fix: prevent stuck "Loading..." hover by timing out after 5s

Author: sebthom

org.eclipse.lsp4e/src/org/eclipse/lsp4e/operations/hover/LSPTextHover.java

@@ -65,6 +65,7 @@
 public class LSPTextHover implements ITextHover, ITextHoverExtension, ITextHoverExtension2 {
 
 	private static final int GET_HOVER_REGION_TIMEOUT_MS = 100;
+	private static final int GET_HOVER_CONTENT_TIMEOUT_SECONDS = 5;
 
 	private @Nullable IRegion lastRegion;
 	private @Nullable ITextViewer lastViewer;
@@ -111,7 +112,9 @@ public class LSPTextHover implements ITextHover, ITextHoverExtension, ITextHover
 			} else {
 				return null;
 			}
-		});
+		})
+				// Ensure the placeholder is not stuck if LS never replies
+				.completeOnTimeout(null, GET_HOVER_CONTENT_TIMEOUT_SECONDS, TimeUnit.SECONDS);
 	}
 
 	protected static @Nullable String getHoverString(Hover hover) {