settings: Add glob: as prefix for file globbing maps

This gives the advantage to differentiate internal options from user defined
file globs with the same name.

internal/config/settings.go

@@ -186,11 +186,19 @@ func validateParsedSettings() error {
 					}
 				}
 			} else {
-				if _, e := glob.Compile(k); e != nil {
+				tk := strings.TrimPrefix(k, "glob:")
-					err = errors.New("Error with glob setting " + k + ": " + e.Error())
+				if _, e := glob.Compile(tk); e != nil {
+					err = errors.New("Error with glob setting " + tk + ": " + e.Error())
 					delete(parsedSettings, k)
 					continue
 				}
+				if !strings.HasPrefix(k, "glob:") {
+					// Support non-prefixed glob settings but internally convert
+					// them to prefixed ones for simplicity.
+					delete(parsedSettings, k)
+					k = "glob:" + k
+					parsedSettings[k] = v
+				}
 				for k1, v1 := range v.(map[string]any) {
 					if _, ok := defaults[k1]; ok {
 						if e := verifySetting(k1, v1, defaults[k1]); e != nil {
@@ -312,8 +320,9 @@ func InitGlobalSettings() error {
 // Must be called after ReadSettings
 func UpdatePathGlobLocals(settings map[string]any, path string) {
 	for k, v := range parsedSettings {
-		if strings.HasPrefix(reflect.TypeOf(v).String(), "map") && !strings.HasPrefix(k, "ft:") {
+		if strings.HasPrefix(reflect.TypeOf(v).String(), "map") && strings.HasPrefix(k, "glob:") {
-			g, _ := glob.Compile(k)
+			tk := strings.TrimPrefix(k, "glob:")
+			g, _ := glob.Compile(tk)
 			if g.MatchString(path) {
 				for k1, v1 := range v.(map[string]any) {
 					settings[k1] = v1

runtime/help/options.md

@@ -669,6 +669,21 @@ all files except Go files, and `tabsize` 4 for all files except Ruby files:
 
 Or similarly you can match with globs:
 
+```json
+{
+    "glob:*.go": {
+        "tabstospaces": false
+    },
+    "glob:*.rb": {
+        "tabsize": 2
+    },
+    "tabstospaces": true,
+    "tabsize": 4
+}
+```
+
+You can also omit the `glob:` prefix before globs:
+
 ```json
 {
     "*.go": {
@@ -681,3 +696,6 @@ Or similarly you can match with globs:
     "tabsize": 4
 }
 ```
+
+But it is generally more recommended to use the `glob:` prefix, as it avoids
+potential conflicts with option names.