Jump to middle of the view when selection leaves the visible area (#2915)

docs/Config.md

@@ -35,6 +35,7 @@ gui:
   windowSize: 'normal' # one of 'normal' | 'half' | 'full' default is 'normal'
   scrollHeight: 2 # how many lines you scroll by
   scrollPastBottom: true # enable scrolling past the bottom
+  scrollOffMargin: 2 # how many lines to keep before/after the cursor when it reaches the top/bottom of the view
   sidePanelWidth: 0.3333 # number from 0 to 1
   expandFocusedSidePanel: false
   mainPanelSplitMode: 'flexible' # one of 'horizontal' | 'flexible' | 'vertical'

go.mod

@@ -15,7 +15,7 @@ require (
 	github.com/integrii/flaggy v1.4.0
 	github.com/jesseduffield/generics v0.0.0-20220320043834-727e535cbe68
 	github.com/jesseduffield/go-git/v5 v5.1.2-0.20221018185014-fdd53fef665d
-	github.com/jesseduffield/gocui v0.3.1-0.20230807090044-83a7161c8727
+	github.com/jesseduffield/gocui v0.3.1-0.20230815093813-9f3df4a6da3b
 	github.com/jesseduffield/kill v0.0.0-20220618033138-bfbe04675d10
 	github.com/jesseduffield/lazycore v0.0.0-20221012050358-03d2e40243c5
 	github.com/jesseduffield/minimal/gitignore v0.3.3-0.20211018110810-9cde264e6b1e

go.sum

@@ -179,8 +179,8 @@ github.com/jesseduffield/generics v0.0.0-20220320043834-727e535cbe68 h1:EQP2Tv8T
 github.com/jesseduffield/generics v0.0.0-20220320043834-727e535cbe68/go.mod h1:+LLj9/WUPAP8LqCchs7P+7X0R98HiFujVFANdNaxhGk=
 github.com/jesseduffield/go-git/v5 v5.1.2-0.20221018185014-fdd53fef665d h1:bO+OmbreIv91rCe8NmscRwhFSqkDJtzWCPV4Y+SQuXE=
 github.com/jesseduffield/go-git/v5 v5.1.2-0.20221018185014-fdd53fef665d/go.mod h1:nGNEErzf+NRznT+N2SWqmHnDnF9aLgANB1CUNEan09o=
-github.com/jesseduffield/gocui v0.3.1-0.20230807090044-83a7161c8727 h1:cLq698s96uDMm0n5379doAjIKoip3/8ioWIM8pySRLY=
+github.com/jesseduffield/gocui v0.3.1-0.20230815093813-9f3df4a6da3b h1:D2Qgpvo+i7bIIBbi/UtzrpyTuUj020lJeGxMa0J1jGs=
-github.com/jesseduffield/gocui v0.3.1-0.20230807090044-83a7161c8727/go.mod h1:trXE7RRGL2hTsv+Ntk+SHLtRobg9JE138n3Ug/X2Cf4=
+github.com/jesseduffield/gocui v0.3.1-0.20230815093813-9f3df4a6da3b/go.mod h1:trXE7RRGL2hTsv+Ntk+SHLtRobg9JE138n3Ug/X2Cf4=
 github.com/jesseduffield/kill v0.0.0-20220618033138-bfbe04675d10 h1:jmpr7KpX2+2GRiE91zTgfq49QvgiqB0nbmlwZ8UnOx0=
 github.com/jesseduffield/kill v0.0.0-20220618033138-bfbe04675d10/go.mod h1:aA97kHeNA+sj2Hbki0pvLslmE4CbDyhBeSSTUUnOuVo=
 github.com/jesseduffield/lazycore v0.0.0-20221012050358-03d2e40243c5 h1:CDuQmfOjAtb1Gms6a1p5L2P8RhbLUq5t8aL7PiQd2uY=

