code improvements from tidier. Patch by Kostis Sagonas. COUCHDB-570

git-svn-id: https://svn.apache.org/repos/asf/couchdb/trunk@882903 13f79535-47bb-0310-9956-ffa450edef68

25 files changed, 127 insertions, 158 deletions

diff --git a/src/couchdb/couch_btree.erl b/src/couchdb/couch_btree.erl
index 0dad13f8..73d50805 100644
--- a/src/couchdb/couch_btree.erl
+++ b/src/couchdb/couch_btree.erl
@@ -217,16 +217,12 @@ lookup(Bt, {Pointer, _Reds}, Keys) ->
         lookup_kvnode(Bt, list_to_tuple(NodeList), 1, Keys, [])
     end.
 
-
-
 lookup_kpnode(_Bt, _NodeTuple, _LowerBound, [], Output) ->
     {ok, lists:reverse(Output)};
-
-lookup_kpnode(_Bt, NodeTuple, LowerBound, Keys, Output) when size(NodeTuple) < LowerBound ->
+lookup_kpnode(_Bt, NodeTuple, LowerBound, Keys, Output) when tuple_size(NodeTuple) < LowerBound ->
     {ok, lists:reverse(Output, [{Key, not_found} || Key <- Keys])};
-
 lookup_kpnode(Bt, NodeTuple, LowerBound, [FirstLookupKey | _] = LookupKeys, Output) ->
-    N = find_first_gteq(Bt, NodeTuple, LowerBound, size(NodeTuple), FirstLookupKey),
+    N = find_first_gteq(Bt, NodeTuple, LowerBound, tuple_size(NodeTuple), FirstLookupKey),
     {Key, PointerInfo} = element(N, NodeTuple),
     SplitFun = fun(LookupKey) -> not less(Bt, Key, LookupKey) end,
     case lists:splitwith(SplitFun, LookupKeys) of
@@ -240,11 +236,11 @@ lookup_kpnode(Bt, NodeTuple, LowerBound, [FirstLookupKey | _] = LookupKeys, Outp
 
 lookup_kvnode(_Bt, _NodeTuple, _LowerBound, [], Output) ->
     {ok, lists:reverse(Output)};
-lookup_kvnode(_Bt, NodeTuple, LowerBound, Keys, Output) when size(NodeTuple) < LowerBound ->
+lookup_kvnode(_Bt, NodeTuple, LowerBound, Keys, Output) when tuple_size(NodeTuple) < LowerBound ->
     % keys not found
     {ok, lists:reverse(Output, [{Key, not_found} || Key <- Keys])};
 lookup_kvnode(Bt, NodeTuple, LowerBound, [LookupKey | RestLookupKeys], Output) ->
-    N = find_first_gteq(Bt, NodeTuple, LowerBound, size(NodeTuple), LookupKey),
+    N = find_first_gteq(Bt, NodeTuple, LowerBound, tuple_size(NodeTuple), LookupKey),
     {Key, Value} = element(N, NodeTuple),
     case less(Bt, LookupKey, Key) of
     true ->
@@ -272,14 +268,14 @@ complete_root(Bt, KPs) ->
 
 %%%%%%%%%%%%% The chunkify function sucks! %%%%%%%%%%%%%
 % It is inaccurate as it does not account for compression when blocks are
-% written. Plus with the "case size(term_to_binary(InList)) of" code it's
-% probably really inefficient.
+% written. Plus with the "case byte_size(term_to_binary(InList)) of" code
+% it's probably really inefficient.
 
 % dialyzer says this pattern is never matched
 % chunkify(_Bt, []) ->
 %     [];
 chunkify(Bt, InList) ->
-    case size(term_to_binary(InList)) of
+    case byte_size(term_to_binary(InList)) of
     Size when Size > ?CHUNK_THRESHOLD ->
         NumberOfChunksLikely = ((Size div ?CHUNK_THRESHOLD) + 1),
         ChunkThreshold = Size div NumberOfChunksLikely,
@@ -293,7 +289,7 @@ chunkify(_Bt, [], _ChunkThreshold, [], 0, OutputChunks) ->
 chunkify(_Bt, [], _ChunkThreshold, OutList, _OutListSize, OutputChunks) ->
     lists:reverse([lists:reverse(OutList) | OutputChunks]);
 chunkify(Bt, [InElement | RestInList], ChunkThreshold, OutList, OutListSize, OutputChunks) ->
-    case size(term_to_binary(InElement)) of
+    case byte_size(term_to_binary(InElement)) of
     Size when (Size + OutListSize) > ChunkThreshold andalso OutList /= [] ->
         chunkify(Bt, RestInList, ChunkThreshold, [], 0, [lists:reverse([InElement | OutList]) | OutputChunks]);
     Size ->
@@ -319,7 +315,7 @@ modify_node(Bt, RootPointerInfo, Actions, QueryOutput) ->
     [] ->  % no nodes remain
         {ok, [], QueryOutput2, Bt2};
     NodeList ->  % nothing changed
-        {LastKey, _LastValue} = element(size(NodeTuple), NodeTuple),
+        {LastKey, _LastValue} = element(tuple_size(NodeTuple), NodeTuple),
         {ok, [{LastKey, RootPointerInfo}], QueryOutput2, Bt2};
     _Else2 ->
         {ok, ResultList, Bt3} = write_node(Bt2, NodeType, NewNodeList),
@@ -357,18 +353,19 @@ modify_kpnode(Bt, {}, _LowerBound, Actions, [], QueryOutput) ->
     modify_node(Bt, nil, Actions, QueryOutput);
 modify_kpnode(Bt, NodeTuple, LowerBound, [], ResultNode, QueryOutput) ->
     {ok, lists:reverse(ResultNode, bounded_tuple_to_list(NodeTuple, LowerBound,
-            size(NodeTuple),  [])), QueryOutput, Bt};
+            tuple_size(NodeTuple), [])), QueryOutput, Bt};
 modify_kpnode(Bt, NodeTuple, LowerBound,
         [{_, FirstActionKey, _}|_]=Actions, ResultNode, QueryOutput) ->
-    N = find_first_gteq(Bt, NodeTuple, LowerBound, size(NodeTuple), FirstActionKey),
-    case N == size(NodeTuple) of
+    Sz = tuple_size(NodeTuple),
+    N = find_first_gteq(Bt, NodeTuple, LowerBound, Sz, FirstActionKey),
+    case N =:= Sz of
     true  ->
         % perform remaining actions on last node
-        {_, PointerInfo} = element(size(NodeTuple), NodeTuple),
+        {_, PointerInfo} = element(Sz, NodeTuple),
         {ok, ChildKPs, QueryOutput2, Bt2} =
             modify_node(Bt, PointerInfo, Actions, QueryOutput),
         NodeList = lists:reverse(ResultNode, bounded_tuple_to_list(NodeTuple, LowerBound,
-            size(NodeTuple) - 1, ChildKPs)),
+            Sz - 1, ChildKPs)),
         {ok, NodeList, QueryOutput2, Bt2};
     false ->
         {NodeKey, PointerInfo} = element(N, NodeTuple),
@@ -409,8 +406,8 @@ find_first_gteq(Bt, Tuple, Start, End, Key) ->
     end.
 
