src/v8/src/inspector/v8-debugger-script.cc - cobalt - Git at Google

 // Copyright 2014 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.

 #include "src/inspector/v8-debugger-script.h"

 #include "src/inspector/inspected-context.h"
 #include "src/inspector/string-util.h"
 #include "src/inspector/wasm-translation.h"

 namespace v8_inspector {

 namespace {

 const char hexDigits[17] = "0123456789ABCDEF";

 void appendUnsignedAsHex(uint64_t number, String16Builder* destination) {
   for (size_t i = 0; i < 8; ++i) {
     UChar c = hexDigits[number & 0xF];
     destination->append(c);
     number >>= 4;
   }
 }

 // Hash algorithm for substrings is described in "Über die Komplexität der
 // Multiplikation in
 // eingeschränkten Branchingprogrammmodellen" by Woelfe.
 // http://opendatastructures.org/versions/edition-0.1d/ods-java/node33.html#SECTION00832000000000000000
 String16 calculateHash(const String16& str) {
   static uint64_t prime[] = {0x3FB75161, 0xAB1F4E4F, 0x82675BC5, 0xCD924D35,
                              0x81ABE279};
   static uint64_t random[] = {0x67452301, 0xEFCDAB89, 0x98BADCFE, 0x10325476,
                               0xC3D2E1F0};
   static uint32_t randomOdd[] = {0xB4663807, 0xCC322BF5, 0xD4F91BBD, 0xA7BEA11D,
                                  0x8F462907};

   uint64_t hashes[] = {0, 0, 0, 0, 0};
   uint64_t zi[] = {1, 1, 1, 1, 1};

   const size_t hashesSize = arraysize(hashes);

   size_t current = 0;
   const uint32_t* data = nullptr;
   size_t sizeInBytes = sizeof(UChar) * str.length();
   data = reinterpret_cast<const uint32_t*>(str.characters16());
   for (size_t i = 0; i < sizeInBytes / 4; i += 4) {
 #if V8_TARGET_LITTLE_ENDIAN
     uint32_t v = data[i];
 #else
     uint32_t v = (data[i] << 16) | (data[i] >> 16);
 #endif
     uint64_t xi = v * randomOdd[current] & 0x7FFFFFFF;
     hashes[current] = (hashes[current] + zi[current] * xi) % prime[current];
     zi[current] = (zi[current] * random[current]) % prime[current];
     current = current == hashesSize - 1 ? 0 : current + 1;
   }
   if (sizeInBytes % 4) {
     uint32_t v = 0;
     for (size_t i = sizeInBytes - sizeInBytes % 4; i < sizeInBytes; ++i) {
       v <<= 8;
 #if V8_TARGET_LITTLE_ENDIAN
       v |= reinterpret_cast<const uint8_t*>(data)[i];
 #else
       if (i % 2) {
         v |= reinterpret_cast<const uint8_t*>(data)[i - 1];
       } else {
         v |= reinterpret_cast<const uint8_t*>(data)[i + 1];
       }
 #endif
     }
     uint64_t xi = v * randomOdd[current] & 0x7FFFFFFF;
     hashes[current] = (hashes[current] + zi[current] * xi) % prime[current];
     zi[current] = (zi[current] * random[current]) % prime[current];
     current = current == hashesSize - 1 ? 0 : current + 1;
   }

   for (size_t i = 0; i < hashesSize; ++i)
     hashes[i] = (hashes[i] + zi[i] * (prime[i] - 1)) % prime[i];

   String16Builder hash;
   for (size_t i = 0; i < hashesSize; ++i) appendUnsignedAsHex(hashes[i], &hash);
   return hash.toString();
 }

 void TranslateProtocolLocationToV8Location(WasmTranslation* wasmTranslation,
                                            v8::debug::Location* loc,
                                            const String16& scriptId,
                                            const String16& expectedV8ScriptId) {
   if (loc->IsEmpty()) return;
   int lineNumber = loc->GetLineNumber();
   int columnNumber = loc->GetColumnNumber();
   String16 translatedScriptId = scriptId;
   wasmTranslation->TranslateProtocolLocationToWasmScriptLocation(
       &translatedScriptId, &lineNumber, &columnNumber);
   DCHECK_EQ(expectedV8ScriptId.utf8(), translatedScriptId.utf8());
   *loc = v8::debug::Location(lineNumber, columnNumber);
 }

