PgDatabaseMetaData.getIndexInfo() cast operands to smallint (#2242)

It is possible to break method PgDatabaseMetaData.getIndexInfo() by adding certain custom operators.
This PR casts operands in a query so that PgDatabaseMetaData.getIndexInfo() works in presence
of such operator config.

Creating this operator triggers this issue:

CREATE OR REPLACE FUNCTION f6(numeric, integer) returns integer as 'BEGIN return $1::integer & $2;END;' language plpgsql immutable;
CREATE OPERATOR & (LEFTARG = numeric, RIGHTARG = integer, PROCEDURE = f6);

Fixes #2241

pgjdbc/src/main/java/org/postgresql/jdbc/PgDatabaseMetaData.java

@@ -2526,14 +2526,14 @@ public ResultSet getIndexInfo(
                 + "    trim(both '\"' from pg_catalog.pg_get_indexdef(tmp.CI_OID, tmp.ORDINAL_POSITION, false)) AS COLUMN_NAME, "
                 + (connection.haveMinimumServerVersion(ServerVersion.v9_6)
                         ? "  CASE tmp.AM_NAME "
-                        + "    WHEN 'btree' THEN CASE tmp.I_INDOPTION[tmp.ORDINAL_POSITION - 1] & 1 "
+                        + "    WHEN 'btree' THEN CASE tmp.I_INDOPTION[tmp.ORDINAL_POSITION - 1] & 1::smallint "
                         + "      WHEN 1 THEN 'D' "
                         + "      ELSE 'A' "
                         + "    END "
                         + "    ELSE NULL "
                         + "  END AS ASC_OR_DESC, "
                         : "  CASE tmp.AM_CANORDER "
-                        + "    WHEN true THEN CASE tmp.I_INDOPTION[tmp.ORDINAL_POSITION - 1] & 1 "
+                        + "    WHEN true THEN CASE tmp.I_INDOPTION[tmp.ORDINAL_POSITION - 1] & 1::smallint "
                         + "      WHEN 1 THEN 'D' "
                         + "      ELSE 'A' "
                         + "    END "

pgjdbc/src/test/java/org/postgresql/test/jdbc2/DatabaseMetaDataTest.java

@@ -120,6 +120,12 @@ public void setUp() throws Exception {
           "CREATE OR REPLACE FUNCTION f5() RETURNS TABLE (i int) LANGUAGE sql AS 'SELECT 1'");
     }
 
+    // create a custom `&` operator, which caused failure with `&` usage in getIndexInfo()
+    stmt.execute(
+        "CREATE OR REPLACE FUNCTION f6(numeric, integer) returns integer as 'BEGIN return $1::integer & $2;END;' language plpgsql immutable;");
+    stmt.execute("DROP OPERATOR IF EXISTS & (numeric, integer)");
+    stmt.execute("CREATE OPERATOR & (LEFTARG = numeric, RIGHTARG = integer, PROCEDURE = f6)");
+
     TestUtil.createDomain(con, "nndom", "int not null");
     TestUtil.createDomain(con, "varbit2", "varbit(3)");
     TestUtil.createDomain(con, "float83", "numeric(8,3)");
@@ -154,6 +160,8 @@ public void tearDown() throws Exception {
     stmt.execute("DROP FUNCTION f1(int, varchar)");
     stmt.execute("DROP FUNCTION f2(int, varchar)");
     stmt.execute("DROP FUNCTION f3(int, varchar)");
+    stmt.execute("DROP OPERATOR IF EXISTS & (numeric, integer)");
+    stmt.execute("DROP FUNCTION f6(numeric, integer)");
     TestUtil.dropTable(con, "domaintable");
     TestUtil.dropDomain(con, "nndom");
     TestUtil.dropDomain(con, "varbit2");