documentation update based on lint

README.md

@@ -1,10 +1,11 @@
 [![Build Status](https://travis-ci.org/DATA-DOG/go-sqlmock.png)](https://travis-ci.org/DATA-DOG/go-sqlmock)
+[![GoDoc](https://godoc.org/github.com/DATA-DOG/go-sqlmock?status.png)](https://godoc.org/github.com/DATA-DOG/go-sqlmock)
 
 # Sql driver mock for Golang
 
 This is a **mock** driver as **database/sql/driver** which is very flexible and pragmatic to
 manage and mock expected queries. All the expectations should be met and all queries and actions
-triggered should be mocked in order to pass a test. See exported [api on godoc](http://godoc.org/github.com/DATA-DOG/go-sqlmock)
+triggered should be mocked in order to pass a test.
 
 ## Install
 
@@ -289,7 +290,7 @@ to compare them correctly, this may be improved.
 
 ## Documentation
 
-See it on [godoc](http://godoc.org/github.com/DATA-DOG/go-sqlmock)
+Visit [godoc](http://godoc.org/github.com/DATA-DOG/go-sqlmock)
 
 ## TODO
 

connection.go

@@ -10,13 +10,13 @@ type conn struct {
 	active       expectation
 }
 
-// closes a mock database driver connection. It should
+// Close a mock database driver connection. It should
 // be always called to ensure that all expectations
-// were met successfully
+// were met successfully. Returns error if there is any
 func (c *conn) Close() (err error) {
 	for _, e := range mock.conn.expectations {
 		if !e.fulfilled() {
-			err = fmt.Errorf("There is a remaining expectation %T which was not matched yet", e)
+			err = fmt.Errorf("there is a remaining expectation %T which was not matched yet", e)
 			break
 		}
 	}
@@ -28,12 +28,12 @@ func (c *conn) Close() (err error) {
 func (c *conn) Begin() (driver.Tx, error) {
 	e := c.next()
 	if e == nil {
-		return nil, fmt.Errorf("All expectations were already fulfilled, call to Begin transaction was not expected")
+		return nil, fmt.Errorf("all expectations were already fulfilled, call to begin transaction was not expected")
 	}
 
 	etb, ok := e.(*expectedBegin)
 	if !ok {
-		return nil, fmt.Errorf("Call to Begin transaction, was not expected, next expectation is %T as %+v", e, e)
+		return nil, fmt.Errorf("call to begin transaction, was not expected, next expectation is %T as %+v", e, e)
 	}
 	etb.triggered = true
 	return &transaction{c}, etb.err
@@ -53,12 +53,12 @@ func (c *conn) Exec(query string, args []driver.Value) (driver.Result, error) {
 	e := c.next()
 	query = stripQuery(query)
 	if e == nil {
-		return nil, fmt.Errorf("All expectations were already fulfilled, call to Exec '%s' query with args %+v was not expected", query, args)
+		return nil, fmt.Errorf("all expectations were already fulfilled, call to exec '%s' query with args %+v was not expected", query, args)
 	}
 
 	eq, ok := e.(*expectedExec)
 	if !ok {
-		return nil, fmt.Errorf("Call to Exec query '%s' with args %+v, was not expected, next expectation is %T as %+v", query, args, e, e)
+		return nil, fmt.Errorf("call to exec query '%s' with args %+v, was not expected, next expectation is %T as %+v", query, args, e, e)
 	}
 
 	eq.triggered = true
@@ -67,15 +67,15 @@ func (c *conn) Exec(query string, args []driver.Value) (driver.Result, error) {
 	}
 
 	if eq.result == nil {
-		return nil, fmt.Errorf("Exec query '%s' with args %+v, must return a database/sql/driver.Result, but it was not set for expectation %T as %+v", query, args, eq, eq)
+		return nil, fmt.Errorf("exec query '%s' with args %+v, must return a database/sql/driver.result, but it was not set for expectation %T as %+v", query, args, eq, eq)
 	}
 
 	if !eq.queryMatches(query) {
-		return nil, fmt.Errorf("Exec query '%s', does not match regex '%s'", query, eq.sqlRegex.String())
+		return nil, fmt.Errorf("exec query '%s', does not match regex '%s'", query, eq.sqlRegex.String())
 	}
 
 	if !eq.argsMatches(args) {
-		return nil, fmt.Errorf("Exec query '%s', args %+v does not match expected %+v", query, args, eq.args)
+		return nil, fmt.Errorf("exec query '%s', args %+v does not match expected %+v", query, args, eq.args)
 	}
 
