unittests/Support/JSONTest.cpp - llvm - Git at Google

 //===-- JSONTest.cpp - JSON unit tests --------------------------*- C++ -*-===//
 //
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//

 #include "llvm/Support/JSON.h"

 #include "gmock/gmock.h"
 #include "gtest/gtest.h"

 namespace llvm {
 namespace json {

 namespace {

 std::string s(const Value &E) { return llvm::formatv("{0}", E).str(); }
 std::string sp(const Value &E) { return llvm::formatv("{0:2}", E).str(); }

 TEST(JSONTest, Types) {
   EXPECT_EQ("true", s(true));
   EXPECT_EQ("null", s(nullptr));
   EXPECT_EQ("2.5", s(2.5));
   EXPECT_EQ(R"("foo")", s("foo"));
   EXPECT_EQ("[1,2,3]", s({1, 2, 3}));
   EXPECT_EQ(R"({"x":10,"y":20})", s(Object{{"x", 10}, {"y", 20}}));

 #ifdef NDEBUG
   EXPECT_EQ(R"("��")", s("\xC0\x80"));
   EXPECT_EQ(R"({"��":0})", s(Object{{"\xC0\x80", 0}}));
 #else
   EXPECT_DEATH(s("\xC0\x80"), "Invalid UTF-8");
   EXPECT_DEATH(s(Object{{"\xC0\x80", 0}}), "Invalid UTF-8");
 #endif
 }

 TEST(JSONTest, Constructors) {
   // Lots of edge cases around empty and singleton init lists.
   EXPECT_EQ("[[[3]]]", s({{{3}}}));
   EXPECT_EQ("[[[]]]", s({{{}}}));
   EXPECT_EQ("[[{}]]", s({{Object{}}}));
   EXPECT_EQ(R"({"A":{"B":{}}})", s(Object{{"A", Object{{"B", Object{}}}}}));
   EXPECT_EQ(R"({"A":{"B":{"X":"Y"}}})",
             s(Object{{"A", Object{{"B", Object{{"X", "Y"}}}}}}));
   EXPECT_EQ("null", s(llvm::Optional<double>()));
   EXPECT_EQ("2.5", s(llvm::Optional<double>(2.5)));
   EXPECT_EQ("[[2.5,null]]", s(std::vector<std::vector<llvm::Optional<double>>>{
                                  {2.5, llvm::None}}));
 }

 TEST(JSONTest, StringOwnership) {
   char X[] = "Hello";
   Value Alias = static_cast<const char *>(X);
   X[1] = 'a';
   EXPECT_EQ(R"("Hallo")", s(Alias));

   std::string Y = "Hello";
   Value Copy = Y;
   Y[1] = 'a';
   EXPECT_EQ(R"("Hello")", s(Copy));
 }

 TEST(JSONTest, CanonicalOutput) {
   // Objects are sorted (but arrays aren't)!
   EXPECT_EQ(R"({"a":1,"b":2,"c":3})", s(Object{{"a", 1}, {"c", 3}, {"b", 2}}));
   EXPECT_EQ(R"(["a","c","b"])", s({"a", "c", "b"}));
   EXPECT_EQ("3", s(3.0));
 }

 TEST(JSONTest, Escaping) {
   std::string test = {
       0,                    // Strings may contain nulls.
       '\b',   '\f',         // Have mnemonics, but we escape numerically.
       '\r',   '\n',   '\t', // Escaped with mnemonics.
       'S',    '\"',   '\\', // Printable ASCII characters.
       '\x7f',               // Delete is not escaped.
       '\xce', '\x94',       // Non-ASCII UTF-8 is not escaped.
   };

   std::string teststring = R"("\u0000\u0008\u000c\r\n\tS\"\\)"
                            "\x7f\xCE\x94\"";

   EXPECT_EQ(teststring, s(test));

   EXPECT_EQ(R"({"object keys are\nescaped":true})",
             s(Object{{"object keys are\nescaped", true}}));
 }

