Defend against losing the first exception's message when Exception.ToString() throws

AArnott · AArnott · commit 5e7a00ed2441 · 2021-09-22T20:48:49.000-06:00
diff --git a/src/nbgv/Program.cs b/src/nbgv/Program.cs
@@ -215,9 +215,23 @@ private static Parser BuildCommandLine()
                         }
                     }
                 }, (MiddlewareOrder)(-3000)) // MiddlewareOrderInternal.ExceptionHandler so [parse] directive is accurate.
+                .UseExceptionHandler((ex, context) => PrintException(ex, context))
                 .Build();
         }
 
+        private static void PrintException(Exception ex, InvocationContext context)
+        {
+            try
+            {
+                Console.Error.WriteLine("Unhandled exception: {0}", ex);
+            }
+            catch (Exception ex2)
+            {
+                Console.Error.WriteLine("Unhandled exception: {0}", ex.Message);
+                Console.Error.WriteLine("Unhandled exception while trying to print string version of the above exception: {0}", ex2);
+            }
+        }
+
         private static int MainInner(string[] args)
         {
             try

Original file line number	Diff line number	Diff line change
`@@ -215,9 +215,23 @@ private static Parser BuildCommandLine()`
`215`	`215`	`}`
`216`	`216`	`}`
`217`	`217`	`}, (MiddlewareOrder)(-3000)) // MiddlewareOrderInternal.ExceptionHandler so [parse] directive is accurate.`
	`218`	`+ .UseExceptionHandler((ex, context) => PrintException(ex, context))`
`218`	`219`	`.Build();`
`219`	`220`	`}`
`220`	`221`
	`222`	`+ private static void PrintException(Exception ex, InvocationContext context)`
	`223`	`+ {`
	`224`	`+ try`
	`225`	`+ {`
	`226`	`+ Console.Error.WriteLine("Unhandled exception: {0}", ex);`
	`227`	`+ }`
	`228`	`+ catch (Exception ex2)`
	`229`	`+ {`
	`230`	`+ Console.Error.WriteLine("Unhandled exception: {0}", ex.Message);`
	`231`	`+ Console.Error.WriteLine("Unhandled exception while trying to print string version of the above exception: {0}", ex2);`
	`232`	`+ }`
	`233`	`+ }`
	`234`	`+`
`221`	`235`	`private static int MainInner(string[] args)`
`222`	`236`	`{`
`223`	`237`	`try`