pkg/commands/patch/patch.go

@@ -149,3 +149,8 @@ func (self *Patch) LineCount() int {
 	}
 	return count
 }
+
+// Returns the number of hunks of the patch
+func (self *Patch) HunkCount() int {
+	return len(self.hunks)
+}

pkg/config/user_config.go

@@ -31,6 +31,7 @@ type GuiConfig struct {
 	BranchColors              map[string]string  `yaml:"branchColors"`
 	ScrollHeight              int                `yaml:"scrollHeight"`
 	ScrollPastBottom          bool               `yaml:"scrollPastBottom"`
+	ScrollOffMargin           int                `yaml:"scrollOffMargin"`
 	MouseEvents               bool               `yaml:"mouseEvents"`
 	SkipDiscardChangeWarning  bool               `yaml:"skipDiscardChangeWarning"`
 	SkipStashWarning          bool               `yaml:"skipStashWarning"`
@@ -418,6 +419,7 @@ func GetDefaultConfig() *UserConfig {
 		Gui: GuiConfig{
 			ScrollHeight:             2,
 			ScrollPastBottom:         true,
+			ScrollOffMargin:          2,
 			MouseEvents:              true,
 			SkipDiscardChangeWarning: false,
 			SkipStashWarning:         false,

pkg/gui/context/patch_explorer_context.go

@@ -109,8 +109,9 @@ func (self *PatchExplorerContext) FocusSelection() {
 	_, viewHeight := view.Size()
 	bufferHeight := viewHeight - 1
 	_, origin := view.Origin()
+	numLines := view.LinesHeight()
 
-	newOriginY := state.CalculateOrigin(origin, bufferHeight)
+	newOriginY := state.CalculateOrigin(origin, bufferHeight, numLines)
 
 	_ = view.SetOriginY(newOriginY)
 

pkg/gui/controllers/list_controller.go

@@ -82,6 +82,12 @@ func (self *ListController) handleLineChange(change int) error {
 	// doing this check so that if we're holding the up key at the start of the list
 	// we're not constantly re-rendering the main view.
 	if before != after {
+		if change == -1 {
+			checkScrollUp(self.context.GetViewTrait(), self.c.UserConfig.Gui.ScrollOffMargin, before, after)
+		} else if change == 1 {
+			checkScrollDown(self.context.GetViewTrait(), self.c.UserConfig.Gui.ScrollOffMargin, before, after)
+		}
+
 		return self.context.HandleFocus(types.OnFocusOpts{})
 	}
 

pkg/gui/controllers/patch_explorer_controller.go

@@ -159,13 +159,25 @@ func (self *PatchExplorerController) GetMouseKeybindings(opts types.KeybindingsO
 }
 
 func (self *PatchExplorerController) HandlePrevLine() error {
+	before := self.context.GetState().GetSelectedLineIdx()
 	self.context.GetState().CycleSelection(false)
+	after := self.context.GetState().GetSelectedLineIdx()
+
+	if self.context.GetState().SelectingLine() {
+		checkScrollUp(self.context.GetViewTrait(), self.c.UserConfig.Gui.ScrollOffMargin, before, after)
+	}
 
 	return nil
 }
 
 func (self *PatchExplorerController) HandleNextLine() error {
+	before := self.context.GetState().GetSelectedLineIdx()
 	self.context.GetState().CycleSelection(true)
+	after := self.context.GetState().GetSelectedLineIdx()
+
+	if self.context.GetState().SelectingLine() {
+		checkScrollDown(self.context.GetViewTrait(), self.c.UserConfig.Gui.ScrollOffMargin, before, after)
+	}
 
