diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/rebar_state.erl | 58 |
1 files changed, 57 insertions, 1 deletions
diff --git a/src/rebar_state.erl b/src/rebar_state.erl index 008f202..eced383 100644 --- a/src/rebar_state.erl +++ b/src/rebar_state.erl @@ -240,7 +240,7 @@ merge_opts(NewOpts, OldOpts) -> true -> NewValue; false -> - lists:umerge(lists:sort(NewValue), lists:sort(OldValue)) + tup_umerge(lists:sort(NewValue), lists:sort(OldValue)) end; (_Key, NewValue, _OldValue) -> NewValue @@ -362,3 +362,59 @@ add_hook(pre, {PreHooks, PostHooks}, Hook) -> {[Hook | PreHooks], PostHooks}; add_hook(post, {PreHooks, PostHooks}, Hook) -> {PreHooks, [Hook | PostHooks]}. + +%% Custom merge functions. The objective is to behave like lists:umerge/2, +%% except that we also compare the merge elements based on the key if they're a +%% tuple, such that `{key, val1}' is always prioritized over `{key, val0}' if +%% the former is from the 'new' list. +%% +%% This lets us apply proper overrides to list of elements according to profile +%% priority. +tup_umerge([], Olds) -> + Olds; +tup_umerge(News, Olds) -> + [ENew|ENews] = expand(News), + EOlds = expand(Olds), + unexpand(lists:reverse(umerge(ENews, EOlds, [], ENew))). + +%% Expand values, so they `key' is now `{key, key}', and so that +%% `{key, val}' is now `{key, {key, val}'. This allows us to compare +%% possibly only on the total key or the value itself. +expand([]) -> []; +expand([Tup|T]) when is_tuple(Tup) -> [{element(1, Tup), Tup} | expand(T)]; +expand([H|T]) -> [{H,H} | expand(T)]. + +%% Go back to unexpanded form. +unexpand(List) -> [element(2, X) || X <- List]. + +%% This is equivalent to umerge2_2 in the stdlib, except we use the expanded +%% value/key only to compare +umerge(News, [{KOld,_}=Old|Olds], Merged, {KCmp, _} = Cmp) when KCmp =< KOld -> + umerge(News, Olds, [Cmp | Merged], Cmp, Old); +umerge(News, [Old|Olds], Merged, Cmp) -> + umerge(News, Olds, [Old | Merged], Cmp); +umerge(News, [], Merged, Cmp) -> + lists:reverse(News, [Cmp | Merged]). + +%% Similar to stdlib's umerge2_1 in the stdlib, except that when the expanded +%% value/keys compare equal, we check if the element is a full dupe to clear it +%% (like the stdlib function does) or otherwise keep the duplicate around in +%% an order that prioritizes 'New' elements. +umerge([{KNew,_}=New|News], Olds, Merged, _CmpMerged, {KCmp,_}=Cmp) when KNew =< KCmp -> + umerge(News, Olds, [New | Merged], New, Cmp); +umerge([{KNew,_}=New|News], Olds, Merged, {KCmp,_}=CmpMerged, Cmp) when KNew == KCmp -> + if New == CmpMerged -> + umerge(News, Olds, Merged, New); + New =/= CmpMerged -> % this is where we depart from the stdlib! + umerge(News, Olds, [New | Merged], New, Cmp) + end; +umerge([New|News], Olds, Merged, _CmpMerged, Cmp) -> % > + umerge(News, Olds, [Cmp | Merged], New); +umerge([], Olds, Merged, {KCmpM,_}=CmpMerged, {KCmp,_}=Cmp) when KCmpM =:= KCmp -> + if CmpMerged == Cmp -> + lists:reverse(Olds, Merged); + CmpMerged =/= Cmp -> % We depart from stdlib here too! + lists:reverse(Olds, [Cmp | Merged]) + end; +umerge([], Olds, Merged, _CmpMerged, Cmp) -> + lists:reverse(Olds, [Cmp | Merged]). |