URL can in fact store URIs, it just doesn't have a very nice API to
interact with them. As long as we only operate on absoluteString, we
should be fine though. So instead of implementing the logic for
detecting file URLs ourselves, we can just use a URL as storage for
DocumentURI.
According to the LSP specification, arbitrary URIs can be used as
document identifiers. Instead of internally assuming that all URIs are
URLs, use a DocumentURI enum to represent URIs. These can either be file
URLs or other URIs whose value as treated as an opaque string.
We will be able to split the LSP modules off later. These LSP modules
will provide the ability to write custom LSP servers and clients in
Swift. The sourcekit-lsp repository will build on top of this new
package to provide an LSP implementation that creates a language server
for Swift and C-based-languages.
`SourceKitServer` now talks to the `SwiftLanguageServer` and
`ClangLanguageServerShim` directly through the `ToolchainLanguageServer`
protocol.
Each individual `ToolchainLanguageServer` manages its own threading.
Change-Id: I77aa5468f1486bd4e6e6fdb732c6a051ee05c6d1
While we ideally could maintain diagnostics state for closed documents
as the LSP specification encourages, since we have no way to do that
today, it's better to throw out diagnostics for closed documents so that
they do not sit around stale. We do not send a publishDiagnostics
though, so the editor can maintain the list of diagnostics if desired,
but when we reopen the document we can provide completely fresh data.
This lets us use the `Range<Position>` without manually converting back
and forth in the majority of cases. See the note on HoverResponse for
the behaviour with Optional that makes us have to provide a custom
Codable implementation in two places that used to be synthesized.
Introduce a `BuildSystemDelegate` to handle notifications from the build system
* `SourceKitServer` is the main delegate to process these notifications
* Currently limited to changes in `FileBuildSettings`
* Delegate informs the `BuildSystem` of files to watch via `registerChangeWatching(for: URL)` and `unregisterChangeWatching(for: URL)`
* In the future we could have more integration for handling changes in dependencies
Handling changes in `FileBuildSettings`
* `SourceKitServer` sends notifications to the internal LSPs informing them of any opened documents that have changes in their compiler flags
* For clangd, we send a notification to update the compilation database
* For SourceKit/sourcekitd we must close and reopen the file to force a new AST with the new compiler flags
Sourcekitd returns parse diagnostics immediately after edits, but we do
not want to clear the semantic diagnostics until we have semantic level
diagnostics from after the edit.