Improve error message

codecov.yml

@@ -2,8 +2,8 @@ coverage:
   status:
     project:
       default:
-        target: 80%
-        threshold: 4%
+        target: 85%
+        threshold: 3%
     patch:
       default:
         target: 75%

internal/mongo/errors.go

@@ -1,20 +1,31 @@
 package mongo
 
-// GenerationError is an error from generating MongoDB repository
-type GenerationError string
-
-func (err GenerationError) Error() string {
-	switch err {
-	case OperationNotSupportedError:
-		return "operation not supported"
-	case BsonTagNotFoundError:
-		return "bson tag not found"
-	}
-	return string(err)
-}
-
-// generation error constants
-const (
-	OperationNotSupportedError GenerationError = "ERROR_OPERATION_NOT_SUPPORTED"
-	BsonTagNotFoundError       GenerationError = "ERROR_BSON_TAG_NOT_FOUND"
+import (
+	"fmt"
 )
+
+// NewOperationNotSupportedError creates operationNotSupportedError
+func NewOperationNotSupportedError(operationName string) error {
+	return operationNotSupportedError{OperationName: operationName}
+}
+
+type operationNotSupportedError struct {
+	OperationName string
+}
+
+func (err operationNotSupportedError) Error() string {
+	return fmt.Sprintf("operation '%s' not supported", err.OperationName)
+}
+
+// NewBsonTagNotFoundError creates bsonTagNotFoundError
+func NewBsonTagNotFoundError(fieldName string) error {
+	return bsonTagNotFoundError{FieldName: fieldName}
+}
+
+type bsonTagNotFoundError struct {
+	FieldName string
+}
+
+func (err bsonTagNotFoundError) Error() string {
+	return fmt.Sprintf("bson tag of field '%s' not found", err.FieldName)
+}

internal/mongo/errors_test.go

@@ -0,0 +1,36 @@
+package mongo_test
+
+import (
+	"testing"
+
+	"github.com/sunboyy/repogen/internal/mongo"
+)
+
+type ErrorTestCase struct {
+	Name           string
+	Error          error
+	ExpectedString string
+}
+
+func TestError(t *testing.T) {
+	testTable := []ErrorTestCase{
+		{
+			Name:           "OperationNotSupportedError",
+			Error:          mongo.NewOperationNotSupportedError("Stub"),
+			ExpectedString: "operation 'Stub' not supported",
+		},
+		{
+			Name:           "BsonTagNotFoundError",
+			Error:          mongo.NewBsonTagNotFoundError("AccessToken"),
+			ExpectedString: "bson tag of field 'AccessToken' not found",
+		},
+	}
+
+	for _, testCase := range testTable {
+		t.Run(testCase.Name, func(t *testing.T) {
+			if testCase.Error.Error() != testCase.ExpectedString {
+				t.Errorf("Expected = %v\nReceived = %v", testCase.ExpectedString, testCase.Error.Error())
+			}
+		})
+	}
+}

internal/mongo/generator.go

@@ -87,9 +87,9 @@ func (g RepositoryGenerator) generateMethodImplementation(methodSpec spec.Method
 		return g.generateDeleteImplementation(operation)
 	case spec.CountOperation:
 		return g.generateCountImplementation(operation)
+	default:
+		return "", NewOperationNotSupportedError(operation.Name())
 	}
-
-	return "", OperationNotSupportedError
 }
 
 func (g RepositoryGenerator) generateInsertImplementation(operation spec.InsertOperation) (string, error) {
@@ -201,7 +201,7 @@ func (g RepositoryGenerator) bsonTagFromFieldName(fieldName string) (string, err
 
 	bsonTag, ok := structField.Tags["bson"]
 	if !ok {
-		return "", BsonTagNotFoundError
+		return "", NewBsonTagNotFoundError(fieldName)
 	}
 
 	return bsonTag[0], nil

internal/mongo/generator_test.go

@@ -1453,6 +1453,13 @@ type GenerateMethodInvalidTestCase struct {
 	ExpectedError error
 }
 
