From b559cfd4c0a155112fcf3db8c060fea8204c51d8 Mon Sep 17 00:00:00 2001
From: Victor Zverovich <viz@fb.com>
Date: Thu, 19 Aug 2021 14:12:26 -0700
Subject: [PATCH] Implement basic escaping

---
 include/fmt/ranges.h | 21 ++++++++++++++++++++-
 test/ranges-test.cc  |  5 +++++
 2 files changed, 25 insertions(+), 1 deletion(-)

diff --git a/include/fmt/ranges.h b/include/fmt/ranges.h
index 317b7298..f4bbffe2 100644
--- a/include/fmt/ranges.h
+++ b/include/fmt/ranges.h
@@ -232,7 +232,26 @@ template <
     FMT_ENABLE_IF(is_std_string_like<typename std::decay<Arg>::type>::value)>
 OutputIt write_range_entry(OutputIt out, const Arg& v) {
   *out++ = '"';
-  out = write<Char>(out, v);
+  for (Char c : basic_string_view<Char>(v)) {
+    switch (c) {
+    case '\n':
+      *out++ = '\\';
+      c = 'n';
+      break;
+    case '\r':
+      *out++ = '\\';
+      c = 'r';
+      break;
+    case '\t':
+      *out++ = '\\';
+      c = 't';
+      break;
+    case '"':
+      *out++ = '\\';
+      break;
+    }
+    *out++ = c;
+  }
   *out++ = '"';
   return out;
 }
diff --git a/test/ranges-test.cc b/test/ranges-test.cc
index 4932fe21..f3fc9df1 100644
--- a/test/ranges-test.cc
+++ b/test/ranges-test.cc
@@ -262,3 +262,8 @@ TEST(ranges_test, join_range) {
   EXPECT_EQ(fmt::format("{}", fmt::join(z, ",")), "0,0,0");
 }
 #endif  // FMT_RANGES_TEST_ENABLE_JOIN
+
+TEST(ranges_test, escape_string) {
+  auto v = std::vector<std::string>{"\n\r\t\""};
+  EXPECT_EQ(fmt::format("{}", v), "[\"\\n\\r\\t\\\"\"]");
+}
\ No newline at end of file