 	return eq.result, nil
@@ -89,12 +89,12 @@ func (c *conn) Query(query string, args []driver.Value) (driver.Rows, error) {
 	e := c.next()
 	query = stripQuery(query)
 	if e == nil {
-		return nil, fmt.Errorf("All expectations were already fulfilled, call to Query '%s' with args %+v was not expected", query, args)
+		return nil, fmt.Errorf("all expectations were already fulfilled, call to query '%s' with args %+v was not expected", query, args)
 	}
 
 	eq, ok := e.(*expectedQuery)
 	if !ok {
-		return nil, fmt.Errorf("Call to Query '%s' with args %+v, was not expected, next expectation is %T as %+v", query, args, e, e)
+		return nil, fmt.Errorf("call to query '%s' with args %+v, was not expected, next expectation is %T as %+v", query, args, e, e)
 	}
 
 	eq.triggered = true
@@ -103,15 +103,15 @@ func (c *conn) Query(query string, args []driver.Value) (driver.Rows, error) {
 	}
 
 	if eq.rows == nil {
-		return nil, fmt.Errorf("Query '%s' with args %+v, must return a database/sql/driver.Rows, but it was not set for expectation %T as %+v", query, args, eq, eq)
+		return nil, fmt.Errorf("query '%s' with args %+v, must return a database/sql/driver.rows, but it was not set for expectation %T as %+v", query, args, eq, eq)
 	}
 
 	if !eq.queryMatches(query) {
-		return nil, fmt.Errorf("Query '%s', does not match regex [%s]", query, eq.sqlRegex.String())
+		return nil, fmt.Errorf("query '%s', does not match regex [%s]", query, eq.sqlRegex.String())
 	}
 
 	if !eq.argsMatches(args) {
-		return nil, fmt.Errorf("Query '%s', args %+v does not match expected %+v", query, args, eq.args)
+		return nil, fmt.Errorf("query '%s', args %+v does not match expected %+v", query, args, eq.args)
 	}
 
 	return eq.rows, nil

expectations_test.go

@@ -13,22 +13,22 @@ func TestQueryExpectationArgComparison(t *testing.T) {
 	against := []driver.Value{5}
 
 	if e.argsMatches(against) {
-		t.Error("Arguments should not match, since the size is not the same")
+		t.Error("arguments should not match, since the size is not the same")
 	}
 
 	against = []driver.Value{3, "str"}
 	if e.argsMatches(against) {
-		t.Error("Arguments should not match, since the first argument (int value) is different")
+		t.Error("arguments should not match, since the first argument (int value) is different")
 	}
 
 	against = []driver.Value{5, "st"}
 	if e.argsMatches(against) {
-		t.Error("Arguments should not match, since the second argument (string value) is different")
+		t.Error("arguments should not match, since the second argument (string value) is different")
 	}
 
 	against = []driver.Value{5, "str"}
 	if !e.argsMatches(against) {
-		t.Error("Arguments should match, but it did not")
+		t.Error("arguments should match, but it did not")
 	}
 
 	e.args = []driver.Value{5, time.Now()}
@@ -38,6 +38,6 @@ func TestQueryExpectationArgComparison(t *testing.T) {
 
 	against = []driver.Value{5, tm}
 	if !e.argsMatches(against) {
-		t.Error("Arguments should match (time will be compared only by type), but it did not")
+		t.Error("arguments should match (time will be compared only by type), but it did not")
 	}
 }

result.go

@@ -1,27 +1,30 @@
 package sqlmock
 
+import (
+    "database/sql/driver"
+)
+
 // Result satisfies sql driver Result, which
 // holds last insert id and rows affected
 // by Exec queries
-type Result struct {
-	lastInsertId int64
+type result struct {
+	insertID int64
 	rowsAffected int64
 }
 
-// Creates a new Result for Exec based query mocks
-func NewResult(lastInsertId int64, rowsAffected int64) *Result {
-	return &Result{
-		lastInsertId,
+// NewResult creates a new sql driver Result
+// for Exec based query mocks.
+func NewResult(lastInsertID int64, rowsAffected int64) driver.Result {
+	return &result{
+		lastInsertID,
 		rowsAffected,
 	}
 }
 
-// Retrieve last inserted id
-func (res *Result) LastInsertId() (int64, error) {
-	return res.lastInsertId, nil
+func (r *result) LastInsertId() (int64, error) {
+	return r.insertID, nil
 }
 
