accounts/abi/bind, eth: add contract non-existent error

accounts/abi/bind/bind_test.go

@@ -303,6 +303,34 @@ var bindTests = []struct {
 			}
 		`,
 	},
+	// Tests that non-existent contracts are reported as such (though only simulator test)
+	{
+		`NonExistent`,
+		`
+		contract NonExistent {
+			function String() constant returns(string) {
+				return "I don't exist";
+			}
+		}
+		`,
+		`6060604052609f8060106000396000f3606060405260e060020a6000350463f97a60058114601a575b005b600060605260c0604052600d60809081527f4920646f6e27742065786973740000000000000000000000000000000000000060a052602060c0908152600d60e081905281906101009060a09080838184600060046012f15050815172ffffffffffffffffffffffffffffffffffffff1916909152505060405161012081900392509050f3`,
+		`[{"constant":true,"inputs":[],"name":"String","outputs":[{"name":"","type":"string"}],"type":"function"}]`,
+		`
+			// Create a simulator and wrap a non-deployed contract
+			sim := backends.NewSimulatedBackend()
+
+			nonexistent, err := NewNonExistent(common.Address{}, sim)
+			if err != nil {
+				t.Fatalf("Failed to access non-existent contract: %v", err)
+			}
+			// Ensure that contract calls fail with the appropriate error
+			if res, err := nonexistent.String(nil); err == nil {
+				t.Fatalf("Call succeeded on non-existent contract: %v", res)
+			} else if (err != bind.ErrNoCode) {
+				t.Fatalf("Error mismatch: have %v, want %v", err, bind.ErrNoCode)
+			}
+		`,
+	},
 }
 
 // Tests that packages generated by the binder can be successfully compiled and