test: cover Aprsme.Is TCP data buffering and deployment init

test/aprsme/deployment_notifier_test.exs

@@ -40,4 +40,11 @@ defmodule Aprsme.DeploymentNotifierTest do
       assert_receive {:new_deployment, %{deployed_at: ^new_deploy}}, 500
     end
   end
+
+  describe "init/1" do
+    test "schedules a check and stores the current deployed_at in state" do
+      assert {:ok, %{deployed_at: %DateTime{}}} = DeploymentNotifier.init([])
+      # The 30s check is scheduled — we don't wait for it.
+    end
+  end
 end

test/aprsme/is_test.exs

@@ -410,6 +410,40 @@ defmodule Aprsme.IsTest do
     end
   end
 
+  describe "handle_info({:tcp, socket, data}, state) buffer edge cases" do
+    test "routes a single newline-terminated line through dispatch" do
+      ensure_ets_table()
+      state = build_state()
+
+      raw_line = "N0CALL>APRS,WIDE1-1:>Hello\r\n"
+
+      capture_log(fn ->
+        {:noreply, new_state} = Aprsme.Is.handle_info({:tcp, :fake_socket, raw_line}, state)
+        assert new_state.buffer == ""
+      end)
+    end
+
+    test "keeps incomplete trailing data in buffer" do
+      ensure_ets_table()
+      state = build_state()
+
+      capture_log(fn ->
+        {:noreply, new_state} = Aprsme.Is.handle_info({:tcp, :fake_socket, "partial"}, state)
+        assert new_state.buffer == "partial"
+      end)
+    end
+
+    test "concatenates previous buffer + new data for a complete line" do
+      ensure_ets_table()
+      state = build_state(%{buffer: "prefix"})
+
+      capture_log(fn ->
+        {:noreply, new_state} = Aprsme.Is.handle_info({:tcp, :fake_socket, "suffix\n"}, state)
+        assert new_state.buffer == ""
+      end)
+    end
+  end
+
   describe "terminate/2" do
     test "terminates cleanly with nil socket" do
       state = build_state(%{socket: nil})