We had both a property and a method returning the same thing. This
unifies to just the method.

With TestWorkspace we were creating text buffers for all types of
documents up front, and by default opening all buffers in the workspace.
This was problematic because if we're creating text buffers we should
be ensuring the text buffer's options for using tabs and spaces matches
the Workspace options, but the workspace sometimes wasn't available
at those times. This is also unnecessarily expensive if you have test
projects that aren't doing anything with editor experiences at all.

Also, a complicated "create a separate document in the TestWorkspace for
the cursor" was removed in favor of more direct code that just creates
a buffer. Creating an entire TestDocument was funky since the document
was never actually part of the workspace -- this revealed that it didn't
seem we were ever disposing the views created.

The "languageName" parameter to CreateProjectionBuffer was removed: it
didn't logically make sense (the projection buffer created isn't in
a Workspace, so it has no language name), but also wasn't being used
for anything else.

The overloads sometimes had exportProvider first and sometimes second.
This was because if you always had it first and content type is passed
as a string, you have ambiguity of how to handle the params array.
Just passing in stuff explicitly makes this easier.

Also replace a hand-written implementation of string.Join with
string.Join.

Makes it easier to figure out when just one side is failing.

This is implemented by adding metadata to exports of
IDocumentOptionsProviderFactories that specify the ordering like any
other provider. Although I would love to simplify this by simply
removing the factories entirely by simply having the Workspace
constructor directly add the instances, Visual Studio for Mac is also
exporting these so we'll maintain compat for now.

I expect that IOrderableMetadata existed back from a time where we
were working with both MEFv1 interface metadata views and MEFv2
concrete type views. Nothing today needs it anymore, so we can just
delete it.

If we both had a document-specific option provided and also tried
to change the value, we'd end up throwing an exception.

This adds a convenience overload where WithChangedOption can be more
easily used with a PerLanguageOption, but also returns a strongly
typed DocumentOptionSet so you don't lose the distinction.

These no longer apply.

There appeared to be one bug: if a document was opened that had a null
file path, there was a risk that we would crash because we would be
passing that around to the editor API in the legacy case.

Handle intellicode star in display text prefix

Semantic model assert

Link to http://sourceroslyn.io

Performance fix in analyzer driver for CFG based analyzers

Re-use semantic model when attempting to compute suppress message att…

(cherry picked from commit 1170c94f37305d39faee86f04c724caf588fc9f5)

Remove shortcircuit of status query for commands with handlers.

Instead of intercepting QueryStatus in AbstractOleCommandTarget we
will allow the request to bubble up for commands with command handlers.

Add nullable annotations to IDE code (part 2)

Fix SourceText.GetChanges exception on merging certain changes

ProjectExternalErrorReporter: Avoid subscribing to solution build events multiple times and leaking the object (#39389)

* Add FSharpProjectExternalErrorReporterFactory

* ProjectExternalErrorReporter: Avoid subscribing to solution build events multiple times and leaking the object

* Update F# shim

Use lifted operator in generated Equals if the underlying type's operator would have been used

* async -> asynchronous
* Fix up error messages for await using declarations in langver < 8.0
* Use CSharpTestBase.IAsyncDisposableDefinition for interfaces

We expose public APIs on IOperation related analysis contexts to fetch ControlFlowGraph for the operation block. Additionally, the analyzer driver caches the CFGs for operation block (when first requested by some flow based analyzer) to allow sharing CFGs between flow based analyzers. However, we were holding onto these for the entire lifetime of the compilation. This change fixes that by removing the CFG entry once a particular operation block has been fully analyzed.

Fixes VSFeedback issue [#998181](https://dev.azure.com/devdiv/DevDiv/_workitems/edit/998181)

Currently implementation always creates a new semantic model for decoding local suppress message attributes (applied to each symbol). This change attempts to re-use the cached semantic models held by the analyzer driver to avoid rebinding cost.
Fixes VSFeedback issue [#973445](https://dev.azure.com/devdiv/DevDiv/_workitems/edit/973445)

* EnC: Compare document content before performing IO while stepping

* Feedback

Enable detection and addition of solution level .editorconfig as solu…

Use ConstructWithNullability in InferTypeInAwaitExpression since the inferred type may include nullable information (#39335)

The inferred type may include nullability information, and will fail to be recognized as a symbol without using the correct construct call.

Fixes #39333