[tracker/wip/carlosg/escape-single-quotes] libtracker-sparql: Escape single quotes

[Carlos Garnacho <carlosg src gnome org>]

commit b2c8ff9c81b43968d83ea0891993270fda2a81ea
Author: Carlos Garnacho <carlosg gnome org>
Date:   Sat Aug 31 23:25:28 2019 +0200

    libtracker-sparql: Escape single quotes
    
    According to https://www.w3.org/TR/sparql11-query/#grammarEscapes,
    double and single quotes may be escaped regardless of the type of
    string literal we are dealing with.
    
    We should make tracker_sparql_escape_string() match accordingly.
    
    Related: https://gitlab.gnome.org/GNOME/nautilus/issues/163
             https://gitlab.gnome.org/GNOME/nautilus/merge_requests/456

 src/libtracker-sparql/tracker-utils.vala      | 5 ++++-
 tests/libtracker-sparql/tracker-sparql-test.c | 1 +
 2 files changed, 5 insertions(+), 1 deletion(-)
---
diff --git a/src/libtracker-sparql/tracker-utils.vala b/src/libtracker-sparql/tracker-utils.vala
index 32aac9a8f..a4664abf0 100644
--- a/src/libtracker-sparql/tracker-utils.vala
+++ b/src/libtracker-sparql/tracker-utils.vala
@@ -56,7 +56,7 @@ namespace Tracker.Sparql {
                char *p = (char*) literal;
 
                while (*p != '\0') {
-                       size_t len = Posix.strcspn ((string) p, "\t\n\r\b\f\"\\");
+                       size_t len = Posix.strcspn ((string) p, "\t\n\r\b\f\'\"\\");
                        str.append_len ((string) p, (long) len);
                        p += len;
 
@@ -76,6 +76,9 @@ namespace Tracker.Sparql {
                        case '\f':
                                str.append ("\\f");
                                break;
+                       case '\'':
+                               str.append ("\\'");
+                               break;
                        case '"':
                                str.append ("\\\"");
                                break;
diff --git a/tests/libtracker-sparql/tracker-sparql-test.c b/tests/libtracker-sparql/tracker-sparql-test.c
index de371feb5..3b60d18be 100644
--- a/tests/libtracker-sparql/tracker-sparql-test.c
+++ b/tests/libtracker-sparql/tracker-sparql-test.c
@@ -32,6 +32,7 @@ typedef struct {
 
 ESCAPE_TEST_DATA test_data []  = {
        { "SELECT \"a\"", "SELECT \\\"a\\\"" },
+       { "SELECT \'a\'", "SELECT \\\'a\\\'" },
        { "SELECT ?u \t \n \r \b \f", "SELECT ?u \\t \\n \\r \\b \\f" },
        { NULL, NULL }
 };