Add some tests trying to expose #1585

src/extension-test/unit/cursor-doc/token-cursor-test.ts

@@ -386,7 +386,7 @@ describe('Token Cursor', () => {
             cursor.forwardList();
             expect(cursor.offsetStart).toBe(b.selectionLeft);
         });
-        it('Does not move when unbalanced from extra opens', () => {
+        it('Does not move when at start of unbalanced list', () => {
             // https://github.com/BetterThanTomorrow/calva/issues/1573
             // https://github.com/BetterThanTomorrow/calva/commit/d77359fcea16bc052ab829853d5711434330a375
             const a = docFromTextNotation('([|');
@@ -396,6 +396,14 @@ describe('Token Cursor', () => {
             expect(result).toBe(false);
             expect(cursor.offsetStart).toBe(b.selectionLeft);
         });
+        it('Moves to stary of unbalanced list', () => {
+            const a = docFromTextNotation('(let [a| a');
+            const b = docFromTextNotation('(let [|a a');
+            const cursor: LispTokenCursor = a.getTokenCursor(a.selectionLeft);
+            const result = cursor.backwardList();
+            expect(result).toBe(true);
+            expect(cursor.offsetStart).toBe(b.selectionLeft);
+        });
         it('Finds the list start when unbalanced from extra closes outside the current list', () => {
             const a = docFromTextNotation('([]|))');
             const b = docFromTextNotation('(|[]))');

test-data/calva-252-hang.clj

@@ -0,0 +1,15 @@
+;; https://github.com/BetterThanTomorrow/calva/issues/1585
+
+;; Confirm that structural editing works here:
+
+(defn foo [{:keys [bar]}] 'baz)
+
+;; Here a repro that works for at least one user:
+;; Place the cursor to the right of the closing square bracket and press delete
+;; until the text is `(let [a] a)`. Then highlight the select the closing square
+;; bracket and press delete. Structural editing and rainbow parens is now broken.
+
+(let [a "123"] a)
+
+(let [a] a)
+