Remove 0 bytes when sanitizing identifiers

fixes #562

conn.go

@@ -307,7 +307,8 @@ type Identifier []string
 func (ident Identifier) Sanitize() string {
 	parts := make([]string, len(ident))
 	for i := range ident {
-		parts[i] = `"` + strings.Replace(ident[i], `"`, `""`, -1) + `"`
+		s := strings.Replace(ident[i], string([]byte{0}), "", -1)
+		parts[i] = `"` + strings.Replace(s, `"`, `""`, -1) + `"`
 	}
 	return strings.Join(parts, ".")
 }

conn_test.go

@@ -84,7 +84,6 @@ func TestConnect(t *testing.T) {
 	}
 }
 
-
 func TestConnectWithMultiHost(t *testing.T) {
 	t.Parallel()
 
@@ -129,7 +128,6 @@ func TestConnectWithMultiHost(t *testing.T) {
 	}
 }
 
-
 func TestConnectWithMultiHostWritable(t *testing.T) {
 	t.Parallel()
 
@@ -2319,6 +2317,24 @@ func TestSetLogLevel(t *testing.T) {
 	}
 }
 
+func TestIdentifierSanitizeNullSentToServer(t *testing.T) {
+	t.Parallel()
+
+	conn := mustConnect(t, *defaultConnConfig)
+	defer closeConn(t, conn)
+
+	ident := pgx.Identifier{"foo" + string([]byte{0}) + "bar"}
+
+	var n int64
+	err := conn.QueryRow(`select 1 as ` + ident.Sanitize()).Scan(&n)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if n != 1 {
+		t.Fatal("unexpected n")
+	}
+}
+
 func TestIdentifierSanitize(t *testing.T) {
 	t.Parallel()
 
@@ -2346,6 +2362,10 @@ func TestIdentifierSanitize(t *testing.T) {
 			ident:    pgx.Identifier{`you should " not do this`, `please don't`},
 			expected: `"you should "" not do this"."please don't"`,
 		},
+		{
+			ident:    pgx.Identifier{`you should ` + string([]byte{0}) + `not do this`},
+			expected: `"you should not do this"`,
+		},
 	}
 
 	for i, tt := range tests {