-// Retrieve number rows affected
-func (res *Result) RowsAffected() (int64, error) {
-	return res.rowsAffected, nil
+func (r *result) RowsAffected() (int64, error) {
+	return r.rowsAffected, nil
 }

rows.go

@@ -40,8 +40,8 @@ func (r *rows) Next(dest []driver.Value) error {
 	return nil
 }
 
-// Create Rows from CSV string
-// to be used for mocked queries. Satisfies sql driver Rows interface
+// RowsFromCSVString creates Rows from CSV string
+// to be used for mocked queries. Returns sql driver Rows interface
 func RowsFromCSVString(columns []string, s string) driver.Rows {
 	rs := &rows{}
 	rs.cols = columns

sqlmock.go

@@ -85,7 +85,7 @@ func init() {
 	sql.Register("mock", mock)
 }
 
-// Expect transaction to be started
+// ExpectBegin expects transaction to be started
 func ExpectBegin() Mock {
 	e := &expectedBegin{}
 	mock.conn.expectations = append(mock.conn.expectations, e)
@@ -93,7 +93,7 @@ func ExpectBegin() Mock {
 	return mock.conn
 }
 
-// Expect transaction to be commited
+// ExpectCommit expects transaction to be commited
 func ExpectCommit() Mock {
 	e := &expectedCommit{}
 	mock.conn.expectations = append(mock.conn.expectations, e)
@@ -101,7 +101,7 @@ func ExpectCommit() Mock {
 	return mock.conn
 }
 
-// Expect transaction to be rolled back
+// ExpectRollback expects transaction to be rolled back
 func ExpectRollback() Mock {
 	e := &expectedRollback{}
 	mock.conn.expectations = append(mock.conn.expectations, e)
@@ -109,13 +109,13 @@ func ExpectRollback() Mock {
 	return mock.conn
 }
 
-// The expectation will return an error
+// WillReturnError the expectation will return an error
 func (c *conn) WillReturnError(err error) Mock {
 	c.active.setError(err)
 	return c
 }
 
-// Expect database Exec to be triggered, which will match
+// ExpectExec expects database Exec to be triggered, which will match
 // the given query string as a regular expression
 func ExpectExec(sqlRegexStr string) Mock {
 	e := &expectedExec{}
@@ -125,7 +125,7 @@ func ExpectExec(sqlRegexStr string) Mock {
 	return mock.conn
 }
 
-// Expect database Query to be triggered, which will match
+// ExpectQuery database Query to be triggered, which will match
 // the given query string as a regular expression
 func ExpectQuery(sqlRegexStr string) Mock {
 	e := &expectedQuery{}
@@ -136,14 +136,14 @@ func ExpectQuery(sqlRegexStr string) Mock {
 	return mock.conn
 }
 
-// The expectation should be called with given arguments.
+// WithArgs expectation should be called with given arguments.
 // Works with Exec and Query expectations
 func (c *conn) WithArgs(args ...driver.Value) Mock {
 	eq, ok := c.active.(*expectedQuery)
 	if !ok {
 		ee, ok := c.active.(*expectedExec)
 		if !ok {
-			panic(fmt.Sprintf("Arguments may be expected only with query based expectations, current is %T", c.active))
+			panic(fmt.Sprintf("arguments may be expected only with query based expectations, current is %T", c.active))
 		}
 		ee.args = args
 	} else {
@@ -152,23 +152,23 @@ func (c *conn) WithArgs(args ...driver.Value) Mock {
 	return c
 }
 
-// The expectation will return a Result.
+// WillReturnResult expectation will return a Result.
 // Works only with Exec expectations
 func (c *conn) WillReturnResult(result driver.Result) Mock {
 	eq, ok := c.active.(*expectedExec)
 	if !ok {
-		panic(fmt.Sprintf("driver.Result may be returned only by Exec expectations, current is %T", c.active))
+		panic(fmt.Sprintf("driver.result may be returned only by exec expectations, current is %T", c.active))
 	}
 	eq.result = result
 	return c
 }
 
