fix: incorrect value returned by Duration()

pipad.Duration(), pikey.Duration(), pimouse.Duration() reports "1" when input was pressed in the last frame and released in the current one. It should return 0 in such case.

Author: elgopher

internal/input/input.go

@@ -13,12 +13,12 @@ func (s *State[T]) Duration(input T) int {
 	return s.pressedInput(input).duration()
 }
 
-func (s *State[T]) SetStartFrame(input T, frame int) {
-	s.pressedInput(input).startFrame = frame
+func (s *State[T]) SetDownFrame(input T, frame int) {
+	s.pressedInput(input).downFrame = frame
 }
 
-func (s *State[T]) SetStopFrame(input T, frame int) {
-	s.pressedInput(input).stopFrame = frame
+func (s *State[T]) SetUpFrame(input T, frame int) {
+	s.pressedInput(input).upFrame = frame
 }
 
 func (s *State[T]) pressedInput(input T) *pressedInput {
@@ -27,24 +27,24 @@ func (s *State[T]) pressedInput(input T) *pressedInput {
 	}
 	p, ok := s.pressedInputs[input]
 	if !ok {
-		p = &pressedInput{startFrame: -1, stopFrame: -1}
+		p = &pressedInput{downFrame: -1, upFrame: -1}
 		s.pressedInputs[input] = p
 	}
 	return p
 }
 
 type pressedInput struct {
-	startFrame, stopFrame int
+	downFrame, upFrame int
 }
 
 func (p pressedInput) duration() int {
-	if p.startFrame < 0 {
+	if p.downFrame < 0 {
 		return 0
 	}
-	if p.startFrame > p.stopFrame {
-		return pi.Frame - p.startFrame + 1
+	if p.downFrame > p.upFrame {
+		return pi.Frame - p.downFrame + 1
 	}
-	if p.stopFrame == pi.Frame {
+	if p.downFrame == p.upFrame && p.upFrame == pi.Frame {
 		return 1
 	}
 	return 0

internal/input/input_test.go

@@ -0,0 +1,64 @@
+// Copyright 2025 Jacek Olszak
+// This code is licensed under MIT license (see LICENSE for details)
+
+package input_test
+
+import (
+	"github.com/elgopher/pi"
+	"github.com/elgopher/pi/internal/input"
+	"github.com/stretchr/testify/assert"
+	"testing"
+)
+
+func TestState_Duration(t *testing.T) {
+	const btn = "btn"
+
+	t.Run("should return 0 when input was never pressed", func(t *testing.T) {
+		var i input.State[string]
+		assert.Equal(t, 0, i.Duration(btn))
+	})
+
+	t.Run("should return 1 when input was pressed and released this frame", func(t *testing.T) {
+		var i input.State[string]
+		pi.Frame = 1
+		i.SetDownFrame(btn, pi.Frame)
+		i.SetUpFrame(btn, pi.Frame)
+		assert.Equal(t, 1, i.Duration(btn))
+	})
+
+	t.Run("should return 0 when input was pressed previous frame and released this frame", func(t *testing.T) {
+		var i input.State[string]
+		pi.Frame = 0
+		i.SetDownFrame(btn, pi.Frame)
+		pi.Frame++
+		i.SetUpFrame(btn, pi.Frame)
+		assert.Equal(t, 0, i.Duration(btn))
+	})
+
+	t.Run("should return 2 when input was pressed previous frame but not released this frame", func(t *testing.T) {
+		var i input.State[string]
+		pi.Frame = 0
+		i.SetDownFrame(btn, pi.Frame)
+		pi.Frame++
+		assert.Equal(t, 2, i.Duration(btn))
+	})
+
+	t.Run("should return 1 when input was pressed, released and pressed again this frame", func(t *testing.T) {
+		var i input.State[string]
+		pi.Frame = 0
+		i.SetDownFrame(btn, pi.Frame)
+		i.SetUpFrame(btn, pi.Frame)
+		i.SetDownFrame(btn, pi.Frame)
+		assert.Equal(t, 1, i.Duration(btn))
+	})
+
+	t.Run("should return 1 when input was pressed and released previous frame and pressed this frame", func(t *testing.T) {
+		var i input.State[string]
+		pi.Frame = 0
+		i.SetDownFrame(btn, pi.Frame)
+		i.SetUpFrame(btn, pi.Frame)
+		pi.Frame++
+		i.SetDownFrame(btn, pi.Frame)
+		assert.Equal(t, 1, i.Duration(btn))
+	})
+}

pikey/pikey.go

@@ -125,9 +125,9 @@ func init() {
 	onKey := func(event Event, _ pievent.Handler) {
 		switch event.Type {
 		case EventDown:
-			keyState.SetStartFrame(event.Key, pi.Frame)
+			keyState.SetDownFrame(event.Key, pi.Frame)
 		case EventUp:
-			keyState.SetStopFrame(event.Key, pi.Frame)
+			keyState.SetUpFrame(event.Key, pi.Frame)
 		}
 	}
 	Target().SubscribeAll(onKey)

pimouse/pimouse.go

@@ -36,9 +36,9 @@ func init() {
 	onButton := func(event EventButton, _ pievent.Handler) {
 		switch event.Type {
 		case EventButtonDown:
-			buttonState.SetStartFrame(event.Button, pi.Frame)
+			buttonState.SetDownFrame(event.Button, pi.Frame)
 		case EventButtonUp:
-			buttonState.SetStopFrame(event.Button, pi.Frame)
+			buttonState.SetUpFrame(event.Button, pi.Frame)
 		}
 	}
 	buttonTarget.SubscribeAll(onButton)

pipad/pipad.go

@@ -116,11 +116,11 @@ func onButton(event EventButton, _ pievent.Handler) {
 
 	switch event.Type {
 	case EventDown:
-		buttonState[event.Player].SetStartFrame(event.Button, pi.Frame)
-		buttonAnyState.SetStartFrame(event.Button, pi.Frame)
+		buttonState[event.Player].SetDownFrame(event.Button, pi.Frame)
+		buttonAnyState.SetDownFrame(event.Button, pi.Frame)
 	case EventUp:
-		buttonState[event.Player].SetStopFrame(event.Button, pi.Frame)
-		buttonAnyState.SetStopFrame(event.Button, pi.Frame)
+		buttonState[event.Player].SetUpFrame(event.Button, pi.Frame)
+		buttonAnyState.SetUpFrame(event.Button, pi.Frame)
 	}
 }