Move `escapeString` to its own file

Change-Id: Ie5c954ec73c46c9d3c679ef99a83a29cc7a08352

1 files changed, 34 insertions, 0 deletions

diff --git a/src/libutil/escape-string.hh b/src/libutil/escape-string.hh
new file mode 100644
index 000000000..28c6c8d64
--- /dev/null
+++ b/src/libutil/escape-string.hh
@@ -0,0 +1,34 @@
+#pragma once
+
+#include <limits>
+#include <ostream>
+
+namespace nix {
+
+/**
+ * Escape a string for output.
+ *
+ * With default optional parameters, the output string will round-trip through
+ * the Nix evaluator (i.e. you can copy/paste this function's output into the
+ * REPL and have it evaluate as the string that got passed in).
+ *
+ * With non-default optional parameters, the output string will be
+ * human-readable.
+ */
+
+std::ostream & escapeString(
+    std::ostream & output,
+    const std::string_view string,
+    size_t maxLength = std::numeric_limits<size_t>::max(),
+    bool ansiColors = false
+);
+
+/**
+ * Escape a string for output, writing the escaped result to a new string.
+ */
+inline std::ostream & escapeString(std::ostream & output, const char * string)
+{
+    return escapeString(output, std::string_view(string));
+}
+
+} // namespace nix