accounts/abi: generate TryPack* methods for abigen v2 bindings

accounts/abi/abigen/bindv2_test.go

@@ -281,7 +281,7 @@ func TestBindingV2ConvertedV1Tests(t *testing.T) {
 			}
 			// Set this environment variable to regenerate the test outputs.
 			if os.Getenv("WRITE_TEST_FILES") != "" {
-				if err := os.WriteFile((fname), []byte(have), 0666); err != nil {
+				if err := os.WriteFile(fname, []byte(have), 0666); err != nil {
 					t.Fatalf("err writing expected output to file: %v\n", err)
 				}
 			}

accounts/abi/abigen/source2.go.tpl

@@ -89,7 +89,7 @@ var (
 	{{ end }}
 
 	{{range .Calls}}
-		// Pack{{.Normalized.Name}} is the Go binding used to pack the parameters required for calling
+		// Pack{{.Normalized.Name}} is the Go binding used to pack the parameters required for calling, will panic for any error.
 		// the contract method with ID 0x{{printf "%x" .Original.ID}}.
 		//
 		// Solidity: {{.Original.String}}
@@ -101,6 +101,14 @@ var (
 			return enc
 		}
 
+		// Pack{{.Normalized.Name}} is the Go binding used to pack the parameters required for calling, return error if it failed to pack.
+		// the contract method with ID 0x{{printf "%x" .Original.ID}}.
+		//
+		// Solidity: {{.Original.String}}
+		func ({{ decapitalise $contract.Type}} *{{$contract.Type}}) TryPack{{.Normalized.Name}}({{range .Normalized.Inputs}} {{.Name}} {{bindtype .Type $structs}}, {{end}}) ([]byte, error) {
+			return {{ decapitalise $contract.Type}}.abi.Pack("{{.Original.Name}}" {{range .Normalized.Inputs}}, {{.Name}}{{end}})
+		}
+
 		{{/* Unpack method is needed only when there are return args */}}
 		{{if .Normalized.Outputs }}
 			{{ if .Structured }}
@@ -117,24 +125,23 @@ var (
 			//
 			// Solidity: {{.Original.String}}
 			func ({{ decapitalise $contract.Type}} *{{$contract.Type}}) Unpack{{.Normalized.Name}}(data []byte) (
-				{{- if .Structured}} {{.Normalized.Name}}Output,{{else}}
+				{{- if .Structured}} *{{.Normalized.Name}}Output,{{else}}
 				{{- range .Normalized.Outputs}} {{bindtype .Type $structs}},{{- end }}
 				{{- end }} error) {
 				out, err := {{ decapitalise $contract.Type}}.abi.Unpack("{{.Original.Name}}", data)
 				{{- if .Structured}}
-				outstruct := new({{.Normalized.Name}}Output)
 				if err != nil {
-					return *outstruct, err
+					return nil, err
 				}
+				outstruct := new({{.Normalized.Name}}Output)
 				{{- range $i, $t := .Normalized.Outputs}}
 				{{- if ispointertype .Type}}
 					outstruct.{{capitalise .Name}} = abi.ConvertType(out[{{$i}}], new({{underlyingbindtype .Type }})).({{bindtype .Type $structs}})
 				{{- else }}
 					outstruct.{{capitalise .Name}} = *abi.ConvertType(out[{{$i}}], new({{bindtype .Type $structs}})).(*{{bindtype .Type $structs}})
 				{{- end }}
 				{{- end }}
-				return *outstruct, err
-				{{else}}
+				return outstruct, nil{{else}}
 				if err != nil {
 					return {{range $i, $_ := .Normalized.Outputs}}{{if ispointertype .Type}}new({{underlyingbindtype .Type }}), {{else}}*new({{bindtype .Type $structs}}), {{end}}{{end}} err
 				}
@@ -145,8 +152,7 @@ var (
 				out{{$i}} := *abi.ConvertType(out[{{$i}}], new({{bindtype .Type $structs}})).(*{{bindtype .Type $structs}})
 				{{- end }}
 				{{- end}}
-				return {{range $i, $t := .Normalized.Outputs}}out{{$i}}, {{end}} err
-                {{- end}}
+				return {{range $i, $t := .Normalized.Outputs}}out{{$i}}, {{end}} nil{{- end}}
 			}
 		{{end}}
 	{{end}}