 TEST(JSONTest, PrettyPrinting) {
   const char str[] = R"({
   "empty_array": [],
   "empty_object": {},
   "full_array": [
     1,
     null
   ],
   "full_object": {
     "nested_array": [
       {
         "property": "value"
       }
     ]
   }
 })";

   EXPECT_EQ(str, sp(Object{
                      {"empty_object", Object{}},
                      {"empty_array", {}},
                      {"full_array", {1, nullptr}},
                      {"full_object",
                       Object{
                           {"nested_array",
                            {Object{
                                {"property", "value"},
                            }}},
                       }},
                  }));
 }

 TEST(JSONTest, Parse) {
   auto Compare = [](llvm::StringRef S, Value Expected) {
     if (auto E = parse(S)) {
       // Compare both string forms and with operator==, in case we have bugs.
       EXPECT_EQ(*E, Expected);
       EXPECT_EQ(sp(*E), sp(Expected));
     } else {
       handleAllErrors(E.takeError(), [S](const llvm::ErrorInfoBase &E) {
         FAIL() << "Failed to parse JSON >>> " << S << " <<<: " << E.message();
       });
     }
   };

   Compare(R"(true)", true);
   Compare(R"(false)", false);
   Compare(R"(null)", nullptr);

   Compare(R"(42)", 42);
   Compare(R"(2.5)", 2.5);
   Compare(R"(2e50)", 2e50);
   Compare(R"(1.2e3456789)", std::numeric_limits<double>::infinity());

   Compare(R"("foo")", "foo");
   Compare(R"("\"\\\b\f\n\r\t")", "\"\\\b\f\n\r\t");
   Compare(R"("\u0000")", llvm::StringRef("\0", 1));
   Compare("\"\x7f\"", "\x7f");
   Compare(R"("\ud801\udc37")", u8"\U00010437"); // UTF16 surrogate pair escape.
   Compare("\"\xE2\x82\xAC\xF0\x9D\x84\x9E\"", u8"\u20ac\U0001d11e"); // UTF8
   Compare(
       R"("LoneLeading=\ud801, LoneTrailing=\udc01, LeadingLeadingTrailing=\ud801\ud801\udc37")",
       u8"LoneLeading=\ufffd, LoneTrailing=\ufffd, "
       u8"LeadingLeadingTrailing=\ufffd\U00010437"); // Invalid unicode.

   Compare(R"({"":0,"":0})", Object{{"", 0}});
   Compare(R"({"obj":{},"arr":[]})", Object{{"obj", Object{}}, {"arr", {}}});
   Compare(R"({"\n":{"\u0000":[[[[]]]]}})",
           Object{{"\n", Object{
                             {llvm::StringRef("\0", 1), {{{{}}}}},
                         }}});
   Compare("\r[\n\t] ", {});
 }

 TEST(JSONTest, ParseErrors) {
   auto ExpectErr = [](llvm::StringRef Msg, llvm::StringRef S) {
     if (auto E = parse(S)) {
       // Compare both string forms and with operator==, in case we have bugs.
       FAIL() << "Parsed JSON >>> " << S << " <<< but wanted error: " << Msg;
     } else {
       handleAllErrors(E.takeError(), [S, Msg](const llvm::ErrorInfoBase &E) {
         EXPECT_THAT(E.message(), testing::HasSubstr(Msg)) << S;
       });
     }
   };
   ExpectErr("Unexpected EOF", "");
   ExpectErr("Unexpected EOF", "[");
   ExpectErr("Text after end of document", "[][]");
   ExpectErr("Invalid JSON value (false?)", "fuzzy");
   ExpectErr("Expected , or ]", "[2?]");
   ExpectErr("Expected object key", "{a:2}");
   ExpectErr("Expected : after object key", R"({"a",2})");
   ExpectErr("Expected , or } after object property", R"({"a":2 "b":3})");
   ExpectErr("Invalid JSON value", R"([&%!])");
   ExpectErr("Invalid JSON value (number?)", "1e1.0");
   ExpectErr("Unterminated string", R"("abc\"def)");
   ExpectErr("Control character in string", "\"abc\ndef\"");
   ExpectErr("Invalid escape sequence", R"("\030")");
   ExpectErr("Invalid \\u escape sequence", R"("\usuck")");
   ExpectErr("[3:3, byte=19]", R"({
   "valid": 1,
   invalid: 2
 })");
   ExpectErr("Invalid UTF-8 sequence", "\"\xC0\x80\""); // WTF-8 null
 }

