util: only inspect error properties that are not visible otherwise

Inspecting errors results in duplicated information in case an error
is created with enumerable `name`, `message` or `stack` properties.
In that case, check if the output already contains that information
and prevent listing that property.

This reduces the noise as receiver.

PR-URL: https://github.com/nodejs/node/pull/32327
Reviewed-By: Anto Aravinth <anto.aravinth.cse@gmail.com>

1 files changed, 14 insertions, 2 deletions

diff --git a/lib/internal/util/inspect.js b/lib/internal/util/inspect.js
index a39779838a4..e25b599e8cc 100644
--- a/lib/internal/util/inspect.js
+++ b/lib/internal/util/inspect.js
@@ -890,7 +890,7 @@ function formatRaw(ctx, value, recurseTimes, typedArray) {
         return ctx.stylize(base, 'date');
       }
     } else if (isError(value)) {
-      base = formatError(value, constructor, tag, ctx);
+      base = formatError(value, constructor, tag, ctx, keys);
       if (keys.length === 0 && protoProps === undefined)
         return base;
     } else if (isAnyArrayBuffer(value)) {
@@ -1083,11 +1083,23 @@ function getFunctionBase(value, constructor, tag) {
   return base;
 }
 
-function formatError(err, constructor, tag, ctx) {
+function formatError(err, constructor, tag, ctx, keys) {
   const name = err.name != null ? String(err.name) : 'Error';
   let len = name.length;
   let stack = err.stack ? String(err.stack) : ErrorPrototypeToString(err);
 
+  // Do not "duplicate" error properties that are already included in the output
+  // otherwise.
+  if (!ctx.showHidden && keys.length !== 0) {
+    for (const name of ['name', 'message', 'stack']) {
+      const index = keys.indexOf(name);
+      // Only hide the property in case it's part of the original stack
+      if (index !== -1 && stack.includes(err[name])) {
+        keys.splice(index, 1);
+      }
+    }
+  }
+
   // A stack trace may contain arbitrary data. Only manipulate the output
   // for "regular errors" (errors that "look normal") for now.
   if (constructor === null ||