#868 readline: display 'terminal too small error' in preview

app/app.go

@@ -16,9 +16,9 @@ const Name = "murex"
 const (
 	Major     = 6
 	Minor     = 3
-	Revision  = 4219
+	Revision  = 4221
 	Branch    = "develop"
-	BuildDate = "2024-09-18  17:08:29"
+	BuildDate = "2024-09-18  21:37:02"
 )
 
 // Copyright is the copyright owner string

builtins/docs/summaries.go

@@ -418,6 +418,7 @@ func init() {
 		"changelog/v6.0":                  "Despite this being a new major version release, it is a vary minor update. Aside from a handful of bugfixes, the most significant change is notice of deprecation for `=`, `let`, and `?`.",
 		"changelog/v6.1":                  "This release sees a massive jump in event-driven capabilities as well as several new features and bug fixes.",
 		"changelog/v6.2":                  "Bug fix release",
+		"changelog/v6.3":                  "This is a massive release ahead of the v7.0. This brings notifications of  new deprecations, new builtins, new flags, improved CI/CD flow, and changes to the website. Unfortunately it also carries 3 breaking changes.",
 	}
 
 	Synonym = map[string]string{
@@ -1070,5 +1071,6 @@ func init() {
 		"changelog/v6.0":                  "changelog/v6.0",
 		"changelog/v6.1":                  "changelog/v6.1",
 		"changelog/v6.2":                  "changelog/v6.2",
+		"changelog/v6.3":                  "changelog/v6.3",
 	}
 }

utils/readline/preview.go

@@ -107,6 +107,8 @@ func (rl *Instance) getPreviewXY() (*PreviewSizeT, error) {
 		width = 80
 	}
 
+	rl.previewAutocompleteHeight(height)
+
 	preview, forward := getPreviewWidth(width)
 	size := &PreviewSizeT{
 		Height:  height - rl.MaxTabCompleterRows - 10, // hintText, multi-line prompts, etc
@@ -117,6 +119,24 @@ func (rl *Instance) getPreviewXY() (*PreviewSizeT, error) {
 	return size, nil
 }
 
+func (rl *Instance) previewAutocompleteHeight(height int) {
+	switch {
+	case height < 40:
+		rl.MaxTabCompleterRows = noLargerThan(rl.MaxTabCompleterRows, 4)
+	case height < 30:
+		rl.MaxTabCompleterRows = noLargerThan(rl.MaxTabCompleterRows, 3)
+	case height < 20:
+		rl.MaxTabCompleterRows = noLargerThan(rl.MaxTabCompleterRows, 2)
+	}
+}
+
+func noLargerThan(src, max int) int {
+	if src > max {
+		return max
+	}
+	return src
+}
+
 func (rl *Instance) writePreviewStr() string {
 	if rl.previewMode == previewModeClosed {
 		rl.previewCache = nil
@@ -144,9 +164,9 @@ func (rl *Instance) writePreviewStr() string {
 	}
 
 	size, err := rl.getPreviewXY()
-	if err != nil || size.Height < 8 || size.Width < 10 {
+	if err != nil || size.Height < 4 || size.Width < 10 {
 		rl.previewCache = nil
-		return ""
+		return previewTerminalTooSmall
 	}
 
 	item := rl.previewItem
@@ -158,6 +178,8 @@ func (rl *Instance) writePreviewStr() string {
 	return ""
 }
 
+var previewTerminalTooSmall = fmt.Sprintf("%s%sTerminal too small to display preview%s", curPosSave, curHome, curPosRestore)
+
 const (
 	curHome       = "\x1b[H"
 	curPosSave    = "\x1b[s"

utils/readline/tab.go

@@ -71,13 +71,14 @@ func (rl *Instance) autocompleteHeightAdjust() {
 		height = 25
 	}
 
+	rl.previewAutocompleteHeight(height)
+
 	switch {
 	case height <= 4:
 		rl.MaxTabCompleterRows = 1
 	case height-4 <= rl.MaxTabCompleterRows:
 		rl.MaxTabCompleterRows = height - 4
 	}
-
 }
 
 func (rl *Instance) moveTabCompletionHighlight(x, y int) {