 modify_kvnode(Bt, NodeTuple, LowerBound, [], ResultNode, QueryOutput) ->
-    {ok, lists:reverse(ResultNode, bounded_tuple_to_list(NodeTuple, LowerBound, size(NodeTuple), [])), QueryOutput, Bt};
-modify_kvnode(Bt, NodeTuple, LowerBound, [{ActionType, ActionKey, ActionValue} | RestActions], ResultNode, QueryOutput) when LowerBound > size(NodeTuple) ->
+    {ok, lists:reverse(ResultNode, bounded_tuple_to_list(NodeTuple, LowerBound, tuple_size(NodeTuple), [])), QueryOutput, Bt};
+modify_kvnode(Bt, NodeTuple, LowerBound, [{ActionType, ActionKey, ActionValue} | RestActions], ResultNode, QueryOutput) when LowerBound > tuple_size(NodeTuple) ->
     case ActionType of
     insert ->
         modify_kvnode(Bt, NodeTuple, LowerBound, RestActions, [{ActionKey, ActionValue} | ResultNode], QueryOutput);
@@ -422,7 +419,7 @@ modify_kvnode(Bt, NodeTuple, LowerBound, [{ActionType, ActionKey, ActionValue} |
         modify_kvnode(Bt, NodeTuple, LowerBound, RestActions, ResultNode, [{not_found, {ActionKey, nil}} | QueryOutput])
     end;
 modify_kvnode(Bt, NodeTuple, LowerBound, [{ActionType, ActionKey, ActionValue} | RestActions], AccNode, QueryOutput) ->
-    N = find_first_gteq(Bt, NodeTuple, LowerBound, size(NodeTuple), ActionKey),
+    N = find_first_gteq(Bt, NodeTuple, LowerBound, tuple_size(NodeTuple), ActionKey),
     {Key, Value} = element(N, NodeTuple),
     ResultNode =  bounded_tuple_to_revlist(NodeTuple, LowerBound, N - 1, AccNode),
     case less(Bt, ActionKey, Key) of
diff --git a/src/couchdb/couch_db.erl b/src/couchdb/couch_db.erl
index 7630989a..a729f215 100644
--- a/src/couchdb/couch_db.erl
+++ b/src/couchdb/couch_db.erl
@@ -290,7 +290,7 @@ validate_doc_update(#db{user_ctx=UserCtx, admins=Admins},
         #doc{id= <<"_design/",_/binary>>}, _GetDiskDocFun) ->
     UserNames = [UserCtx#user_ctx.name | UserCtx#user_ctx.roles],
     % if the user is a server admin or db admin, allow the save
-    case length(UserNames -- [<<"_admin">> | Admins]) == length(UserNames) of
+    case length(UserNames -- [<<"_admin">> | Admins]) =:= length(UserNames) of
     true ->
         % not an admin
         {unauthorized, <<"You are not a server or database admin.">>};
@@ -478,8 +478,8 @@ prep_and_validate_replicated_updates(Db, [Bucket|RestBuckets], [OldInfo|RestOldI
 
 new_revid(#doc{body=Body,revs={OldStart,OldRevs},
         atts=Atts,deleted=Deleted}) ->
-    case [{N, T, M} || #att{name=N,type=T,md5=M} <- Atts, M /= <<>>] of
-    Atts2 when length(Atts) /= length(Atts2) ->
+    case [{N, T, M} || #att{name=N,type=T,md5=M} <- Atts, M =/= <<>>] of
+    Atts2 when length(Atts) =/= length(Atts2) ->
         % We must have old style non-md5 attachments
         ?l2b(integer_to_list(couch_util:rand32()));
     Atts2 ->
@@ -503,7 +503,7 @@ check_dup_atts(#doc{atts=Atts}=Doc) ->
     check_dup_atts2(Atts2),
     Doc.
 
-check_dup_atts2([#att{name=N1}, #att{name=N2} | _]) when N1 == N2 ->
+check_dup_atts2([#att{name=N}, #att{name=N} | _]) ->
     throw({bad_request, <<"Duplicate attachments">>});
 check_dup_atts2([_ | Rest]) ->
     check_dup_atts2(Rest);
@@ -803,10 +803,10 @@ handle_call(is_idle, _From, #db{fd_ref_counter=RefCntr, compactor_pid=Compact,
             waiting_delayed_commit=Delay}=Db) ->
     % Idle means no referrers. Unless in the middle of a compaction file switch,
     % there are always at least 2 referrers, couch_db_updater and us.
-    {reply, (Delay == nil) and (Compact == nil) and (couch_ref_counter:count(RefCntr) == 2), Db};
+    {reply, (Delay == nil) andalso (Compact == nil) andalso (couch_ref_counter:count(RefCntr) == 2), Db};
 handle_call({db_updated, NewDb}, _From, #db{fd_ref_counter=OldRefCntr}) ->
     #db{fd_ref_counter=NewRefCntr}=NewDb,
-    case NewRefCntr == OldRefCntr of
+    case NewRefCntr =:= OldRefCntr of
     true -> ok;
     false ->
         couch_ref_counter:add(NewRefCntr),
diff --git a/src/couchdb/couch_db_updater.erl b/src/couchdb/couch_db_updater.erl
index 31366a84..d9951cf6 100644
--- a/src/couchdb/couch_db_updater.erl
+++ b/src/couchdb/couch_db_updater.erl
@@ -318,11 +318,12 @@ btree_by_seq_reduce(reduce, DocInfos) ->
 btree_by_seq_reduce(rereduce, Reds) ->
     lists:sum(Reds).
 