 void TranslateV8LocationToProtocolLocation(
     WasmTranslation* wasmTranslation, v8::debug::Location* loc,
     const String16& scriptId, const String16& expectedProtocolScriptId) {
   int lineNumber = loc->GetLineNumber();
   int columnNumber = loc->GetColumnNumber();
   String16 translatedScriptId = scriptId;
   wasmTranslation->TranslateWasmScriptLocationToProtocolLocation(
       &translatedScriptId, &lineNumber, &columnNumber);
   DCHECK_EQ(expectedProtocolScriptId.utf8(), translatedScriptId.utf8());
   *loc = v8::debug::Location(lineNumber, columnNumber);
 }

 class ActualScript : public V8DebuggerScript {
   friend class V8DebuggerScript;

  public:
   ActualScript(v8::Isolate* isolate, v8::Local<v8::debug::Script> script,
                bool isLiveEdit)
       : V8DebuggerScript(isolate, String16::fromInteger(script->Id()),
                          GetNameOrSourceUrl(script)),
         m_isLiveEdit(isLiveEdit) {
     v8::Local<v8::String> tmp;
     if (script->SourceURL().ToLocal(&tmp)) m_sourceURL = toProtocolString(tmp);
     if (script->SourceMappingURL().ToLocal(&tmp))
       m_sourceMappingURL = toProtocolString(tmp);
     m_startLine = script->LineOffset();
     m_startColumn = script->ColumnOffset();
     std::vector<int> lineEnds = script->LineEnds();
     CHECK(lineEnds.size());
     int source_length = lineEnds[lineEnds.size() - 1];
     if (lineEnds.size()) {
       m_endLine = static_cast<int>(lineEnds.size()) + m_startLine - 1;
       if (lineEnds.size() > 1) {
         m_endColumn = source_length - lineEnds[lineEnds.size() - 2] - 1;
       } else {
         m_endColumn = source_length + m_startColumn;
       }
     } else {
       m_endLine = m_startLine;
       m_endColumn = m_startColumn;
     }

     USE(script->ContextId().To(&m_executionContextId));

     if (script->Source().ToLocal(&tmp)) {
       m_source = toProtocolString(tmp);
     }

     m_isModule = script->IsModule();

     m_script.Reset(m_isolate, script);
   }

   bool isLiveEdit() const override { return m_isLiveEdit; }
   bool isModule() const override { return m_isModule; }

   const String16& sourceMappingURL() const override {
     return m_sourceMappingURL;
   }

   void setSourceMappingURL(const String16& sourceMappingURL) override {
     m_sourceMappingURL = sourceMappingURL;
   }

   void setSource(const String16& newSource, bool preview,
                  bool* stackChanged) override {
     DCHECK(!isModule());
     v8::HandleScope scope(m_isolate);
     v8::Local<v8::String> v8Source = toV8String(m_isolate, newSource);
     if (!m_script.Get(m_isolate)->SetScriptSource(v8Source, preview,
                                                   stackChanged)) {
       return;
     }
     if (preview) return;
     m_source = newSource;
     m_hash = String16();
   }

   bool getPossibleBreakpoints(
       const v8::debug::Location& start, const v8::debug::Location& end,
       bool restrictToFunction,
       std::vector<v8::debug::BreakLocation>* locations) override {
     v8::HandleScope scope(m_isolate);
     v8::Local<v8::debug::Script> script = m_script.Get(m_isolate);
     std::vector<v8::debug::BreakLocation> allLocations;
     if (!script->GetPossibleBreakpoints(start, end, restrictToFunction,
                                         &allLocations)) {
       return false;
     }
     if (!allLocations.size()) return true;
     v8::debug::BreakLocation current = allLocations[0];
     for (size_t i = 1; i < allLocations.size(); ++i) {
       if (allLocations[i].GetLineNumber() == current.GetLineNumber() &&
           allLocations[i].GetColumnNumber() == current.GetColumnNumber()) {
         if (allLocations[i].type() != v8::debug::kCommonBreakLocation) {
           DCHECK(allLocations[i].type() == v8::debug::kCallBreakLocation ||
                  allLocations[i].type() == v8::debug::kReturnBreakLocation);
           // debugger can returns more then one break location at the same
           // source location, e.g. foo() - in this case there are two break
           // locations before foo: for statement and for function call, we can
           // merge them for inspector and report only one with call type.
           current = allLocations[i];
         }
       } else {
         // we assume that returned break locations are sorted.
         DCHECK(
             allLocations[i].GetLineNumber() > current.GetLineNumber() ||
             (allLocations[i].GetColumnNumber() >= current.GetColumnNumber() &&
              allLocations[i].GetLineNumber() == current.GetLineNumber()));
         locations->push_back(current);
         current = allLocations[i];
       }
     }
     locations->push_back(current);
     return true;
   }