 	return nil
 }

pkg/gui/controllers/scroll_off_margin.go

@@ -0,0 +1,70 @@
+package controllers
+
+import (
+	"github.com/jesseduffield/lazygit/pkg/gui/types"
+	"github.com/jesseduffield/lazygit/pkg/utils"
+)
+
+// To be called after pressing up-arrow; checks whether the cursor entered the
+// top scroll-off margin, and so the view needs to be scrolled up one line
+func checkScrollUp(view types.IViewTrait, scrollOffMargin int, lineIdxBefore int, lineIdxAfter int) {
+	viewPortStart, viewPortHeight := view.ViewPortYBounds()
+
+	linesToScroll := calculateLinesToScrollUp(
+		viewPortStart, viewPortHeight, scrollOffMargin, lineIdxBefore, lineIdxAfter)
+	if linesToScroll != 0 {
+		view.ScrollUp(linesToScroll)
+	}
+}
+
+// To be called after pressing down-arrow; checks whether the cursor entered the
+// bottom scroll-off margin, and so the view needs to be scrolled down one line
+func checkScrollDown(view types.IViewTrait, scrollOffMargin int, lineIdxBefore int, lineIdxAfter int) {
+	viewPortStart, viewPortHeight := view.ViewPortYBounds()
+
+	linesToScroll := calculateLinesToScrollDown(
+		viewPortStart, viewPortHeight, scrollOffMargin, lineIdxBefore, lineIdxAfter)
+	if linesToScroll != 0 {
+		view.ScrollDown(linesToScroll)
+	}
+}
+
+func calculateLinesToScrollUp(viewPortStart int, viewPortHeight int, scrollOffMargin int, lineIdxBefore int, lineIdxAfter int) int {
+	// Cap the margin to half the view height. This allows setting the config to
+	// a very large value to keep the cursor always in the middle of the screen.
+	// Use +.5 so that if the height is even, the top margin is one line higher
+	// than the bottom margin.
+	scrollOffMargin = utils.Min(scrollOffMargin, int((float64(viewPortHeight)+.5)/2))
+
+	// Scroll only if the "before" position was visible (this could be false if
+	// the scroll wheel was used to scroll the selected line out of view) ...
+	if lineIdxBefore >= viewPortStart && lineIdxBefore < viewPortStart+viewPortHeight {
+		marginEnd := viewPortStart + scrollOffMargin
+		// ... and the "after" position is within the top margin (or before it)
+		if lineIdxAfter < marginEnd {
+			return marginEnd - lineIdxAfter
+		}
+	}
+
+	return 0
+}
+
+func calculateLinesToScrollDown(viewPortStart int, viewPortHeight int, scrollOffMargin int, lineIdxBefore int, lineIdxAfter int) int {
+	// Cap the margin to half the view height. This allows setting the config to
+	// a very large value to keep the cursor always in the middle of the screen.
+	// Use -.5 so that if the height is even, the bottom margin is one line lower
+	// than the top margin.
+	scrollOffMargin = utils.Min(scrollOffMargin, int((float64(viewPortHeight)-.5)/2))
+
+	// Scroll only if the "before" position was visible (this could be false if
+	// the scroll wheel was used to scroll the selected line out of view) ...
+	if lineIdxBefore >= viewPortStart && lineIdxBefore < viewPortStart+viewPortHeight {
+		marginStart := viewPortStart + viewPortHeight - scrollOffMargin - 1
+		// ... and the "after" position is within the bottom margin (or after it)
+		if lineIdxAfter > marginStart {
+			return lineIdxAfter - marginStart
+		}
+	}
+
+	return 0
+}

