Merge pull request #6 from edgurgel/add-access-to-arrays

Add access support to arrays through Solid.Argument

lib/solid/argument.ex

@@ -13,11 +13,23 @@ defmodule Solid.Argument do
   123
   iex> Solid.Argument.get({:value, "value"}, %Solid.Context{})
   "value"
+  iex> Solid.Argument.get({:field, "key", [{:access, 1},{:access, 1}]}, %Solid.Context{vars: %{"key" => [1, [1,2,3], 3]}})
+  2
+  iex> Solid.Argument.get({:field, "key", [{:access, 1}]}, %Solid.Context{vars: %{"key" => "a string"}})
+  nil
   """
-  @spec get({:field, String.t} | {:value, term}, Context.t) :: term
+  @spec get({:field, String.t} | {:field, String.t, [{:access, non_neg_integer}]} | {:value, term}, Context.t) :: term
+  def get({:value, val}, _hash), do: val
   def get({:field, key}, %Context{vars: vars}) do
     key = key |> String.split(".")
     get_in(vars, key)
   end
-  def get({:value, val}, _hash), do: val
+  def get({:field, key, accesses}, context) do
+    value = get({:field, key}, context)
+    Enum.reduce(accesses, value,
+                fn {:access, index}, acc when is_list(acc) ->
+                     Enum.at(acc, index)
+                   _, _ -> nil
+                end)
+  end
 end

lib/solid/tag.ex

@@ -58,7 +58,7 @@ defmodule Solid.Tag do
     end
   end
 
-  defp do_eval({:assign_exp, field, argument}, context) do
+  defp do_eval({:assign_exp, {:field, field}, argument}, context) do
     context = %{context | vars: Map.put(context.vars, field, Argument.get(argument, context))}
     {nil, context}
   end

src/solid_parser.peg

@@ -111,7 +111,19 @@ case Node of
   [Arg1, Args] -> [Arg1 | [Arg || [_, _, _, Arg] <- Args]]
 end
 `;
-argument <- value:value / field:field ~;
+argument <- value:value / field ~;
+field    <- [0-9a-zA-Z\.]* access* `
+ case Node of
+   [FieldName | [[]]] -> {field, iolist_to_binary(FieldName)};
+   [FieldName | [Accesses]] ->
+     {field, iolist_to_binary(FieldName), Accesses}
+ end
+`;
+access <- "[" int "]" `
+case Node of
+  [_, Integer, _] -> {access, list_to_integer(binary_to_list(iolist_to_binary(Integer)))}
+end
+`;
 value <- space (string / number / true / false / null) space `lists:nth(2, Node)`;
 string <- single_quoted_string / double_quoted_string `
 iolist_to_binary(proplists:get_value(string, Node))
@@ -136,7 +148,6 @@ case           <- "case" ~;
 when           <- "when" ~;
 endcase        <- "endcase" ~;
 assign         <- "assign" ~;
-field          <- [0-9a-zA-Z\.]* `iolist_to_binary(Node)`;
 filter         <- [a-zA-Z]* `iolist_to_binary(Node)`;
 space          <- [ \t\n\s\r]* `{space, iolist_to_binary(Node)}`;
 

test/cases/023/input.json

@@ -0,0 +1 @@
+{ "var" : [1, 2, 3]}

test/cases/023/input.liquid

@@ -0,0 +1 @@
+{{ var[1] }}

test/cases/024/input.json

@@ -0,0 +1 @@
+{ "var" : [["a", "b", "c"], [1, 2, 3]]}

test/cases/024/input.liquid

@@ -0,0 +1,3 @@
+{{ var[0][1] }}
+{{ var[1][1] }}
+{{ var[12] }}

test/cases/025/input.json

@@ -0,0 +1 @@
+{}

test/cases/025/input.liquid

@@ -0,0 +1,3 @@
+{{ var[0][1] }}
+{{ var[1][1] }}
+{{ var[12] }}

test/cases/026/input.json

@@ -0,0 +1 @@
+{ "var" : "string" }

test/cases/026/input.liquid

@@ -0,0 +1,3 @@
+{{ var[0][1] }}
+{{ var[1][1] }}
+{{ var[12] }}

test/cases/027/input.json

@@ -0,0 +1 @@
+{ "var" : ["a", "b", "c"] }

test/cases/027/input.liquid

@@ -0,0 +1 @@
+{{ var[1] | upcase }}

test/cases/028/input.json

@@ -0,0 +1 @@
+{ "var" : ["a", "b", "c"] }

test/cases/028/input.liquid

@@ -0,0 +1,3 @@
+{% if var[1] == "b" %}
+  letter b
+{% endif %}