   void resetBlackboxedStateCache() override {
     v8::HandleScope scope(m_isolate);
     v8::debug::ResetBlackboxedStateCache(m_isolate, m_script.Get(m_isolate));
   }

   int offset(int lineNumber, int columnNumber) const override {
     v8::HandleScope scope(m_isolate);
     return m_script.Get(m_isolate)->GetSourceOffset(
         v8::debug::Location(lineNumber, columnNumber));
   }

   v8::debug::Location location(int offset) const override {
     v8::HandleScope scope(m_isolate);
     return m_script.Get(m_isolate)->GetSourceLocation(offset);
   }

  private:
   String16 GetNameOrSourceUrl(v8::Local<v8::debug::Script> script) {
     v8::Local<v8::String> name;
     if (script->Name().ToLocal(&name) || script->SourceURL().ToLocal(&name))
       return toProtocolString(name);
     return String16();
   }

   v8::Local<v8::debug::Script> script() const override {
     return m_script.Get(m_isolate);
   }

   String16 m_sourceMappingURL;
   bool m_isLiveEdit = false;
   bool m_isModule = false;
   v8::Global<v8::debug::Script> m_script;
 };

 class WasmVirtualScript : public V8DebuggerScript {
   friend class V8DebuggerScript;

  public:
   WasmVirtualScript(v8::Isolate* isolate, WasmTranslation* wasmTranslation,
                     v8::Local<v8::debug::WasmScript> script, String16 id,
                     String16 url, String16 source)
       : V8DebuggerScript(isolate, std::move(id), std::move(url)),
         m_script(isolate, script),
         m_wasmTranslation(wasmTranslation) {
     int num_lines = 0;
     int last_newline = -1;
     size_t next_newline = source.find('\n', last_newline + 1);
     while (next_newline != String16::kNotFound) {
       last_newline = static_cast<int>(next_newline);
       next_newline = source.find('\n', last_newline + 1);
       ++num_lines;
     }
     m_endLine = num_lines;
     m_endColumn = static_cast<int>(source.length()) - last_newline - 1;
     m_source = std::move(source);
     m_executionContextId = script->ContextId().ToChecked();
   }

   const String16& sourceMappingURL() const override { return emptyString(); }
   bool isLiveEdit() const override { return false; }
   bool isModule() const override { return false; }
   void setSourceMappingURL(const String16&) override {}
   void setSource(const String16&, bool, bool*) override { UNREACHABLE(); }

   bool getPossibleBreakpoints(
       const v8::debug::Location& start, const v8::debug::Location& end,
       bool restrictToFunction,
       std::vector<v8::debug::BreakLocation>* locations) override {
     v8::HandleScope scope(m_isolate);
     v8::Local<v8::debug::Script> script = m_script.Get(m_isolate);
     String16 v8ScriptId = String16::fromInteger(script->Id());

     v8::debug::Location translatedStart = start;
     TranslateProtocolLocationToV8Location(m_wasmTranslation, &translatedStart,
                                           scriptId(), v8ScriptId);

     v8::debug::Location translatedEnd = end;
     if (translatedEnd.IsEmpty()) {
       // Stop before the start of the next function.
       translatedEnd =
           v8::debug::Location(translatedStart.GetLineNumber() + 1, 0);
     } else {
       TranslateProtocolLocationToV8Location(m_wasmTranslation, &translatedEnd,
                                             scriptId(), v8ScriptId);
     }

     bool success = script->GetPossibleBreakpoints(
         translatedStart, translatedEnd, restrictToFunction, locations);
     for (v8::debug::BreakLocation& loc : *locations) {
       TranslateV8LocationToProtocolLocation(m_wasmTranslation, &loc, v8ScriptId,
                                             scriptId());
     }
     return success;
   }

   void resetBlackboxedStateCache() override {}

   int offset(int lineNumber, int columnNumber) const override {
     return kNoOffset;
   }

   v8::debug::Location location(int offset) const override {
     return v8::debug::Location();
   }

  private:
   static const String16& emptyString() {
     static const String16 singleEmptyString;
     return singleEmptyString;
   }

   v8::Local<v8::debug::Script> script() const override {
     return m_script.Get(m_isolate);
   }

   v8::Global<v8::debug::WasmScript> m_script;
   WasmTranslation* m_wasmTranslation;
 };

