From: Peter Lemenkov <lemenkov@gmail.com>
Date: Mon, 7 Mar 2016 16:26:49 +0300
Subject: [PATCH] No rebar_mustache available

Signed-off-by: Peter Lemenkov <lemenkov@gmail.com>

diff --git a/src/cuttlefish_unit.erl b/src/cuttlefish_unit.erl
index e67826f..7736abd 100644
--- a/src/cuttlefish_unit.erl
+++ b/src/cuttlefish_unit.erl
@@ -294,110 +294,14 @@ path([H|T], Proplist) when is_list(H)->
 -spec render_template(FileName :: file:name_all(), Context :: mustache_ctx())
             -> string().
 render_template(FileName, Context) ->
-    %% The mustache module may only be available in the context of a rebar run.
-    case find_mustache() of
-        false ->
-            erlang:error(
-                "No suitable mustache module loaded. "
-                "Run this test in a rebar context.");
-        Mod ->
-            {ok, Bin} = file:read_file(FileName),
-            render_template(Mod, Bin, Context)
-    end.
+    {ok, Bin} = file:read_file(FileName),
+    unicode:characters_to_list(
+        bbmustache:render(Bin, [mkey_string(Elem) || Elem <- Context])).
 
 %% ===================================================================
 %% Internal
 %% ===================================================================
 
--spec render_template(
-        Mustache    :: module(),
-        Template    :: binary(),
-        Context     :: mustache_ctx())
-            -> string().
-%
-% Even where we're matching on the module, always use the Module variable so
-% xref and dialyzer don't complain. If running in Rebar there will be a
-% suitable module available at runtime, but usually there won't be an explicit
-% project dependency on one.
-%
-% Unicode support is sketchy, as it is throughout cuttlefish. Someday...
-%
-render_template(bbmustache = Mustache, Template, Context) ->
-    % It's unclear whether there could be supplementary UTF-8 bytes that could
-    % be misinterpreted as relevant characters by the scanner, but as noted
-    % above we're not putting much effort into Unicode for now.
-    % The render call raises an error if there's a problem, so no need to
-    % check return pattern.
-    unicode:characters_to_list(
-        Mustache:render(Template, mustache_context(Mustache, Context)));
-
-render_template(Mustache, Template, Context) ->
-    % Previous versions of this file escaped the template, but that actually
-    % seems to break things I've tested, so it's just converted to a list.
-    Data = case unicode:characters_to_list(Template, utf8) of
-        Utf8 when erlang:is_list(Utf8) ->
-            Utf8;
-        _ ->
-            % Not legal UTF-8, treat it as an 8-bit ISO-8859 encoding, which
-            % will always succeed but _may_ be improperly mapped if it's not
-            % specifically Latin-1. However, all of the punctuation characters
-            % the scanner cares about should be fine.
-            unicode:characters_to_list(Template, latin1)
-    end,
-    Mustache:render(Data, mustache_context(Mustache, Context)).
-
--spec find_mustache() -> module() | false.
-%
-% Finds a module that is likely to be a mustache implementation that
-% render_template/3 knows how to use.
-% Once identified, the module is cached in the process environment, so it'll
-% be lost when the process goes away, which should coincide with eunit test
-% setup/teardown when the available modules might change.
-%
-find_mustache() ->
-    Key = {?MODULE, mustache_module},
-    case erlang:get(Key) of
-        undefined ->
-            Ret = find_mustache([bbmustache, mustache, rebar_mustache]),
-            _ = erlang:put(Key, Ret),
-            Ret;
-        Val ->
-            Val
-    end.
-
--spec find_mustache(Mods :: [module()]) -> module() | false.
-%
-% Let find_mustache/0 call this, not much use anywhere else.
-%
-find_mustache([Mod | Mods]) ->
-    case code:ensure_loaded(Mod) of
-        {module, _} ->
-            case erlang:function_exported(Mod, render, 2) of
-                true ->
-                    Mod;
-                _ ->
-                    find_mustache(Mods)
-            end;
-        _ ->
-            find_mustache(Mods)
-    end;
-find_mustache([]) ->
-    false.
-
--spec mustache_context(Module :: module(), Context :: mustache_ctx()) -> term().
-%
-% Returns an appropriate mapping context for the mustache Module.
-%
-mustache_context(bbmustache, Context) ->
-    % Despite what the docs say, bbmustache seems to need the keys to be
-    % strings. This _could_ be limited to the pre-OTP-17 code, but we need R16
-    % compatibility during the transition so I'm not going to sweat it.
-    [mkey_string(Elem) || Elem <- Context];
-mustache_context(rebar_mustache, Context) ->
-    dict:from_list(Context);
-mustache_context(_, Context) ->
-    Context.
-
 -spec mkey_string(Elem :: mustache_def()) -> {string(), mustache_val()}.
 %
 % Ensure the Key of the specified Elem is a string.