accounts/abi/abigen/testdata/v2/callbackparam.go.txt

@@ -51,7 +51,7 @@ func (c *CallbackParam) Instance(backend bind.ContractBackend, addr common.Addre
 	return bind.NewBoundContract(addr, c.abi, backend, backend, backend)
 }
 
-// PackTest is the Go binding used to pack the parameters required for calling
+// PackTest is the Go binding used to pack the parameters required for calling, will panic for any error.
 // the contract method with ID 0xd7a5aba2.
 //
 // Solidity: function test(function callback) returns()
@@ -62,3 +62,11 @@ func (callbackParam *CallbackParam) PackTest(callback [24]byte) []byte {
 	}
 	return enc
 }
+
+// PackTest is the Go binding used to pack the parameters required for calling, return error if it failed to pack.
+// the contract method with ID 0xd7a5aba2.
+//
+// Solidity: function test(function callback) returns()
+func (callbackParam *CallbackParam) TryPackTest(callback [24]byte) ([]byte, error) {
+	return callbackParam.abi.Pack("test", callback)
+}

accounts/abi/abigen/testdata/v2/crowdsale.go.txt

@@ -63,7 +63,7 @@ func (crowdsale *Crowdsale) PackConstructor(ifSuccessfulSendTo common.Address, f
 	return enc
 }
 
-// PackAmountRaised is the Go binding used to pack the parameters required for calling
+// PackAmountRaised is the Go binding used to pack the parameters required for calling, will panic for any error.
 // the contract method with ID 0x7b3e5e7b.
 //
 // Solidity: function amountRaised() returns(uint256)
@@ -75,6 +75,14 @@ func (crowdsale *Crowdsale) PackAmountRaised() []byte {
 	return enc
 }
 
+// PackAmountRaised is the Go binding used to pack the parameters required for calling, return error if it failed to pack.
+// the contract method with ID 0x7b3e5e7b.
+//
+// Solidity: function amountRaised() returns(uint256)
+func (crowdsale *Crowdsale) TryPackAmountRaised() ([]byte, error) {
+	return crowdsale.abi.Pack("amountRaised")
+}
+
 // UnpackAmountRaised is the Go binding that unpacks the parameters returned
 // from invoking the contract method with ID 0x7b3e5e7b.
 //
@@ -85,10 +93,10 @@ func (crowdsale *Crowdsale) UnpackAmountRaised(data []byte) (*big.Int, error) {
 		return new(big.Int), err
 	}
 	out0 := abi.ConvertType(out[0], new(big.Int)).(*big.Int)
-	return out0, err
+	return out0, nil
 }
 
-// PackBeneficiary is the Go binding used to pack the parameters required for calling
+// PackBeneficiary is the Go binding used to pack the parameters required for calling, will panic for any error.
 // the contract method with ID 0x38af3eed.
 //
 // Solidity: function beneficiary() returns(address)
@@ -100,6 +108,14 @@ func (crowdsale *Crowdsale) PackBeneficiary() []byte {
 	return enc
 }
 
+// PackBeneficiary is the Go binding used to pack the parameters required for calling, return error if it failed to pack.
+// the contract method with ID 0x38af3eed.
+//
+// Solidity: function beneficiary() returns(address)
+func (crowdsale *Crowdsale) TryPackBeneficiary() ([]byte, error) {
+	return crowdsale.abi.Pack("beneficiary")
+}
+
 // UnpackBeneficiary is the Go binding that unpacks the parameters returned
 // from invoking the contract method with ID 0x38af3eed.
 //
@@ -110,10 +126,10 @@ func (crowdsale *Crowdsale) UnpackBeneficiary(data []byte) (common.Address, erro
 		return *new(common.Address), err
 	}
 	out0 := *abi.ConvertType(out[0], new(common.Address)).(*common.Address)
-	return out0, err
+	return out0, nil
 }
 
