Index: lldb.xcodeproj/project.pbxproj
===================================================================
--- lldb.xcodeproj/project.pbxproj
+++ lldb.xcodeproj/project.pbxproj
@@ -767,6 +767,7 @@
 		8C26C4261C3EA5F90031DF7C /* ThreadSanitizerRuntime.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 8C26C4241C3EA4340031DF7C /* ThreadSanitizerRuntime.cpp */; };
 		8C2D6A53197A1EAF006989C9 /* MemoryHistory.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 8C2D6A52197A1EAF006989C9 /* MemoryHistory.cpp */; };
 		8C2D6A5E197A250F006989C9 /* MemoryHistoryASan.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 8C2D6A5A197A1FDC006989C9 /* MemoryHistoryASan.cpp */; };
+		8C3BD9A01EF5D1FF0016C343 /* JSONTest.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 8C3BD99F1EF5D1B50016C343 /* JSONTest.cpp */; };
 		8C3BD9961EF45DA50016C343 /* MainThreadCheckerRuntime.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 8C3BD9951EF45D9B0016C343 /* MainThreadCheckerRuntime.cpp */; };
 		8CCB017E19BA28A80009FD44 /* ThreadCollection.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 8CCB017A19BA283D0009FD44 /* ThreadCollection.cpp */; };
 		8CCB018219BA4E270009FD44 /* SBThreadCollection.h in Headers */ = {isa = PBXBuildFile; fileRef = 8CCB018119BA4E210009FD44 /* SBThreadCollection.h */; settings = {ATTRIBUTES = (Public, ); }; };
@@ -2628,6 +2629,7 @@
 		8C2D6A54197A1EBE006989C9 /* MemoryHistory.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; name = MemoryHistory.h; path = include/lldb/Target/MemoryHistory.h; sourceTree = "<group>"; };
 		8C2D6A5A197A1FDC006989C9 /* MemoryHistoryASan.cpp */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.cpp; path = MemoryHistoryASan.cpp; sourceTree = "<group>"; };
 		8C2D6A5B197A1FDC006989C9 /* MemoryHistoryASan.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = MemoryHistoryASan.h; sourceTree = "<group>"; };
+		8C3BD99F1EF5D1B50016C343 /* JSONTest.cpp */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.cpp.cpp; path = JSONTest.cpp; sourceTree = "<group>"; };
 		8C3BD9931EF45D9B0016C343 /* MainThreadCheckerRuntime.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = MainThreadCheckerRuntime.h; sourceTree = "<group>"; };
 		8C3BD9951EF45D9B0016C343 /* MainThreadCheckerRuntime.cpp */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.cpp.cpp; path = MainThreadCheckerRuntime.cpp; sourceTree = "<group>"; };
 		8CCB017A19BA283D0009FD44 /* ThreadCollection.cpp */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.cpp; name = ThreadCollection.cpp; path = source/Target/ThreadCollection.cpp; sourceTree = "<group>"; };
@@ -3313,6 +3315,7 @@
 				23CB15041D66CD9200EDDDE1 /* Inputs */,
 				2321F9441BDD346100BA9A93 /* StringExtractorTest.cpp */,
 				2321F9451BDD346100BA9A93 /* TaskPoolTest.cpp */,
+				8C3BD99F1EF5D1B50016C343 /* JSONTest.cpp */,
 				2321F9461BDD346100BA9A93 /* UriParserTest.cpp */,
 			);
 			path = Utility;
@@ -7005,6 +7008,7 @@
 				23CB15341D66DA9300EDDDE1 /* CPlusPlusLanguageTest.cpp in Sources */,
 				AFAFD80A1E57E1B90017A14F /* ModuleCacheTest.cpp in Sources */,
 				23CB15351D66DA9300EDDDE1 /* UriParserTest.cpp in Sources */,
+				8C3BD9A01EF5D1FF0016C343 /* JSONTest.cpp in Sources */,
 				23CB15361D66DA9300EDDDE1 /* FileSpecTest.cpp in Sources */,
 				23E2E5251D90373D006F38BB /* ArchSpecTest.cpp in Sources */,
 				AF248A4D1DA71C77000B814D /* TestArm64InstEmulation.cpp in Sources */,
Index: source/Utility/JSON.cpp
===================================================================
--- source/Utility/JSON.cpp
+++ source/Utility/JSON.cpp
@@ -22,7 +22,7 @@
 using namespace lldb_private;
 
 std::string JSONString::json_string_quote_metachars(const std::string &s) {
-  if (s.find('"') == std::string::npos)
+  if (s.find_first_of("\\\n\"") == std::string::npos)
     return s;
 
   std::string output;
@@ -30,8 +30,9 @@
   const char *s_chars = s.c_str();
   for (size_t i = 0; i < s_size; i++) {
     unsigned char ch = *(s_chars + i);
-    if (ch == '"') {
+    if (ch == '"' || ch == '\\' || ch == '\n') {
       output.push_back('\\');
+      if (ch == '\n') ch = 'n';
     }
     output.push_back(ch);
   }
Index: unittests/Utility/CMakeLists.txt
===================================================================
--- unittests/Utility/CMakeLists.txt
+++ unittests/Utility/CMakeLists.txt
@@ -9,6 +9,7 @@
   TaskPoolTest.cpp
   TildeExpressionResolverTest.cpp
   TimeoutTest.cpp
+  JSONTest.cpp
   UriParserTest.cpp
   VASprintfTest.cpp
 
Index: unittests/Utility/JSONTest.cpp
===================================================================
--- unittests/Utility/JSONTest.cpp
+++ unittests/Utility/JSONTest.cpp
@@ -0,0 +1,26 @@
+#include "gtest/gtest.h"
+
+#include "lldb/Core/StreamString.h"
+#include "lldb/Utility/JSON.h"
+
+using namespace lldb_private;
+
+TEST(JSONTest, Dictionary) {
+  JSONObject o;
+  o.SetObject("key", std::make_shared<JSONString>("value"));
+
+  StreamString stream;
+  o.Write(stream);
+
+  ASSERT_EQ(stream.GetString(), R"({"key":"value"})");
+}
+
+TEST(JSONTest, Newlines) {
+  JSONObject o;
+  o.SetObject("key", std::make_shared<JSONString>("hello\nworld"));
+
+  StreamString stream;
+  o.Write(stream);
+
+  ASSERT_EQ(stream.GetString(), R"({"key":"hello\nworld"})");
+}