feat: add file helper functions (#55)

file/file.go

@@ -0,0 +1,39 @@
+package file
+
+import "os"
+
+// The MSDN docs appear to say that a normal path that is 248 bytes long will work;
+// empirically the path must be less then 248 bytes long.
+// See https://learn.microsoft.com/en-us/windows/win32/fileio/naming-a-file#maximum-path-length-limitation
+const maxPathLenght = 248
+
+// ReadStringOrFile returns the content of a string or a file if the file exists.
+// The returned boolean value indicates whether the specified `input` was a file path or not.
+func ReadStringOrFile(input string) (string, bool, error) {
+	if len(input) >= maxPathLenght {
+		return input, false, nil
+	}
+
+	// Check if input is a file path
+	if _, err := os.Stat(input); err != nil && os.IsNotExist(err) {
+		// No file found => use input as result
+		return input, false, nil
+	} else if err != nil {
+		return "", false, err
+	}
+
+	result, err := os.ReadFile(input)
+	if err != nil {
+		return "", true, err
+	}
+
+	return string(result), true, nil
+}
+
+func DeleteDir(path string) error {
+	if _, err := os.Stat(path); os.IsNotExist(err) {
+		return nil
+	}
+
+	return os.Remove(path)
+}