Fix decode/1 crash on non-JSON strings from search input

lib/live_select.ex

@@ -543,15 +543,29 @@ defmodule LiveSelect do
 
     iex> decode(["{\"name\":\"New York City\",\"pos\":[-74.00597,40.71427]}","{\"name\":\"Stockholm\",\"pos\":[18.06871,59.32938]}"])
     [%{"name" => "New York City","pos" => [-74.00597,40.71427]}, %{"name" => "Stockholm","pos" => [18.06871,59.32938]}]
+
+  Non-JSON strings (e.g. raw text from a search input) are returned as-is:
+
+    iex> decode("Glon")
+    "Glon"
+
+    iex> decode(["Berlin", "Rome"])
+    ["Berlin", "Rome"]
   """
   def decode(selection) do
     json = Phoenix.json_library()
 
     case selection do
       nil -> []
       "" -> nil
-      selection when is_list(selection) -> Enum.map(selection, &json.decode!/1)
-      selection -> json.decode!(selection)
+      selection when is_list(selection) -> Enum.map(selection, &safe_decode(json, &1))
+      selection -> safe_decode(json, selection)
     end
   end
+
+  defp safe_decode(json, value) do
+    json.decode!(value)
+  rescue
+    _ -> value
+  end
 end

test/live_select/decode_test.exs

@@ -0,0 +1,42 @@
+defmodule LiveSelect.DecodeTest do
+  @moduledoc false
+
+  use ExUnit.Case, async: true
+
+  describe "decode/1" do
+    test "decodes nil to empty list" do
+      assert LiveSelect.decode(nil) == []
+    end
+
+    test "decodes empty string to nil" do
+      assert LiveSelect.decode("") == nil
+    end
+
+    test "decodes a JSON-encoded map" do
+      assert LiveSelect.decode(~s({"name":"Berlin","pos":[13.41,52.52]})) ==
+               %{"name" => "Berlin", "pos" => [13.41, 52.52]}
+    end
+
+    test "decodes a list of JSON-encoded maps" do
+      assert LiveSelect.decode([
+               ~s({"name":"Berlin"}),
+               ~s({"name":"Rome"})
+             ]) == [
+               %{"name" => "Berlin"},
+               %{"name" => "Rome"}
+             ]
+    end
+
+    test "returns plain string as-is when it's not valid JSON" do
+      assert LiveSelect.decode("Glon") == "Glon"
+    end
+
+    test "returns string with special characters as-is when not valid JSON" do
+      assert LiveSelect.decode("São Paulo") == "São Paulo"
+    end
+
+    test "returns list elements as-is when they are not valid JSON" do
+      assert LiveSelect.decode(["Berlin", "Rome"]) == ["Berlin", "Rome"]
+    end
+  end
+end