(core) Allow assistant to evaluate current formula

Summary:
Replaces https://phab.getgrist.com/D3940, particularly to avoid doing potentially unwanted things automatically.

Adds optional fields `evaluateCurrentFormula?: boolean; rowId?: number` to `FormulaAssistanceContext` (part of `AssistanceRequest`). When `evaluateCurrentFormula` is `true`, calls a new function `evaluate_formula` in the sandbox which computes the existing formula in the column (regardless of anything the AI may have suggested) and uses that to generate an additional system message which is added before the user's message. In theory this could be used in an interface where users ask why a formula doesn't work, including possibly a formula suggested by the AI. For now, it's only used in `runCompletion_impl.ts` for experimenting.

Also cleaned up a bit, removing `_chatMode` which is always `true` now, and uses of `regenerate` which is always `false`.

Test Plan: Updated `runCompletion_impl` to optionally use the new feature, in which case it now scores 51/68 instead of 49/68.

Reviewers: paulfitz

Reviewed By: paulfitz

Differential Revision: https://phab.getgrist.com/D3970

sandbox/grist/engine.py

@@ -20,6 +20,7 @@ from sortedcontainers import SortedSet
 import acl
 import actions
 import action_obj
+from attribute_recorder import AttributeRecorder
 from autocomplete_context import AutocompleteContext, lookup_autocomplete_options, eval_suggestion
 from codebuilder import DOLLAR_REGEX
 import depend
@@ -694,22 +695,27 @@ class Engine(object):
     not recomputing the whole column and dependent columns as well. So it recomputes the formula
     for this cell and returns error message with details.
     """
+    result = self.get_formula_value(table_id, col_id, row_id)
+    table = self.tables[table_id]
+    col = table.get_column(col_id)
+    # If the error is gone for a trigger formula
+    if col.has_formula() and not col.is_formula():
+      if not isinstance(result, objtypes.RaisedException):
+        # Get the error stored in the cell
+        # and change it to show to the user that no traceback is available
+        error_in_cell = objtypes.decode_object(col.raw_get(row_id))
+        assert isinstance(error_in_cell, objtypes.RaisedException)
+        return error_in_cell.no_traceback()
+    return result
+
+  def get_formula_value(self, table_id, col_id, row_id, record_attributes=None):
     table = self.tables[table_id]
     col = table.get_column(col_id)
     checkpoint = self._get_undo_checkpoint()
     # Makes calls to REQUEST synchronous, since raising a RequestingError can't work here.
     self._sync_request = True
     try:
-      result = self._recompute_one_cell(table, col, row_id)
-      # If the error is gone for a trigger formula
-      if col.has_formula() and not col.is_formula():
-        if not isinstance(result, objtypes.RaisedException):
-          # Get the error stored in the cell
-          # and change it to show to the user that no traceback is available
-          error_in_cell = objtypes.decode_object(col.raw_get(row_id))
-          assert isinstance(error_in_cell, objtypes.RaisedException)
-          return error_in_cell.no_traceback()
-      return result
+      return self._recompute_one_cell(table, col, row_id, record_attributes=record_attributes)
     finally:
       # It is possible for formula evaluation to have side-effects that produce DocActions (e.g.
       # lookupOrAddDerived() creates those). In case of get_formula_error(), these aren't fully
@@ -920,7 +926,7 @@ class Engine(object):
 
     raise RequestingError()
 
-  def _recompute_one_cell(self, table, col, row_id, cycle=False, node=None):
+  def _recompute_one_cell(self, table, col, row_id, cycle=False, node=None, record_attributes=None):
     """
     Recomputes an one formula cell and returns a value.
     The value can be:
@@ -939,6 +945,11 @@ class Engine(object):
 
     checkpoint = self._get_undo_checkpoint()
     record = table.Record(row_id, table._identity_relation)
+    if record_attributes is not None:
+      assert isinstance(record_attributes, dict)
+      assert col.is_formula()
+      assert not cycle
+      record = AttributeRecorder(record, "rec", record_attributes)
     value = None
     try:
       if cycle: