catch invalid regex in search

https://github.com/ankitects/anki/pull/652

qt/aqt/browser.py

@@ -171,7 +171,7 @@ class DataModel(QAbstractTableModel):
     def search(self, txt: str) -> None:
         self.beginReset()
         self.cards = []
-        invalid = False
+        error_message: Optional[str] = None
         try:
             ctx = SearchContext(search=txt)
             gui_hooks.browser_will_search(ctx)
@@ -180,13 +180,12 @@ class DataModel(QAbstractTableModel):
             gui_hooks.browser_did_search(ctx)
             self.cards = ctx.card_ids
         except Exception as e:
-            print("search failed:", e)
-            invalid = True
+            error_message = str(e)
         finally:
             self.endReset()
 
-        if invalid:
-            showWarning(_("Invalid search - please check for typing mistakes."))
+        if error_message:
+            showWarning(error_message)
 
     def reset(self):
         self.beginReset()

rslib/ftl/search.ftl

@@ -0,0 +1 @@
+search-invalid = Invalid search - please check for typing mistakes.

rslib/src/backend/mod.rs

@@ -145,6 +145,7 @@ fn anki_error_to_proto_error(err: AnkiError, i18n: &I18n) -> pb::BackendError {
         AnkiError::NotFound => V::NotFoundError(Empty {}),
         AnkiError::Existing => V::Exists(Empty {}),
         AnkiError::DeckIsFiltered => V::DeckIsFiltered(Empty {}),
+        AnkiError::SearchError(_) => V::InvalidInput(pb::Empty {}),
     };
 
     pb::BackendError {

rslib/src/err.rs

@@ -54,6 +54,9 @@ pub enum AnkiError {
 
     #[fail(display = "Unable to place item in/under a filtered deck.")]
     DeckIsFiltered,
+
+    #[fail(display = "Invalid search.")]
+    SearchError(Option<String>),
 }
 
 // error helpers
@@ -109,6 +112,13 @@ impl AnkiError {
                 DBErrorKind::Corrupt => info.clone(),
                 _ => format!("{:?}", self),
             },
+            AnkiError::SearchError(details) => {
+                if let Some(details) = details {
+                    details.to_owned()
+                } else {
+                    i18n.tr(TR::SearchInvalid).to_string()
+                }
+            }
             _ => format!("{:?}", self),
         }
     }
@@ -138,6 +148,11 @@ impl From<io::Error> for AnkiError {
 
 impl From<rusqlite::Error> for AnkiError {
     fn from(err: rusqlite::Error) -> Self {
+        if let rusqlite::Error::SqliteFailure(_error, Some(reason)) = &err {
+            if reason.contains("regex parse error") {
+                return AnkiError::SearchError(Some(reason.to_owned()));
+            }
+        }
         AnkiError::DBError {
             info: format!("{:?}", err),
             kind: DBErrorKind::Other,

rslib/src/search/parser.rs

@@ -119,8 +119,8 @@ pub(super) fn parse(input: &str) -> Result<Vec<Node>> {
         return Ok(vec![Node::Search(SearchNode::WholeCollection)]);
     }
 
-    let (_, nodes) = all_consuming(group_inner)(input)
-        .map_err(|_e| AnkiError::invalid_input("unable to parse search"))?;
+    let (_, nodes) =
+        all_consuming(group_inner)(input).map_err(|_e| AnkiError::SearchError(None))?;
 
     Ok(nodes)
 }