feat: add new helper function IsDir (#72)

file/dir.go

@@ -0,0 +1,31 @@
+package file
+
+import (
+	"os"
+)
+
+// DeleteDir deletes the directory at the given path.
+// It returns nil if the deletion succeeds, or the deletion error otherwise.
+// If the directory does not exist, DeleteDir returns nil.
+func DeleteDir(path string) error {
+	if _, err := os.Stat(path); os.IsNotExist(err) {
+		return nil
+	}
+
+	return os.Remove(path)
+}
+
+// IsDir returns whether the given path is a directory. If the path does not exist, it returns (false, nil).
+// If there is an error checking the path, it returns (false, err).
+func IsDir(path string) (bool, error) {
+	_, err := os.Stat(path)
+	if err == nil {
+		return true, nil
+	}
+
+	if os.IsNotExist(err) {
+		return false, nil
+	}
+
+	return false, err
+}

file/file.go

@@ -34,17 +34,6 @@ func ReadStringOrFile(input string) (string, bool, error) {
 	return string(result), true, nil
 }
 
-// DeleteDir deletes the directory at the given path.
-// It returns nil if the deletion succeeds, or the deletion error otherwise.
-// If the directory does not exist, DeleteDir returns nil.
-func DeleteDir(path string) error {
-	if _, err := os.Stat(path); os.IsNotExist(err) {
-		return nil
-	}
-
-	return os.Remove(path)
-}
-
 // ExpandFileList takes a list of file globs and expands them into a list
 // of matching file paths. It returns the expanded file list and any errors
 // from glob matching. This allows safely passing user input globs through to