+type StubOperation struct {
+}
+
+func (o StubOperation) Name() string {
+	return "Stub"
+}
+
 func TestGenerateMethod_Invalid(t *testing.T) {
 	testTable := []GenerateMethodInvalidTestCase{
 		{
@@ -1467,9 +1474,9 @@ func TestGenerateMethod_Invalid(t *testing.T) {
 					code.ArrayType{ContainedType: code.PointerType{ContainedType: code.SimpleType("UserModel")}},
 					code.SimpleType("error"),
 				},
-				Operation: "search",
+				Operation: StubOperation{},
 			},
-			ExpectedError: mongo.OperationNotSupportedError,
+			ExpectedError: mongo.NewOperationNotSupportedError("Stub"),
 		},
 		{
 			Name: "bson tag not found in query",
@@ -1492,7 +1499,7 @@ func TestGenerateMethod_Invalid(t *testing.T) {
 					},
 				},
 			},
-			ExpectedError: mongo.BsonTagNotFoundError,
+			ExpectedError: mongo.NewBsonTagNotFoundError("AccessToken"),
 		},
 		{
 			Name: "bson tag not found in update field",
@@ -1519,7 +1526,7 @@ func TestGenerateMethod_Invalid(t *testing.T) {
 					},
 				},
 			},
-			ExpectedError: mongo.BsonTagNotFoundError,
+			ExpectedError: mongo.NewBsonTagNotFoundError("AccessToken"),
 		},
 	}
 

internal/spec/errors.go

@@ -1,38 +1,73 @@
 package spec
 
+import (
+	"fmt"
+	"strings"
+)
+
 // ParsingError is an error from parsing interface methods
 type ParsingError string
 
 func (err ParsingError) Error() string {
 	switch err {
-	case UnknownOperationError:
-		return "unknown operation"
-	case UnsupportedNameError:
-		return "method name is not supported"
 	case UnsupportedReturnError:
 		return "this type of return is not supported"
-	case InvalidQueryError:
-		return "invalid query"
+	case QueryRequiredError:
+		return "query is required"
 	case InvalidParamError:
 		return "parameters do not match the query"
 	case InvalidUpdateFieldsError:
 		return "update fields is invalid"
 	case ContextParamRequiredError:
 		return "context parameter is required"
-	case StructFieldNotFoundError:
-		return "struct field not found"
 	}
 	return string(err)
 }
 
 // parsing error constants
 const (
-	UnknownOperationError     ParsingError = "ERROR_UNKNOWN_OPERATION"
-	UnsupportedNameError      ParsingError = "ERROR_UNSUPPORTED"
 	UnsupportedReturnError    ParsingError = "ERROR_UNSUPPORTED_RETURN"
-	InvalidQueryError         ParsingError = "ERROR_INVALID_QUERY"
+	QueryRequiredError        ParsingError = "ERROR_QUERY_REQUIRED"
 	InvalidParamError         ParsingError = "ERROR_INVALID_PARAM"
 	InvalidUpdateFieldsError  ParsingError = "ERROR_INVALID_UPDATE_FIELDS"
 	ContextParamRequiredError ParsingError = "ERROR_CONTEXT_PARAM_REQUIRED"
-	StructFieldNotFoundError  ParsingError = "ERROR_STRUCT_FIELD_NOT_FOUND"
 )
+
+// NewInvalidQueryError creates invalidQueryError
+func NewInvalidQueryError(queryTokens []string) error {
+	return invalidQueryError{QueryString: strings.Join(queryTokens, "")}
+}
+
+type invalidQueryError struct {
+	QueryString string
+}
+
+func (err invalidQueryError) Error() string {
+	return fmt.Sprintf("invalid query '%s'", err.QueryString)
+}
+
+// NewUnknownOperationError creates unknownOperationError
+func NewUnknownOperationError(operationName string) error {
+	return unknownOperationError{OperationName: operationName}
+}
+
+type unknownOperationError struct {
+	OperationName string
+}
+
+func (err unknownOperationError) Error() string {
+	return fmt.Sprintf("unknown operation '%s'", err.OperationName)
+}
+
+// NewStructFieldNotFoundError creates structFieldNotFoundError
+func NewStructFieldNotFoundError(fieldName string) error {
+	return structFieldNotFoundError{FieldName: fieldName}
+}
+
+type structFieldNotFoundError struct {
+	FieldName string
+}
+
+func (err structFieldNotFoundError) Error() string {
+	return fmt.Sprintf("struct field '%s' not found", err.FieldName)
+}