-// The expectation will return Rows.
+// WillReturnRows expectation will return Rows.
 // Works only with Query expectations
 func (c *conn) WillReturnRows(rows driver.Rows) Mock {
 	eq, ok := c.active.(*expectedQuery)
 	if !ok {
-		panic(fmt.Sprintf("driver.Rows may be returned only by Query expectations, current is %T", c.active))
+		panic(fmt.Sprintf("driver.rows may be returned only by query expectations, current is %T", c.active))
 	}
 	eq.rows = rows
 	return c

sqlmock_test.go

@@ -2,14 +2,14 @@ package sqlmock
 
 import (
 	"database/sql"
-	"errors"
+	"fmt"
 	"testing"
 )
 
 func TestMockQuery(t *testing.T) {
 	db, err := sql.Open("mock", "")
 	if err != nil {
-		t.Errorf("An error '%s' was not expected when opening a stub database connection", err)
+		t.Errorf("an error '%s' was not expected when opening a stub database connection", err)
 	}
 
 	rs := RowsFromCSVString([]string{"id", "title"}, "5,hello world")
@@ -20,11 +20,11 @@ func TestMockQuery(t *testing.T) {
 
 	rows, err := db.Query("SELECT (.+) FROM articles WHERE id = ?", 5)
 	if err != nil {
-		t.Errorf("Error '%s' was not expected while retrieving mock rows", err)
+		t.Errorf("error '%s' was not expected while retrieving mock rows", err)
 	}
 	defer rows.Close()
 	if !rows.Next() {
-		t.Error("It must have had one row as result, but got empty result set instead")
+		t.Error("it must have had one row as result, but got empty result set instead")
 	}
 
 	var id int
@@ -32,26 +32,26 @@ func TestMockQuery(t *testing.T) {
 
 	err = rows.Scan(&id, &title)
 	if err != nil {
-		t.Errorf("Error '%s' was not expected while trying to scan row", err)
+		t.Errorf("error '%s' was not expected while trying to scan row", err)
 	}
 
 	if id != 5 {
-		t.Errorf("Expected mocked id to be 5, but got %d instead", id)
+		t.Errorf("expected mocked id to be 5, but got %d instead", id)
 	}
 
 	if title != "hello world" {
-		t.Errorf("Expected mocked title to be 'hello world', but got '%s' instead", title)
+		t.Errorf("expected mocked title to be 'hello world', but got '%s' instead", title)
 	}
 
 	if err = db.Close(); err != nil {
-		t.Errorf("Error '%s' was not expected while closing the database", err)
+		t.Errorf("error '%s' was not expected while closing the database", err)
 	}
 }
 
 func TestTransactionExpectations(t *testing.T) {
 	db, err := sql.Open("mock", "")
 	if err != nil {
-		t.Errorf("An error '%s' was not expected when opening a stub database connection", err)
+		t.Errorf("an error '%s' was not expected when opening a stub database connection", err)
 	}
 
 	// begin and commit
@@ -60,12 +60,12 @@ func TestTransactionExpectations(t *testing.T) {
 
 	tx, err := db.Begin()
 	if err != nil {
-		t.Errorf("An error '%s' was not expected when beginning a transaction", err)
+		t.Errorf("an error '%s' was not expected when beginning a transaction", err)
 	}
 
 	err = tx.Commit()
 	if err != nil {
-		t.Errorf("An error '%s' was not expected when commiting a transaction", err)
+		t.Errorf("an error '%s' was not expected when commiting a transaction", err)
 	}
 
 	// begin and rollback
@@ -74,31 +74,31 @@ func TestTransactionExpectations(t *testing.T) {
 
 	tx, err = db.Begin()
 	if err != nil {
-		t.Errorf("An error '%s' was not expected when beginning a transaction", err)
+		t.Errorf("an error '%s' was not expected when beginning a transaction", err)
 	}
 
 	err = tx.Rollback()
 	if err != nil {
-		t.Errorf("An error '%s' was not expected when rolling back a transaction", err)
+		t.Errorf("an error '%s' was not expected when rolling back a transaction", err)
 	}
 
 	// begin with an error
-	ExpectBegin().WillReturnError(errors.New("Some err"))
+	ExpectBegin().WillReturnError(fmt.Errorf("some err"))
 
 	tx, err = db.Begin()
 	if err == nil {
-		t.Error("An error was expected when beginning a transaction, but got none")
+		t.Error("an error was expected when beginning a transaction, but got none")
 	}
 
 	if err = db.Close(); err != nil {
-		t.Errorf("Error '%s' was not expected while closing the database", err)
+		t.Errorf("error '%s' was not expected while closing the database", err)
 	}
 }
 
 func TestPreparedQueryExecutions(t *testing.T) {
 	db, err := sql.Open("mock", "")
 	if err != nil {
-		t.Errorf("An error '%s' was not expected when opening a stub database connection", err)
+		t.Errorf("an error '%s' was not expected when opening a stub database connection", err)
 	}
 