-// PackCheckGoalReached is the Go binding used to pack the parameters required for calling
+// PackCheckGoalReached is the Go binding used to pack the parameters required for calling, will panic for any error.
 // the contract method with ID 0x01cb3b20.
 //
 // Solidity: function checkGoalReached() returns()
@@ -125,7 +141,15 @@ func (crowdsale *Crowdsale) PackCheckGoalReached() []byte {
 	return enc
 }
 
-// PackDeadline is the Go binding used to pack the parameters required for calling
+// PackCheckGoalReached is the Go binding used to pack the parameters required for calling, return error if it failed to pack.
+// the contract method with ID 0x01cb3b20.
+//
+// Solidity: function checkGoalReached() returns()
+func (crowdsale *Crowdsale) TryPackCheckGoalReached() ([]byte, error) {
+	return crowdsale.abi.Pack("checkGoalReached")
+}
+
+// PackDeadline is the Go binding used to pack the parameters required for calling, will panic for any error.
 // the contract method with ID 0x29dcb0cf.
 //
 // Solidity: function deadline() returns(uint256)
@@ -137,6 +161,14 @@ func (crowdsale *Crowdsale) PackDeadline() []byte {
 	return enc
 }
 
+// PackDeadline is the Go binding used to pack the parameters required for calling, return error if it failed to pack.
+// the contract method with ID 0x29dcb0cf.
+//
+// Solidity: function deadline() returns(uint256)
+func (crowdsale *Crowdsale) TryPackDeadline() ([]byte, error) {
+	return crowdsale.abi.Pack("deadline")
+}
+
 // UnpackDeadline is the Go binding that unpacks the parameters returned
 // from invoking the contract method with ID 0x29dcb0cf.
 //
@@ -147,10 +179,10 @@ func (crowdsale *Crowdsale) UnpackDeadline(data []byte) (*big.Int, error) {
 		return new(big.Int), err
 	}
 	out0 := abi.ConvertType(out[0], new(big.Int)).(*big.Int)
-	return out0, err
+	return out0, nil
 }
 
-// PackFunders is the Go binding used to pack the parameters required for calling
+// PackFunders is the Go binding used to pack the parameters required for calling, will panic for any error.
 // the contract method with ID 0xdc0d3dff.
 //
 // Solidity: function funders(uint256 ) returns(address addr, uint256 amount)
@@ -162,6 +194,14 @@ func (crowdsale *Crowdsale) PackFunders(arg0 *big.Int) []byte {
 	return enc
 }
 
+// PackFunders is the Go binding used to pack the parameters required for calling, return error if it failed to pack.
+// the contract method with ID 0xdc0d3dff.
+//
+// Solidity: function funders(uint256 ) returns(address addr, uint256 amount)
+func (crowdsale *Crowdsale) TryPackFunders(arg0 *big.Int) ([]byte, error) {
+	return crowdsale.abi.Pack("funders", arg0)
+}
+
 // FundersOutput serves as a container for the return parameters of contract
 // method Funders.
 type FundersOutput struct {
@@ -173,19 +213,18 @@ type FundersOutput struct {
 // from invoking the contract method with ID 0xdc0d3dff.
 //
 // Solidity: function funders(uint256 ) returns(address addr, uint256 amount)
-func (crowdsale *Crowdsale) UnpackFunders(data []byte) (FundersOutput, error) {
+func (crowdsale *Crowdsale) UnpackFunders(data []byte) (*FundersOutput, error) {
 	out, err := crowdsale.abi.Unpack("funders", data)
-	outstruct := new(FundersOutput)
 	if err != nil {
-		return *outstruct, err
+		return nil, err
 	}
+	outstruct := new(FundersOutput)
 	outstruct.Addr = *abi.ConvertType(out[0], new(common.Address)).(*common.Address)
 	outstruct.Amount = abi.ConvertType(out[1], new(big.Int)).(*big.Int)
-	return *outstruct, err
-
+	return outstruct, nil
 }
 