 }  // namespace

 std::unique_ptr<V8DebuggerScript> V8DebuggerScript::Create(
     v8::Isolate* isolate, v8::Local<v8::debug::Script> scriptObj,
     bool isLiveEdit) {
   return std::unique_ptr<ActualScript>(
       new ActualScript(isolate, scriptObj, isLiveEdit));
 }

 std::unique_ptr<V8DebuggerScript> V8DebuggerScript::CreateWasm(
     v8::Isolate* isolate, WasmTranslation* wasmTranslation,
     v8::Local<v8::debug::WasmScript> underlyingScript, String16 id,
     String16 url, String16 source) {
   return std::unique_ptr<WasmVirtualScript>(
       new WasmVirtualScript(isolate, wasmTranslation, underlyingScript,
                             std::move(id), std::move(url), std::move(source)));
 }

 V8DebuggerScript::V8DebuggerScript(v8::Isolate* isolate, String16 id,
                                    String16 url)
     : m_id(std::move(id)), m_url(std::move(url)), m_isolate(isolate) {}

 V8DebuggerScript::~V8DebuggerScript() {}

 const String16& V8DebuggerScript::sourceURL() const {
   return m_sourceURL.isEmpty() ? m_url : m_sourceURL;
 }

 const String16& V8DebuggerScript::hash() const {
   if (m_hash.isEmpty()) m_hash = calculateHash(source());
   DCHECK(!m_hash.isEmpty());
   return m_hash;
 }

 void V8DebuggerScript::setSourceURL(const String16& sourceURL) {
   m_sourceURL = sourceURL;
 }

 bool V8DebuggerScript::setBreakpoint(const String16& condition,
                                      v8::debug::Location* loc, int* id) const {
   v8::HandleScope scope(m_isolate);
   return script()->SetBreakpoint(toV8String(m_isolate, condition), loc, id);
 }

 }  // namespace v8_inspector
	// Copyright 2014 the V8 project authors. All rights reserved.
	// Use of this source code is governed by a BSD-style license that can be
	// found in the LICENSE file.

	#include "src/inspector/v8-debugger-script.h"

	#include "src/inspector/inspected-context.h"
	#include "src/inspector/string-util.h"
	#include "src/inspector/wasm-translation.h"

	namespace v8_inspector {

	namespace {

	const char hexDigits[17] = "0123456789ABCDEF";

	void appendUnsignedAsHex(uint64_t number, String16Builder* destination) {
	for (size_t i = 0; i < 8; ++i) {
	UChar c = hexDigits[number & 0xF];
	destination->append(c);
	number >>= 4;
	}
	}

	// Hash algorithm for substrings is described in "Über die Komplexität der
	// Multiplikation in
	// eingeschränkten Branchingprogrammmodellen" by Woelfe.
	// http://opendatastructures.org/versions/edition-0.1d/ods-java/node33.html#SECTION00832000000000000000
	String16 calculateHash(const String16& str) {
	static uint64_t prime[] = {0x3FB75161, 0xAB1F4E4F, 0x82675BC5, 0xCD924D35,
	0x81ABE279};
	static uint64_t random[] = {0x67452301, 0xEFCDAB89, 0x98BADCFE, 0x10325476,
	0xC3D2E1F0};
	static uint32_t randomOdd[] = {0xB4663807, 0xCC322BF5, 0xD4F91BBD, 0xA7BEA11D,
	0x8F462907};

	uint64_t hashes[] = {0, 0, 0, 0, 0};
	uint64_t zi[] = {1, 1, 1, 1, 1};

	const size_t hashesSize = arraysize(hashes);