-simple_upgrade_record(Old, New) when size(Old) == size(New)->
+simple_upgrade_record(Old, New) when tuple_size(Old) =:= tuple_size(New) ->
     Old;
 simple_upgrade_record(Old, New) ->
+    OldSz = tuple_size(Old),
     NewValuesTail =
-        lists:sublist(tuple_to_list(New), size(Old) + 1, size(New)-size(Old)),
+        lists:sublist(tuple_to_list(New), OldSz + 1, tuple_size(New) - OldSz),
     list_to_tuple(tuple_to_list(Old) ++ NewValuesTail).
 
 
@@ -751,9 +752,9 @@ copy_compact(Db, NewDb0, Retry) ->
     fun(#doc_info{high_seq=Seq}=DocInfo, _Offset, {AccNewDb, AccUncopied, TotalCopied}) ->
         couch_task_status:update("Copied ~p of ~p changes (~p%)",
                 [TotalCopied, TotalChanges, (TotalCopied*100) div TotalChanges]),
-        if TotalCopied rem 1000 == 0 ->
+        if TotalCopied rem 1000 =:= 0 ->
             NewDb2 = copy_docs(Db, AccNewDb, lists:reverse([DocInfo | AccUncopied]), Retry),
-            if TotalCopied rem 10000 == 0 ->
+            if TotalCopied rem 10000 =:= 0 ->
                 {ok, {commit_data(NewDb2#db{update_seq=Seq}), [], TotalCopied + 1}};
             true ->
                 {ok, {NewDb2#db{update_seq=Seq}, [], TotalCopied + 1}}
diff --git a/src/couchdb/couch_doc.erl b/src/couchdb/couch_doc.erl
index eb07a9e6..d0c2918a 100644
--- a/src/couchdb/couch_doc.erl
+++ b/src/couchdb/couch_doc.erl
@@ -40,7 +40,7 @@ to_json_revisions(Options, Start, RevIds) ->
                 {<<"ids">>, [revid_to_str(R) ||R <- RevIds]}]}}]
     end.
 
-revid_to_str(RevId) when size(RevId) == 16 ->
+revid_to_str(RevId) when size(RevId) =:= 16 ->
     ?l2b(couch_util:to_hex(RevId));
 revid_to_str(RevId) ->
     RevId.
@@ -122,10 +122,10 @@ from_json_obj({Props}) ->
 from_json_obj(_Other) ->
     throw({bad_request, "Document must be a JSON object"}).
 
-parse_revid(RevId) when size(RevId) == 32 ->
+parse_revid(RevId) when size(RevId) =:= 32 ->
     RevInt = erlang:list_to_integer(?b2l(RevId), 16),
      <<RevInt:128>>;
-parse_revid(RevId) when length(RevId) == 32 ->
+parse_revid(RevId) when length(RevId) =:= 32 ->
     RevInt = erlang:list_to_integer(RevId, 16),
      <<RevInt:128>>;
 parse_revid(RevId) when is_binary(RevId) ->
@@ -222,7 +222,7 @@ transfer_fields([{<<"_revisions">>, {Props}} | Rest], Doc) ->
     RevIds2 = [parse_revid(RevId) || RevId <- RevIds],
     transfer_fields(Rest, Doc#doc{revs={Start, RevIds2}});
 
-transfer_fields([{<<"_deleted">>, B} | Rest], Doc) when (B==true) or (B==false) ->
+transfer_fields([{<<"_deleted">>, B} | Rest], Doc) when is_boolean(B) ->
     transfer_fields(Rest, Doc#doc{deleted=B});
 
 % ignored fields
diff --git a/src/couchdb/couch_file.erl b/src/couchdb/couch_file.erl
index 2dfc5403..5904260c 100644
--- a/src/couchdb/couch_file.erl
+++ b/src/couchdb/couch_file.erl
@@ -402,14 +402,14 @@ extract_header(Prefix, Bin) ->
 write_old_header(Fd, Prefix, Data) ->
     TermBin = term_to_binary(Data),
     % the size of all the bytes written to the header, including the md5 signature (16 bytes)
-    FilledSize = size(Prefix) + size(TermBin) + 16,
+    FilledSize = byte_size(Prefix) + byte_size(TermBin) + 16,
     {TermBin2, FilledSize2} =
     case FilledSize > ?HEADER_SIZE of
     true ->
         % too big!
         {ok, Pos} = append_binary(Fd, TermBin),
         PtrBin = term_to_binary({pointer_to_header_data, Pos}),
-        {PtrBin, size(Prefix) + size(PtrBin) + 16};
+        {PtrBin, byte_size(Prefix) + byte_size(PtrBin) + 16};
     false ->
         {TermBin, FilledSize}
     end,
@@ -465,7 +465,7 @@ calculate_total_read_len(BlockOffset, FinalLen) ->
         FinalLen;
     BlockLeft ->
         FinalLen + ((FinalLen - BlockLeft) div (?SIZE_BLOCK -1)) +
-            if ((FinalLen - BlockLeft) rem (?SIZE_BLOCK -1)) == 0 -> 0;
+            if ((FinalLen - BlockLeft) rem (?SIZE_BLOCK -1)) =:= 0 -> 0;
                 true -> 1 end
     end.
 