 	rs1 := RowsFromCSVString([]string{"id", "title"}, "5,hello world")
@@ -113,7 +113,7 @@ func TestPreparedQueryExecutions(t *testing.T) {
 
 	stmt, err := db.Prepare("SELECT (.+) FROM articles WHERE id = ?")
 	if err != nil {
-		t.Errorf("Error '%s' was not expected while creating a prepared statement", err)
+		t.Errorf("error '%s' was not expected while creating a prepared statement", err)
 	}
 
 	var id int
@@ -121,44 +121,44 @@ func TestPreparedQueryExecutions(t *testing.T) {
 
 	err = stmt.QueryRow(5).Scan(&id, &title)
 	if err != nil {
-		t.Errorf("Error '%s' was not expected querying row from statement and scanning", err)
+		t.Errorf("error '%s' was not expected querying row from statement and scanning", err)
 	}
 
 	if id != 5 {
-		t.Errorf("Expected mocked id to be 5, but got %d instead", id)
+		t.Errorf("expected mocked id to be 5, but got %d instead", id)
 	}
 
 	if title != "hello world" {
-		t.Errorf("Expected mocked title to be 'hello world', but got '%s' instead", title)
+		t.Errorf("expected mocked title to be 'hello world', but got '%s' instead", title)
 	}
 
 	err = stmt.QueryRow(2).Scan(&id, &title)
 	if err != nil {
-		t.Errorf("Error '%s' was not expected querying row from statement and scanning", err)
+		t.Errorf("error '%s' was not expected querying row from statement and scanning", err)
 	}
 
 	if id != 2 {
-		t.Errorf("Expected mocked id to be 2, but got %d instead", id)
+		t.Errorf("expected mocked id to be 2, but got %d instead", id)
 	}
 
 	if title != "whoop" {
-		t.Errorf("Expected mocked title to be 'whoop', but got '%s' instead", title)
+		t.Errorf("expected mocked title to be 'whoop', but got '%s' instead", title)
 	}
 
 	if err = db.Close(); err != nil {
-		t.Errorf("Error '%s' was not expected while closing the database", err)
+		t.Errorf("error '%s' was not expected while closing the database", err)
 	}
 }
 
 func TestUnexpectedOperations(t *testing.T) {
 	db, err := sql.Open("mock", "")
 	if err != nil {
-		t.Errorf("An error '%s' was not expected when opening a stub database connection", err)
+		t.Errorf("an error '%s' was not expected when opening a stub database connection", err)
 	}
 
 	stmt, err := db.Prepare("SELECT (.+) FROM articles WHERE id = ?")
 	if err != nil {
-		t.Errorf("Error '%s' was not expected while creating a prepared statement", err)
+		t.Errorf("error '%s' was not expected while creating a prepared statement", err)
 	}
 
 	var id int
@@ -166,21 +166,21 @@ func TestUnexpectedOperations(t *testing.T) {
 
 	err = stmt.QueryRow(5).Scan(&id, &title)
 	if err == nil {
-		t.Error("Error was expected querying row, since there was no such expectation")
+		t.Error("error was expected querying row, since there was no such expectation")
 	}
 
 	ExpectRollback()
 
 	err = db.Close()
 	if err == nil {
-		t.Error("Error was expected while closing the database, expectation was not fulfilled", err)
+		t.Error("error was expected while closing the database, expectation was not fulfilled", err)
 	}
 }
 
 func TestWrongExpectations(t *testing.T) {
 	db, err := sql.Open("mock", "")
 	if err != nil {
-		t.Errorf("An error '%s' was not expected when opening a stub database connection", err)
+		t.Errorf("an error '%s' was not expected when opening a stub database connection", err)
 	}
 
 	ExpectBegin()
@@ -190,12 +190,12 @@ func TestWrongExpectations(t *testing.T) {
 		WithArgs(5).
 		WillReturnRows(rs1)
 
-	ExpectCommit().WillReturnError(errors.New("Deadlock occured"))
+	ExpectCommit().WillReturnError(fmt.Errorf("deadlock occured"))
 	ExpectRollback() // won't be triggered
 
 	stmt, err := db.Prepare("SELECT (.+) FROM articles WHERE id = ? FOR UPDATE")
 	if err != nil {
-		t.Errorf("Error '%s' was not expected while creating a prepared statement", err)
+		t.Errorf("error '%s' was not expected while creating a prepared statement", err)
 	}
 
 	var id int
@@ -203,35 +203,35 @@ func TestWrongExpectations(t *testing.T) {
 
 	err = stmt.QueryRow(5).Scan(&id, &title)
 	if err == nil {
-		t.Error("Error was expected while querying row, since there Begin transaction expectation is not fulfilled")
+		t.Error("error was expected while querying row, since there begin transaction expectation is not fulfilled")
 	}
 
