From 6e876761607fa0c0e87d6da293d7a0121613b4ae Mon Sep 17 00:00:00 2001
From: Mackenzie Clark <mackenzie.a.z.c@gmail.com>
Date: Thu, 14 Feb 2019 18:40:52 -0800
Subject: [PATCH] Impl error for link error (#182)

---
 lib/runtime-core/src/error.rs | 25 +++++++++++++++++++++++++
 1 file changed, 25 insertions(+)

diff --git a/lib/runtime-core/src/error.rs b/lib/runtime-core/src/error.rs
index 734e11cff..9e1eba8fe 100644
--- a/lib/runtime-core/src/error.rs
+++ b/lib/runtime-core/src/error.rs
@@ -76,6 +76,31 @@ impl PartialEq for LinkError {
     }
 }
 
+impl std::fmt::Display for LinkError {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        match self {
+            LinkError::ImportNotFound {namespace, name} => write!(f, "Import not found, namespace: {}, name: {}", namespace, name),
+            LinkError::IncorrectGlobalDescriptor {namespace, name,expected,found} => {
+                write!(f, "Incorrect global descriptor, namespace: {}, name: {}, expected global descriptor: {:?}, found global descriptor: {:?}", namespace, name, expected, found)
+            },
+            LinkError::IncorrectImportSignature{namespace, name,expected,found} => {
+                write!(f, "Incorrect import signature, namespace: {}, name: {}, expected signature: {}, found signature: {}", namespace, name, expected, found)
+            }
+            LinkError::IncorrectImportType{namespace, name,expected,found} => {
+                write!(f, "Incorrect import type, namespace: {}, name: {}, expected type: {}, found type: {}", namespace, name, expected, found)
+            }
+            LinkError::IncorrectMemoryDescriptor{namespace, name,expected,found} => {
+                write!(f, "Incorrect memory descriptor, namespace: {}, name: {}, expected memory descriptor: {:?}, found memory descriptor: {:?}", namespace, name, expected, found)
+            },
+            LinkError::IncorrectTableDescriptor{namespace, name,expected,found} => {
+                write!(f, "Incorrect table descriptor, namespace: {}, name: {}, expected table descriptor: {:?}, found table descriptor: {:?}", namespace, name, expected, found)
+            },
+        }
+    }
+}
+
+impl std::error::Error for LinkError {}
+
 /// This is the error type returned when calling
 /// a webassembly function.
 ///