[#2] Fix test

Use `require` to check for errors and instead of just printing result to Stdout,
t.Log to print errors.
Added functions to calculate start offset, check if contract
method has result and to get random int to put.

Signed-off-by: Ekaterina Lebedeva <ekaterina.lebedeva@yadro.com>

tests/contract_test.go

@@ -1,11 +1,14 @@
 package contract
 
 import (
+	"errors"
+	"math/rand"
 	"path"
 	"testing"
 
 	"git.frostfs.info/TrueCloudLab/contract-coverage-primer/covertest"
 	"github.com/davecgh/go-spew/spew"
+	"github.com/nspcc-dev/neo-go/pkg/compiler"
 	"github.com/nspcc-dev/neo-go/pkg/neotest"
 	"github.com/nspcc-dev/neo-go/pkg/neotest/chain"
 	"github.com/nspcc-dev/neo-go/pkg/smartcontract/callflag"
@@ -52,23 +55,31 @@ func TestRun(t *testing.T) {
 	ctrDI := covertest.CompileFile(t, e.CommitteeHash, ctrPath, path.Join(ctrPath, "config.yml"))
 	e.DeployContract(t, ctrDI.Contract, nil)
 
+	startOffsetPutNumber, err := getStartOffset(ctrDI.DebugInfo, "PutNumber")
+	require.NoError(t, err)
+
+	hasResult, err := hasResult(ctrDI.DebugInfo, "PutNumber")
+	require.NoError(t, err)
+
+	someNum := getNumToPut()
+
 	// setting up a VM for covertest.Run()
-	covertestRunVM := setUpVMForPut(t, e, ctrDI.Contract, false, 101, 2, invalidKey)
-	res, err := covertest.Run(covertestRunVM)
-	spew.Println("Printing collected instructions:")
+	covertestRunVM := setUpVMForPut(t, e, ctrDI.Contract, hasResult, startOffsetPutNumber, someNum, invalidKey)
+	res, covErr := covertest.Run(covertestRunVM)
+	t.Log("Printing collected instructions:")
 	spew.Dump(res)
-	spew.Println("covertest.Run() returned an error: ", err)
+	t.Log("covertest.Run() returned an error: ", covErr)
 
 	// setting up a VM for vm.Run()
-	origRunVM := setUpVMForPut(t, e, ctrDI.Contract, false, 101, 2, invalidKey)
+	origRunVM := setUpVMForPut(t, e, ctrDI.Contract, hasResult, startOffsetPutNumber, someNum, invalidKey)
 	runerr := origRunVM.Run()
-	spew.Println("vm.Run() returned an error: ", err)
+	t.Log("vm.Run() returned an error: ", covErr)
 
 	//check if errors are the same
-	spew.Println("Are errors the same? ", runerr.Error() == runerr.Error())
+	require.Equal(t, runerr.Error(), covErr.Error())
 
 	//check if the number of elements on the stack is the same
-	spew.Println("Is the number of elements on the stack the same? ", origRunVM.Estack().Len() == covertestRunVM.Estack().Len())
+	require.Equal(t, origRunVM.Estack().Len(), covertestRunVM.Estack().Len())
 }
 
 func setUpVMForPut(t *testing.T, e *neotest.Executor, contract *neotest.Contract, hasResult bool, methodOff int, num int, key []byte) (v *vm.VM) {
@@ -79,3 +90,28 @@ func setUpVMForPut(t *testing.T, e *neotest.Executor, contract *neotest.Contract
 	ic.VM.Context().Estack().PushVal(key)
 	return ic.VM
 }
+
+func getStartOffset(di *compiler.DebugInfo, methodID string) (int, error) {
+	for _, method := range di.Methods {
+		if method.ID == methodID {
+			return int(method.Range.Start), nil
+		}
+	}
+	return 0, errors.New("Method not found")
+}
+
+func hasResult(di *compiler.DebugInfo, methodID string) (bool, error) {
+	for _, method := range di.Methods {
+		if method.ID == methodID {
+			if method.ReturnType == "Void" {
+				return false, nil
+			}
+			return true, nil
+		}
+	}
+	return false, errors.New("Method not found")
+}
+
+func getNumToPut() int {
+	return rand.Intn(100)
+}