Extract lsp4j-agnostic code from lsp module

CONTRIBUTING.md

@@ -28,7 +28,9 @@ You'll find these in [`modules/lsp/src/test`](modules/lsp/src/test), and they ru
 
 This doesn't exercise the standard I/O interface of the server, but it's still a decent way to test the composition of all the modules with a filesystem directory ([`modules/lsp/src/test/resources/test-workspaces`](modules/lsp/src/test/resources/test-workspaces)).
 
-To run integration tests, run `lsp/test`.
+These are working without any external LSP library like lsp4j or Langoustine.
+
+To run integration tests, run `lsp-kernel/test`.
 
 ## Extension integration tests
 

build.sbt

@@ -195,23 +195,21 @@ lazy val core = module("core")
   )
 
 // LSP-like interfaces like CodeLensProvider, which are later adapted into actual lsp
+// but can be used in other, non-LSP contexts
 lazy val languageSupport = module("language-support")
   .dependsOn(core % "test->test;compile->compile", parser)
 
-// Adapters for language services to LSP, actual LSP server binding, entrypoint
-lazy val lsp = module("lsp")
+// LSP features that aren't specific to any given lsp library (lsp4j, langoustine)
+lazy val lspKernel = module("lsp-kernel")
   .settings(
     libraryDependencies ++= Seq(
-      "org.eclipse.lsp4j" % "org.eclipse.lsp4j" % "0.24.0",
       "io.circe" %% "circe-core" % "0.14.12",
       "org.http4s" %% "http4s-ember-client" % "0.23.30",
-      "org.http4s" %% "http4s-ember-server" % "0.23.30" % Test,
       ("io.get-coursier" % "coursier_2.13" % "2.1.24")
         .exclude("org.scala-lang.modules", "scala-collection-compat_2.13"),
       "org.typelevel" %% "cats-tagless-core" % "0.16.3",
+      "org.http4s" %% "http4s-ember-server" % "0.23.30" % Test,
     ).pipe(jsoniterFix),
-    buildInfoPackage := "playground.lsp.buildinfo",
-    buildInfoKeys ++= Seq(version, scalaBinaryVersion),
     (Test / test) := {
       (pluginCore / publishLocal).value
       (pluginSample / publishLocal).value
@@ -220,8 +218,20 @@ lazy val lsp = module("lsp")
     },
   )
   .enablePlugins(BuildInfoPlugin)
+  .settings(
+    buildInfoPackage := "playground.lsp.buildinfo",
+    buildInfoKeys ++= Seq(version, scalaBinaryVersion),
+  )
   .dependsOn(languageSupport)
 
+lazy val lsp = module("lsp")
+  .settings(
+    libraryDependencies ++= Seq(
+      "org.eclipse.lsp4j" % "org.eclipse.lsp4j" % "0.24.0"
+    )
+  )
+  .dependsOn(lspKernel)
+
 lazy val e2e = module("e2e")
   .enablePlugins(BuildInfoPlugin)
   .settings(
@@ -233,6 +243,7 @@ lazy val e2e = module("e2e")
           }
           // todo: replace with a full publishLocal before e2e in particular gets run (but not before tests run normally)
           .dependsOn(
+            lspKernel / publishLocal,
             lsp / publishLocal,
             languageSupport / publishLocal,
             core / publishLocal,
@@ -271,6 +282,7 @@ lazy val root = project
     parser,
     formatter,
     languageSupport,
+    lspKernel,
     lsp,
     protocol4s,
     pluginCore,

modules/language-support/src/main/scala/playground/language/CodeLensProvider.scala

@@ -71,6 +71,7 @@ case class CodeLens(
   command: Command,
 )
 
+// note: could be made a bit more type safe sometime
 case class Command(
   title: String,
   command: String,

modules/language-support/src/main/scala/playground/language/DiagnosticProvider.scala

@@ -22,8 +22,7 @@ import playground.types.*
 trait DiagnosticProvider[F[_]] {
 
   def getDiagnostics(
-    fileName: String,
-    documentText: String,
+    documentText: String
   ): List[CompilationError]
 
 }
@@ -37,8 +36,7 @@ object DiagnosticProvider {
     new DiagnosticProvider[F] {
 
       def getDiagnostics(
-        fileName: String,
-        documentText: String,
+        documentText: String
       ): List[CompilationError] = compilationErrors(documentText).fold(
         _.toList,
         parsed => runnerErrors(parsed),

modules/language-support/src/main/scala/playground/language/Feedback.scala

@@ -14,6 +14,7 @@ trait Feedback[F[_]] {
     msg: String
   ): F[Unit]
 