 	// lets go around and start transaction
 	tx, err := db.Begin()
 	if err != nil {
-		t.Errorf("An error '%s' was not expected when beginning a transaction", err)
+		t.Errorf("an error '%s' was not expected when beginning a transaction", err)
 	}
 
 	err = stmt.QueryRow(5).Scan(&id, &title)
 	if err != nil {
-		t.Errorf("Error '%s' was not expected while querying row, since transaction was started", err)
+		t.Errorf("error '%s' was not expected while querying row, since transaction was started", err)
 	}
 
 	err = tx.Commit()
 	if err == nil {
-		t.Error("A deadlock error was expected when commiting a transaction", err)
+		t.Error("a deadlock error was expected when commiting a transaction", err)
 	}
 
 	err = db.Close()
 	if err == nil {
-		t.Error("Error was expected while closing the database, expectation was not fulfilled", err)
+		t.Error("error was expected while closing the database, expectation was not fulfilled", err)
 	}
 }
 
 func TestExecExpectations(t *testing.T) {
 	db, err := sql.Open("mock", "")
 	if err != nil {
-		t.Errorf("An error '%s' was not expected when opening a stub database connection", err)
+		t.Errorf("an error '%s' was not expected when opening a stub database connection", err)
 	}
 
 	result := NewResult(1, 1)
@@ -241,28 +241,28 @@ func TestExecExpectations(t *testing.T) {
 
 	res, err := db.Exec("INSERT INTO articles (title) VALUES (?)", "hello")
 	if err != nil {
-		t.Errorf("Error '%s' was not expected, while inserting a row", err)
+		t.Errorf("error '%s' was not expected, while inserting a row", err)
 	}
 
 	id, err := res.LastInsertId()
 	if err != nil {
-		t.Errorf("Error '%s' was not expected, while getting a last insert id", err)
+		t.Errorf("error '%s' was not expected, while getting a last insert id", err)
 	}
 
 	affected, err := res.RowsAffected()
 	if err != nil {
-		t.Errorf("Error '%s' was not expected, while getting affected rows", err)
+		t.Errorf("error '%s' was not expected, while getting affected rows", err)
 	}
 
 	if id != 1 {
-		t.Errorf("Expected last insert id to be 1, but got %d instead", id)
+		t.Errorf("expected last insert id to be 1, but got %d instead", id)
 	}
 
 	if affected != 1 {
-		t.Errorf("Expected affected rows to be 1, but got %d instead", affected)
+		t.Errorf("expected affected rows to be 1, but got %d instead", affected)
 	}
 
 	if err = db.Close(); err != nil {
-		t.Errorf("Error '%s' was not expected while closing the database", err)
+		t.Errorf("error '%s' was not expected while closing the database", err)
 	}
 }

transaction.go

@@ -1,7 +1,6 @@
 package sqlmock
 
 import (
-	"errors"
 	"fmt"
 )
 
@@ -12,12 +11,12 @@ type transaction struct {
 func (tx *transaction) Commit() error {
 	e := tx.conn.next()
 	if e == nil {
-		return errors.New("All expectations were already fulfilled, call to Commit transaction was not expected")
+		return fmt.Errorf("all expectations were already fulfilled, call to commit transaction was not expected")
 	}
 
 	etc, ok := e.(*expectedCommit)
 	if !ok {
-		return errors.New(fmt.Sprintf("Call to Commit transaction, was not expected, next expectation was %v", e))
+		return fmt.Errorf("call to commit transaction, was not expected, next expectation was %v", e)
 	}
 	etc.triggered = true
 	return etc.err
@@ -26,12 +25,12 @@ func (tx *transaction) Commit() error {
 func (tx *transaction) Rollback() error {
 	e := tx.conn.next()
 	if e == nil {
-		return errors.New("All expectations were already fulfilled, call to Rollback transaction was not expected")
+		return fmt.Errorf("all expectations were already fulfilled, call to rollback transaction was not expected")
 	}
 
 	etr, ok := e.(*expectedRollback)
 	if !ok {
-		return errors.New(fmt.Sprintf("Call to Rollback transaction, was not expected, next expectation was %v", e))
+		return fmt.Errorf("call to rollback transaction, was not expected, next expectation was %v", e)
 	}
 	etr.triggered = true
 	return etr.err