm $NAME detected
    patterns:
      - pattern: new System.Security.Cryptography.HashAlgorithmName("$NAME")
      - metavariable-pattern:
          metavariable: $NAME
          pattern-either:
            - pattern: SHA3_384
            - pattern: SHA3_256
            - pattern: SHA384
            - pattern: SHA256
            - pattern: SHA1
            - pattern: MD5
            - pattern: SHA3_512
            - pattern: SHA512

test code:

using System.Security.Cryptography;

class Program {
    static void Main() {
        HashAlgorithmName name = new HashAlgorithmName("SHA1");
    }
}

Adding the word "new" in the above rule causes the following error:

Internal matching error when running hashname-standard-lib-c-sharp on target.cs:
 An error occurred while invoking the Semgrep engine. Please help us fix this by creating an issue at https://github.com/returntocorp/semgrep

metavariable-pattern failed because $NAME does not bind to a sub-program, please check your rule

My workaround is to replace the above metavariable-pattern with an equivalent metavariable-regex.

What is the priority of the bug to you?

• P0: blocking your adoption of Semgrep or workflow
• P1: important to fix or quite annoying
• P2: regular bug that should get fixed

Environment
Semgrep playground

[amchiclet]

Reduced the test. The issue seems to be language-agnostic.

# python code
f("some-name")

This rule causes the error: metavariable-pattern failed because $NAME does not bind to a sub-program, please check your rule

rules:
  - id: some-id
    languages:
      - python
    severity: WARNING
    message: some-message
    patterns:
      - pattern: f("$NAME")
      - metavariable-pattern:
          metavariable: $NAME
          pattern: some-name