pkg/gui/controllers/scroll_off_margin_test.go

@@ -0,0 +1,171 @@
+package controllers
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func Test_calculateLinesToScrollUp(t *testing.T) {
+	scenarios := []struct {
+		name                  string
+		viewPortStart         int
+		viewPortHeight        int
+		scrollOffMargin       int
+		lineIdxBefore         int
+		lineIdxAfter          int
+		expectedLinesToScroll int
+	}{
+		{
+			name:                  "before position is above viewport - don't scroll",
+			viewPortStart:         10,
+			viewPortHeight:        10,
+			scrollOffMargin:       3,
+			lineIdxBefore:         9,
+			lineIdxAfter:          8,
+			expectedLinesToScroll: 0,
+		},
+		{
+			name:                  "before position is below viewport - don't scroll",
+			viewPortStart:         10,
+			viewPortHeight:        10,
+			scrollOffMargin:       3,
+			lineIdxBefore:         20,
+			lineIdxAfter:          19,
+			expectedLinesToScroll: 0,
+		},
+		{
+			name:                  "before and after positions are outside scroll-off margin - don't scroll",
+			viewPortStart:         10,
+			viewPortHeight:        10,
+			scrollOffMargin:       3,
+			lineIdxBefore:         14,
+			lineIdxAfter:          13,
+			expectedLinesToScroll: 0,
+		},
+		{
+			name:                  "before outside, after inside scroll-off margin - scroll by 1",
+			viewPortStart:         10,
+			viewPortHeight:        10,
+			scrollOffMargin:       3,
+			lineIdxBefore:         13,
+			lineIdxAfter:          12,
+			expectedLinesToScroll: 1,
+		},
+		{
+			name:                  "before inside scroll-off margin - scroll by more than 1",
+			viewPortStart:         10,
+			viewPortHeight:        10,
+			scrollOffMargin:       3,
+			lineIdxBefore:         11,
+			lineIdxAfter:          10,
+			expectedLinesToScroll: 3,
+		},
+		{
+			name:                  "very large scroll-off margin - keep view centered (even viewport height)",
+			viewPortStart:         10,
+			viewPortHeight:        10,
+			scrollOffMargin:       999,
+			lineIdxBefore:         15,
+			lineIdxAfter:          14,
+			expectedLinesToScroll: 1,
+		},
+		{
+			name:                  "very large scroll-off margin - keep view centered (odd viewport height)",
+			viewPortStart:         10,
+			viewPortHeight:        9,
+			scrollOffMargin:       999,
+			lineIdxBefore:         14,
+			lineIdxAfter:          13,
+			expectedLinesToScroll: 1,
+		},
+	}
+	for _, scenario := range scenarios {
+		t.Run(scenario.name, func(t *testing.T) {
+			linesToScroll := calculateLinesToScrollUp(scenario.viewPortStart, scenario.viewPortHeight, scenario.scrollOffMargin, scenario.lineIdxBefore, scenario.lineIdxAfter)
+			assert.Equal(t, scenario.expectedLinesToScroll, linesToScroll)
+		})
+	}
+}
+
+func Test_calculateLinesToScrollDown(t *testing.T) {
+	scenarios := []struct {
+		name                  string
+		viewPortStart         int
+		viewPortHeight        int
+		scrollOffMargin       int
+		lineIdxBefore         int
+		lineIdxAfter          int
+		expectedLinesToScroll int
+	}{
+		{
+			name:                  "before position is above viewport - don't scroll",
+			viewPortStart:         10,
+			viewPortHeight:        10,
+			scrollOffMargin:       3,
+			lineIdxBefore:         9,
+			lineIdxAfter:          10,
+			expectedLinesToScroll: 0,
+		},
+		{
+			name:                  "before position is below viewport - don't scroll",
+			viewPortStart:         10,
+			viewPortHeight:        10,
+			scrollOffMargin:       3,
+			lineIdxBefore:         20,
+			lineIdxAfter:          21,
+			expectedLinesToScroll: 0,
+		},
+		{
+			name:                  "before and after positions are outside scroll-off margin - don't scroll",
+			viewPortStart:         10,
+			viewPortHeight:        10,
+			scrollOffMargin:       3,
+			lineIdxBefore:         15,
+			lineIdxAfter:          16,
+			expectedLinesToScroll: 0,
+		},
+		{
+			name:                  "before outside, after inside scroll-off margin - scroll by 1",
+			viewPortStart:         10,
+			viewPortHeight:        10,
+			scrollOffMargin:       3,
+			lineIdxBefore:         16,
+			lineIdxAfter:          17,
+			expectedLinesToScroll: 1,
+		},
+		{
+			name:                  "before inside scroll-off margin - scroll by more than 1",
+			viewPortStart:         10,
+			viewPortHeight:        10,
+			scrollOffMargin:       3,
+			lineIdxBefore:         18,
+			lineIdxAfter:          19,
+			expectedLinesToScroll: 3,
+		},
+		{
+			name:                  "very large scroll-off margin - keep view centered (even viewport height)",
+			viewPortStart:         10,
+			viewPortHeight:        10,
+			scrollOffMargin:       999,
+			lineIdxBefore:         15,
+			lineIdxAfter:          16,
+			expectedLinesToScroll: 1,
+		},
+		{
+			name:                  "very large scroll-off margin - keep view centered (odd viewport height)",
+			viewPortStart:         10,
+			viewPortHeight:        9,
+			scrollOffMargin:       999,
+			lineIdxBefore:         14,
+			lineIdxAfter:          15,
+			expectedLinesToScroll: 1,
+		},
+	}
+	for _, scenario := range scenarios {
+		t.Run(scenario.name, func(t *testing.T) {
+			linesToScroll := calculateLinesToScrollDown(scenario.viewPortStart, scenario.viewPortHeight, scenario.scrollOffMargin, scenario.lineIdxBefore, scenario.lineIdxAfter)
+			assert.Equal(t, scenario.expectedLinesToScroll, linesToScroll)
+		})
+	}
+}

