Fix a hang

Before this change we were passing things by value and our updates to
local state never had any effect.

build.sh

@@ -28,4 +28,6 @@ fi
 go build -trimpath -ldflags="-s -w -X main.versionString=${VERSION}" -o "${BINARY}"
 
 # Alternative build line, if you want to attach to the running process in the Go debugger:
+#
+# -gcflags='-N -l' disables optimizations and inlining, which makes debugging easier.
 # go build -ldflags="-X main.versionString=${VERSION}" -gcflags='-N -l' -o "${BINARY}"

m/pagermode-search.go

@@ -27,12 +27,12 @@ type PagerModeSearch struct {
 
 	pattern   *regexp.Regexp
 	startLine linenumbers.LineNumber
-	lock      *sync.Mutex
+	lock      sync.Mutex
 
 	searcher chan searchCommand
 }
 
-func (m PagerModeSearch) drawFooter(_ string, _ string) {
+func (m *PagerModeSearch) drawFooter(_ string, _ string) {
 	width, height := m.pager.screen.Size()
 
 	pos := 0
@@ -52,7 +52,7 @@ func (m PagerModeSearch) drawFooter(_ string, _ string) {
 	}
 }
 
-func (m PagerModeSearch) searcherSearch() *linenumbers.LineNumber {
+func (m *PagerModeSearch) searcherSearch() *linenumbers.LineNumber {
 	// Search to the end
 	for position := m.startLine; ; position = position.NonWrappingAdd(1) {
 		line := m.pager.reader.GetLine(position)
@@ -78,7 +78,6 @@ func (m PagerModeSearch) searcherSearch() *linenumbers.LineNumber {
 }
 
 func (m *PagerModeSearch) initSearcher() {
-	m.lock = &sync.Mutex{}
 	m.searcher = make(chan searchCommand, 1)
 
 	go func() {
@@ -177,9 +176,12 @@ func removeLastChar(s string) string {
 	return s[:len(s)-size]
 }
 
-func (m PagerModeSearch) onKey(key twin.KeyCode) {
+func (m *PagerModeSearch) onKey(key twin.KeyCode) {
 	switch key {
 	case twin.KeyEscape, twin.KeyEnter:
+		if m.searcher != nil {
+			m.searcher <- searchCommandDone
+		}
 		//nolint:gosimple // The linter's advice is just wrong here
 		m.pager.mode = PagerModeViewing{pager: m.pager}
 
@@ -192,6 +194,9 @@ func (m PagerModeSearch) onKey(key twin.KeyCode) {
 		m.updateSearchPattern()
 
 	case twin.KeyUp, twin.KeyDown, twin.KeyPgUp, twin.KeyPgDown:
+		if m.searcher != nil {
+			m.searcher <- searchCommandDone
+		}
 		//nolint:gosimple // The linter's advice is just wrong here
 		m.pager.mode = PagerModeViewing{pager: m.pager}
 		m.pager.mode.onKey(key)
@@ -201,7 +206,7 @@ func (m PagerModeSearch) onKey(key twin.KeyCode) {
 	}
 }
 
-func (m PagerModeSearch) onRune(char rune) {
+func (m *PagerModeSearch) onRune(char rune) {
 	m.pager.searchString = m.pager.searchString + string(char)
 	m.updateSearchPattern()
 }

m/pagermode-viewing.go

@@ -144,7 +144,7 @@ func (m PagerModeViewing) onRune(char rune) {
 		p.handleScrolledDown()
 
 	case '/':
-		p.mode = PagerModeSearch{pager: p}
+		p.mode = &PagerModeSearch{pager: p}
 		p.TargetLineNumber = nil
 		p.searchString = ""
 		p.searchPattern = nil

m/search_test.go

@@ -13,7 +13,7 @@ func modeName(pager *Pager) string {
 		return "Viewing"
 	case PagerModeNotFound:
 		return "NotFound"
-	case PagerModeSearch:
+	case *PagerModeSearch:
 		return "Search"
 	case *PagerModeGotoLine:
 		return "GotoLine"
@@ -116,7 +116,7 @@ func Test152(t *testing.T) {
 
 	// Search for the first not-visible hit
 	pager.searchString = "abcde"
-	searchMode := PagerModeSearch{pager: pager}
+	searchMode := &PagerModeSearch{pager: pager}
 	pager.mode = searchMode
 
 	// Scroll to the next search hit