 // Direct tests of isUTF8 and fixUTF8. Internal uses are also tested elsewhere.
 TEST(JSONTest, UTF8) {
   for (const char *Valid : {
            "this is ASCII text",
            "thïs tëxt häs BMP chäräctërs",
            "𐌶𐌰L𐌾𐍈 C𐍈𐌼𐌴𐍃",
        }) {
     EXPECT_TRUE(isUTF8(Valid)) << Valid;
     EXPECT_EQ(fixUTF8(Valid), Valid);
   }
   for (auto Invalid : std::vector<std::pair<const char *, const char *>>{
            {"lone trailing \x81\x82 bytes", "lone trailing �� bytes"},
            {"missing trailing \xD0 bytes", "missing trailing � bytes"},
            {"truncated character \xD0", "truncated character �"},
            {"not \xC1\x80 the \xE0\x9f\xBF shortest \xF0\x83\x83\x83 encoding",
             "not �� the ��� shortest ���� encoding"},
            {"too \xF9\x80\x80\x80\x80 long", "too ����� long"},
            {"surrogate \xED\xA0\x80 invalid \xF4\x90\x80\x80",
             "surrogate ��� invalid ����"}}) {
     EXPECT_FALSE(isUTF8(Invalid.first)) << Invalid.first;
     EXPECT_EQ(fixUTF8(Invalid.first), Invalid.second);
   }
 }

 TEST(JSONTest, Inspection) {
   llvm::Expected<Value> Doc = parse(R"(
     {
       "null": null,
       "boolean": false,
       "number": 2.78,
       "string": "json",
       "array": [null, true, 3.14, "hello", [1,2,3], {"time": "arrow"}],
       "object": {"fruit": "banana"}
     }
   )");
   EXPECT_TRUE(!!Doc);

   Object *O = Doc->getAsObject();
   ASSERT_TRUE(O);

   EXPECT_FALSE(O->getNull("missing"));
   EXPECT_FALSE(O->getNull("boolean"));
   EXPECT_TRUE(O->getNull("null"));

   EXPECT_EQ(O->getNumber("number"), llvm::Optional<double>(2.78));
   EXPECT_FALSE(O->getInteger("number"));
   EXPECT_EQ(O->getString("string"), llvm::Optional<llvm::StringRef>("json"));
   ASSERT_FALSE(O->getObject("missing"));
   ASSERT_FALSE(O->getObject("array"));
   ASSERT_TRUE(O->getObject("object"));
   EXPECT_EQ(*O->getObject("object"), (Object{{"fruit", "banana"}}));

   Array *A = O->getArray("array");
   ASSERT_TRUE(A);
   EXPECT_EQ((*A)[1].getAsBoolean(), llvm::Optional<bool>(true));
   ASSERT_TRUE((*A)[4].getAsArray());
   EXPECT_EQ(*(*A)[4].getAsArray(), (Array{1, 2, 3}));
   EXPECT_EQ((*(*A)[4].getAsArray())[1].getAsInteger(),
             llvm::Optional<int64_t>(2));
   int I = 0;
   for (Value &E : *A) {
     if (I++ == 5) {
       ASSERT_TRUE(E.getAsObject());
       EXPECT_EQ(E.getAsObject()->getString("time"),
                 llvm::Optional<llvm::StringRef>("arrow"));
     } else
       EXPECT_FALSE(E.getAsObject());
   }
 }

 // Verify special integer handling - we try to preserve exact int64 values.
 TEST(JSONTest, Integers) {
   struct {
     const char *Desc;
     Value Val;
     const char *Str;
     llvm::Optional<int64_t> AsInt;
     llvm::Optional<double> AsNumber;
   } TestCases[] = {
       {
           "Non-integer. Stored as double, not convertible.",
           double{1.5},
           "1.5",
           llvm::None,
           1.5,
       },

