From af3ff83dc41c7736b7e57f2a02fd94ac03b76a4c Mon Sep 17 00:00:00 2001
From: Alexander Fenster <fenster@google.com>
Date: Mon, 15 Jan 2024 22:43:29 -0800
Subject: [PATCH] fix: report missing import properly in loadSync (#1960)

---
 src/root.js                |  4 ++--
 tests/api_root.js          | 23 +++++++++++++++++++++++
 tests/data/badimport.proto |  7 +++++++
 3 files changed, 32 insertions(+), 2 deletions(-)
 create mode 100644 tests/data/badimport.proto

diff --git a/src/root.js b/src/root.js
index 9441a7fc3..2776f96e4 100644
--- a/src/root.js
+++ b/src/root.js
@@ -98,10 +98,10 @@ Root.prototype.load = function load(filename, options, callback) {
         /* istanbul ignore if */
         if (!callback)
             return;
-        var cb = callback;
-        callback = null;
         if (sync)
             throw err;
+        var cb = callback;
+        callback = null;
         cb(err, root);
     }
 
diff --git a/tests/api_root.js b/tests/api_root.js
index 6e9814ddb..9125d3aa8 100644
--- a/tests/api_root.js
+++ b/tests/api_root.js
@@ -67,6 +67,29 @@ tape.test("reflected roots", function(test) {
         });
     });
 
+    test.test(test.name + " - missing import", function(test) {
+        var root = new Root();
+        test.plan(2);
+        root.load("tests/data/badimport.proto", function(err) {
+            test.ok(err, "should return an error when an imported file does not exist");
+            test.match(err.toString(), /nonexistent\.proto/, "should mention the file name which was not found");
+            test.end();
+        });
+    });
+
+    test.test(test.name + " - missing import, sync load", function(test) {
+        var root = new Root();
+        test.plan(2);
+        try {
+            root.loadSync("tests/data/badimport.proto");
+            root.resolveAll();
+        } catch (err) {
+            test.ok(err, "should return an error when an imported file does not exist");
+            test.match(err.toString(), /nonexistent\.proto/, "should mention the file name which was not found");
+        }
+        test.end();
+    });
+
     test.test(test.name + " - skipped", function(test) {
         var root = new Root();
         root.resolvePath = function() {
diff --git a/tests/data/badimport.proto b/tests/data/badimport.proto
new file mode 100644
index 000000000..f11caaf6b
--- /dev/null
+++ b/tests/data/badimport.proto
@@ -0,0 +1,7 @@
+syntax = "proto3";
+
+import "nonexistent.proto";
+
+message Message {
+  NonExistent field = 1;
+}