-// PackFundingGoal is the Go binding used to pack the parameters required for calling
+// PackFundingGoal is the Go binding used to pack the parameters required for calling, will panic for any error.
 // the contract method with ID 0x7a3a0e84.
 //
 // Solidity: function fundingGoal() returns(uint256)
@@ -197,6 +236,14 @@ func (crowdsale *Crowdsale) PackFundingGoal() []byte {
 	return enc
 }
 
+// PackFundingGoal is the Go binding used to pack the parameters required for calling, return error if it failed to pack.
+// the contract method with ID 0x7a3a0e84.
+//
+// Solidity: function fundingGoal() returns(uint256)
+func (crowdsale *Crowdsale) TryPackFundingGoal() ([]byte, error) {
+	return crowdsale.abi.Pack("fundingGoal")
+}
+
 // UnpackFundingGoal is the Go binding that unpacks the parameters returned
 // from invoking the contract method with ID 0x7a3a0e84.
 //
@@ -207,10 +254,10 @@ func (crowdsale *Crowdsale) UnpackFundingGoal(data []byte) (*big.Int, error) {
 		return new(big.Int), err
 	}
 	out0 := abi.ConvertType(out[0], new(big.Int)).(*big.Int)
-	return out0, err
+	return out0, nil
 }
 
-// PackPrice is the Go binding used to pack the parameters required for calling
+// PackPrice is the Go binding used to pack the parameters required for calling, will panic for any error.
 // the contract method with ID 0xa035b1fe.
 //
 // Solidity: function price() returns(uint256)
@@ -222,6 +269,14 @@ func (crowdsale *Crowdsale) PackPrice() []byte {
 	return enc
 }
 
+// PackPrice is the Go binding used to pack the parameters required for calling, return error if it failed to pack.
+// the contract method with ID 0xa035b1fe.
+//
+// Solidity: function price() returns(uint256)
+func (crowdsale *Crowdsale) TryPackPrice() ([]byte, error) {
+	return crowdsale.abi.Pack("price")
+}
+
 // UnpackPrice is the Go binding that unpacks the parameters returned
 // from invoking the contract method with ID 0xa035b1fe.
 //
@@ -232,10 +287,10 @@ func (crowdsale *Crowdsale) UnpackPrice(data []byte) (*big.Int, error) {
 		return new(big.Int), err
 	}
 	out0 := abi.ConvertType(out[0], new(big.Int)).(*big.Int)
-	return out0, err
+	return out0, nil
 }
 
-// PackTokenReward is the Go binding used to pack the parameters required for calling
+// PackTokenReward is the Go binding used to pack the parameters required for calling, will panic for any error.
 // the contract method with ID 0x6e66f6e9.
 //
 // Solidity: function tokenReward() returns(address)
@@ -247,6 +302,14 @@ func (crowdsale *Crowdsale) PackTokenReward() []byte {
 	return enc
 }
 
+// PackTokenReward is the Go binding used to pack the parameters required for calling, return error if it failed to pack.
+// the contract method with ID 0x6e66f6e9.
+//
+// Solidity: function tokenReward() returns(address)
+func (crowdsale *Crowdsale) TryPackTokenReward() ([]byte, error) {
+	return crowdsale.abi.Pack("tokenReward")
+}
+
 // UnpackTokenReward is the Go binding that unpacks the parameters returned
 // from invoking the contract method with ID 0x6e66f6e9.
 //
@@ -257,7 +320,7 @@ func (crowdsale *Crowdsale) UnpackTokenReward(data []byte) (common.Address, erro
 		return *new(common.Address), err
 	}
 	out0 := *abi.ConvertType(out[0], new(common.Address)).(*common.Address)
-	return out0, err
+	return out0, nil
 }
 
 // CrowdsaleFundTransfer represents a FundTransfer event raised by the Crowdsale contract.