X-Git-Url: http://plrg.eecs.uci.edu/git/?a=blobdiff_plain;f=folly%2Ftest%2FJsonTest.cpp;h=0145fecbbcd77a6249fc3e875c625c5303fb0b06;hb=b422f6b54599ddbde6f5f596ec2fbc2171816301;hp=f6dfc354da35a86a266df1660d346c3a3a5f5e9b;hpb=43a79f74cfdeac62198fc4dbdda7a04d4d14ece6;p=folly.git

diff --git a/folly/test/JsonTest.cpp b/folly/test/JsonTest.cpp
index f6dfc354..0145fecb 100644
--- a/folly/test/JsonTest.cpp
+++ b/folly/test/JsonTest.cpp
@@ -190,6 +190,53 @@ TEST(Json, JsonEscape) {
     R"("\b\f\n\r\u0001\t\\\"/\u000b\u0007")");
 }
 
+TEST(Json, EscapeCornerCases) {
+  // The escaping logic uses some bitwise operations to determine
+  // which bytes need escaping 8 bytes at a time. Test that this logic
+  // is correct regardless of positions by planting 2 characters that
+  // may need escaping at each possible position and checking the
+  // result, for varying string lengths.
+
+  folly::json::serialization_opts opts;
+  opts.validate_utf8 = true;
+
+  std::string s;
+  std::string expected;
+  for (bool ascii : {true, false}) {
+    opts.encode_non_ascii = ascii;
+
+    for (size_t len = 2; len < 32; ++len) {
+      for (size_t i = 0; i < len; ++i) {
+        for (size_t j = 0; j < len; ++j) {
+          if (i == j) {
+            continue;
+          }
+
+          s.clear();
+          expected.clear();
+
+          expected.push_back('"');
+          for (size_t pos = 0; pos < len; ++pos) {
+            if (pos == i) {
+              s.push_back('\\');
+              expected.append("\\\\");
+            } else if (pos == j) {
+              s.append("\xe2\x82\xac");
+              expected.append(ascii ? "\\u20ac" : "\xe2\x82\xac");
+            } else {
+              s.push_back('x');
+              expected.push_back('x');
+            }
+          }
+          expected.push_back('"');
+
+          EXPECT_EQ(folly::json::serialize(s, opts), expected) << ascii;
+        }
+      }
+    }
+  }
+}
+
 TEST(Json, JsonNonAsciiEncoding) {
   folly::json::serialization_opts opts;
   opts.encode_non_ascii = true;