+  // custom smithyql/showOutputPanel notification in the client
   def showOutputPanel: F[Unit]
 
   def logOutput(

modules/language-support/src/test/scala/playground/language/DiagnosticProviderTests.scala

@@ -95,13 +95,13 @@ object DiagnosticProviderTests extends SimpleIOSuite {
   )
 
   pureTest("empty file - no diagnostics") {
-    assertNoDiff(provider.getDiagnostics("test.smithyql", ""), Nil)
+    assertNoDiff(provider.getDiagnostics(""), Nil)
   }
 
   pureTest("file doesn't parse at all") {
     val input = "horrendous <parsing mistake>"
     assertNoDiff(
-      provider.getDiagnostics("test.smithyql", input),
+      provider.getDiagnostics(input),
       List(
         CompilationError(
           err = CompilationErrorDetails.ParseError(expectationString = "{"),
@@ -117,7 +117,7 @@ object DiagnosticProviderTests extends SimpleIOSuite {
     val input = "AnyOp {}"
 
     assertNoDiff(
-      provider.getDiagnostics("test.smithyql", input),
+      provider.getDiagnostics(input),
       List(
         CompilationError(
           err = CompilationErrorDetails.AmbiguousService(
@@ -138,8 +138,7 @@ object DiagnosticProviderTests extends SimpleIOSuite {
 
     assertNoDiff(
       provider.getDiagnostics(
-        "test.smithyql",
-        input,
+        input
       ),
       List(
         CompilationError.error(
@@ -165,7 +164,7 @@ object DiagnosticProviderTests extends SimpleIOSuite {
         |noop#NoRunnerService.Noop {}""".stripMargin
 
     assertNoDiff(
-      provider.getDiagnostics("test.smithyql", input),
+      provider.getDiagnostics(input),
       List(
         CompilationError.info(
           err = CompilationErrorDetails.UnsupportedProtocols(
@@ -184,7 +183,7 @@ object DiagnosticProviderTests extends SimpleIOSuite {
       """playground.std#Random.NextUUID {}
         |playground.std#Clock.CurrentTimestamp {}""".stripMargin
 
-    assertNoDiff(provider.getDiagnostics("test.smithyql", input), Nil)
+    assertNoDiff(provider.getDiagnostics(input), Nil)
   }
 
 }

modules/lsp-kernel/src/main/scala/playground/lsp/LanguageClient.scala

@@ -0,0 +1,66 @@
+package playground.lsp
+
+import cats.FlatMap
+import cats.data.Kleisli
+import cats.syntax.all.*
+import cats.tagless.Derive
+import cats.tagless.FunctorK
+import cats.tagless.implicits.*
+import cats.~>
+import playground.language.Feedback
+
+trait LanguageClient[F[_]] extends Feedback[F] {
+
+  def configuration[A](
+    v: ConfigurationValue[A]
+  ): F[A]
+
+  def showMessage(
+    tpe: MessageType,
+    msg: String,
+  ): F[Unit]
+
+  def refreshDiagnostics: F[Unit]
+  def refreshCodeLenses: F[Unit]
+
+  def showInfoMessage(
+    msg: String
+  ): F[Unit] = showMessage(MessageType.Info, msg)
+
+  def showWarnMessage(
+    msg: String
+  ): F[Unit] = showMessage(MessageType.Warning, msg)
+
+  def showErrorMessage(
+    msg: String
+  ): F[Unit] = showMessage(MessageType.Error, msg)
+
+}
+
+object LanguageClient {
+
+  def apply[F[_]](
+    implicit F: LanguageClient[F]
+  ): LanguageClient[F] = F
+
+  implicit val functorK: FunctorK[LanguageClient] = Derive.functorK[LanguageClient]
+
+  def defer[F[_]: FlatMap](
+    fa: F[LanguageClient[F]]
+  ): LanguageClient[F] = Derive
+    .readerT[LanguageClient, F]
+    .mapK(new (Kleisli[F, LanguageClient[F], *] ~> F) {
+
+      def apply[A](
+        k: Kleisli[F, LanguageClient[F], A]
+      ): F[A] = fa.flatMap(k.run)
+
+    })
+
+}
+
+enum MessageType {
+  case Info, Warning, Error
+
+  def name: String = toString
+}