	size_t current = 0;
	const uint32_t* data = nullptr;
	size_t sizeInBytes = sizeof(UChar) * str.length();
	data = reinterpret_cast<const uint32_t*>(str.characters16());
	for (size_t i = 0; i < sizeInBytes / 4; i += 4) {
	#if V8_TARGET_LITTLE_ENDIAN
	uint32_t v = data[i];
	#else
	uint32_t v = (data[i] << 16) \| (data[i] >> 16);
	#endif
	uint64_t xi = v * randomOdd[current] & 0x7FFFFFFF;
	hashes[current] = (hashes[current] + zi[current] * xi) % prime[current];
	zi[current] = (zi[current] * random[current]) % prime[current];
	current = current == hashesSize - 1 ? 0 : current + 1;
	}
	if (sizeInBytes % 4) {
	uint32_t v = 0;
	for (size_t i = sizeInBytes - sizeInBytes % 4; i < sizeInBytes; ++i) {
	v <<= 8;
	#if V8_TARGET_LITTLE_ENDIAN
	v \|= reinterpret_cast<const uint8_t*>(data)[i];
	#else
	if (i % 2) {
	v \|= reinterpret_cast<const uint8_t*>(data)[i - 1];
	} else {
	v \|= reinterpret_cast<const uint8_t*>(data)[i + 1];
	}
	#endif
	}
	uint64_t xi = v * randomOdd[current] & 0x7FFFFFFF;
	hashes[current] = (hashes[current] + zi[current] * xi) % prime[current];
	zi[current] = (zi[current] * random[current]) % prime[current];
	current = current == hashesSize - 1 ? 0 : current + 1;
	}

	for (size_t i = 0; i < hashesSize; ++i)
	hashes[i] = (hashes[i] + zi[i] * (prime[i] - 1)) % prime[i];

	String16Builder hash;
	for (size_t i = 0; i < hashesSize; ++i) appendUnsignedAsHex(hashes[i], &hash);
	return hash.toString();
	}

	void TranslateProtocolLocationToV8Location(WasmTranslation* wasmTranslation,
	v8::debug::Location* loc,
	const String16& scriptId,
	const String16& expectedV8ScriptId) {
	if (loc->IsEmpty()) return;
	int lineNumber = loc->GetLineNumber();
	int columnNumber = loc->GetColumnNumber();
	String16 translatedScriptId = scriptId;
	wasmTranslation->TranslateProtocolLocationToWasmScriptLocation(
	&translatedScriptId, &lineNumber, &columnNumber);
	DCHECK_EQ(expectedV8ScriptId.utf8(), translatedScriptId.utf8());
	*loc = v8::debug::Location(lineNumber, columnNumber);
	}

	void TranslateV8LocationToProtocolLocation(
	WasmTranslation* wasmTranslation, v8::debug::Location* loc,
	const String16& scriptId, const String16& expectedProtocolScriptId) {
	int lineNumber = loc->GetLineNumber();
	int columnNumber = loc->GetColumnNumber();
	String16 translatedScriptId = scriptId;
	wasmTranslation->TranslateWasmScriptLocationToProtocolLocation(
	&translatedScriptId, &lineNumber, &columnNumber);
	DCHECK_EQ(expectedProtocolScriptId.utf8(), translatedScriptId.utf8());
	*loc = v8::debug::Location(lineNumber, columnNumber);
	}

	class ActualScript : public V8DebuggerScript {
	friend class V8DebuggerScript;

	public:
	ActualScript(v8::Isolate* isolate, v8::Local<v8::debug::Script> script,
	bool isLiveEdit)
	: V8DebuggerScript(isolate, String16::fromInteger(script->Id()),
	GetNameOrSourceUrl(script)),
	m_isLiveEdit(isLiveEdit) {
	v8::Local<v8::String> tmp;
	if (script->SourceURL().ToLocal(&tmp)) m_sourceURL = toProtocolString(tmp);
	if (script->SourceMappingURL().ToLocal(&tmp))
	m_sourceMappingURL = toProtocolString(tmp);
	m_startLine = script->LineOffset();
	m_startColumn = script->ColumnOffset();
	std::vector<int> lineEnds = script->LineEnds();
	CHECK(lineEnds.size());
	int source_length = lineEnds[lineEnds.size() - 1];
	if (lineEnds.size()) {
	m_endLine = static_cast<int>(lineEnds.size()) + m_startLine - 1;
	if (lineEnds.size() > 1) {
	m_endColumn = source_length - lineEnds[lineEnds.size() - 2] - 1;
	} else {
	m_endColumn = source_length + m_startColumn;
	}
	} else {
	m_endLine = m_startLine;
	m_endColumn = m_startColumn;
	}

