From ee8919420de5088e02e0ed056ceae2b4a2088925 Mon Sep 17 00:00:00 2001
From: Andrew Thompson <andrew@hijacked.us>
Date: Fri, 25 Jan 2013 13:53:27 -0500
Subject: [PATCH] Support reading mustache 'lists' from files

This commit add support for reading mustache 'lists' from files, so you
can use the list section functionality when templating things.

An example of the list syntax is as follows:

{package_commands, {list, [[{name, "riak"}], [{name, "riak-admin"}], [{name, "search-cmd"}]]}}.

Then you can, for each of the list elements, render some text:

{{#package_commands}}
chmod +x bin/{{name}}
{{/package_commands}}
---
 src/rebar_templater.erl | 24 +++++++++++++++++-------
 1 file changed, 17 insertions(+), 7 deletions(-)

diff --git a/src/rebar_templater.erl b/src/rebar_templater.erl
index 0e1eef1..5fac9b9 100644
--- a/src/rebar_templater.erl
+++ b/src/rebar_templater.erl
@@ -81,6 +81,9 @@ resolve_variables([], Dict) ->
 resolve_variables([{Key, Value0} | Rest], Dict) when is_list(Value0) ->
     Value = render(list_to_binary(Value0), Dict),
     resolve_variables(Rest, dict:store(Key, Value, Dict));
+resolve_variables([{Key, {list, Dicts}} | Rest], Dict) when is_list(Dicts) ->
+    %% just un-tag it so mustache can use it
+    resolve_variables(Rest, dict:store(Key, Dicts, Dict));
 resolve_variables([_Pair | Rest], Dict) ->
     resolve_variables(Rest, Dict).
 
@@ -134,14 +137,14 @@ create1(Config, TemplateId) ->
                    undefined ->
                        Context0;
                    File ->
-                       case file:consult(File) of
-                           {ok, Terms} ->
-                               %% TODO: Cleanup/merge with similar code in rebar_reltool
-                               M = fun(_Key, _Base, Override) -> Override end,
-                               dict:merge(M, Context0, dict:from_list(Terms));
+                       case consult(load_file([], file, File)) of
                            {error, Reason} ->
                                ?ABORT("Unable to load template_vars from ~s: ~p\n",
-                                      [File, Reason])
+                                      [File, Reason]);
+                           Terms ->
+                               %% TODO: Cleanup/merge with similar code in rebar_reltool
+                               M = fun(_Key, _Base, Override) -> Override end,
+                               dict:merge(M, Context0, dict:from_list(Terms))
                        end
                end,
 
@@ -275,7 +278,7 @@ consult(Cont, Str, Acc) ->
             case Result of
                 {ok, Tokens, _} ->
                     {ok, Term} = erl_parse:parse_term(Tokens),
-                    consult([], Remaining, [Term | Acc]);
+                    consult([], Remaining, [maybe_dict(Term) | Acc]);
                 {eof, _Other} ->
                     lists:reverse(Acc);
                 {error, Info, _} ->
@@ -286,6 +289,13 @@ consult(Cont, Str, Acc) ->
     end.
 
 
+maybe_dict({Key, {list, Dicts}}) ->
+    %% this is a 'list' element; a list of lists representing dicts
+    {Key, {list, [dict:from_list(D) || D <- Dicts]}};
+maybe_dict(Term) ->
+    Term.
+
+
 write_file(Output, Data, Force) ->
     %% determine if the target file already exists
     FileExists = filelib:is_regular(Output),