mention about escaping characters for regular expressions #6

README.md

@@ -277,7 +277,16 @@ Instead of result we can return error..
 ``` go
 sqlmock.ExpectQuery("SELECT (.*) FROM orders").
 	WithArgs("string value").
-	WillReturnResult(sqlmock.NewResult(0, 1))
+	WillReturnRows(sqlmock.NewRows([]string{"col"}).AddRow("val"))
+```
+
+**NOTE:** it matches a regular expression. Some regex special characters must be escaped if you want to match them.
+For example if we want to match a subselect:
+
+``` go
+sqlmock.ExpectQuery("SELECT (.*) FROM orders WHERE id IN \\(SELECT id FROM finished WHERE status = 1\\)").
+	WithArgs("string value").
+	WillReturnRows(sqlmock.NewRows([]string{"col"}).AddRow("val"))
 ```
 
 **WithArgs** expectation, compares values based on their type, for usual values like **string, float, int**

expectations_test.go

@@ -2,6 +2,7 @@ package sqlmock
 
 import (
 	"database/sql/driver"
+	"regexp"
 	"testing"
 	"time"
 )
@@ -57,3 +58,16 @@ func TestQueryExpectationArgComparison(t *testing.T) {
 		t.Error("arguments should match, but it did not")
 	}
 }
+
+func TestQueryExpectationSqlMatch(t *testing.T) {
+	e := &expectedExec{}
+	e.sqlRegex = regexp.MustCompile("SELECT x FROM")
+	if !e.queryMatches("SELECT x FROM someting") {
+		t.Errorf("Sql must have matched the query")
+	}
+
+	e.sqlRegex = regexp.MustCompile("SELECT COUNT\\(x\\) FROM")
+	if !e.queryMatches("SELECT COUNT(x) FROM someting") {
+		t.Errorf("Sql must have matched the query")
+	}
+}