Fix race condition in HandleRender

Move SetContentLineCount into OverwriteLinesAndClearEverythingElse. Calling it
separately beforehand is not concurrency safe; we need both to happen
when the view's writeMutex is locked.

Author: stefanhaller

go.mod

@@ -18,7 +18,7 @@ require (
 	github.com/integrii/flaggy v1.4.0
 	github.com/jesseduffield/generics v0.0.0-20250517122708-b0b4a53a6f5c
 	github.com/jesseduffield/go-git/v5 v5.14.1-0.20250407170251-e1a013310ccd
-	github.com/jesseduffield/gocui v0.3.1-0.20251223143206-950739ccd44a
+	github.com/jesseduffield/gocui v0.3.1-0.20251223144240-29fe12e8d53f
 	github.com/jesseduffield/lazycore v0.0.0-20221012050358-03d2e40243c5
 	github.com/kardianos/osext v0.0.0-20190222173326-2bc1f35cddc0
 	github.com/karimkhaleel/jsonschema v0.0.0-20231001195015-d933f0d94ea3

go.sum

@@ -194,8 +194,8 @@ github.com/jesseduffield/generics v0.0.0-20250517122708-b0b4a53a6f5c h1:tC2Paiis
 github.com/jesseduffield/generics v0.0.0-20250517122708-b0b4a53a6f5c/go.mod h1:F2fEBk0ddf6ixrBrJjY7phfQ3hL9rXG0uSjvwYe50bE=
 github.com/jesseduffield/go-git/v5 v5.14.1-0.20250407170251-e1a013310ccd h1:ViKj6qth8FgcIWizn9KiACWwPemWSymx62OPN0tHT+Q=
 github.com/jesseduffield/go-git/v5 v5.14.1-0.20250407170251-e1a013310ccd/go.mod h1:lRhCiBr6XjQrvcQVa+UYsy/99d3wMXn/a0nSQlhnhlA=
-github.com/jesseduffield/gocui v0.3.1-0.20251223143206-950739ccd44a h1:XRsyqrSljes4TlaPczQViIAA4xqdnB0fKEEpZdqWWTA=
-github.com/jesseduffield/gocui v0.3.1-0.20251223143206-950739ccd44a/go.mod h1:sLIyZ2J42R6idGdtemZzsiR3xY5EF0KsvYEGh3dQv3s=
+github.com/jesseduffield/gocui v0.3.1-0.20251223144240-29fe12e8d53f h1:5ArylWehV98WTxJM7AcSa53YNskEFpHHv+VePONQn58=
+github.com/jesseduffield/gocui v0.3.1-0.20251223144240-29fe12e8d53f/go.mod h1:sLIyZ2J42R6idGdtemZzsiR3xY5EF0KsvYEGh3dQv3s=
 github.com/jesseduffield/lazycore v0.0.0-20221012050358-03d2e40243c5 h1:CDuQmfOjAtb1Gms6a1p5L2P8RhbLUq5t8aL7PiQd2uY=
 github.com/jesseduffield/lazycore v0.0.0-20221012050358-03d2e40243c5/go.mod h1:qxN4mHOAyeIDLP7IK7defgPClM/z1Kze8VVQiaEjzsQ=
 github.com/josharian/intern v1.0.0/go.mod h1:5DoeVV0s6jJacbCEi61lwdGj/aVlrQvzHFFd8Hwg//Y=

pkg/gui/context/list_context_trait.go

@@ -102,10 +102,9 @@ func (self *ListContextTrait) HandleRender() {
 		if self.getNonModelItems != nil {
 			totalLength += len(self.getNonModelItems())
 		}
-		self.GetViewTrait().SetContentLineCount(totalLength)
 		startIdx, length := self.GetViewTrait().ViewPortYBounds()
 		content := self.renderLines(startIdx, startIdx+length)
-		self.GetViewTrait().SetViewPortContentAndClearEverythingElse(content)
+		self.GetViewTrait().SetViewPortContentAndClearEverythingElse(totalLength, content)
 	} else {
 		content := self.renderLines(-1, -1)
 		self.GetViewTrait().SetContent(content)

pkg/gui/context/view_trait.go

@@ -34,13 +34,9 @@ func (self *ViewTrait) SetViewPortContent(content string) {
 	self.view.OverwriteLines(y, content)
 }
 
-func (self *ViewTrait) SetViewPortContentAndClearEverythingElse(content string) {
+func (self *ViewTrait) SetViewPortContentAndClearEverythingElse(lineCount int, content string) {
 	_, y := self.view.Origin()
-	self.view.OverwriteLinesAndClearEverythingElse(y, content)
-}
-
-func (self *ViewTrait) SetContentLineCount(lineCount int) {
-	self.view.SetContentLineCount(lineCount)
+	self.view.OverwriteLinesAndClearEverythingElse(lineCount, y, content)
 }
 
 func (self *ViewTrait) SetContent(content string) {

pkg/gui/types/context.go

@@ -205,8 +205,7 @@ type IViewTrait interface {
 	SetRangeSelectStart(yIdx int)
 	CancelRangeSelect()
 	SetViewPortContent(content string)
-	SetViewPortContentAndClearEverythingElse(content string)
-	SetContentLineCount(lineCount int)
+	SetViewPortContentAndClearEverythingElse(lineCount int, content string)
 	SetContent(content string)
 	SetFooter(value string)
 	SetOriginX(value int)

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

@@ -221,7 +221,7 @@ github.com/jesseduffield/go-git/v5/utils/merkletrie/internal/frame
 github.com/jesseduffield/go-git/v5/utils/merkletrie/noder
 github.com/jesseduffield/go-git/v5/utils/sync
 github.com/jesseduffield/go-git/v5/utils/trace
-# github.com/jesseduffield/gocui v0.3.1-0.20251223143206-950739ccd44a
+# github.com/jesseduffield/gocui v0.3.1-0.20251223144240-29fe12e8d53f
 ## explicit; go 1.12
 github.com/jesseduffield/gocui
 # github.com/jesseduffield/lazycore v0.0.0-20221012050358-03d2e40243c5