       {
           "Integer, not exact double. Stored as int64, convertible.",
           int64_t{0x4000000000000001},
           "4611686018427387905",
           int64_t{0x4000000000000001},
           double{0x4000000000000000},
       },

       {
           "Negative integer, not exact double. Stored as int64, convertible.",
           int64_t{-0x4000000000000001},
           "-4611686018427387905",
           int64_t{-0x4000000000000001},
           double{-0x4000000000000000},
       },

       {
           "Dynamically exact integer. Stored as double, convertible.",
           double{0x6000000000000000},
           "6.9175290276410819e+18",
           int64_t{0x6000000000000000},
           double{0x6000000000000000},
       },

       {
           "Dynamically integer, >64 bits. Stored as double, not convertible.",
           1.5 * double{0x8000000000000000},
           "1.3835058055282164e+19",
           llvm::None,
           1.5 * double{0x8000000000000000},
       },
   };
   for (const auto &T : TestCases) {
     EXPECT_EQ(T.Str, s(T.Val)) << T.Desc;
     llvm::Expected<Value> Doc = parse(T.Str);
     EXPECT_TRUE(!!Doc) << T.Desc;
     EXPECT_EQ(Doc->getAsInteger(), T.AsInt) << T.Desc;
     EXPECT_EQ(Doc->getAsNumber(), T.AsNumber) << T.Desc;
     EXPECT_EQ(T.Val, *Doc) << T.Desc;
     EXPECT_EQ(T.Str, s(*Doc)) << T.Desc;
   }
 }

 // Sample struct with typical JSON-mapping rules.
 struct CustomStruct {
   CustomStruct() : B(false) {}
   CustomStruct(std::string S, llvm::Optional<int> I, bool B)
       : S(S), I(I), B(B) {}
   std::string S;
   llvm::Optional<int> I;
   bool B;
 };
 inline bool operator==(const CustomStruct &L, const CustomStruct &R) {
   return L.S == R.S && L.I == R.I && L.B == R.B;
 }
 inline llvm::raw_ostream &operator<<(llvm::raw_ostream &OS,
                                      const CustomStruct &S) {
   return OS << "(" << S.S << ", " << (S.I ? std::to_string(*S.I) : "None")
             << ", " << S.B << ")";
 }
 bool fromJSON(const Value &E, CustomStruct &R) {
   ObjectMapper O(E);
   if (!O || !O.map("str", R.S) || !O.map("int", R.I))
     return false;
   O.map("bool", R.B);
   return true;
 }

 TEST(JSONTest, Deserialize) {
   std::map<std::string, std::vector<CustomStruct>> R;
   CustomStruct ExpectedStruct = {"foo", 42, true};
   std::map<std::string, std::vector<CustomStruct>> Expected;
   Value J = Object{
       {"foo",
        Array{
            Object{
                {"str", "foo"},
                {"int", 42},
                {"bool", true},
                {"unknown", "ignored"},
            },
            Object{{"str", "bar"}},
            Object{
                {"str", "baz"}, {"bool", "string"}, // OK, deserialize ignores.
            },
        }}};
   Expected["foo"] = {
       CustomStruct("foo", 42, true),
       CustomStruct("bar", llvm::None, false),
       CustomStruct("baz", llvm::None, false),
   };
   ASSERT_TRUE(fromJSON(J, R));
   EXPECT_EQ(R, Expected);

   CustomStruct V;
   EXPECT_FALSE(fromJSON(nullptr, V)) << "Not an object " << V;
   EXPECT_FALSE(fromJSON(Object{}, V)) << "Missing required field " << V;
   EXPECT_FALSE(fromJSON(Object{{"str", 1}}, V)) << "Wrong type " << V;
   // Optional<T> must parse as the correct type if present.
   EXPECT_FALSE(fromJSON(Object{{"str", 1}, {"int", "string"}}, V))
       << "Wrong type for Optional<T> " << V;
 }

 } // namespace
 } // namespace json
 } // namespace llvm
	//===-- JSONTest.cpp - JSON unit tests --------------------------- C++ --===//
	//
	// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
	// See https://llvm.org/LICENSE.txt for license information.
	// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
	//
	//===----------------------------------------------------------------------===//

	#include "llvm/Support/JSON.h"

	#include "gmock/gmock.h"
	#include "gtest/gtest.h"

	namespace llvm {
	namespace json {

	namespace {

	std::string s(const Value &E) { return llvm::formatv("{0}", E).str(); }
	std::string sp(const Value &E) { return llvm::formatv("{0:2}", E).str(); }

	TEST(JSONTest, Types) {
	EXPECT_EQ("true", s(true));
	EXPECT_EQ("null", s(nullptr));
	EXPECT_EQ("2.5", s(2.5));
	EXPECT_EQ(R"("foo")", s("foo"));
	EXPECT_EQ("[1,2,3]", s({1, 2, 3}));
	EXPECT_EQ(R"({"x":10,"y":20})", s(Object{{"x", 10}, {"y", 20}}));

	#ifdef NDEBUG
	EXPECT_EQ(R"("��")", s("\xC0\x80"));
	EXPECT_EQ(R"({"��":0})", s(Object{{"\xC0\x80", 0}}));
	#else
	EXPECT_DEATH(s("\xC0\x80"), "Invalid UTF-8");
	EXPECT_DEATH(s(Object{{"\xC0\x80", 0}}), "Invalid UTF-8");
	#endif
	}

	TEST(JSONTest, Constructors) {
	// Lots of edge cases around empty and singleton init lists.
	EXPECT_EQ("[[[3]]]", s({{{3}}}));
	EXPECT_EQ("[[[]]]", s({{{}}}));
	EXPECT_EQ("[[{}]]", s({{Object{}}}));
	EXPECT_EQ(R"({"A":{"B":{}}})", s(Object{{"A", Object{{"B", Object{}}}}}));
	EXPECT_EQ(R"({"A":{"B":{"X":"Y"}}})",
	s(Object{{"A", Object{{"B", Object{{"X", "Y"}}}}}}));
	EXPECT_EQ("null", s(llvm::Optional<double>()));
	EXPECT_EQ("2.5", s(llvm::Optional<double>(2.5)));
	EXPECT_EQ("[[2.5,null]]", s(std::vector<std::vector<llvm::Optional<double>>>{
	{2.5, llvm::None}}));
	}

	TEST(JSONTest, StringOwnership) {
	char X[] = "Hello";
	Value Alias = static_cast<const char *>(X);
	X[1] = 'a';
	EXPECT_EQ(R"("Hallo")", s(Alias));

	std::string Y = "Hello";
	Value Copy = Y;
	Y[1] = 'a';
	EXPECT_EQ(R"("Hello")", s(Copy));
	}

	TEST(JSONTest, CanonicalOutput) {
	// Objects are sorted (but arrays aren't)!
	EXPECT_EQ(R"({"a":1,"b":2,"c":3})", s(Object{{"a", 1}, {"c", 3}, {"b", 2}}));
	EXPECT_EQ(R"(["a","c","b"])", s({"a", "c", "b"}));
	EXPECT_EQ("3", s(3.0));
	}

	TEST(JSONTest, Escaping) {
	std::string test = {
	0, // Strings may contain nulls.
	'\b', '\f', // Have mnemonics, but we escape numerically.
	'\r', '\n', '\t', // Escaped with mnemonics.
	'S', '\"', '\\', // Printable ASCII characters.
	'\x7f', // Delete is not escaped.
	'\xce', '\x94', // Non-ASCII UTF-8 is not escaped.
	};

	std::string teststring = R"("\u0000\u0008\u000c\r\n\tS\"\\)"
	"\x7f\xCE\x94\"";

	EXPECT_EQ(teststring, s(test));

	EXPECT_EQ(R"({"object keys are\nescaped":true})",
	s(Object{{"object keys are\nescaped", true}}));
	}

