ImportHook preserves the original exception message when an import fails

tminka · tminka · commit 31236b5140f8 · 2021-01-04T00:49:06.000Z
diff --git a/src/runtime/importhook.cs b/src/runtime/importhook.cs
@@ -291,6 +291,9 @@ public static IntPtr __import__(IntPtr self, IntPtr args, IntPtr kw)
                 // We don't support them anyway
                 return IntPtr.Zero;
             }
+            // Save the exception
+            var originalException = new PythonException();
+            var originalExceptionMessage = originalException.ToString();
             // Otherwise,  just clear the it.
             Exceptions.Clear();
 
@@ -342,7 +345,7 @@ public static IntPtr __import__(IntPtr self, IntPtr args, IntPtr kw)
                 ManagedType mt = tail.GetAttribute(name, true);
                 if (!(mt is ModuleObject))
                 {
-                    Exceptions.SetError(Exceptions.ImportError, $"No module named {name}");
+                    Exceptions.SetError(Exceptions.ImportError, originalExceptionMessage);
                     return IntPtr.Zero;
                 }
                 if (head == null)

Original file line number	Diff line number	Diff line change
`@@ -291,6 +291,9 @@ public static IntPtr __import__(IntPtr self, IntPtr args, IntPtr kw)`
`291`	`291`	`// We don't support them anyway`
`292`	`292`	`return IntPtr.Zero;`
`293`	`293`	`}`
	`294`	`+ // Save the exception`
	`295`	`+ var originalException = new PythonException();`
	`296`	`+ var originalExceptionMessage = originalException.ToString();`
`294`	`297`	`// Otherwise, just clear the it.`
`295`	`298`	`Exceptions.Clear();`
`296`	`299`
`@@ -342,7 +345,7 @@ public static IntPtr __import__(IntPtr self, IntPtr args, IntPtr kw)`
`342`	`345`	`ManagedType mt = tail.GetAttribute(name, true);`
`343`	`346`	`if (!(mt is ModuleObject))`
`344`	`347`	`{`
`345`		`- Exceptions.SetError(Exceptions.ImportError, $"No module named {name}");`
	`348`	`+ Exceptions.SetError(Exceptions.ImportError, originalExceptionMessage);`
`346`	`349`	`return IntPtr.Zero;`
`347`	`350`	`}`
`348`	`351`	`if (head == null)`