Merge pull request #1190 from stan-dev/bugfix/1189-pathfinder-diagnostics

Bugfix/1189 pathfinder diagnostics

Author: WardBrian

src/cmdstan/command.hpp

@@ -259,6 +259,10 @@ int command(int argc, const char *argv[]) {
         = get_arg_val<bool_argument>(*pathfinder_arg, "save_single_paths");
 
     if (num_paths == 1) {
+      if (!get_arg_val<string_argument>(parser, "output", "diagnostic_file")
+               .empty()) {
+        save_iterations = true;
+      }
       return_code = stan::services::pathfinder::pathfinder_lbfgs_single<
           false, stan::model::model_base>(
           model, *(init_contexts[0]), random_seed, id, init_radius,

src/test/interface/pathfinder_test.cpp

@@ -175,6 +175,22 @@ TEST_F(CmdStan, pathfinder_save_single_num_paths_1_diag_file_arg) {
   ASSERT_FALSE(file_exists(convert_model_path(output_single_json)));
 }
 
+TEST_F(CmdStan, pathfinder_save_single_num_paths_0_diag_file_arg) {
+  std::stringstream ss;
+  ss << convert_model_path(multi_normal_model)
+     << " output refresh=0 file=" << convert_model_path(arg_output)
+     << " diagnostic_file=" << convert_model_path(arg_diags)
+     << " method=pathfinder"
+     << " num_paths=1 save_single_paths=0";
+  run_command_output out = run_command(ss.str());
+  ASSERT_FALSE(out.hasError);
+  ASSERT_TRUE(file_exists(convert_model_path(output_csv)));
+  ASSERT_TRUE(file_exists(convert_model_path(output_diags)));
+  ASSERT_FALSE(file_exists(convert_model_path(output_json)));
+  ASSERT_FALSE(file_exists(convert_model_path(output_single_csv)));
+  ASSERT_FALSE(file_exists(convert_model_path(output_single_json)));
+}
+
 TEST_F(CmdStan, pathfinder_num_paths_8) {
   std::stringstream ss;
   ss << convert_model_path(multi_normal_model)