	TEST(JSONTest, PrettyPrinting) {
	const char str[] = R"({
	"empty_array": [],
	"empty_object": {},
	"full_array": [
	1,
	null
	],
	"full_object": {
	"nested_array": [
	{
	"property": "value"
	}
	]
	}
	})";

	EXPECT_EQ(str, sp(Object{
	{"empty_object", Object{}},
	{"empty_array", {}},
	{"full_array", {1, nullptr}},
	{"full_object",
	Object{
	{"nested_array",
	{Object{
	{"property", "value"},
	}}},
	}},
	}));
	}

	TEST(JSONTest, Parse) {
	auto Compare = [](llvm::StringRef S, Value Expected) {
	if (auto E = parse(S)) {
	// Compare both string forms and with operator==, in case we have bugs.
	EXPECT_EQ(*E, Expected);
	EXPECT_EQ(sp(*E), sp(Expected));
	} else {
	handleAllErrors(E.takeError(), [S](const llvm::ErrorInfoBase &E) {
	FAIL() << "Failed to parse JSON >>> " << S << " <<<: " << E.message();
	});
	}
	};

	Compare(R"(true)", true);
	Compare(R"(false)", false);
	Compare(R"(null)", nullptr);

	Compare(R"(42)", 42);
	Compare(R"(2.5)", 2.5);
	Compare(R"(2e50)", 2e50);
	Compare(R"(1.2e3456789)", std::numeric_limits<double>::infinity());

	Compare(R"("foo")", "foo");
	Compare(R"("\"\\\b\f\n\r\t")", "\"\\\b\f\n\r\t");
	Compare(R"("\u0000")", llvm::StringRef("\0", 1));
	Compare("\"\x7f\"", "\x7f");
	Compare(R"("\ud801\udc37")", u8"\U00010437"); // UTF16 surrogate pair escape.
	Compare("\"\xE2\x82\xAC\xF0\x9D\x84\x9E\"", u8"\u20ac\U0001d11e"); // UTF8
	Compare(
	R"("LoneLeading=\ud801, LoneTrailing=\udc01, LeadingLeadingTrailing=\ud801\ud801\udc37")",
	u8"LoneLeading=\ufffd, LoneTrailing=\ufffd, "
	u8"LeadingLeadingTrailing=\ufffd\U00010437"); // Invalid unicode.

	Compare(R"({"":0,"":0})", Object{{"", 0}});
	Compare(R"({"obj":{},"arr":[]})", Object{{"obj", Object{}}, {"arr", {}}});
	Compare(R"({"\n":{"\u0000":[[[[]]]]}})",
	Object{{"\n", Object{
	{llvm::StringRef("\0", 1), {{{{}}}}},
	}}});
	Compare("\r[\n\t] ", {});
	}

	TEST(JSONTest, ParseErrors) {
	auto ExpectErr = [](llvm::StringRef Msg, llvm::StringRef S) {
	if (auto E = parse(S)) {
	// Compare both string forms and with operator==, in case we have bugs.
	FAIL() << "Parsed JSON >>> " << S << " <<< but wanted error: " << Msg;
	} else {
	handleAllErrors(E.takeError(), [S, Msg](const llvm::ErrorInfoBase &E) {
	EXPECT_THAT(E.message(), testing::HasSubstr(Msg)) << S;
	});
	}
	};
	ExpectErr("Unexpected EOF", "");
	ExpectErr("Unexpected EOF", "[");
	ExpectErr("Text after end of document", "[][]");
	ExpectErr("Invalid JSON value (false?)", "fuzzy");
	ExpectErr("Expected , or ]", "[2?]");
	ExpectErr("Expected object key", "{a:2}");
	ExpectErr("Expected : after object key", R"({"a",2})");
	ExpectErr("Expected , or } after object property", R"({"a":2 "b":3})");
	ExpectErr("Invalid JSON value", R"([&%!])");
	ExpectErr("Invalid JSON value (number?)", "1e1.0");
	ExpectErr("Unterminated string", R"("abc\"def)");
	ExpectErr("Control character in string", "\"abc\ndef\"");
	ExpectErr("Invalid escape sequence", R"("\030")");
	ExpectErr("Invalid \\u escape sequence", R"("\usuck")");
	ExpectErr("[3:3, byte=19]", R"({
	"valid": 1,
	invalid: 2
	})");
	ExpectErr("Invalid UTF-8 sequence", "\"\xC0\x80\""); // WTF-8 null
	}