@@ -499,8 +499,8 @@ split_iolist(List, 0, BeginAcc) ->
     {lists:reverse(BeginAcc), List};
 split_iolist([], SplitAt, _BeginAcc) ->
     SplitAt;
-split_iolist([<<Bin/binary>> | Rest], SplitAt, BeginAcc)  when SplitAt > size(Bin) ->
-    split_iolist(Rest, SplitAt - size(Bin), [Bin | BeginAcc]);
+split_iolist([<<Bin/binary>> | Rest], SplitAt, BeginAcc) when SplitAt > byte_size(Bin) ->
+    split_iolist(Rest, SplitAt - byte_size(Bin), [Bin | BeginAcc]);
 split_iolist([<<Bin/binary>> | Rest], SplitAt, BeginAcc) ->
     <<Begin:SplitAt/binary,End/binary>> = Bin,
     split_iolist([End | Rest], 0, [Begin | BeginAcc]);
diff --git a/src/couchdb/couch_httpd.erl b/src/couchdb/couch_httpd.erl
index caffdd51..a3e486f1 100644
--- a/src/couchdb/couch_httpd.erl
+++ b/src/couchdb/couch_httpd.erl
@@ -97,17 +97,17 @@ start_link() ->
 make_arity_1_fun(SpecStr) ->
     case couch_util:parse_term(SpecStr) of
     {ok, {Mod, Fun, SpecArg}} ->
-        fun(Arg) -> apply(Mod, Fun, [Arg, SpecArg]) end;
+        fun(Arg) -> Mod:Fun(Arg, SpecArg) end;
     {ok, {Mod, Fun}} ->
-        fun(Arg) -> apply(Mod, Fun, [Arg]) end
+        fun(Arg) -> Mod:Fun(Arg) end
     end.
 
 make_arity_2_fun(SpecStr) ->
     case couch_util:parse_term(SpecStr) of
     {ok, {Mod, Fun, SpecArg}} ->
-        fun(Arg1, Arg2) -> apply(Mod, Fun, [Arg1, Arg2, SpecArg]) end;
+        fun(Arg1, Arg2) -> Mod:Fun(Arg1, Arg2, SpecArg) end;
     {ok, {Mod, Fun}} ->
-        fun(Arg1, Arg2) -> apply(Mod, Fun, [Arg1, Arg2]) end
+        fun(Arg1, Arg2) -> Mod:Fun(Arg1, Arg2) end
     end.
 
 % SpecStr is "{my_module, my_fun}, {my_module2, my_fun2}"
diff --git a/src/couchdb/couch_httpd_auth.erl b/src/couchdb/couch_httpd_auth.erl
index fb76c72a..b244e16e 100644
--- a/src/couchdb/couch_httpd_auth.erl
+++ b/src/couchdb/couch_httpd_auth.erl
@@ -377,7 +377,7 @@ create_user_req(#httpd{method='POST', mochi_req=MochiReq}=Req, Db) ->
         ?LOG_DEBUG("Can't create ~s: already exists", [?b2l(UserName)]),
          throw({forbidden, <<"User already exists.">>})
     end.
-    
+
 update_user_req(#httpd{method='PUT', mochi_req=MochiReq, user_ctx=UserCtx}=Req, Db, UserName) ->
     Name = UserCtx#user_ctx.name,
     UserRoles = UserCtx#user_ctx.roles,
@@ -413,16 +413,14 @@ update_user_req(#httpd{method='PUT', mochi_req=MochiReq, user_ctx=UserCtx}=Req,
         
         PasswordHash = case lists:member(<<"_admin">>, UserRoles) of
         true ->
-            Hash = case Password of
+            case Password of
                 <<>> -> CurrentPasswordHash;
                 _Else ->
-                    H = hash_password(Password, UserSalt),
-                    H
-                end,
-            Hash;
-        false when Name == UserName ->
+                    hash_password(Password, UserSalt)
+	    end;
+        false when Name =:= UserName ->
             %% for user we test old password before allowing change
-            Hash = case Password of
+            case Password of
                 <<>> -> 
                     CurrentPasswordHash;
                 _P when OldPassword =:= [] ->
@@ -430,16 +428,13 @@ update_user_req(#httpd{method='PUT', mochi_req=MochiReq, user_ctx=UserCtx}=Req,
                 _Else ->
                     OldPasswordHash = hash_password(OldPassword1, UserSalt),
                     ?LOG_DEBUG("~p == ~p", [CurrentPasswordHash, OldPasswordHash]),
-                    Hash1 = case CurrentPasswordHash of
-                        ExpectedHash when ExpectedHash == OldPasswordHash ->
-                            H = hash_password(Password, UserSalt),
-                            H;
+                    case CurrentPasswordHash of
+                        ExpectedHash when ExpectedHash =:= OldPasswordHash ->
+                            hash_password(Password, UserSalt);
                         _ ->
                             throw({forbidden, <<"Old password is incorrect.">>})
-                        end,
-                    Hash1
-                end,
-            Hash;
+		    end
+                end;
         _ ->
             throw({forbidden, <<"You aren't allowed to change this password.">>})
         end, 
@@ -457,24 +452,24 @@ update_user_req(#httpd{method='PUT', mochi_req=MochiReq, user_ctx=UserCtx}=Req,
 handle_user_req(#httpd{method='POST'}=Req) ->
     DbName = couch_config:get("couch_httpd_auth", "authentication_db"),
     ensure_users_db_exists(?l2b(DbName)),
-    case couch_db:open(?l2b(DbName), [{user_ctx, #user_ctx{roles=[<<"_admin">>]}}]) of
-        {ok, Db} -> create_user_req(Req, Db)
-    end;
+    {ok, Db} = couch_db:open(?l2b(DbName),
+			     [{user_ctx, #user_ctx{roles=[<<"_admin">>]}}]),
+    create_user_req(Req, Db);
 handle_user_req(#httpd{method='PUT', path_parts=[_]}=_Req) ->
     throw({bad_request, <<"Username is missing">>});
 handle_user_req(#httpd{method='PUT', path_parts=[_, UserName]}=Req) ->
     DbName = couch_config:get("couch_httpd_auth", "authentication_db"),
     ensure_users_db_exists(?l2b(DbName)),
-    case couch_db:open(?l2b(DbName), [{user_ctx, #user_ctx{roles=[<<"_admin">>]}}]) of
-        {ok, Db} -> update_user_req(Req, Db, UserName)
-    end;
+    {ok, Db} = couch_db:open(?l2b(DbName),
+			     [{user_ctx, #user_ctx{roles=[<<"_admin">>]}}]),
+    update_user_req(Req, Db, UserName);
 handle_user_req(Req) ->
-     send_method_not_allowed(Req, "POST,PUT").
+    couch_httpd:send_method_not_allowed(Req, "POST,PUT").
 