internal/spec/errors_test.go

@@ -0,0 +1,41 @@
+package spec_test
+
+import (
+	"testing"
+
+	"github.com/sunboyy/repogen/internal/spec"
+)
+
+type ErrorTestCase struct {
+	Name           string
+	Error          error
+	ExpectedString string
+}
+
+func TestError(t *testing.T) {
+	testTable := []ErrorTestCase{
+		{
+			Name:           "UnknownOperationError",
+			Error:          spec.NewUnknownOperationError("Search"),
+			ExpectedString: "unknown operation 'Search'",
+		},
+		{
+			Name:           "StructFieldNotFoundError",
+			Error:          spec.NewStructFieldNotFoundError("Country"),
+			ExpectedString: "struct field 'Country' not found",
+		},
+		{
+			Name:           "InvalidQueryError",
+			Error:          spec.NewInvalidQueryError([]string{"By", "And"}),
+			ExpectedString: "invalid query 'ByAnd'",
+		},
+	}
+
+	for _, testCase := range testTable {
+		t.Run(testCase.Name, func(t *testing.T) {
+			if testCase.Error.Error() != testCase.ExpectedString {
+				t.Errorf("Expected = %v\nReceived = %v", testCase.ExpectedString, testCase.Error.Error())
+			}
+		})
+	}
+}

internal/spec/models.go

@@ -23,6 +23,7 @@ type MethodSpec struct {
 
 // Operation is an interface for any kind of operation
 type Operation interface {
+	Name() string
 }
 
 // InsertOperation is a method specification for insert operations
@@ -30,12 +31,22 @@ type InsertOperation struct {
 	Mode QueryMode
 }
 
+// Name returns "Insert" operation name
+func (o InsertOperation) Name() string {
+	return "Insert"
+}
+
 // FindOperation is a method specification for find operations
 type FindOperation struct {
 	Mode  QueryMode
 	Query QuerySpec
 }
 
+// Name returns "Find" operation name
+func (o FindOperation) Name() string {
+	return "Find"
+}
+
 // UpdateOperation is a method specification for update operations
 type UpdateOperation struct {
 	Fields []UpdateField
@@ -43,6 +54,11 @@ type UpdateOperation struct {
 	Query  QuerySpec
 }
 
+// Name returns "Update" operation name
+func (o UpdateOperation) Name() string {
+	return "Update"
+}
+
 // UpdateField stores mapping between field name in the model and the parameter index
 type UpdateField struct {
 	Name       string
@@ -55,7 +71,17 @@ type DeleteOperation struct {
 	Query QuerySpec
 }
 
+// Name returns "Delete" operation name
+func (o DeleteOperation) Name() string {
+	return "Delete"
+}
+
 // CountOperation is a method specification for count operations
 type CountOperation struct {
 	Query QuerySpec
 }
+
+// Name returns "Count" operation name
+func (o CountOperation) Name() string {
+	return "Count"
+}

