From 5ff18a9b27c1f79ad6385371684fd35c4f930bb7 Mon Sep 17 00:00:00 2001
From: Angela Chen <chenangela@google.com>
Date: Fri, 11 Aug 2023 01:54:43 -0400
Subject: [PATCH] Add error for invalid config file name

---
 src/ppx/command_line_parser.cpp | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/src/ppx/command_line_parser.cpp b/src/ppx/command_line_parser.cpp
index 8e68ed039..9e768951f 100644
--- a/src/ppx/command_line_parser.cpp
+++ b/src/ppx/command_line_parser.cpp
@@ -151,7 +151,10 @@ std::optional<CommandLineParser::ParsingError> CommandLineParser::Parse(int argc
     std::vector<std::string> configJsonPaths;
     configJsonPaths = mOpts.GetOptionValueOrDefault("config-json-path", configJsonPaths);
     for (const auto& jsonPath : configJsonPaths) {
-        std::ifstream  f(jsonPath);
+        std::ifstream f(jsonPath);
+        if (f.fail()) {
+            return "Invalid --config-json-path: " + jsonPath;
+        }
         nlohmann::json data = nlohmann::json::parse(f);
         if (auto error = AddJsonOptions(data)) {
             return error;