 to_int(Value) when is_binary(Value) ->
     to_int(?b2l(Value)); 
 to_int(Value) when is_list(Value) ->
-    erlang:list_to_integer(Value);
+    list_to_integer(Value);
 to_int(Value) when is_integer(Value) ->
     Value.
 
diff --git a/src/couchdb/couch_httpd_db.erl b/src/couchdb/couch_httpd_db.erl
index 71fc3f48..5d23232e 100644
--- a/src/couchdb/couch_httpd_db.erl
+++ b/src/couchdb/couch_httpd_db.erl
@@ -1021,7 +1021,7 @@ db_attachment_req(#httpd{method=Method}=Req, Db, DocId, FileNameParts)
             [];
         _ ->
             [#att{
-                name=FileName,
+                name = FileName,
                 type = case couch_httpd:header_value(Req,"Content-Type") of
                     undefined ->
                         % We could throw an error here or guess by the FileName.
diff --git a/src/couchdb/couch_httpd_external.erl b/src/couchdb/couch_httpd_external.erl
index 0a26bcf7..86b2bfc6 100644
--- a/src/couchdb/couch_httpd_external.erl
+++ b/src/couchdb/couch_httpd_external.erl
@@ -86,6 +86,7 @@ json_req_obj(#httpd{mochi_req=Req,
 
 to_json_terms(Data) ->
     to_json_terms(Data, []).
+
 to_json_terms([], Acc) ->
     {lists:reverse(Acc)};
 to_json_terms([{Key, Value} | Rest], Acc) when is_atom(Key) ->
@@ -93,7 +94,6 @@ to_json_terms([{Key, Value} | Rest], Acc) when is_atom(Key) ->
 to_json_terms([{Key, Value} | Rest], Acc) ->
     to_json_terms(Rest, [{list_to_binary(Key), list_to_binary(Value)} | Acc]).
 
-
 send_external_response(#httpd{mochi_req=MochiReq}=Req, Response) ->
     #extern_resp_args{
         code = Code,
diff --git a/src/couchdb/couch_httpd_show.erl b/src/couchdb/couch_httpd_show.erl
index 4ed11c2a..14b9b415 100644
--- a/src/couchdb/couch_httpd_show.erl
+++ b/src/couchdb/couch_httpd_show.erl
@@ -50,11 +50,10 @@ handle_doc_update_req(#httpd{
     #doc{body={Props}} = couch_httpd_db:couch_doc_open(Db, DesignId, nil, []),
     Lang = proplists:get_value(<<"language">>, Props, <<"javascript">>),
     UpdateSrc = couch_util:get_nested_json_value({Props}, [<<"updates">>, UpdateName]),
-    Doc = try couch_httpd_db:couch_doc_open(Db, DocId, nil, [conflicts]) of
-        FoundDoc -> FoundDoc
-    catch
-        _ -> nil
-    end,
+    Doc = try couch_httpd_db:couch_doc_open(Db, DocId, nil, [conflicts])
+	  catch
+	      _ -> nil
+	  end,
     send_doc_update_response(Lang, UpdateSrc, DocId, Doc, Req, Db);
 
 handle_doc_update_req(#httpd{
@@ -66,13 +65,11 @@ handle_doc_update_req(#httpd{
     UpdateSrc = couch_util:get_nested_json_value({Props}, [<<"updates">>, UpdateName]),
     send_doc_update_response(Lang, UpdateSrc, nil, nil, Req, Db);
 
-
 handle_doc_update_req(Req, _Db) ->
     send_error(Req, 404, <<"update_error">>, <<"Invalid path.">>).
 
 
 
-
 handle_doc_show(Req, DesignName, ShowName, DocId, Db) ->
     DesignId = <<"_design/", DesignName/binary>>,
     #doc{body={Props}} = couch_httpd_db:couch_doc_open(Db, DesignId, nil, []),
@@ -81,8 +78,7 @@ handle_doc_show(Req, DesignName, ShowName, DocId, Db) ->
     Doc = case DocId of
         nil -> nil;
         _ ->
-        try couch_httpd_db:couch_doc_open(Db, DocId, nil, [conflicts]) of
-            FoundDoc -> FoundDoc
+        try couch_httpd_db:couch_doc_open(Db, DocId, nil, [conflicts])
         catch
             _ -> nil
         end
diff --git a/src/couchdb/couch_httpd_view.erl b/src/couchdb/couch_httpd_view.erl
index 4c9902ed..cb9f8687 100644
--- a/src/couchdb/couch_httpd_view.erl
+++ b/src/couchdb/couch_httpd_view.erl
@@ -236,10 +236,7 @@ parse_view_params(Req, Keys, ViewType) ->
     lists:foldl(fun({K, V}, Acc) ->
             parse_view_param(K, V) ++ Acc
         end, [], QueryList),
-    IsMultiGet = case Keys of
-        nil -> false;
-        _ -> true
-    end,
+    IsMultiGet = (Keys =/= nil),
     Args = #view_query_args{
         view_type=ViewType,
         multi_get=IsMultiGet
diff --git a/src/couchdb/couch_key_tree.erl b/src/couchdb/couch_key_tree.erl
index 830820f3..d5944119 100644
--- a/src/couchdb/couch_key_tree.erl
+++ b/src/couchdb/couch_key_tree.erl
@@ -34,7 +34,7 @@ merge(A, B) ->
         end,
         {A, false}, B),
     if HasConflicts or
-            ((length(Merged) /= length(A)) and (length(Merged) /= length(B))) ->
+            ((length(Merged) =/= length(A)) and (length(Merged) =/= length(B))) ->
         Conflicts = conflicts;
     true ->
         Conflicts = no_conflicts
@@ -221,7 +221,7 @@ get_full_key_paths(_Pos, [], KeysToGet, _KeyPathAcc) ->
 get_full_key_paths(Pos, [{KeyId, Value, SubTree} | RestTree], KeysToGet, KeyPathAcc) ->
     KeysToGet2 = KeysToGet -- [{Pos, KeyId}],
     CurrentNodeResult =
-    case length(KeysToGet2) == length(KeysToGet) of
+    case length(KeysToGet2) =:= length(KeysToGet) of
     true -> % not in the key list.
         [];
     false -> % this node is the key list. return it
diff --git a/src/couchdb/couch_native_process.erl b/src/couchdb/couch_native_process.erl
index 65b733bf..2b74073c 100644
--- a/src/couchdb/couch_native_process.erl
+++ b/src/couchdb/couch_native_process.erl
@@ -120,19 +120,14 @@ run(State, [<<"validate">>, BFun, NDoc, ODoc, Ctx]) ->
     {State, catch Fun(NDoc, ODoc, Ctx)};
 run(State, [<<"filter">>, Docs, Req]) ->
     {_Sig, Fun} = hd(State#evstate.funs),
-    Resp = lists:map(fun(Doc) ->
-        case (catch Fun(Doc, Req)) of
-            true -> true;
-            _ -> false
-        end
-    end, Docs),
+    Resp = lists:map(fun(Doc) -> (catch Fun(Doc, Req)) =:= true end, Docs),
     {State, [true, Resp]};
 run(State, [<<"show">>, BFun, Doc, Req]) ->
     {_Sig, Fun} = makefun(State, BFun),
     Resp = case (catch Fun(Doc, Req)) of
         FunResp when is_list(FunResp) ->
             FunResp;
-        FunResp when is_tuple(FunResp), size(FunResp) == 1 ->
+        FunResp when tuple_size(FunResp) =:= 1 ->
             [<<"resp">>, FunResp];
         FunResp ->
             FunResp
@@ -352,7 +347,7 @@ to_binary({Data}) ->
     end,
     {lists:map(Pred, Data)};
 to_binary(Data) when is_list(Data) ->
-    lists:map(fun to_binary/1, Data);
+    [to_binary(D) || D <- Data];
 to_binary(null) ->
     null;
 to_binary(true) ->
diff --git a/src/couchdb/couch_os_process.erl b/src/couchdb/couch_os_process.erl
index f42e99a8..244a59f5 100644
--- a/src/couchdb/couch_os_process.erl
+++ b/src/couchdb/couch_os_process.erl
@@ -62,10 +62,9 @@ prompt(Pid, Data) ->
 writeline(OsProc, Data) when is_record(OsProc, os_proc) ->
     port_command(OsProc#os_proc.port, Data ++ "\n").
 
