Fix S1144 FP: types used through reflection

[zsolt-kolbay-sonarsource]

Fixes #9379

RSpec change: SonarSource/rspec#3992

[martin-strecker-sonarsource]

It generally looks fine. It misses some UTs that might be worth adding. Feel free not to add them if you think it's not worth it.

[zsolt-kolbay-sonarsource]

I removed the check through type parameters, because it nearly doubled the analysis time.
We'll need to accept it as FP.

[martin-strecker-sonarsource]

I removed the check through type parameters, because it nearly doubled the analysis time.
We'll need to accept it as FP.

How did you measure? If the rule was very, very fast, duplication is not a problem. Can you post some more info about the perf validation?

[zsolt-kolbay-sonarsource]

I removed the check through type parameters, because it nearly doubled the analysis time.
We'll need to accept it as FP.

How did you measure? If the rule was very, very fast, duplication is not a problem. Can you post some more info about the perf validation?

I used the AnalyzerRunner from the Roslyn repo to compare the performance with and without the check for type parameters. I ran it on AutoMapper, Akka.Net, and an earlier version of the Roslyn repo. They all showed a degradation in performance ranging between 40% and 90%. UnusedPrivateMember is one of the slowest rules we have (excluding SE rules), so I don't think such a change is acceptable.

WITHOUT the check for type arguments (AutoMapper):

Statistics for UnusedPrivateMember:
Concurrent:                     False
Execution time (ms):            3644.8062
Code Block Actions:             0
Code Block Start Actions:       0
Code Block End Actions:         0
Compilation Actions:            0
Compilation Start Actions:      6
Compilation End Actions:        6
Operation Actions:              0
Operation Block Actions:        0
Operation Block Start Actions:  0
Operation Block End Actions:    0
Semantic Model Actions:         0
Symbol Actions:                 6
Symbol Start Actions:           0
Symbol End Actions:             0
Syntax Node Actions:            0
Syntax Tree Actions:            0
Additional File Actions:        0
Suppression Actions:            0
Execution times (ms):
UnusedPrivateMember:    3645
  S1144: 1364 instances
  S4487: 9 instances

--------------------------------------------------------
--------------------------------------------------------

INCLUDING the check for type arguments (AutoMapper):

Statistics for UnusedPrivateMember:
Concurrent:                     False
Execution time (ms):            5731.9556
Code Block Actions:             0
Code Block Start Actions:       0
Code Block End Actions:         0
Compilation Actions:            0
Compilation Start Actions:      6
Compilation End Actions:        6
Operation Actions:              0
Operation Block Actions:        0
Operation Block Start Actions:  0
Operation Block End Actions:    0
Semantic Model Actions:         0
Symbol Actions:                 6
Symbol Start Actions:           0
Symbol End Actions:             0
Syntax Node Actions:            0
Syntax Tree Actions:            0
Additional File Actions:        0
Suppression Actions:            0
Execution times (ms):
UnusedPrivateMember:    5732
  S1144: 1364 instances
  S4487: 9 instances

[martin-strecker-sonarsource]

Can you also update the RSpec? It needs the DynamicallyAccessedMembersAttribute in the exception section. Consider only checking only the name of the attribute instead of namespace/name. This would allow users to create this attribute in unsupported platforms (which is every platform except Net5 upwards). The name is long enough to not be confused with anything else. If you go that route, tests are needed.

[martin-strecker-sonarsource]

LGTM. I think a comment is helpful in this case.

[sonarcloud]

Quality Gate passed for 'Sonar .NET Java Plugin'

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
No data about Coverage
No data about Duplication

See analysis details on SonarCloud

[sonarcloud]

Quality Gate passed for 'SonarAnalyzer for .NET'

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
95.7% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarCloud