Handle wrong/unsupported syntax in pred formulas

sandbox/grist/acl.py

@@ -164,8 +164,12 @@ def renamer(subject):
       return new_col_id
 
     new_acl_formula = predicate_formula.process_renames(formula, _ACLEntityCollector(), renamer)
-    rule_updates.append((rule_rec, {'aclFormula': new_acl_formula,
-                                    'aclFormulaParsed': parse_predicate_formula_json(new_acl_formula)}))
+    new_rule_record = {"aclFormula": new_acl_formula}
+    try:
+      new_rule_record["aclFormulaParsed"] = parse_predicate_formula_json(new_acl_formula)
+    except SyntaxError:
+      pass
+    rule_updates.append((rule_rec, new_rule_record)) 
 
   useractions.doBulkUpdateFromPairs('_grist_ACLResources', resource_updates)
   useractions.doBulkUpdateFromPairs('_grist_ACLRules', rule_updates)

sandbox/grist/dropdown_condition.py

@@ -55,9 +55,12 @@ def renamer(subject):
 
     new_dc_formula = predicate_formula.process_renames(dc_formula, _DCEntityCollector(), renamer)
 
-    # Parse the new dropdown condition formula.
-    widget_options["dropdownCondition"] = {"text": new_dc_formula,
-                                           "parsed": parse_predicate_formula_json(new_dc_formula)}
+    widget_options["dropdownCondition"] = {"text": new_dc_formula}
+    try:
+      # Parse the new dropdown condition formula if it is syntactically correct.
+      widget_options["dropdownCondition"]["parsed"] = parse_predicate_formula_json(new_dc_formula)
+    except SyntaxError:
+      pass
     updates.append((col, {"widgetOptions": json.dumps(widget_options)}))
 
   # Update the dropdown condition in the database.

sandbox/grist/predicate_formula.py

@@ -47,9 +47,12 @@ def parse_predicate_formula(formula):
         result = ['Comment', result, part[1][1:].strip()]
         break
     return result
-  except SyntaxError as err:
+  except SyntaxError as e:
     # In case of an error, include line and offset.
-    raise SyntaxError("%s on line %s col %s" % (err.args[0], err.lineno, err.offset))
+    raise SyntaxError("%s on line %s col %s" % (e.args[0], e.lineno, e.offset))
+  except ValueError as e:
+    # ValueError can be raised by TreeConverter.generic_visit when there is unsupported syntax.
+    raise SyntaxError(str(e))
 
 def parse_predicate_formula_json(formula):
   """
@@ -91,6 +94,9 @@ def process_renames(formula, collector, renamer):
   except SyntaxError:
     # Don't do anything to a syntactically wrong formula.
     return formula
+  except ValueError as e:
+    if str(e).startswith("Unsupported syntax"):
+      return formula
 
   for subject in collector.entities:
     new_name = renamer(subject)