Complex branches are reported incorrectly

[SteveGilham]

This is the same code as for OpenCover issue 819

The only branch point reported for this line is

                <BranchPoint vc="9" upsid="198" ordinal="3" path="" offset="3" offsetend="3" sl="198" fileid="4" />

when there are five visible (seven in the underlying IL) ways of proceeding

I note in passing that the offset values here are not the IL offset values of the branch and its terminus as generated by opencover.

[SteveGilham]

Actually, it seems that switch instructions are not being recognised as branches, either as in

    public enum Scope
    {
        None = 0,
        Some,
        Many
    }
...
            switch (arg)
            {
                case Scope.None: ...
                case Scope.Some: ...
                case Scope.Many: ...
            }

or in F# match expressions like

type internal FilterClass =
  | File of Regex
  | Assembly of Regex
  | Module of Regex
  | Type of Regex
  | Method of Regex
  | Attribute of Regex
...
    match filter with
    | File name -> ...
    | Assembly name -> ...
    | Module name -> ...
    | Type name -> ...
    | Method name -> ...
    | Attribute name -> ...

[hunterjm]

Branch enhancements are in #73. It uses the same logic OpenCover uses for determining branches, so it will still only report 5 vs the 7, but 5 > 1. It also fixes the switches not showing as branches.

[SteveGilham]

OpenCover does report 5 branches in this case, but they're the wrong 5. The decompiled code looks like

			if (!(message is Message.Item)) <= not this
			{
				if (!(message is Message.Finish)) <= nor this
				{
                                     ...
                                     return;
				}
				Message.Finish finish = (Message.Finish)msg;
				switch (finish.item1.Tag) <=but  5 paths from this 
				{
				default: // Cases 0 and 1
                                     ...
                                     return;
				case 2: // Pause
                                     ...
                                     return;
				case 3: // Resume
                                     ...
                                     return;
				}
			}
                        ...
                        return;

and it detects cases 0, 1 and out-of-band as distinct routes to the default case (see OpenCover issue #786) , and doesn't detect the if branches.

[MarcoRossignoli]

@SteveGilham this issue is very old, is this issue still present? Can you give it a try with last version?

[SteveGilham]

Between changes in the compiler and the tooling, this issue no longer reproduces. The example code was like this
Coverlet79.zip

Now the decompiled code looks almost the same (default shown last in the decompilation)

	if (!(msg is Message.Item)) // offset = 10
	{
		if (!(msg is Message.Finish))  // offset = 18
		{
			...
			return;
		}
		Message.Finish finish = (Message.Finish)msg;
		switch (finish.item1.Tag) // offset = 58
		{
		case 1: // Pause
			...
			return;
		case 2: // Resume
			...
			return;
		default:  
			...
			return;
		}
	}
	...
	return;

and 8 branches are shown

                <BranchPoint vc="0" uspid="18" ordinal="0" path="0" offset="10" offsetend="12" sl="18" fileid="2" />
                <BranchPoint vc="0" uspid="18" ordinal="2" path="0" offset="18" offsetend="20" sl="18" fileid="2" />
                <BranchPoint vc="1" uspid="18" ordinal="1" path="1" offset="10" offsetend="29" sl="18" fileid="2" />
                <BranchPoint vc="0" uspid="18" ordinal="3" path="1" offset="18" offsetend="38" sl="18" fileid="2" />
                <BranchPoint vc="0" uspid="18" ordinal="6" path="2" offset="58" offsetend="138" sl="18" fileid="2" />
                <BranchPoint vc="0" uspid="18" ordinal="7" path="3" offset="58" offsetend="156" sl="18" fileid="2" />
                <BranchPoint vc="0" uspid="18" ordinal="4" path="0" offset="58" offsetend="174" sl="18" fileid="2" />
                <BranchPoint vc="0" uspid="18" ordinal="5" path="1" offset="58" offsetend="174" sl="18" fileid="2" />

2 per if, 3 switch cases and path 0 being the unobtainable "do not jump" case

[MarcoRossignoli]

Thx for testing.