diff options
Diffstat (limited to 'src/couchdb/couch_key_tree.erl')
| -rw-r--r-- | src/couchdb/couch_key_tree.erl | 49 |
1 files changed, 36 insertions, 13 deletions
diff --git a/src/couchdb/couch_key_tree.erl b/src/couchdb/couch_key_tree.erl index bc723cc2..e5d3549f 100644 --- a/src/couchdb/couch_key_tree.erl +++ b/src/couchdb/couch_key_tree.erl @@ -16,6 +16,8 @@ -export([map/2, get_all_leafs/1, count_leafs/1, remove_leafs/2, get_all_leafs_full/1,stem/2,map_leafs/2]). +-include("couch_db.hrl"). + % Tree::term() is really a tree(), but we don't want to require R13B04 yet -type branch() :: {Key::term(), Value::term(), Tree::term()}. -type path() :: {Start::pos_integer(), branch()}. @@ -82,9 +84,9 @@ merge_at(OurTree, Place, [{Key, Value, SubTree}]) when Place < 0 -> no -> no end; -merge_at([{Key, Value, SubTree}|Sibs], 0, [{Key, _Value, InsertSubTree}]) -> +merge_at([{Key, V1, SubTree}|Sibs], 0, [{Key, V2, InsertSubTree}]) -> {Merged, Conflicts} = merge_simple(SubTree, InsertSubTree), - {ok, [{Key, Value, Merged} | Sibs], Conflicts}; + {ok, [{Key, value_pref(V1, V2), Merged} | Sibs], Conflicts}; merge_at([{OurKey, _, _} | _], 0, [{Key, _, _}]) when OurKey > Key -> % siblings keys are ordered, no point in continuing no; @@ -103,9 +105,10 @@ merge_simple([], B) -> {B, false}; merge_simple(A, []) -> {A, false}; -merge_simple([{Key, Value, SubA} | NextA], [{Key, _, SubB} | NextB]) -> +merge_simple([{Key, V1, SubA} | NextA], [{Key, V2, SubB} | NextB]) -> {MergedSubTree, Conflict1} = merge_simple(SubA, SubB), {MergedNextTree, Conflict2} = merge_simple(NextA, NextB), + Value = value_pref(V1, V2), {[{Key, Value, MergedSubTree} | MergedNextTree], Conflict1 or Conflict2}; merge_simple([{A, _, _} = Tree | Next], [{B, _, _} | _] = Insert) when A < B -> {Merged, _} = merge_simple(Next, Insert), @@ -157,14 +160,18 @@ remove_leafs(Trees, Keys) -> % filter out any that are in the keys list. {FilteredPaths, RemovedKeys} = filter_leafs(Paths, Keys, [], []), + SortedPaths = lists:sort( + [{Pos + 1 - length(Path), Path} || {Pos, Path} <- FilteredPaths] + ), + % convert paths back to trees NewTree = lists:foldl( - fun({PathPos, Path},TreeAcc) -> + fun({StartPos, Path},TreeAcc) -> [SingleTree] = lists:foldl( fun({K,V},NewTreeAcc) -> [{K,V,NewTreeAcc}] end, [], Path), - {NewTrees, _} = merge(TreeAcc, {PathPos + 1 - length(Path), SingleTree}), + {NewTrees, _} = merge(TreeAcc, {StartPos, SingleTree}), NewTrees - end, [], FilteredPaths), + end, [], SortedPaths), {NewTree, RemovedKeys}. @@ -314,19 +321,35 @@ map_leafs_simple(Fun, Pos, [{Key, Value, SubTree} | RestTree]) -> stem(Trees, Limit) -> - % flatten each branch in a tree into a tree path - Paths = get_all_leafs_full(Trees), - - Paths2 = [{Pos, lists:sublist(Path, Limit)} || {Pos, Path} <- Paths], + % flatten each branch in a tree into a tree path, sort by starting rev # + Paths = lists:sort(lists:map(fun({Pos, Path}) -> + StemmedPath = lists:sublist(Path, Limit), + {Pos + 1 - length(StemmedPath), StemmedPath} + end, get_all_leafs_full(Trees))), % convert paths back to trees lists:foldl( - fun({PathPos, Path},TreeAcc) -> + fun({StartPos, Path},TreeAcc) -> [SingleTree] = lists:foldl( fun({K,V},NewTreeAcc) -> [{K,V,NewTreeAcc}] end, [], Path), - {NewTrees, _} = merge(TreeAcc, {PathPos + 1 - length(Path), SingleTree}), + {NewTrees, _} = merge(TreeAcc, {StartPos, SingleTree}), NewTrees - end, [], Paths2). + end, [], Paths). + + +value_pref(Tuple, _) when is_tuple(Tuple), + (tuple_size(Tuple) == 3 orelse tuple_size(Tuple) == 4) -> + Tuple; +value_pref(_, Tuple) when is_tuple(Tuple), + (tuple_size(Tuple) == 3 orelse tuple_size(Tuple) == 4) -> + Tuple; +value_pref(?REV_MISSING, Other) -> + Other; +value_pref(Other, ?REV_MISSING) -> + Other; +value_pref(Last, _) -> + Last. + % Tests moved to test/etap/06?-*.t |