-readline(OsProc) when is_record(OsProc, os_proc) ->
+readline(#os_proc{} = OsProc) ->
     readline(OsProc, []).
-readline(OsProc, Acc) when is_record(OsProc, os_proc) ->
-    #os_proc{port=Port} = OsProc,
+readline(#os_proc{port = Port} = OsProc, Acc) ->
     receive
     {Port, {data, {noeol, Data}}} ->
         readline(OsProc, [Data|Acc]);
diff --git a/src/couchdb/couch_query_servers.erl b/src/couchdb/couch_query_servers.erl
index f94cc28b..9ab4ff5a 100644
--- a/src/couchdb/couch_query_servers.erl
+++ b/src/couchdb/couch_query_servers.erl
@@ -190,10 +190,7 @@ render_doc_show(Lang, ShowSrc, DocId, Doc, Req, Db) ->
         {DocId, nil} -> {{append_docid(DocId, JsonReqIn)}, null};
         _ -> {{append_docid(DocId, JsonReqIn)}, couch_doc:to_json_obj(Doc, [revs])}
     end,
-    try proc_prompt(Proc,
-        [<<"show">>, ShowSrc, JsonDoc, JsonReq]) of
-    FormResp ->
-        FormResp
+    try proc_prompt(Proc, [<<"show">>, ShowSrc, JsonDoc, JsonReq])
     after
         ok = ret_os_process(Proc)
     end.
@@ -207,10 +204,7 @@ render_doc_update(Lang, UpdateSrc, DocId, Doc, Req, Db) ->
         {DocId, nil} -> {{append_docid(DocId, JsonReqIn)}, null};
         _ -> {{append_docid(DocId, JsonReqIn)}, couch_doc:to_json_obj(Doc, [revs])}
     end,
-    try proc_prompt(Proc, 
-        [<<"update">>, UpdateSrc, JsonDoc, JsonReq]) of
-    FormResp ->
-        FormResp
+    try proc_prompt(Proc, [<<"update">>, UpdateSrc, JsonDoc, JsonReq])
     after
         ok = ret_os_process(Proc)
     end.
diff --git a/src/couchdb/couch_rep.erl b/src/couchdb/couch_rep.erl
index 23a44069..24b1557f 100644
--- a/src/couchdb/couch_rep.erl
+++ b/src/couchdb/couch_rep.erl
@@ -308,15 +308,15 @@ compare_rep_history([{S}|SourceRest], [{T}|TargetRest]=Target) ->
         end
     end.
 
-close_db(#http_db{})->
+close_db(#http_db{}) ->
     ok;
-close_db(Db)->
+close_db(Db) ->
     couch_db:close(Db).
 
-dbname(#http_db{} = Db) ->
-    Db#http_db.url;
-dbname(Db) ->
-    Db#db.name.
+dbname(#http_db{url = Url}) ->
+    Url;
+dbname(#db{name = Name}) ->
+    Name.
 
 dbinfo(#http_db{} = Db) ->
     {DbProps} = couch_rep_httpc:request(Db),
diff --git a/src/couchdb/couch_rep_att.erl b/src/couchdb/couch_rep_att.erl
index 04674fe2..6b576a01 100644
--- a/src/couchdb/couch_rep_att.erl
+++ b/src/couchdb/couch_rep_att.erl
@@ -16,9 +16,9 @@
 
 -include("couch_db.hrl").
 
-convert_stub(#att{data=stub} = Attachment, {#http_db{} = Db, Id, Rev}) ->
+convert_stub(#att{data=stub, name=Name} = Attachment,
+	     {#http_db{} = Db, Id, Rev}) ->
     {Pos, [RevId|_]} = Rev,
-    Name = Attachment#att.name,
     Request = Db#http_db{
         resource = lists:flatten([couch_util:url_encode(Id), "/",
             couch_util:url_encode(Name)]),
diff --git a/src/couchdb/couch_rep_httpc.erl b/src/couchdb/couch_rep_httpc.erl
index 60d44cab..4944f554 100644
--- a/src/couchdb/couch_rep_httpc.erl
+++ b/src/couchdb/couch_rep_httpc.erl
@@ -17,7 +17,7 @@
 -export([db_exists/1, db_exists/2, full_url/1, request/1, redirected_request/2,
     spawn_worker_process/1, spawn_link_worker_process/1]).
 
