Fill target errors with nans for evaluate

sdk/evaluation/azure-ai-evaluation/azure/ai/evaluation/_evaluate/_evaluate.py

@@ -611,13 +611,32 @@ def _apply_target_to_data(
             category=ErrorCategory.FAILED_EXECUTION,
             blame=ErrorBlame.USER_ERROR,
         )
+
+    # Log a warning if some rows failed
+    failed_lines = run_summary.get("failed_lines", 0)
+    completed_lines = run_summary["completed_lines"]
+    total_lines = failed_lines + completed_lines
+
+    if failed_lines > 0:
+        LOGGER.warning(
+            f"Target function completed {completed_lines} out of {total_lines} rows. "
+            f"{failed_lines} rows failed and will be filled with NaN values."
+        )
+
     # Remove input and output prefix
     generated_columns = {
         col[len(Prefixes.OUTPUTS) :] for col in target_output.columns if col.startswith(Prefixes.OUTPUTS)
     }
     # Sort output by line numbers
     target_output.set_index(f"inputs.{LINE_NUMBER}", inplace=True)
     target_output.sort_index(inplace=True)
+
+    initial_data_with_line_numbers = initial_data.copy()
+    initial_data_with_line_numbers[LINE_NUMBER] = range(len(initial_data))
+
+    complete_index = initial_data_with_line_numbers[LINE_NUMBER]
+    target_output = target_output.reindex(complete_index)
+
     target_output.reset_index(inplace=True, drop=False)
     # target_output contains only input columns, taken by function,
     # so we need to concatenate it to the input data frame.
@@ -626,8 +645,8 @@ def _apply_target_to_data(
     # Rename outputs columns to __outputs
     rename_dict = {col: col.replace(Prefixes.OUTPUTS, Prefixes.TSG_OUTPUTS) for col in target_output.columns}
     target_output.rename(columns=rename_dict, inplace=True)
-    # Concatenate output to input
-    target_output = pd.concat([target_output, initial_data], axis=1)
+    # Concatenate output to input - now both dataframes have the same number of rows
+    target_output = pd.concat([initial_data, target_output], axis=1)
 
     return target_output, generated_columns, run