accounts/abi/bind: allow client to specify sender address for call (#3782)

accounts/abi/bind/base.go

@@ -36,6 +36,7 @@ type SignerFn func(types.Signer, common.Address, *types.Transaction) (*types.Tra
 // CallOpts is the collection of options to fine tune a contract call request.
 type CallOpts struct {
 	Pending bool           // Whether to operate on the pending state or the last known one
+	From    common.Address // Optional the sender address, otherwise the first account is used
 
 	Context context.Context // Network context to support cancellation and timeouts (nil = no timeout)
 }
@@ -108,7 +109,7 @@ func (c *BoundContract) Call(opts *CallOpts, result interface{}, method string,
 		return err
 	}
 	var (
-		msg    = ethereum.CallMsg{To: &c.address, Data: input}
+		msg    = ethereum.CallMsg{From: opts.From, To: &c.address, Data: input}
 		ctx    = ensureContext(opts.Context)
 		code   []byte
 		output []byte

accounts/abi/bind/bind_test.go

@@ -408,6 +408,45 @@ var bindTests = []struct {
 			}
 		`,
 	},
+	// Test that constant functions can be called from an (optional) specified address
+	{
+		`CallFrom`,
+		`
+			contract CallFrom {
+				function callFrom() constant returns(address) {
+					return msg.sender;
+				}
+			}
+		`, `6060604052346000575b6086806100176000396000f300606060405263ffffffff60e060020a60003504166349f8e98281146022575b6000565b34600057602c6055565b6040805173ffffffffffffffffffffffffffffffffffffffff9092168252519081900360200190f35b335b905600a165627a7a72305820aef6b7685c0fa24ba6027e4870404a57df701473fe4107741805c19f5138417c0029`,
+		`[{"constant":true,"inputs":[],"name":"callFrom","outputs":[{"name":"","type":"address"}],"payable":false,"type":"function"}]`,
+		`
+			// Generate a new random account and a funded simulator
+			key, _ := crypto.GenerateKey()
+			auth := bind.NewKeyedTransactor(key)
+			sim := backends.NewSimulatedBackend(core.GenesisAccount{Address: auth.From, Balance: big.NewInt(10000000000)})
+
+			// Deploy a sender tester contract and execute a structured call on it
+			_, _, callfrom, err := DeployCallFrom(auth, sim)
+			if err != nil {
+				t.Fatalf("Failed to deploy sender contract: %v", err)
+			}
+			sim.Commit()
+
+			if res, err := callfrom.CallFrom(nil); err != nil {
+				t.Errorf("Failed to call constant function: %v", err)
+			} else if res != (common.Address{}) {
+				t.Errorf("Invalid address returned, want: %x, got: %x", (common.Address{}), res)
+			}
+
+			for _, addr := range []common.Address{common.Address{}, common.Address{1}, common.Address{2}} {
+				if res, err := callfrom.CallFrom(&bind.CallOpts{From: addr}); err != nil {
+					t.Fatalf("Failed to call constant function: %v", err)
+				} else if res != addr {
+					t.Fatalf("Invalid address returned, want: %x, got: %x", addr, res)
+				}
+			}
+		`,
+	},
 }
 
 // Tests that packages generated by the binder can be successfully compiled and