chore: avoid re-resolving a query in dynamic port bindings if the current selection matches

lib/syskit/dynamic_port_binding.rb

@@ -99,6 +99,10 @@ def attach_to_task(task)
         #   the port was updated, and false otherwise. The tuple's second element
         #   is the new resolved port which may be nil if no ports can be found
         def update
+            if @resolved_port && @port_resolver&.current_selection_valid?(@resolved_port)
+                return false, @resolved_port
+            end
+
             port = @port_resolver&.update
             return false, @resolved_port if @resolved_port == port
 
@@ -294,6 +298,10 @@ def initialize(plan, matcher)
                 @last_provider_task = nil
             end
 
+            def current_selection_valid?(port)
+                @matcher === port
+            end
+
             def update
                 port = @matcher.each_in_plan(@plan).first
                 port&.to_actual_port
@@ -319,6 +327,10 @@ def initialize(port)
                 @port = port
             end
 
+            def current_selection_valid?(port)
+                !!port.component.plan
+            end
+
             def update
                 @port if @port.component.plan
             end
@@ -337,6 +349,10 @@ def initialize(port)
                 @port = port
             end
 
+            def current_selection_valid?(port)
+                !!port.component.to_task.plan
+            end
+
             def update
                 @port if @port.component.to_task.plan
             end

lib/syskit/queries/port_matcher.rb

@@ -57,9 +57,9 @@ def with_type(type)
             def ===(port)
                 return unless port.kind_of?(Port)
 
-                (@name_filter === object.name) &&
-                    (!@type_filter || @type_filter == object.type) &&
-                    (@component_matcher === object.component)
+                (@name_filter === port.name) &&
+                    (!@type_filter || @type_filter == port.type) &&
+                    (@component_matcher === port.component)
             end
 
             def each_in_plan(plan, &block)

test/queries/test_port_matcher.rb

@@ -30,6 +30,13 @@ module Queries
                                      PortMatcher.new(@task_m).with_name("out_d")
             end
 
+            it "can find ports with ===" do
+                plan.add(task = @task_m.new)
+                matcher = PortMatcher.new(@task_m).with_name("out_d")
+                assert matcher === task.out_d_port
+                refute matcher === task.out_f_port
+            end
+
             it "optionally allows to filter with a name pattern" do
                 plan.add(task = @task_m.new)
                 assert_matcher_finds [task.out_d_port, task.out_f_port],