-request(Req) when is_record(Req, http_db) ->
+request(#http_db{} = Req) ->
     do_request(Req).
 
 do_request(#http_db{url=Url} = Req) when is_binary(Url) ->
diff --git a/src/couchdb/couch_rep_writer.erl b/src/couchdb/couch_rep_writer.erl
index ffe9768f..b86028ce 100644
--- a/src/couchdb/couch_rep_writer.erl
+++ b/src/couchdb/couch_rep_writer.erl
@@ -44,13 +44,13 @@ writer_loop(Parent, Reader, Target) ->
         writer_loop(Parent, Reader, Target)
     end.
 
-write_docs(#http_db{} = Db, Docs) ->
+write_docs(#http_db{headers = Headers} = Db, Docs) ->
     JsonDocs = [couch_doc:to_json_obj(Doc, [revs,attachments]) || Doc <- Docs],
     Request = Db#http_db{
         resource = "_bulk_docs",
         method = post,
         body = {[{new_edits, false}, {docs, JsonDocs}]},
-        headers = [{"x-couch-full-commit", "false"} | Db#http_db.headers]
+        headers = [{"x-couch-full-commit", "false"} | Headers]
     },
     ErrorsJson = case couch_rep_httpc:request(Request) of
     {FailProps} ->
@@ -58,16 +58,14 @@ write_docs(#http_db{} = Db, Docs) ->
     List when is_list(List) ->
         List
     end,
-    ErrorsList =
-    lists:map(
-        fun({Props}) ->
-            Id = proplists:get_value(<<"id">>, Props),
-            Rev = couch_doc:parse_rev(proplists:get_value(<<"rev">>, Props)),
-            ErrId = couch_util:to_existing_atom(
-                    proplists:get_value(<<"error">>, Props)),
-            Reason = proplists:get_value(<<"reason">>, Props),
-            {{Id, Rev}, {ErrId, Reason}}
-        end, ErrorsJson),
+    ErrorsList = [write_docs_1(V) || V <- ErrorsJson],
     {ok, ErrorsList};
 write_docs(Db, Docs) ->
     couch_db:update_docs(Db, Docs, [delay_commit], replicated_changes).
+
+write_docs_1({Props}) ->
+    Id = proplists:get_value(<<"id">>, Props),
+    Rev = couch_doc:parse_rev(proplists:get_value(<<"rev">>, Props)),
+    ErrId = couch_util:to_existing_atom(proplists:get_value(<<"error">>, Props)),
+    Reason = proplists:get_value(<<"reason">>, Props),
+    {{Id, Rev}, {ErrId, Reason}}.
diff --git a/src/couchdb/couch_stats_aggregator.erl b/src/couchdb/couch_stats_aggregator.erl
index d067f354..76620093 100644
--- a/src/couchdb/couch_stats_aggregator.erl
+++ b/src/couchdb/couch_stats_aggregator.erl
@@ -173,8 +173,8 @@ new_value(incremental, Value, Current) ->
 new_value(absolute, Value, _Current) ->
     Value.
 
-add_value(Time, Value, #aggregate{count=Count}=Agg) when Count < 1 ->
-    Samples = case Agg#aggregate.seconds of
+add_value(Time, Value, #aggregate{count=Count, seconds=Secs}=Agg) when Count < 1 ->
+    Samples = case Secs of
         0 -> [];
         _ -> [{Time, Value}]
     end,
@@ -233,8 +233,8 @@ rem_values(Time, Agg) ->
     end, Agg, Remove),
     Agg2#aggregate{samples=Keep}.
 
-rem_value(_Value, #aggregate{count=Count}=Agg) when Count =< 1 ->
-    #aggregate{seconds=Agg#aggregate.seconds};
+rem_value(_Value, #aggregate{count=Count, seconds=Secs}) when Count =< 1 ->
+    #aggregate{seconds=Secs};
 rem_value(Value, Agg) ->
     #aggregate{
         count=Count,
diff --git a/src/couchdb/couch_util.erl b/src/couchdb/couch_util.erl
index cdae0d4a..d02be8d9 100644
--- a/src/couchdb/couch_util.erl
+++ b/src/couchdb/couch_util.erl
@@ -49,11 +49,11 @@ start_driver(LibDir) ->
 
 % works like list_to_existing_atom, except can be list or binary and it
 % gives you the original value instead of an error if no existing atom.
-to_existing_atom(V) when is_list(V)->
+to_existing_atom(V) when is_list(V) ->
     try list_to_existing_atom(V) catch _ -> V end;
-to_existing_atom(V) when is_binary(V)->
+to_existing_atom(V) when is_binary(V) ->
     try list_to_existing_atom(?b2l(V)) catch _ -> V end;
-to_existing_atom(V) when is_atom(V)->
+to_existing_atom(V) when is_atom(V) ->
     V.
 
 
@@ -76,7 +76,7 @@ to_digit(N) when N < 10 -> $0 + N;
 to_digit(N)             -> $a + N-10.
 
 
-parse_term(Bin) when is_binary(Bin)->
+parse_term(Bin) when is_binary(Bin) ->
     parse_term(binary_to_list(Bin));
 parse_term(List) ->
     {ok, Tokens, _} = erl_scan:string(List ++ "."),
@@ -148,14 +148,14 @@ ascii_lower([], Acc) ->
     lists:reverse(Acc);
 ascii_lower([Char | RestString], Acc) when Char >= $A, Char =< $B ->
     ascii_lower(RestString, [Char + ($a-$A) | Acc]);
-ascii_lower([Char | RestString], Acc)->
+ascii_lower([Char | RestString], Acc) ->
     ascii_lower(RestString, [Char | Acc]).
 
 % Is a character whitespace?
-is_whitespace($\s)-> true;
-is_whitespace($\t)-> true;
-is_whitespace($\n)-> true;
-is_whitespace($\r)-> true;
+is_whitespace($\s) -> true;
+is_whitespace($\t) -> true;
+is_whitespace($\n) -> true;
+is_whitespace($\r) -> true;
 is_whitespace(_Else) -> false.
 
