Merge branch 'Better-enumerable-type-check'

Author: keathley

.gitignore

@@ -22,3 +22,5 @@ erl_crash.dump
 # Ignore package tarball (built via "mix hex.build").
 norm-*.tar
 
+# Elixir Language Server (e.g. for VS Code users).
+/.elixir_ls

lib/norm/spec/collection.ex

@@ -12,7 +12,9 @@ defmodule Norm.Spec.Collection do
     alias Norm.Conformer.Conformable
 
     def conform(%{spec: spec, opts: opts}, input, path) do
-      with :ok <- check_distinct(input, path, opts),
+      with :ok <- check_enumerable(input, path, opts),
+           :ok <- check_map_of(input, path, opts),
+           :ok <- check_distinct(input, path, opts),
            :ok <- check_counts(input, path, opts) do
         results =
           input
@@ -60,6 +62,29 @@ defmodule Norm.Spec.Collection do
         :ok
       end
     end
+
+    defp check_enumerable(input, path, _opts) do
+      if Enumerable.impl_for(input) == nil do
+        {:error, [Conformer.error(path, input, "not enumerable")]}
+      else
+        :ok
+      end
+  end
+
+    defp check_map_of(input, path, opts) do
+      cond do
+        # if coll_of was used, accept every kind of list
+        opts[:into] == [] ->
+          :ok
+
+        # in case of map_of, check the format of the enumerable
+        Enum.all?(input, &match?({_, _}, &1)) ->
+          :ok
+
+        true ->
+          {:error, [Conformer.error(path, input, "not a map")]}
+      end
+    end
   end
 
   if Code.ensure_loaded?(StreamData) do

test/norm_test.exs

@@ -161,6 +161,24 @@ defmodule NormTest do
       assert %{1 => :foo, 2 => :bar} == conform!(%{1 => :foo, 2 => :bar}, spec)
     end
 
+    test "doesn't throw for non-enumerable inputs" do
+      spec = map_of(spec(is_integer()), spec(is_atom()))
+
+      assert {:error, errors} = conform("not-a-map!", spec)
+      assert errors == [
+        %{spec: "not enumerable", input: "not-a-map!", path: []}
+      ]
+    end
+
+    test "doesn't throw for list inputs" do
+      spec = map_of(spec(is_integer()), spec(is_atom()))
+
+      assert {:error, errors} = conform([1, 2, 3], spec)
+      assert errors == [
+        %{spec: "not a map", input: [1, 2, 3], path: []}
+      ]
+    end
+
     property "can be generated" do
       check all m <- gen(map_of(spec(is_integer()), spec(is_atom()))) do
         assert is_map(m)
@@ -181,6 +199,15 @@ defmodule NormTest do
       ]
     end
 
+    test "doesn't throw for non-enumerable inputs" do
+      spec = coll_of(spec(is_integer()))
+
+      assert {:error, errors} = conform("not-a-collection!", spec)
+      assert errors == [
+        %{spec: "not enumerable", input: "not-a-collection!", path: []}
+      ]
+    end
+
     test "conforming returns the conformed values" do
       spec = coll_of(schema(%{name: spec(is_binary())}))
       input = [