pkg/gui/patch_exploring/focus.go

@@ -2,21 +2,19 @@ package patch_exploring
 
 import "github.com/jesseduffield/lazygit/pkg/utils"
 
-func calculateOrigin(currentOrigin int, bufferHeight int, firstLineIdx int, lastLineIdx int, selectedLineIdx int, mode selectMode) int {
+func calculateOrigin(currentOrigin int, bufferHeight int, numLines int, firstLineIdx int, lastLineIdx int, selectedLineIdx int, mode selectMode) int {
 	needToSeeIdx, wantToSeeIdx := getNeedAndWantLineIdx(firstLineIdx, lastLineIdx, selectedLineIdx, mode)
 
-	return calculateNewOriginWithNeededAndWantedIdx(currentOrigin, bufferHeight, needToSeeIdx, wantToSeeIdx)
+	return calculateNewOriginWithNeededAndWantedIdx(currentOrigin, bufferHeight, numLines, needToSeeIdx, wantToSeeIdx)
 }
 
 // we want to scroll our origin so that the index we need to see is in view
 // and the other index we want to see (e.g. the other side of a line range)
-// is in as close to being in view as possible.
+// is as close to being in view as possible.
-func calculateNewOriginWithNeededAndWantedIdx(currentOrigin int, bufferHeight int, needToSeeIdx int, wantToSeeIdx int) int {
+func calculateNewOriginWithNeededAndWantedIdx(currentOrigin int, bufferHeight int, numLines int, needToSeeIdx int, wantToSeeIdx int) int {
 	origin := currentOrigin
-	if needToSeeIdx < currentOrigin {
+	if needToSeeIdx < currentOrigin || needToSeeIdx > currentOrigin+bufferHeight {
-		origin = needToSeeIdx
+		origin = utils.Max(utils.Min(needToSeeIdx-bufferHeight/2, numLines-bufferHeight-1), 0)
-	} else if needToSeeIdx > currentOrigin+bufferHeight {
-		origin = needToSeeIdx - bufferHeight
 	}
 
 	bottom := origin + bufferHeight

pkg/gui/patch_exploring/focus_test.go

@@ -11,6 +11,7 @@ func TestNewOrigin(t *testing.T) {
 		name            string
 		origin          int
 		bufferHeight    int
+		numLines        int
 		firstLineIdx    int
 		lastLineIdx     int
 		selectedLineIdx int
@@ -20,29 +21,54 @@ func TestNewOrigin(t *testing.T) {
 