 
@@ -206,9 +206,8 @@ collate(A, B, Options) when is_binary(A), is_binary(B) ->
         true -> 1; % Case insensitive
         false -> 0 % Case sensitive
     end,
-
-    SizeA = size(A),
-    SizeB = size(B),
+    SizeA = byte_size(A),
+    SizeB = byte_size(B),
     Bin = <<SizeA:32/native, A/binary, SizeB:32/native, B/binary>>,
     [Result] = erlang:port_control(drv_port(), Operation, Bin),
     % Result is 0 for lt, 1 for eq and 2 for gt. Subtract 1 to return the
@@ -227,9 +226,7 @@ should_flush(MemThreshHold) ->
         {memory, ProcMem2} = process_info(self(), memory),
         BinMem2 = lists:foldl(fun({_Id, Size, _NRefs}, Acc) -> Size+Acc end,
             0, element(2,process_info(self(), binary))),
-        if ProcMem2+BinMem2 > MemThreshHold ->
-            true;
-        true -> false end;
+        ProcMem2+BinMem2 > MemThreshHold;
     true -> false end.
 
 
@@ -287,7 +284,7 @@ encodeBase64Url(<<>>, Acc) ->
 %%
 %% decodeBase64(BinaryChars) -> Binary
 %%
-decodeBase64(Cs) when is_list(Cs)->
+decodeBase64(Cs) when is_list(Cs) ->
     decodeBase64(list_to_binary(Cs));
 decodeBase64(Cs) ->
     decode1(Cs, <<>>).
@@ -304,7 +301,7 @@ decode1(<<C1, C2, C3, C4, Cs/binary>>, Acc) ->
 decode1(<<>>, Acc) ->
     Acc.
 
-decodeBase64Url(Cs) when is_list(Cs)->
+decodeBase64Url(Cs) when is_list(Cs) ->
     decodeBase64Url(list_to_binary(Cs));
 decodeBase64Url(Cs) ->
     decode1Url(Cs, <<>>).
diff --git a/src/couchdb/couch_view.erl b/src/couchdb/couch_view.erl
index 778756ef..f80ce434 100644
--- a/src/couchdb/couch_view.erl
+++ b/src/couchdb/couch_view.erl
@@ -89,9 +89,9 @@ cleanup_index_files(Db) ->
     RegExp = "("++ string:join(Sigs, "|") ++")",
 
     % filter out the ones in use
-    DeleteFiles = lists:filter(fun(FilePath) ->
-            re:run(FilePath, RegExp, [{capture, none}]) == nomatch
-        end, FileList),
+    DeleteFiles = [FilePath
+		   || FilePath <- FileList,
+		      re:run(FilePath, RegExp, [{capture, none}]) =:= nomatch],
     % delete unused files
     ?LOG_DEBUG("deleting unused view index files: ~p",[DeleteFiles]),
     [file:delete(File)||File <- DeleteFiles],
@@ -369,12 +369,10 @@ less_json_ids({JsonA, IdA}, {JsonB, IdB}) ->
 less_json(A, B) ->
     TypeA = type_sort(A),
     TypeB = type_sort(B),
-    if
-    TypeA == TypeB ->
-        Less = less_same_type(A,B),
-        Less;
-    true ->
-        TypeA < TypeB
+    if TypeA == TypeB ->
+	    less_same_type(A, B);
+       true ->
+	    TypeA < TypeB
     end.
 
 type_sort(V) when is_atom(V) -> 0;
diff --git a/src/couchdb/couch_view_compactor.erl b/src/couchdb/couch_view_compactor.erl
index ad217d97..895556bf 100644
--- a/src/couchdb/couch_view_compactor.erl
+++ b/src/couchdb/couch_view_compactor.erl
@@ -49,7 +49,7 @@ compact_group(Group, EmptyGroup) ->
     couch_task_status:add_task(<<"View Group Compaction">>, TaskName, <<"">>),
 
     Fun = fun(KV, {Bt, Acc, TotalCopied}) ->
-        if TotalCopied rem 10000 == 0 ->
+        if TotalCopied rem 10000 =:= 0 ->
             couch_task_status:update("Copied ~p of ~p Ids (~p%)",
                 [TotalCopied, Count, (TotalCopied*100) div Count]),
             {ok, Bt2} = couch_btree:add(Bt, lists:reverse([KV|Acc])),
@@ -81,7 +81,7 @@ compact_view(View, EmptyView) ->
 
     %% Key is {Key,DocId}
     Fun = fun(KV, {Bt, Acc, TotalCopied}) ->
-        if TotalCopied rem 10000 == 0 ->
+        if TotalCopied rem 10000 =:= 0 ->
             couch_task_status:update("View #~p: copied ~p of ~p KVs (~p%)",
                 [View#view.id_num, TotalCopied, Count, (TotalCopied*100) div Count]),
             {ok, Bt2} = couch_btree:add(Bt, lists:reverse([KV|Acc])),
diff --git a/src/couchdb/couch_view_updater.erl b/src/couchdb/couch_view_updater.erl
index 475f59ac..aa7d98fc 100644
--- a/src/couchdb/couch_view_updater.erl
+++ b/src/couchdb/couch_view_updater.erl
@@ -16,6 +16,8 @@
 
 -include("couch_db.hrl").
 
+-spec update(_, #group{}) -> no_return().
+
 update(Owner, Group) ->
     #group{
         db = #db{name=DbName} = Db,
diff --git a/src/couchdb/couch_work_queue.erl b/src/couchdb/couch_work_queue.erl
index e00b52a3..ca9445d3 100644
--- a/src/couchdb/couch_work_queue.erl
+++ b/src/couchdb/couch_work_queue.erl
@@ -52,7 +52,7 @@ terminate(_Reason, #q{work_waiter=WW}) ->
     gen_server:reply(WW, closed).
     
 handle_call({queue, Item}, From, #q{work_waiter=nil}=Q0) ->
-    Q = Q0#q{size=Q0#q.size + size(term_to_binary(Item)),
+    Q = Q0#q{size=Q0#q.size + byte_size(term_to_binary(Item)),
                 items=Q0#q.items + 1,
                 buffer=[Item | Q0#q.buffer]},
     case (Q#q.size >= Q#q.max_size) orelse