[sql] Import SQLite 3.17.0.

third_party/sqlite/src/test/wal6.test

 # 2010 December 1
 #
 # The author disclaims copyright to this source code.  In place of
 # a legal notice, here is a blessing:
 #
 #    May you do good and not evil.
 #    May you find forgiveness for yourself and forgive others.
 #    May you share freely, never taking more than you give.
 #
 #***********************************************************************
@@ skipping 216 matching lines @@
   sqlite3 db2 test.db
 } {}
 
 do_test 4.4.1 { 
   catchsql { SELECT * FROM t1 } db2 
 } {0 {1 2}}
 do_test 4.4.2 { 
   catchsql { SELECT * FROM t2 } db2 
 } {1 {database disk image is malformed}}
 
+#-------------------------------------------------------------------------
+# Confirm that it is possible to get an SQLITE_BUSY_SNAPSHOT error from
+# "BEGIN EXCLUSIVE" if the connection already has an open read-transaction.
+#
+db close
+db2 close
+reset_db
+sqlite3 db2 test.db
+do_execsql_test 5.1 {
+  PRAGMA journal_mode = wal;
+  CREATE TABLE t1(x, y);
+  INSERT INTO t1 VALUES(1, 2);
+  INSERT INTO t1 VALUES(3, 4);
+} {wal}
+do_test 5.2 {
+  set res [list]
+  db eval {
+    SELECT * FROM t1
+  } {
+    if {$x==1} {
+      db2 eval { INSERT INTO t1 VALUES(5, 6) }
+    } 
+    if {$x==3} {
+      set res [catchsql {BEGIN EXCLUSIVE}]
+      lappend res [sqlite3_extended_errcode db]
+    } 
+  }
+  set res
+} {1 {database is locked} SQLITE_BUSY_SNAPSHOT}
+
+
 
 finish_test
-