db.(sqlite.)errors: add sql-index-exists error

basis/db/errors/errors.factor

@@ -43,6 +43,11 @@ TUPLE: sql-database-exists < sql-error message ;
 : <sql-database-exists> ( message -- error )
     f swap sql-database-exists boa ;
 
+TUPLE: sql-index-exists < sql-error name ;
+
+: <sql-index-exists> ( name -- error )
+    f swap sql-index-exists boa ;
+
 : ignore-error ( quot word -- )
     '[ dup @ [ drop ] [ rethrow ] if ] recover ; inline
 
@@ -60,3 +65,6 @@ TUPLE: sql-database-exists < sql-error message ;
 
 : ignore-database-exists ( quot -- )
     [ sql-database-exists? ] ignore-error ; inline
+
+: ignore-index-exists ( quot -- )
+    [ sql-index-exists? ] ignore-error ; inline

basis/db/sqlite/errors/errors-tests.factor

@@ -21,5 +21,13 @@ db.sqlite kernel locals tools.test ;
             { [ sql-table-exists? ] [ table>> "foo" = ] } 1&&
         ] must-fail-with
 
+        "create index main_index on foo(id);" sql-command
+
+        [
+            "create index main_index on foo(id);" sql-command
+        ] [
+            { [ sql-index-exists? ] [ name>> "main_index" = ] } 1&&
+        ] must-fail-with
+
     ] with-db
 ] with-test-file

basis/db/sqlite/errors/errors.factor

@@ -14,6 +14,8 @@ AlreadyExists = " already exists"
 SqliteError =
     "table " (!(AlreadyExists).)+:table AlreadyExists
       => [[ table >string <sql-table-exists> ]]
+    | "index " (!(AlreadyExists).)+:name AlreadyExists
+      => [[ name >string <sql-index-exists> ]]
     | "no such table: " .+:table
       => [[ table >string <sql-table-missing> ]]
     | .*:error