day20, modules state comparations

day20/modules.go

@@ -27,6 +27,7 @@ type Signal struct {
 type Module interface {
 	Receive(s Signal) []Signal
 	Outputs() []string
+	StateSnapshot() string
 }
 
 // Modules
@@ -71,6 +72,10 @@ func (ff *FlipFlop)String() string {
 	return fmt.Sprintf("[flip-flop '%s' (on: %t) -> %s]", ff.Name, ff.IsOn, ff.OutputNames)
 }
 
+func (ff *FlipFlop)StateSnapshot() string {
+	return ff.String()
+}
+
 func IsLineFlipFlop(line string) bool {
 	return strings.HasPrefix(line, "%")
 }
@@ -108,6 +113,9 @@ func (b *Broadcast)Outputs() []string {
 func (b *Broadcast)String() string {
 	return fmt.Sprintf("[broadcast -> %+v]", b.OutputNames)
 }
+func (b *Broadcast)StateSnapshot() string {
+	return b.String()
+}
 
 func IsLineBroadcast(line string) bool {
 	return strings.HasPrefix(line, "broadcaster")
@@ -174,6 +182,10 @@ func (c *Conjunction)String() string {
 	return fmt.Sprintf("[conjunction '%s' -> %+v]", c.Name, c.OutputNames)
 }
 
+func (c *Conjunction)StateSnapshot() string {
+	return fmt.Sprintf("[conjunction '%s' -> %+v]", c.Name, c.MostRecentPulseFromInputIsHigh)
+}
+
 func IsLineConjunction(line string) bool {
 	return strings.HasPrefix(line, "&")
 }
@@ -207,6 +219,10 @@ func (b *Button)String() string {
 	return "[button]"
 }
 
+func (b *Button)StateSnapshot() string {
+	return b.String()
+}
+
 type Output struct {}
 
 func (o *Output)Receive(s Signal) []Signal {
@@ -221,3 +237,7 @@ func (o *Output)Outputs() []string {
 func (o *Output)String() string {
 	return "[output]"
 }
+
+func (o *Output)StateSnapshot() string {
+	return o.String()
+}

day20/propagation_test.go

@@ -1,6 +1,7 @@
 package day20
 
 import (
+	"log"
 	"testing"
 )
 
@@ -41,6 +42,8 @@ func TestPropagateButtonPressExample2FourSteps(t *testing.T) {
 	t.Log("got modules:\n", modules)
 	InitStuffs(modules)
 
+	initialModulesState := ModulesState(modules)
+
 	low, high := PropagateButtonPress(modules)
 	t.Logf("got low %d and high %d\n", low, high)
 	t.Log("#1 button press:\n", modules)
@@ -56,6 +59,10 @@ func TestPropagateButtonPressExample2FourSteps(t *testing.T) {
 	if !success {
 		t.Errorf("expected low 4 got %d, high 2 got %d", low, high)
 	}
+	secondState := ModulesState(modules)
+	if initialModulesState == secondState {
+		t.Error("initial state should be different from second")
+	}
 
 	low, high = PropagateButtonPress(modules)
 	t.Logf("got low %d and high %d\n", low, high)
@@ -64,6 +71,10 @@ func TestPropagateButtonPressExample2FourSteps(t *testing.T) {
 	if !success {
 		t.Errorf("expected low 5 got %d, high 3 got %d", low, high)
 	}
+	thirdState := ModulesState(modules)
+	if initialModulesState == thirdState {
+		t.Error("initial state should be different from third")
+	}
 
 	low, high = PropagateButtonPress(modules)
 	t.Logf("got low %d and high %d\n", low, high)
@@ -73,4 +84,12 @@ func TestPropagateButtonPressExample2FourSteps(t *testing.T) {
 		t.Errorf("expected low 4 got %d, high 2 got %d", low, high)
 	}
 
+	lastState := ModulesState(modules)
+
+	log.Print("initial modules state:\n", initialModulesState)
+	log.Print("after 4 steps modules state:\n", lastState)
+	if initialModulesState != lastState {
+		t.Error("expected state to be same after 4 steps for example 2")
+	}
+
 }

day20/pulsePropagation.go

@@ -12,6 +12,7 @@ func Run() int {
 
 	filename := "day20/example2"
 	modules := ReadModules(filename)
+	InitStuffs(modules)
 	log.Print("got modules:\n", modules)
 
 	low, high := PropagateButtonPress(modules)
@@ -97,3 +98,14 @@ func InitStuffs(allModules map[string]Module) {
 	}
 
 }
+
+func ModulesState(allModules map[string]Module) string {
+	// relying on printing of map values to be ordered by key
+	// https://stackoverflow.com/a/54524991/2788805
+	states := make(map[string]string)
+	for name, module := range allModules {
+		states[name] = module.StateSnapshot()
+	}
+
+	return fmt.Sprint(states)
+}