 	scenarios := []scenario{
 		{
-			name:            "selection above scroll window",
+			name:            "selection above scroll window, enough room to put it in the middle",
+			origin:          250,
+			bufferHeight:    100,
+			numLines:        500,
+			firstLineIdx:    210,
+			lastLineIdx:     210,
+			selectedLineIdx: 210,
+			selectMode:      LINE,
+			expected:        160,
+		},
+		{
+			name:            "selection above scroll window, not enough room to put it in the middle",
 			origin:          50,
 			bufferHeight:    100,
+			numLines:        500,
 			firstLineIdx:    10,
 			lastLineIdx:     10,
 			selectedLineIdx: 10,
 			selectMode:      LINE,
-			expected:        10,
+			expected:        0,
 		},
 		{
-			name:            "selection below scroll window",
+			name:            "selection below scroll window, enough room to put it in the middle",
 			origin:          0,
 			bufferHeight:    100,
+			numLines:        500,
 			firstLineIdx:    150,
 			lastLineIdx:     150,
 			selectedLineIdx: 150,
 			selectMode:      LINE,
-			expected:        50,
+			expected:        100,
+		},
+		{
+			name:            "selection below scroll window, not enough room to put it in the middle",
+			origin:          0,
+			bufferHeight:    100,
+			numLines:        200,
+			firstLineIdx:    199,
+			lastLineIdx:     199,
+			selectedLineIdx: 199,
+			selectMode:      LINE,
+			expected:        99,
 		},
 		{
 			name:            "selection within scroll window",
 			origin:          0,
 			bufferHeight:    100,
+			numLines:        500,
 			firstLineIdx:    50,
 			lastLineIdx:     50,
 			selectedLineIdx: 50,
@@ -53,6 +79,7 @@ func TestNewOrigin(t *testing.T) {
 			name:            "range ending below scroll window with selection at end of range",
 			origin:          0,
 			bufferHeight:    100,
+			numLines:        500,
 			firstLineIdx:    40,
 			lastLineIdx:     150,
 			selectedLineIdx: 150,
@@ -63,6 +90,7 @@ func TestNewOrigin(t *testing.T) {
 			name:            "range ending below scroll window with selection at beginning of range",
 			origin:          0,
 			bufferHeight:    100,
+			numLines:        500,
 			firstLineIdx:    40,
 			lastLineIdx:     150,
 			selectedLineIdx: 40,
@@ -73,6 +101,7 @@ func TestNewOrigin(t *testing.T) {
 			name:            "range starting above scroll window with selection at beginning of range",
 			origin:          50,
 			bufferHeight:    100,
+			numLines:        500,
 			firstLineIdx:    40,
 			lastLineIdx:     150,
 			selectedLineIdx: 40,
@@ -83,6 +112,7 @@ func TestNewOrigin(t *testing.T) {
 			name:            "hunk extending beyond both bounds of scroll window",
 			origin:          50,
 			bufferHeight:    100,
+			numLines:        500,
 			firstLineIdx:    40,
 			lastLineIdx:     200,
 			selectedLineIdx: 70,
@@ -94,7 +124,7 @@ func TestNewOrigin(t *testing.T) {
 	for _, s := range scenarios {
 		s := s
 		t.Run(s.name, func(t *testing.T) {
-			assert.EqualValues(t, s.expected, calculateOrigin(s.origin, s.bufferHeight, s.firstLineIdx, s.lastLineIdx, s.selectedLineIdx, s.selectMode))
+			assert.EqualValues(t, s.expected, calculateOrigin(s.origin, s.bufferHeight, s.numLines, s.firstLineIdx, s.lastLineIdx, s.selectedLineIdx, s.selectMode))
 		})
 	}
 }

