Memoize the glob statement

Because we were doing the same work many times :(

utils/modifycommand.go

@@ -62,6 +62,7 @@ func (c *ModifyCommand) Validate() error {
 
 // Ehh.. Not much better... Guess this wasn't the big deal
 var matchesMemoTable map[string]bool = make(map[string]bool)
+var globMemoTable map[string][]string = make(map[string][]string)
 
 func Matches(path string, glob string) (bool, error) {
 	matchesLogger := modifyCommandLogger.WithPrefix("Matches").WithField("path", path).WithField("glob", glob)
@@ -225,10 +226,16 @@ func ExpandGlobs(patterns map[string]struct{}) ([]string, error) {
 	for pattern := range patterns {
 		expandGlobsLogger.Debug("Processing glob pattern: %q", pattern)
 		static, pattern := SplitPattern(pattern)
-		matches, err := doublestar.Glob(os.DirFS(static), pattern)
-		if err != nil {
-			expandGlobsLogger.Warning("Error expanding glob %q in %q: %v", pattern, static, err)
-			continue
+		key := static + "|" + pattern
+		matches, ok := globMemoTable[key]
+		if !ok {
+			var err error
+			matches, err = doublestar.Glob(os.DirFS(static), pattern)
+			if err != nil {
+				expandGlobsLogger.Warning("Error expanding glob %q in %q: %v", pattern, static, err)
+				continue
+			}
+			globMemoTable[key] = matches
 		}
 		expandGlobsLogger.Debug("Found %d matches for pattern %q", len(matches), pattern)
 		expandGlobsLogger.Trace("Raw matches for pattern %q: %v", pattern, matches)