	// Direct tests of isUTF8 and fixUTF8. Internal uses are also tested elsewhere.
	TEST(JSONTest, UTF8) {
	for (const char *Valid : {
	"this is ASCII text",
	"thïs tëxt häs BMP chäräctërs",
	"𐌶𐌰L𐌾𐍈 C𐍈𐌼𐌴𐍃",
	}) {
	EXPECT_TRUE(isUTF8(Valid)) << Valid;
	EXPECT_EQ(fixUTF8(Valid), Valid);
	}
	for (auto Invalid : std::vector<std::pair<const char , const char >>{
	{"lone trailing \x81\x82 bytes", "lone trailing �� bytes"},
	{"missing trailing \xD0 bytes", "missing trailing � bytes"},
	{"truncated character \xD0", "truncated character �"},
	{"not \xC1\x80 the \xE0\x9f\xBF shortest \xF0\x83\x83\x83 encoding",
	"not �� the �� shortest �� encoding"},
	{"too \xF9\x80\x80\x80\x80 long", "too �� long"},
	{"surrogate \xED\xA0\x80 invalid \xF4\x90\x80\x80",
	"surrogate �� invalid ��"}}) {
	EXPECT_FALSE(isUTF8(Invalid.first)) << Invalid.first;
	EXPECT_EQ(fixUTF8(Invalid.first), Invalid.second);
	}
	}

	TEST(JSONTest, Inspection) {
	llvm::Expected<Value> Doc = parse(R"(
	{
	"null": null,
	"boolean": false,
	"number": 2.78,
	"string": "json",
	"array": [null, true, 3.14, "hello", [1,2,3], {"time": "arrow"}],
	"object": {"fruit": "banana"}
	}
	)");
	EXPECT_TRUE(!!Doc);

	Object *O = Doc->getAsObject();
	ASSERT_TRUE(O);

	EXPECT_FALSE(O->getNull("missing"));
	EXPECT_FALSE(O->getNull("boolean"));
	EXPECT_TRUE(O->getNull("null"));

	EXPECT_EQ(O->getNumber("number"), llvm::Optional<double>(2.78));
	EXPECT_FALSE(O->getInteger("number"));
	EXPECT_EQ(O->getString("string"), llvm::Optional<llvm::StringRef>("json"));
	ASSERT_FALSE(O->getObject("missing"));
	ASSERT_FALSE(O->getObject("array"));
	ASSERT_TRUE(O->getObject("object"));
	EXPECT_EQ(*O->getObject("object"), (Object{{"fruit", "banana"}}));

	Array *A = O->getArray("array");
	ASSERT_TRUE(A);
	EXPECT_EQ((*A)[1].getAsBoolean(), llvm::Optional<bool>(true));
	ASSERT_TRUE((*A)[4].getAsArray());
	EXPECT_EQ((A)[4].getAsArray(), (Array{1, 2, 3}));
	EXPECT_EQ(((A)[4].getAsArray())[1].getAsInteger(),
	llvm::Optional<int64_t>(2));
	int I = 0;
	for (Value &E : *A) {
	if (I++ == 5) {
	ASSERT_TRUE(E.getAsObject());
	EXPECT_EQ(E.getAsObject()->getString("time"),
	llvm::Optional<llvm::StringRef>("arrow"));
	} else
	EXPECT_FALSE(E.getAsObject());
	}
	}

	// Verify special integer handling - we try to preserve exact int64 values.
	TEST(JSONTest, Integers) {
	struct {
	const char *Desc;
	Value Val;
	const char *Str;
	llvm::Optional<int64_t> AsInt;
	llvm::Optional<double> AsNumber;
	} TestCases[] = {
	{
	"Non-integer. Stored as double, not convertible.",
	double{1.5},
	"1.5",
	llvm::None,
	1.5,
	},

