FxCop Custom Rule: To check for variable name

FxCop Custom Rule: To check for variable name

• gau2902

  Hi,

  variables inside a method are also called Locals. Please note that names of locals can only be resolved if pdb's are present (compile your project with /debug)

  To retrieve locals inside a method do something like this:

  public override ProblemCollection Check(Member member) { Method method = member as Method; if (method == null) return null; //abstract method, interface etc... if (method.Instructions == null || method.Instructions.Length == 0) return null; LocalList locals = method.Instructions[0] as LocalList; if (locals == null) return null; foreach(Local local in locals) { //do work } }

  
  

• S M Hasan

  Hi,

  Thnx for the reply. I have tried the following code.

  public override ProblemCollection Check(Member member)

  {

  Method method = member as Method;

  if (method == null)

  {

  return null;

  }

  LocalList list = null;

  if (method.Instructions.Length > 0)

  {

  list = method.Instructions[0].Value as LocalList;

  }

  if (list != null)

  {

  for (int i = 0; i < list.Length; i++)

  {

  Local local = list;

  if (local.Type == SystemTypes.Boolean)

  {

  if (Containsb(local.Name.Name))

  {

  // Found a local boolean not containing b

  base.Problems.Add(new Problem(base.GetResolution(local.Name.Name), local.Name.Name));

  }

  }

  }

  }

  return base.Problems;

  }

  private bool Containsb(string variableName)

  {

  if (!(variableName.StartsWith("b")))

  {

  return true;

  }

  else

  {

  return false;

  }

  }

  }

  The problem with the above code is that it also checks for function return types, property having boolean as return type. I need to check for only local variables . Also I was trying this code for Date Variables In case of date it gave error messages for Variables like _VB_DATE_0, _VB_DATE_1 and so on which are actually not present in the code.

  So can anyone please help me:

  a) To check for only local variables

  b) In case of Date variables what are the variables _Vb_Date_0, _Vb_Date_1 ... signify These are not present in the code been analysed.

  Regards

  Ashish

  
  
  

• Vitalijus

  Below is the code of the function  having Boolean as return type:

  Private Function IsAddressFull(ByVal tInputParam As xyz.Cl.cAddress) As Boolean

  Dim bFullClAchieved As Boolean

  Dim dicStates As abc.Collect.Dictionary

  Dim sCountry As String

  Dim bStateReqlfilled As Boolean

  Dim bZipCodelfilled As Boolean

  Try

  With tInputParam

  if IsStringNull(.sCountry) = False Then

  sCountry = .sCountry

  Else

  sCountry = CountryS

  End If

  Return bFullClAchieved

  Finally

  Cleanup(dicStates)

  dicStates = Nothing

  End Try

  End Function

  So when I run the custom Rule it gives me error the following error:

  Target : IsAddressFull():System.Boolean (IntrospectionTargetMethodBase)

  Id : IsAddressFull (String)

  Location : file:///C://ABAddr.aspx.vb<1127> (String)

  Resolution : "Add prefix b to variable 'IsAddressFull'"

  Help : http://www.dla.mil/ (String)

  Category : Design Rules (String)

  CheckId : DR0051 (String)

  RuleFile : CodingStandards.dll (String)

  Info : "Boolean Variable should start with b as prefix."

  Created : 3/1/2006 1:04:04 PM (DateTime)

  LastSeen : 3/1/2006 1:04:04 PM (DateTime)

  Status : Active (MessageStatus)

  Fix Category : NonBreaking (FixCategories)

  }

   

  Same is the case with other functions having return type as Boolean.

  
  
  

• ryuga99

  I'm a little confused as to the return value having the same name as the function, do mean like the following pattern:

  Private Function IsAddressNull(ByVal branch As Boolean, ByVal branch2 As Boolean) As Boolean IsAddressNull = True End Function

  If so, I've done a few tests and I can't get the IsAddressNull name to be persisted as a local variable. Can you post a sample where you can

  If you are able to get the IsAddressNull to persist as a local variable, you could check the name of each variable against the name of the method that it is defined on and if they match, ignore it.

  
  
  

• theinspector

  Thanks, looks like the VB compiler is creating this variable in certain situations.

  Even though this is the case, my last paragraph still stands:

  If you are able to get the IsAddressNull to persist as a local variable, you could check the name of each variable against the name of the method that it is defined on and if they match, ignore it.
  

  
  
  

• Nidhogg

  The compiler sometimes generates its own locals on top of what is in the source code. You can exclude these by using the RuleUtilities.IsCompilerGenerated helper method.

  This function shows how you could go about implementing this rule:

  public override ProblemCollection Check(Member member) { Method method = member as Method; if (method == null) return null; if (method.Instructions == null || method.Instructions.Length == 0) return null; LocalList locals = method.Instructions[0].Value as LocalList; if (locals == null) return null; for (int i = 0; i < locals.Length; i++) { Local local = locals[ i ]; if (local.Type != SystemTypes.Boolean) continue; if (RuleUtilities.IsCompilerGenerated(local)) continue; if (local.Name.Name.StartsWith("b")) continue; base.Problems.Add(new Problem(base.GetResolution(local.Name.Name), local)); } return Problems; }

  
  
  

• wissgtbob

  Note - I don't know if this is still valid in 1.35. Try it and see...
  
  

• Fernando D. Bozzo

  Thnx for the above code would try that out. But still one of the main problem remains unresolved as locals also inlcude functions return types

  so if I have a function as

  Private Function IsAddressNull(...) As Boolean

  the rule gives error as the function Name is not starting with b and type is boolean.

  How to solve this problem

  Thnx for all the help.... would be great if the above problem could also get resolved.

  
  
  
• FxCop Custom Rule: To check for variable name