ghdl-ls: Fix exceptions crashing language server

Previously, the language server crashed on any exceptions raised by the
handler methods. Catching and logging these exceptions while notify the
user about the error results in a much better user experience.

This fixes #1410

1 files changed, 14 insertions, 1 deletions

diff --git a/python/vhdl_langserver/lsp.py b/python/vhdl_langserver/lsp.py
index 983b3005e..8f5a98e5e 100644
--- a/python/vhdl_langserver/lsp.py
+++ b/python/vhdl_langserver/lsp.py
@@ -113,7 +113,20 @@ class LanguageProtocolServer(object):
         if fmethod:
             if params is None:
                 params = {}
-            response = fmethod(**params)
+            try:
+                response = fmethod(**params)
+            except Exception as e:
+                log.exception(
+                    "Caught exception while handling %s with params %s:",
+                    method, params
+                )
+                self.show_message(
+                    MessageType.Error,
+                    ("Caught exception while handling {}, " +
+                     "see VHDL language server output for details.").format(
+                        method)
+                )
+                response = None
             if tid is None:
                 # If this was just a notification, discard it
                 return None