allow to expect prepared statement to be closed, closes #89

Author: l3pp4rd

README.md

@@ -190,6 +190,8 @@ It only asserts that argument is of `time.Time` type.
 
 ## Change Log
 
+- **2017-09-01** - it is now possible to expect that prepared statement will be closed,
+  using **ExpectedPrepare.WillBeClosed**.
 - **2017-02-09** - implemented support for **go1.8** features. **Rows** interface was changed to struct
   but contains all methods as before and should maintain backwards compatibility. **ExpectedQuery.WillReturnRows** may now
   accept multiple row sets.

expectations.go

@@ -252,11 +252,13 @@ func (e *ExpectedExec) WillReturnResult(result driver.Result) *ExpectedExec {
 // Returned by *Sqlmock.ExpectPrepare.
 type ExpectedPrepare struct {
 	commonExpectation
-	mock      *sqlmock
-	sqlRegex  *regexp.Regexp
-	statement driver.Stmt
-	closeErr  error
-	delay     time.Duration
+	mock         *sqlmock
+	sqlRegex     *regexp.Regexp
+	statement    driver.Stmt
+	closeErr     error
+	mustBeClosed bool
+	wasClosed    bool
+	delay        time.Duration
 }
 
 // WillReturnError allows to set an error for the expected *sql.DB.Prepare or *sql.Tx.Prepare action.
@@ -278,6 +280,13 @@ func (e *ExpectedPrepare) WillDelayFor(duration time.Duration) *ExpectedPrepare
 	return e
 }
 
+// WillBeClosed expects this prepared statement to
+// be closed.
+func (e *ExpectedPrepare) WillBeClosed() *ExpectedPrepare {
+	e.mustBeClosed = true
+	return e
+}
+
 // ExpectQuery allows to expect Query() or QueryRow() on this prepared statement.
 // this method is convenient in order to prevent duplicating sql query string matching.
 func (e *ExpectedPrepare) ExpectQuery() *ExpectedQuery {

sqlmock.go

@@ -154,6 +154,13 @@ func (c *sqlmock) ExpectationsWereMet() error {
 		if !e.fulfilled() {
 			return fmt.Errorf("there is a remaining expectation which was not matched: %s", e)
 		}
+
+		// for expected prepared statement check whether it was closed if expected
+		if prep, ok := e.(*ExpectedPrepare); ok {
+			if prep.mustBeClosed && !prep.wasClosed {
+				return fmt.Errorf("expected prepared statement to be closed, but it was not: %s", prep)
+			}
+		}
 	}
 	return nil
 }
@@ -302,7 +309,7 @@ func (c *sqlmock) Prepare(query string) (driver.Stmt, error) {
 	}
 
 	time.Sleep(ex.delay)
-	return &statement{c, query, ex.closeErr}, nil
+	return &statement{c, ex, query}, nil
 }
 
 func (c *sqlmock) prepare(query string) (*ExpectedPrepare, error) {

sqlmock_test.go

@@ -1033,3 +1033,33 @@ func TestExpectedBeginOrder(t *testing.T) {
 		t.Error("an error was expected when calling close, but got none")
 	}
 }
+
+func TestPreparedStatementCloseExpectation(t *testing.T) {
+	// Open new mock database
+	db, mock, err := New()
+	if err != nil {
+		fmt.Println("error creating mock database")
+		return
+	}
+	defer db.Close()
+
+	ep := mock.ExpectPrepare("INSERT INTO ORDERS").WillBeClosed()
+	ep.ExpectExec().WillReturnResult(NewResult(1, 1))
+
+	stmt, err := db.Prepare("INSERT INTO ORDERS(ID, STATUS) VALUES (?, ?)")
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	if _, err := stmt.Exec(1, "Hello"); err != nil {
+		t.Fatal(err)
+	}
+
+	if err := stmt.Close(); err != nil {
+		t.Fatal(err)
+	}
+
+	if err := mock.ExpectationsWereMet(); err != nil {
+		t.Errorf("there were unfulfilled expections: %s", err)
+	}
+}

statement.go

@@ -6,12 +6,13 @@ import (
 
 type statement struct {
 	conn  *sqlmock
+	ex    *ExpectedPrepare
 	query string
-	err   error
 }
 
 func (stmt *statement) Close() error {
-	return stmt.err
+	stmt.ex.wasClosed = true
+	return stmt.ex.closeErr
 }
 
 func (stmt *statement) NumInput() int {