cmd/govim: extract text property removal to own func

This change extracts text property removal to it's own func.

It acts as gardening for implementing references highlights where we'll
start using another text property ID, and therefore it is added as an
internal type.

cmd/govim/highlight.go

@@ -62,19 +62,10 @@ func (v *vimstate) redefineHighlights(diags []types.Diagnostic, force bool) erro
 		return nil
 	}
 
+	v.removeTextProps(types.DiagnosticTextPropID)
+
 	v.BatchStart()
 	defer v.BatchCancelIfNotEnded()
-	for bufnr, buf := range v.buffers {
-		if !buf.Loaded {
-			continue // vim removes properties when a buffer is unloaded
-		}
-		v.BatchChannelCall("prop_remove", struct {
-			ID    int `json:"id"`
-			BufNr int `json:"bufnr"`
-			All   int `json:"all"`
-		}{0, bufnr, 1})
-	}
-
 	for _, d := range diags {
 		// Do not add textprops to unknown buffers
 		if d.Buf < 0 {
@@ -106,3 +97,22 @@ func (v *vimstate) redefineHighlights(diags []types.Diagnostic, force bool) erro
 	v.BatchEnd()
 	return nil
 }
+
+func (v *vimstate) removeTextProps(id types.TextPropID) {
+	v.BatchStart()
+	defer v.BatchCancelIfNotEnded()
+
+	for bufnr, buf := range v.buffers {
+		if !buf.Loaded {
+			continue // vim removes properties when a buffer is unloaded
+		}
+		v.BatchChannelCall("prop_remove", struct {
+			ID    int `json:"id"`
+			BufNr int `json:"bufnr"`
+			All   int `json:"all"`
+		}{int(id), bufnr, 1})
+	}
+
+	// prop_remove returns number of removed properties per call
+	v.BatchEnd()
+}

cmd/govim/internal/types/types.go

@@ -290,3 +290,10 @@ var SeverityHoverHighlight = map[Severity]config.Highlight{
 	SeverityInfo: config.HighlightHoverInfo,
 	SeverityHint: config.HighlightHoverHint,
 }
+
+// TextPropID is the govim internal mapping of ID used when adding/removing text properties
+type TextPropID int
+
+const (
+	DiagnosticTextPropID = 0
+)

cmd/govim/vimstate.go

@@ -113,18 +113,7 @@ func (v *vimstate) setConfig(args ...json.RawMessage) (interface{}, error) {
 	if !vimconfig.EqualBool(v.config.HighlightDiagnostics, preConfig.HighlightDiagnostics) {
 		if v.config.HighlightDiagnostics == nil || !*v.config.HighlightDiagnostics {
 			// HighlightDiagnostics is now not on - remove existing text properties
-			v.BatchStart()
-			for bufnr, buf := range v.buffers {
-				if !buf.Loaded {
-					continue // vim removes properties when a buffer is unloaded
-				}
-				v.BatchChannelCall("prop_remove", struct {
-					ID    int `json:"id"`
-					BufNr int `json:"bufnr"`
-					All   int `json:"all"`
-				}{0, bufnr, 1})
-			}
-			v.BatchEnd()
+			v.removeTextProps(types.DiagnosticTextPropID)
 		} else {
 			if err := v.redefineHighlights(v.diagnostics(), true); err != nil {
 				return nil, fmt.Errorf("failed to update diagnostic highlights: %v", err)