pkg/gui/patch_exploring/state.go

@@ -143,9 +143,14 @@ func (s *State) CycleHunk(forward bool) {
 	}
 
 	hunkIdx := s.patch.HunkContainingLine(s.selectedLineIdx)
-	start := s.patch.HunkStartIdx(hunkIdx + change)
+	if hunkIdx != -1 {
+		newHunkIdx := hunkIdx + change
+		if newHunkIdx >= 0 && newHunkIdx < s.patch.HunkCount() {
+			start := s.patch.HunkStartIdx(newHunkIdx)
 			s.selectedLineIdx = s.patch.GetNextChangeIdx(start)
 		}
+	}
+}
 
 func (s *State) CycleLine(forward bool) {
 	change := 1
@@ -216,8 +221,8 @@ func (s *State) SelectTop() {
 	s.SelectLine(0)
 }
 
-func (s *State) CalculateOrigin(currentOrigin int, bufferHeight int) int {
+func (s *State) CalculateOrigin(currentOrigin int, bufferHeight int, numLines int) int {
 	firstLineIdx, lastLineIdx := s.SelectedRange()
 
-	return calculateOrigin(currentOrigin, bufferHeight, firstLineIdx, lastLineIdx, s.GetSelectedLineIdx(), s.selectMode)
+	return calculateOrigin(currentOrigin, bufferHeight, numLines, firstLineIdx, lastLineIdx, s.GetSelectedLineIdx(), s.selectMode)
 }

vendor/github.com/jesseduffield/gocui/view.go

@@ -273,25 +273,33 @@ func (v *View) FocusPoint(cx int, cy int) {
 		ly = 0
 	}
 
-	// if line is above origin, move origin and set cursor to zero
+	v.oy = calculateNewOrigin(cy, v.oy, lineCount, ly)
-	// if line is below origin + height, move origin and set cursor to max
-	// otherwise set cursor to value - origin
-	if ly > lineCount {
-		v.cx = cx
-		v.cy = cy
-		v.oy = 0
-	} else if cy < v.oy {
-		v.cx = cx
-		v.cy = 0
-		v.oy = cy
-	} else if cy > v.oy+ly {
-		v.cx = cx
-		v.cy = ly
-		v.oy = cy - ly
-	} else {
 	v.cx = cx
 	v.cy = cy - v.oy
 }
+
+func calculateNewOrigin(selectedLine int, oldOrigin int, lineCount int, viewHeight int) int {
+	if viewHeight > lineCount {
+		return 0
+	} else if selectedLine < oldOrigin || selectedLine > oldOrigin+viewHeight {
+		// If the selected line is outside the visible area, scroll the view so
+		// that the selected line is in the middle.
+		newOrigin := selectedLine - viewHeight/2
+
+		// However, take care not to overflow if the total line count is less
+		// than the view height.
+		maxOrigin := lineCount - viewHeight - 1
+		if newOrigin > maxOrigin {
+			newOrigin = maxOrigin
+		}
+		if newOrigin < 0 {
+			newOrigin = 0
+		}
+
+		return newOrigin
+	}
+
+	return oldOrigin
 }
 
 func (s *searcher) search(str string) {

vendor/modules.txt

@@ -124,7 +124,7 @@ github.com/jesseduffield/go-git/v5/utils/merkletrie/filesystem
 github.com/jesseduffield/go-git/v5/utils/merkletrie/index
 github.com/jesseduffield/go-git/v5/utils/merkletrie/internal/frame
 github.com/jesseduffield/go-git/v5/utils/merkletrie/noder
-# github.com/jesseduffield/gocui v0.3.1-0.20230807090044-83a7161c8727
+# github.com/jesseduffield/gocui v0.3.1-0.20230815093813-9f3df4a6da3b
 ## explicit; go 1.12
 github.com/jesseduffield/gocui
 # github.com/jesseduffield/kill v0.0.0-20220618033138-bfbe04675d10