internal/spec/models_test.go

@@ -0,0 +1,45 @@
+package spec_test
+
+import (
+	"testing"
+
+	"github.com/sunboyy/repogen/internal/spec"
+)
+
+type OperationTestCase struct {
+	Operation    spec.Operation
+	ExpectedName string
+}
+
+func TestOperationName(t *testing.T) {
+	testTable := []OperationTestCase{
+		{
+			Operation:    spec.InsertOperation{},
+			ExpectedName: "Insert",
+		},
+		{
+			Operation:    spec.FindOperation{},
+			ExpectedName: "Find",
+		},
+		{
+			Operation:    spec.UpdateOperation{},
+			ExpectedName: "Update",
+		},
+		{
+			Operation:    spec.DeleteOperation{},
+			ExpectedName: "Delete",
+		},
+		{
+			Operation:    spec.CountOperation{},
+			ExpectedName: "Count",
+		},
+	}
+
+	for _, testCase := range testTable {
+		t.Run(testCase.ExpectedName, func(t *testing.T) {
+			if testCase.Operation.Name() != testCase.ExpectedName {
+				t.Errorf("Expected = %v\nReceived = %v", testCase.ExpectedName, testCase.Operation.Name())
+			}
+		})
+	}
+}

internal/spec/parser.go

@@ -48,7 +48,7 @@ func (p interfaceMethodParser) parseMethod() (Operation, error) {
 	case "Count":
 		return p.parseCountOperation(methodNameTokens[1:])
 	}
-	return nil, UnknownOperationError
+	return nil, NewUnknownOperationError(methodNameTokens[0])
 }
 
 func (p interfaceMethodParser) parseInsertOperation(tokens []string) (Operation, error) {
@@ -202,7 +202,7 @@ func (p interfaceMethodParser) parseUpdateOperation(tokens []string) (Operation,
 	for _, field := range fields {
 		structField, ok := p.StructModel.Fields.ByName(field.Name)
 		if !ok {
-			return nil, StructFieldNotFoundError
+			return nil, NewStructFieldNotFoundError(field.Name)
 		}
 
 		if structField.Type != p.Method.Params[field.ParamIndex].Type {
@@ -340,7 +340,7 @@ func (p interfaceMethodParser) validateQueryFromParams(params []code.Param, quer
 	for _, predicate := range querySpec.Predicates {
 		structField, ok := p.StructModel.Fields.ByName(predicate.Field)
 		if !ok {
-			return StructFieldNotFoundError
+			return NewStructFieldNotFoundError(predicate.Field)
 		}
 
 		for i := 0; i < predicate.Comparator.NumberOfArguments(); i++ {

internal/spec/parser_test.go

@@ -850,8 +850,9 @@ func TestParseInterfaceMethod_Invalid(t *testing.T) {
 		Name: "SearchByID",
 	})
 
-	if err != spec.UnknownOperationError {
-		t.Errorf("\nExpected = %v\nReceived = %v", spec.UnknownOperationError, err)
+	expectedError := spec.NewUnknownOperationError("Search")
+	if err != expectedError {
+		t.Errorf("\nExpected = %v\nReceived = %v", expectedError, err)
 	}
 }
 
