HOWTO: Get the conditional compile symbols defined in the project for a source file (ITextView) in a Visual Studio Extension

Monday, August 31, 2015
One of the things I ran into when parsing with Roslyn in Stay Frosty was that #if / #endif blocks were treated as strictly in the parser as they are in Visual Studio (well, that should be obvious, it's the parser used by VS, isn't it?). That meant code that was riddled with preprocessor rules wasn't being parsed properly because it didn't know what I had defined.
Fortunately the Visual Studio SDK provides a way at these values. Unfortunately, it's not as straight forward as I would have liked.
Conditionals given an ITextView
Here's a quick extension method I whipped up to pull the "defines" out of the project file given an ITextView/IWpfTextView.
private static IEnumerable<string> Conditionals([NotNull] this ITextView textView)
            if (textView == null) throw new ArgumentNullException(nameof(textView));

            // Get the text document from the text buffer (if it has one)
            ITextDocument textDocument;
            if (textView.TextBuffer.Properties.TryGetProperty(typeof (ITextDocument), out textDocument))
                yield break;

            var componentModel = ServiceProvider.GlobalProvider.GetService(typeof(SComponentModel)) as IComponentModel;

            // Get the VsServiceProvider
            var vsServiceProvider = componentModel?.DefaultExportProvider?.GetExportedValue<SVsServiceProvider>();
            if (vsServiceProvider == null) yield break;

            // Get the DTE ...
            var dte = (DTE) vsServiceProvider.GetService(typeof (DTE));

            ProjectItem projectItem = dte.Solution.FindProjectItem(textDocument.FilePath);
            Configuration activeConfiguration = projectItem?.ContainingProject?.ConfigurationManager?.ActiveConfiguration;

            var defineConstants = activeConfiguration?.Properties?.Item("DefineConstants")?.Value as string;

            if (defineConstants == null)
                yield break;
            // DefineConstants entries are listed semicolon and comma delimiated, so we need to split on both.
            string[] constantSplit = defineConstants.Split(new[] { ';', ',' }, StringSplitOptions.RemoveEmptyEntries);

            foreach (var item in constantSplit)
                yield return item.Trim(); // They can contain whitespace on either end, so we'll strip 'em.
Of course, you could get some of those services via an Export and eliminate the GetService / GetExported value calls, but I thought I'd include them since I don't know what you've decided to get from MEF.
Have a lot of fun!

Stay Frosty Visual Studio Extension - Method Block Highlighter, Text Clarity, Background Images and a lot more...

Sunday, August 30, 2015
Updated 9/4/2015 9:00 PM Published to the Extension Gallery (links at the bottom). Thanks for the feedback!
For the most updated information, visit the release page

It's hard to believe but I've been working on this extension for almost a year. That's what happens when you only have a few hours every weekend and the occasional evening to work on a personal project. It started out with a simple desire to add a chiseled effect to the text displayed in Visual Studio. I used to get horrible migraine headaches and that little effect made text visibility at low contrast much better without having to change my syntax highlighting rules. A little later I decided I hated being tied to my multi-monitor setup just to be productive when writing software. So I started working exclusively from my laptop screen, a nice 1920x1080, but still not as nice as having a few portrait 1080P displays and a primary 2K, but with a little bit of a change in how I worked (mostly just getting used to some features I never had needed with unlimited real estate), I was easily as productive on my laptop screen. The advantages of changing scenes means I can work when I feel an inspiration; no more having to tuck myself into a room.
Most of the features of Frosty were designed with two purposes in mind: (1) Make working with code in limited screen real estate easier and (2) Make my environment prettier. Both are quite subjective and I don't expect everyone to agree with my decisions ... in fact, I wrote this for me, so if I'm the only user, I'll still be happy!
Method Blocks
Methods are highlighted with configurable colors, Static, Instance and Constructors. I decided against making those colors configurable in Fonts and Colors because I wanted to be able to control alpha on each, so I've done it via its own Options panel with a color picker. Sure, methods should be small enough to easily visually parse the beginning and end, but we're not always given the privilege of modifying code we've written. By default, constructors are bright, instance methods are dim and static methods are somewhere in between. I'm always looking to get back to a constructor, so I made it stand out a bit. In a God Object or a method that does too much (that, of course, *I* didn't write! :o) ...), finding important bits is easy.
Method Signatures
When the method signature scrolls off the top of the display, it shows up on the left hand side next to the box around the method. Sure, that's available from the drop-down at the top, but my caret isn't always in the method I want to know about. Now it's right in front of me.
Text Rendering
Text rendering in the editor window is also configurable. Much like the great extension, TextSharp, except I only apply the effect to the text editor window (no reason for this other than that I didn't need the rest). You can enable ClearType or kill it, along with other things WPF allows you to tweak that Visual Studio doesn't give you direct control over.
Chiseled Text Effect
It's off by default. This was the original feature that I wanted, but getting it working turned into a several month long adventure with HLSL. Unfortunately, it doesn't render properly in Visual Studio 2015 without Hardware Rendering enabled. The effect is touchy. Colors need to have a bit of grey in them to render and different colors render slightly higher or lower on the baseline. It's a bug I intend to fix, but for now consider it quite "alpha" in nature. That's life!
Go to "Stay Frosty" in "Tools|Options". You'll find it *highly* configurable. I like ultimate control over my environment so I tried to leave nothing out as far as customization. Maybe you don't like the features I've implemented? Turn 'em off or change them! Sure, software should be opinionated,... except when its users are developers.
I'm not ready to release the source code quite yet, but I will be. The extension is licensed under the Apache 2.0 license. I had to learn quite a bit about Visual Studio Extension development over the last few months and I'm hoping that my experiences with it will help others, so I'm separating out parts into their own projects that can be used by others as utility libraries. Right now, time is keeping me from completing that part, plus I'd like to get a little more feedback from testing in the wild before I throw that out there.
At the moment Frosty supports Visual Studio 2013 and Visual Studio 2015. I'm using the awesome NRefactory library for code parsing in Visual Studio 2013. The 2015 version, of course, uses Roslyn and as a result performs a bit better than the 2013 version. Since I started with 2013, I didn't want to abandon that work and all of the folks who are stuck on the old version.
Caveats - It's Beta
It's beta. If you run into difficulties, please let me know at matthew dot dippel at google's public e-mail service. I'd love to get it right and working. If you want to help out, I'll have the code out on GitHub soon!
There's (at least) one bug. The signatures don't always disappear from the left hand side when the top of the method becomes visible again when scrolling up. And it does use some additional resources when parsing code on Visual Studio 2013 -- it shouldn't get in the way too much on a decent machine (it performs well on my Core i5)
Updates from Initial Feedback
If you use ReSharper (I do!), you can enable their syntax highlighting rules (disabled by default, enable them in options).
You can now enable the Method Signatures to display regardless of whether or not the method signature is scrolled off screen (disabled by default).
Abstract methods are no longer bordered.
Two libraries were removed in favor of the PresentationFramework equivalents.
The error that some were seeing when visiting the options page might be fixed. (I'm not seeing this on my machines)
If ReSharper or the User Classes/Enums/etc Fonts and Colors option is missing, we'll use Identifiers instead of Plain Text.
Fixed an exception that occasionally happened on file load where the width of the adornment would be calculated to a negative number.
Fixed the caching of method signatures so they wouldn't have to be re-created every time they were drawn.

Download the Visual Studio 2015 Edition
Download the Visual Studio 2013 Edition