Handle attempt to call :remove_link with not existing pad

lib/membrane/core/parent/child_life_controller/link_utils.ex

@@ -34,18 +34,24 @@ defmodule Membrane.Core.Parent.ChildLifeController.LinkUtils do
 
   @spec remove_link(Membrane.Child.name_t(), Pad.ref_t(), Parent.state_t()) :: Parent.state_t()
   def remove_link(child_name, pad_ref, state) do
-    {_link_id, link} =
-      Enum.find(state.links, fn {_link_id, link} ->
-        [link.from, link.to]
-        |> Enum.any?(&(&1.child == child_name and &1.pad_ref == pad_ref))
-      end)
+    Enum.find(state.links, fn {_id, link} ->
+      [link.from, link.to]
+      |> Enum.any?(&(&1.child == child_name and &1.pad_ref == pad_ref))
+    end)
+    |> case do
+      {_id, %Link{} = link} ->
+        for endpoint <- [link.from, link.to] do
+          Message.send(endpoint.pid, :handle_unlink, endpoint.pad_ref)
+        end
 
-    for endpoint <- [link.from, link.to] do
-      Message.send(endpoint.pid, :handle_unlink, endpoint.pad_ref)
-    end
+        links = Map.delete(state.links, link.id)
+        Map.put(state, :links, links)
 
-    links = Map.delete(state.links, link.id)
-    Map.put(state, :links, links)
+      nil ->
+        raise LinkError, """
+        Attempted to unlink pad #{inspect(pad_ref)} of child #{inspect(child_name)}, but this child does not have this pad
+        """
+    end
   end
 
   @spec unlink_element(Membrane.Child.name_t(), Parent.state_t()) :: Parent.state_t()

test/membrane/integration/linking_test.exs

@@ -387,8 +387,8 @@ defmodule Membrane.Integration.LinkingTest do
   test "Parent successfully unlinks children with dynamic pads using :remove_link action" do
     structure =
       [
-        child(:source, __MODULE__.Element)
-        |> child(:sink, __MODULE__.Element)
+        child(:source, __MODULE__.Element),
+        child(:sink, __MODULE__.Element)
       ] ++
         Enum.map(1..10, fn i ->
           get_child(:source)
@@ -418,13 +418,13 @@ defmodule Membrane.Integration.LinkingTest do
   end
 
   defp assert_pad_removed(pipeline, id) do
-    assert_pipeline_notified(pipeline, :source, {:handle_pad_removed, Pad.ref(:output, ^id)}, 1)
-    assert_pipeline_notified(pipeline, :sink, {:handle_pad_removed, Pad.ref(:input, ^id)}, 1)
+    assert_pipeline_notified(pipeline, :source, {:handle_pad_removed, Pad.ref(:output, ^id)})
+    assert_pipeline_notified(pipeline, :sink, {:handle_pad_removed, Pad.ref(:input, ^id)})
   end
 
   defp refute_pad_removed(pipeline, id) do
-    refute_pipeline_notified(pipeline, :source, {:handle_pad_removed, Pad.ref(:output, ^id)}, 1)
-    refute_pipeline_notified(pipeline, :sink, {:handle_pad_removed, Pad.ref(:input, ^id)}, 1)
+    refute_pipeline_notified(pipeline, :source, {:handle_pad_removed, Pad.ref(:output, ^id)}, 10)
+    refute_pipeline_notified(pipeline, :sink, {:handle_pad_removed, Pad.ref(:input, ^id)}, 10)
   end
 
   defp get_child_pid(ref, parent_pid) do