@@ -1008,7 +1009,7 @@ func TestParseInterfaceMethod_Find_Invalid(t *testing.T) {
 					code.SimpleType("error"),
 				},
 			},
-			ExpectedError: spec.InvalidQueryError,
+			ExpectedError: spec.QueryRequiredError,
 		},
 		{
 			Name: "misplaced operator token (leftmost)",
@@ -1019,7 +1020,7 @@ func TestParseInterfaceMethod_Find_Invalid(t *testing.T) {
 					code.SimpleType("error"),
 				},
 			},
-			ExpectedError: spec.InvalidQueryError,
+			ExpectedError: spec.NewInvalidQueryError([]string{"By", "And", "Gender"}),
 		},
 		{
 			Name: "misplaced operator token (rightmost)",
@@ -1030,7 +1031,7 @@ func TestParseInterfaceMethod_Find_Invalid(t *testing.T) {
 					code.SimpleType("error"),
 				},
 			},
-			ExpectedError: spec.InvalidQueryError,
+			ExpectedError: spec.NewInvalidQueryError([]string{"By", "Gender", "And"}),
 		},
 		{
 			Name: "misplaced operator token (double operator)",
@@ -1041,7 +1042,7 @@ func TestParseInterfaceMethod_Find_Invalid(t *testing.T) {
 					code.SimpleType("error"),
 				},
 			},
-			ExpectedError: spec.InvalidQueryError,
+			ExpectedError: spec.NewInvalidQueryError([]string{"By", "Gender", "And", "And", "City"}),
 		},
 		{
 			Name: "ambiguous query",
@@ -1052,7 +1053,7 @@ func TestParseInterfaceMethod_Find_Invalid(t *testing.T) {
 					code.SimpleType("error"),
 				},
 			},
-			ExpectedError: spec.InvalidQueryError,
+			ExpectedError: spec.NewInvalidQueryError([]string{"By", "Gender", "And", "City", "Or", "Age"}),
 		},
 		{
 			Name: "no context parameter",
@@ -1097,7 +1098,7 @@ func TestParseInterfaceMethod_Find_Invalid(t *testing.T) {
 					code.SimpleType("error"),
 				},
 			},
-			ExpectedError: spec.StructFieldNotFoundError,
+			ExpectedError: spec.NewStructFieldNotFoundError("Country"),
 		},
 		{
 			Name: "mismatched method parameter type",
@@ -1209,7 +1210,7 @@ func TestParseInterfaceMethod_Update_Invalid(t *testing.T) {
 					code.SimpleType("error"),
 				},
 			},
-			ExpectedError: spec.InvalidQueryError,
+			ExpectedError: spec.QueryRequiredError,
 		},
 		{
 			Name: "ambiguous query",
@@ -1220,7 +1221,7 @@ func TestParseInterfaceMethod_Update_Invalid(t *testing.T) {
 					code.SimpleType("error"),
 				},
 			},
-			ExpectedError: spec.InvalidQueryError,
+			ExpectedError: spec.NewInvalidQueryError([]string{"By", "ID", "And", "Username", "Or", "Gender"}),
 		},
 		{
 			Name: "no context parameter",
@@ -1251,7 +1252,7 @@ func TestParseInterfaceMethod_Update_Invalid(t *testing.T) {
 					code.SimpleType("error"),
 				},
 			},
-			ExpectedError: spec.StructFieldNotFoundError,
+			ExpectedError: spec.NewStructFieldNotFoundError("Country"),
 		},
 		{
 			Name: "struct field does not match parameter in update fields",
@@ -1343,7 +1344,7 @@ func TestParseInterfaceMethod_Delete_Invalid(t *testing.T) {
 					code.SimpleType("error"),
 				},
 			},
-			ExpectedError: spec.InvalidQueryError,
+			ExpectedError: spec.QueryRequiredError,
 		},
 		{
 			Name: "misplaced operator token (leftmost)",
@@ -1354,7 +1355,7 @@ func TestParseInterfaceMethod_Delete_Invalid(t *testing.T) {
 					code.SimpleType("error"),
 				},
 			},
-			ExpectedError: spec.InvalidQueryError,
+			ExpectedError: spec.NewInvalidQueryError([]string{"By", "And", "Gender"}),
 		},
 		{
 			Name: "misplaced operator token (rightmost)",
@@ -1365,7 +1366,7 @@ func TestParseInterfaceMethod_Delete_Invalid(t *testing.T) {
 					code.SimpleType("error"),
 				},
 			},
-			ExpectedError: spec.InvalidQueryError,
+			ExpectedError: spec.NewInvalidQueryError([]string{"By", "Gender", "And"}),
 		},
 		{
 			Name: "misplaced operator token (double operator)",
@@ -1376,7 +1377,7 @@ func TestParseInterfaceMethod_Delete_Invalid(t *testing.T) {
 					code.SimpleType("error"),
 				},
 			},
-			ExpectedError: spec.InvalidQueryError,
+			ExpectedError: spec.NewInvalidQueryError([]string{"By", "Gender", "And", "And", "City"}),
 		},
 		{
 			Name: "ambiguous query",
@@ -1387,7 +1388,7 @@ func TestParseInterfaceMethod_Delete_Invalid(t *testing.T) {
 					code.SimpleType("error"),
 				},
 			},
-			ExpectedError: spec.InvalidQueryError,
+			ExpectedError: spec.NewInvalidQueryError([]string{"By", "Gender", "And", "City", "Or", "Age"}),
 		},
 		{
 			Name: "no context parameter",
@@ -1432,7 +1433,7 @@ func TestParseInterfaceMethod_Delete_Invalid(t *testing.T) {
 					code.SimpleType("error"),
 				},
 			},
-			ExpectedError: spec.StructFieldNotFoundError,
+			ExpectedError: spec.NewStructFieldNotFoundError("Country"),
 		},
 		{
 			Name: "mismatched method parameter type",
@@ -1522,7 +1523,7 @@ func TestParseInterfaceMethod_Count_Invalid(t *testing.T) {
 					code.SimpleType("error"),
 				},
 			},
-			ExpectedError: spec.InvalidQueryError,
+			ExpectedError: spec.QueryRequiredError,
 		},
 		{
 			Name: "invalid query",
@@ -1536,7 +1537,7 @@ func TestParseInterfaceMethod_Count_Invalid(t *testing.T) {
 					code.SimpleType("error"),
 				},
 			},
-			ExpectedError: spec.InvalidQueryError,
+			ExpectedError: spec.NewInvalidQueryError([]string{"By"}),
 		},
 		{
 			Name: "context parameter not provided",
@@ -1593,7 +1594,7 @@ func TestParseInterfaceMethod_Count_Invalid(t *testing.T) {
 					code.SimpleType("error"),
 				},
 			},
-			ExpectedError: spec.StructFieldNotFoundError,
+			ExpectedError: spec.NewStructFieldNotFoundError("Country"),
 		},
 	}
 