	USE(script->ContextId().To(&m_executionContextId));

	if (script->Source().ToLocal(&tmp)) {
	m_source = toProtocolString(tmp);
	}

	m_isModule = script->IsModule();

	m_script.Reset(m_isolate, script);
	}

	bool isLiveEdit() const override { return m_isLiveEdit; }
	bool isModule() const override { return m_isModule; }

	const String16& sourceMappingURL() const override {
	return m_sourceMappingURL;
	}

	void setSourceMappingURL(const String16& sourceMappingURL) override {
	m_sourceMappingURL = sourceMappingURL;
	}

	void setSource(const String16& newSource, bool preview,
	bool* stackChanged) override {
	DCHECK(!isModule());
	v8::HandleScope scope(m_isolate);
	v8::Local<v8::String> v8Source = toV8String(m_isolate, newSource);
	if (!m_script.Get(m_isolate)->SetScriptSource(v8Source, preview,
	stackChanged)) {
	return;
	}
	if (preview) return;
	m_source = newSource;
	m_hash = String16();
	}

	bool getPossibleBreakpoints(
	const v8::debug::Location& start, const v8::debug::Location& end,
	bool restrictToFunction,
	std::vector<v8::debug::BreakLocation>* locations) override {
	v8::HandleScope scope(m_isolate);
	v8::Local<v8::debug::Script> script = m_script.Get(m_isolate);
	std::vector<v8::debug::BreakLocation> allLocations;
	if (!script->GetPossibleBreakpoints(start, end, restrictToFunction,
	&allLocations)) {
	return false;
	}
	if (!allLocations.size()) return true;
	v8::debug::BreakLocation current = allLocations[0];
	for (size_t i = 1; i < allLocations.size(); ++i) {
	if (allLocations[i].GetLineNumber() == current.GetLineNumber() &&
	allLocations[i].GetColumnNumber() == current.GetColumnNumber()) {
	if (allLocations[i].type() != v8::debug::kCommonBreakLocation) {
	DCHECK(allLocations[i].type() == v8::debug::kCallBreakLocation \|\|
	allLocations[i].type() == v8::debug::kReturnBreakLocation);
	// debugger can returns more then one break location at the same
	// source location, e.g. foo() - in this case there are two break
	// locations before foo: for statement and for function call, we can
	// merge them for inspector and report only one with call type.
	current = allLocations[i];
	}
	} else {
	// we assume that returned break locations are sorted.
	DCHECK(
	allLocations[i].GetLineNumber() > current.GetLineNumber() \|\|
	(allLocations[i].GetColumnNumber() >= current.GetColumnNumber() &&
	allLocations[i].GetLineNumber() == current.GetLineNumber()));
	locations->push_back(current);
	current = allLocations[i];
	}
	}
	locations->push_back(current);
	return true;
	}

	void resetBlackboxedStateCache() override {
	v8::HandleScope scope(m_isolate);
	v8::debug::ResetBlackboxedStateCache(m_isolate, m_script.Get(m_isolate));
	}

	int offset(int lineNumber, int columnNumber) const override {
	v8::HandleScope scope(m_isolate);
	return m_script.Get(m_isolate)->GetSourceOffset(
	v8::debug::Location(lineNumber, columnNumber));
	}

	v8::debug::Location location(int offset) const override {
	v8::HandleScope scope(m_isolate);
	return m_script.Get(m_isolate)->GetSourceLocation(offset);
	}

	private:
	String16 GetNameOrSourceUrl(v8::Local<v8::debug::Script> script) {
	v8::Local<v8::String> name;
	if (script->Name().ToLocal(&name) \|\| script->SourceURL().ToLocal(&name))
	return toProtocolString(name);
	return String16();
	}

	v8::Local<v8::debug::Script> script() const override {
	return m_script.Get(m_isolate);
	}

	String16 m_sourceMappingURL;
	bool m_isLiveEdit = false;
	bool m_isModule = false;
	v8::Global<v8::debug::Script> m_script;
	};

	class WasmVirtualScript : public V8DebuggerScript {
	friend class V8DebuggerScript;

	public:
	WasmVirtualScript(v8::Isolate* isolate, WasmTranslation* wasmTranslation,
	v8::Local<v8::debug::WasmScript> script, String16 id,
	String16 url, String16 source)
	: V8DebuggerScript(isolate, std::move(id), std::move(url)),
	m_script(isolate, script),
	m_wasmTranslation(wasmTranslation) {
	int num_lines = 0;
	int last_newline = -1;
	size_t next_newline = source.find('\n', last_newline + 1);
	while (next_newline != String16::kNotFound) {
	last_newline = static_cast<int>(next_newline);
	next_newline = source.find('\n', last_newline + 1);
	++num_lines;
	}
	m_endLine = num_lines;
	m_endColumn = static_cast<int>(source.length()) - last_newline - 1;
	m_source = std::move(source);
	m_executionContextId = script->ContextId().ToChecked();
	}

