[tracker/wip/garnacho/sparql1.1: 63/69] libtracker-data: Add support for RAND() builtin function

[Carlos Garnacho <carlosg src gnome org>]

commit 7678fada2ce4c1c3596a4bc9a9edb598146ed686
Author: Carlos Garnacho <carlosg gnome org>
Date:   Wed Jul 29 00:03:14 2015 +0200

    libtracker-data: Add support for RAND() builtin function
    
    This function is defined in Sparql 1.1 query language recommendation,
    http://www.w3.org/TR/sparql11-query/#idp2130040

 src/libtracker-data/tracker-sparql-expression.vala |    6 ++++++
 src/libtracker-data/tracker-sparql-scanner.vala    |    6 ++++++
 2 files changed, 12 insertions(+), 0 deletions(-)
---
diff --git a/src/libtracker-data/tracker-sparql-expression.vala 
b/src/libtracker-data/tracker-sparql-expression.vala
index 59c4964..247a066 100644
--- a/src/libtracker-data/tracker-sparql-expression.vala
+++ b/src/libtracker-data/tracker-sparql-expression.vala
@@ -1343,6 +1343,12 @@ class Tracker.Sparql.Expression : Object {
                        type = translate_aggregate_expression (sql);
                        sql.append (")");
                        return type;
+               case SparqlTokenType.RAND:
+                       next ();
+                       expect (SparqlTokenType.OPEN_PARENS);
+                       expect (SparqlTokenType.CLOSE_PARENS);
+                       sql.append ("SparqlRand()");
+                       return PropertyType.DOUBLE;
                case SparqlTokenType.SECONDS:
                        next ();
                        expect (SparqlTokenType.OPEN_PARENS);
diff --git a/src/libtracker-data/tracker-sparql-scanner.vala b/src/libtracker-data/tracker-sparql-scanner.vala
index a27b99b..2fbbcf6 100644
--- a/src/libtracker-data/tracker-sparql-scanner.vala
+++ b/src/libtracker-data/tracker-sparql-scanner.vala
@@ -189,6 +189,10 @@ public class Tracker.SparqlScanner : Object {
                        case 'n':
                                if (matches (begin, "NULL")) return SparqlTokenType.NULL;
                                break;
+                       case 'R':
+                       case 'r':
+                               if (matches (begin, "RAND")) return SparqlTokenType.RAND;
+                               break;
                        case 'S':
                        case 's':
                                if (matches (begin, "SHA1")) return SparqlTokenType.SHA1;
@@ -1088,6 +1092,7 @@ public enum Tracker.SparqlTokenType {
        PLUS,
        PN_PREFIX,
        PREFIX,
+       RAND,
        REDUCED,
        REGEX,
        REPLACE,
@@ -1209,6 +1214,7 @@ public enum Tracker.SparqlTokenType {
                case PLUS: return "`+'";
                case PN_PREFIX: return "prefixed name";
                case PREFIX: return "`PREFIX'";
+               case RAND: return "`RAND'";
                case REDUCED: return "`REDUCED'";
                case REGEX: return "`REGEX'";
                case REPLACE: return "`REPLACE'";