internal/spec/query.go

@@ -95,11 +95,12 @@ func (t predicateToken) ToPredicate(paramIndex int) Predicate {
 	return Predicate{Field: strings.Join(t, ""), Comparator: ComparatorEqual, ParamIndex: paramIndex}
 }
 
-func parseQuery(tokens []string, paramIndex int) (QuerySpec, error) {
-	if len(tokens) == 0 {
-		return QuerySpec{}, InvalidQueryError
+func parseQuery(rawTokens []string, paramIndex int) (QuerySpec, error) {
+	if len(rawTokens) == 0 {
+		return QuerySpec{}, QueryRequiredError
 	}
 
+	tokens := rawTokens
 	if len(tokens) == 1 && tokens[0] == "All" {
 		return QuerySpec{}, nil
 	}
@@ -112,7 +113,7 @@ func parseQuery(tokens []string, paramIndex int) (QuerySpec, error) {
 	}
 
 	if len(tokens) == 0 || tokens[0] == "And" || tokens[0] == "Or" {
-		return QuerySpec{}, InvalidQueryError
+		return QuerySpec{}, NewInvalidQueryError(rawTokens)
 	}
 
 	var operator Operator
@@ -122,7 +123,7 @@ func parseQuery(tokens []string, paramIndex int) (QuerySpec, error) {
 		if token != "And" && token != "Or" {
 			aggregatedToken = append(aggregatedToken, token)
 		} else if len(aggregatedToken) == 0 {
-			return QuerySpec{}, InvalidQueryError
+			return QuerySpec{}, NewInvalidQueryError(rawTokens)
 		} else if token == "And" && operator != OperatorOr {
 			operator = OperatorAnd
 			predicate := aggregatedToken.ToPredicate(paramIndex)
@@ -136,11 +137,11 @@ func parseQuery(tokens []string, paramIndex int) (QuerySpec, error) {
 			paramIndex += predicate.Comparator.NumberOfArguments()
 			aggregatedToken = predicateToken{}
 		} else {
-			return QuerySpec{}, InvalidQueryError
+			return QuerySpec{}, NewInvalidQueryError(rawTokens)
 		}
 	}
 	if len(aggregatedToken) == 0 {
-		return QuerySpec{}, InvalidQueryError
+		return QuerySpec{}, NewInvalidQueryError(rawTokens)
 	}
 	predicates = append(predicates, aggregatedToken.ToPredicate(paramIndex))