	const String16& sourceMappingURL() const override { return emptyString(); }
	bool isLiveEdit() const override { return false; }
	bool isModule() const override { return false; }
	void setSourceMappingURL(const String16&) override {}
	void setSource(const String16&, bool, bool*) override { UNREACHABLE(); }

	bool getPossibleBreakpoints(
	const v8::debug::Location& start, const v8::debug::Location& end,
	bool restrictToFunction,
	std::vector<v8::debug::BreakLocation>* locations) override {
	v8::HandleScope scope(m_isolate);
	v8::Local<v8::debug::Script> script = m_script.Get(m_isolate);
	String16 v8ScriptId = String16::fromInteger(script->Id());

	v8::debug::Location translatedStart = start;
	TranslateProtocolLocationToV8Location(m_wasmTranslation, &translatedStart,
	scriptId(), v8ScriptId);

	v8::debug::Location translatedEnd = end;
	if (translatedEnd.IsEmpty()) {
	// Stop before the start of the next function.
	translatedEnd =
	v8::debug::Location(translatedStart.GetLineNumber() + 1, 0);
	} else {
	TranslateProtocolLocationToV8Location(m_wasmTranslation, &translatedEnd,
	scriptId(), v8ScriptId);
	}

	bool success = script->GetPossibleBreakpoints(
	translatedStart, translatedEnd, restrictToFunction, locations);
	for (v8::debug::BreakLocation& loc : *locations) {
	TranslateV8LocationToProtocolLocation(m_wasmTranslation, &loc, v8ScriptId,
	scriptId());
	}
	return success;
	}

	void resetBlackboxedStateCache() override {}

	int offset(int lineNumber, int columnNumber) const override {
	return kNoOffset;
	}

	v8::debug::Location location(int offset) const override {
	return v8::debug::Location();
	}

	private:
	static const String16& emptyString() {
	static const String16 singleEmptyString;
	return singleEmptyString;
	}

	v8::Local<v8::debug::Script> script() const override {
	return m_script.Get(m_isolate);
	}

	v8::Global<v8::debug::WasmScript> m_script;
	WasmTranslation* m_wasmTranslation;
	};

	} // namespace

	std::unique_ptr<V8DebuggerScript> V8DebuggerScript::Create(
	v8::Isolate* isolate, v8::Local<v8::debug::Script> scriptObj,
	bool isLiveEdit) {
	return std::unique_ptr<ActualScript>(
	new ActualScript(isolate, scriptObj, isLiveEdit));
	}

	std::unique_ptr<V8DebuggerScript> V8DebuggerScript::CreateWasm(
	v8::Isolate* isolate, WasmTranslation* wasmTranslation,
	v8::Local<v8::debug::WasmScript> underlyingScript, String16 id,
	String16 url, String16 source) {
	return std::unique_ptr<WasmVirtualScript>(
	new WasmVirtualScript(isolate, wasmTranslation, underlyingScript,
	std::move(id), std::move(url), std::move(source)));
	}

	V8DebuggerScript::V8DebuggerScript(v8::Isolate* isolate, String16 id,
	String16 url)
	: m_id(std::move(id)), m_url(std::move(url)), m_isolate(isolate) {}

	V8DebuggerScript::~V8DebuggerScript() {}

	const String16& V8DebuggerScript::sourceURL() const {
	return m_sourceURL.isEmpty() ? m_url : m_sourceURL;
	}

	const String16& V8DebuggerScript::hash() const {
	if (m_hash.isEmpty()) m_hash = calculateHash(source());
	DCHECK(!m_hash.isEmpty());
	return m_hash;
	}

	void V8DebuggerScript::setSourceURL(const String16& sourceURL) {
	m_sourceURL = sourceURL;
	}

	bool V8DebuggerScript::setBreakpoint(const String16& condition,
	v8::debug::Location* loc, int* id) const {
	v8::HandleScope scope(m_isolate);
	return script()->SetBreakpoint(toV8String(m_isolate, condition), loc, id);
	}

	} // namespace v8_inspector