	{
	"Integer, not exact double. Stored as int64, convertible.",
	int64_t{0x4000000000000001},
	"4611686018427387905",
	int64_t{0x4000000000000001},
	double{0x4000000000000000},
	},

	{
	"Negative integer, not exact double. Stored as int64, convertible.",
	int64_t{-0x4000000000000001},
	"-4611686018427387905",
	int64_t{-0x4000000000000001},
	double{-0x4000000000000000},
	},

	{
	"Dynamically exact integer. Stored as double, convertible.",
	double{0x6000000000000000},
	"6.9175290276410819e+18",
	int64_t{0x6000000000000000},
	double{0x6000000000000000},
	},

	{
	"Dynamically integer, >64 bits. Stored as double, not convertible.",
	1.5 * double{0x8000000000000000},
	"1.3835058055282164e+19",
	llvm::None,
	1.5 * double{0x8000000000000000},
	},
	};
	for (const auto &T : TestCases) {
	EXPECT_EQ(T.Str, s(T.Val)) << T.Desc;
	llvm::Expected<Value> Doc = parse(T.Str);
	EXPECT_TRUE(!!Doc) << T.Desc;
	EXPECT_EQ(Doc->getAsInteger(), T.AsInt) << T.Desc;
	EXPECT_EQ(Doc->getAsNumber(), T.AsNumber) << T.Desc;
	EXPECT_EQ(T.Val, *Doc) << T.Desc;
	EXPECT_EQ(T.Str, s(*Doc)) << T.Desc;
	}
	}

	// Sample struct with typical JSON-mapping rules.
	struct CustomStruct {
	CustomStruct() : B(false) {}
	CustomStruct(std::string S, llvm::Optional<int> I, bool B)
	: S(S), I(I), B(B) {}
	std::string S;
	llvm::Optional<int> I;
	bool B;
	};
	inline bool operator==(const CustomStruct &L, const CustomStruct &R) {
	return L.S == R.S && L.I == R.I && L.B == R.B;
	}
	inline llvm::raw_ostream &operator<<(llvm::raw_ostream &OS,
	const CustomStruct &S) {
	return OS << "(" << S.S << ", " << (S.I ? std::to_string(*S.I) : "None")
	<< ", " << S.B << ")";
	}
	bool fromJSON(const Value &E, CustomStruct &R) {
	ObjectMapper O(E);
	if (!O \|\| !O.map("str", R.S) \|\| !O.map("int", R.I))
	return false;
	O.map("bool", R.B);
	return true;
	}

	TEST(JSONTest, Deserialize) {
	std::map<std::string, std::vector<CustomStruct>> R;
	CustomStruct ExpectedStruct = {"foo", 42, true};
	std::map<std::string, std::vector<CustomStruct>> Expected;
	Value J = Object{
	{"foo",
	Array{
	Object{
	{"str", "foo"},
	{"int", 42},
	{"bool", true},
	{"unknown", "ignored"},
	},
	Object{{"str", "bar"}},
	Object{
	{"str", "baz"}, {"bool", "string"}, // OK, deserialize ignores.
	},
	}}};
	Expected["foo"] = {
	CustomStruct("foo", 42, true),
	CustomStruct("bar", llvm::None, false),
	CustomStruct("baz", llvm::None, false),
	};
	ASSERT_TRUE(fromJSON(J, R));
	EXPECT_EQ(R, Expected);

	CustomStruct V;
	EXPECT_FALSE(fromJSON(nullptr, V)) << "Not an object " << V;
	EXPECT_FALSE(fromJSON(Object{}, V)) << "Missing required field " << V;
	EXPECT_FALSE(fromJSON(Object{{"str", 1}}, V)) << "Wrong type " << V;
	// Optional<T> must parse as the correct type if present.
	EXPECT_FALSE(fromJSON(Object{{"str", 1}, {"int", "string"}}, V))
	<< "Wrong type for Optional<T> " << V;
	}

	} // namespace
	} // namespace json
	} // namespace llvm