Add convenience properties for errors/warnings in test fixture

Author: fwcd

server/src/test/kotlin/org/javacs/kt/DiagnosticTest.kt

@@ -15,8 +15,8 @@ class DiagnosticTest : SingleFileTestFixture("diagnostic", "Diagnostics.kt") {
         languageServer.textDocumentService.debounceLint.waitForPendingTask()
 
         assertThat(diagnostics, hasSize(2))
-        assertThat(diagnostics.filter { it.severity == DiagnosticSeverity.Warning }, hasSize(1))
-        assertThat(diagnostics.filter { it.severity == DiagnosticSeverity.Error }, hasSize(1))
+        assertThat(errors, hasSize(1))
+        assertThat(warnings, hasSize(1))
     }
 
     @Test fun `only lint once for many edits in a short period`() {

server/src/test/kotlin/org/javacs/kt/LanguageServerTestFixture.kt

@@ -11,7 +11,12 @@ import java.util.concurrent.CompletableFuture
 abstract class LanguageServerTestFixture(relativeWorkspaceRoot: String) : LanguageClient {
     val workspaceRoot = absoluteWorkspaceRoot(relativeWorkspaceRoot)
     val languageServer = createLanguageServer()
+
     val diagnostics = mutableListOf<Diagnostic>()
+    val errors: List<Diagnostic>
+        get() = diagnostics.filter { it.severity == DiagnosticSeverity.Error }
+    val warnings: List<Diagnostic>
+        get() = diagnostics.filter { it.severity == DiagnosticSeverity.Warning }
 
     fun absoluteWorkspaceRoot(relativeWorkspaceRoot: String): Path {
         val testResources = testResourcesRoot()