llvm-project/clang/tools/clang-diff/ClangDiff.cpp

537 lines
16 KiB
C++

//===- ClangDiff.cpp - compare source files by AST nodes ------*- 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
//
//===----------------------------------------------------------------------===//
//
// This file implements a tool for syntax tree based comparison using
// Tooling/ASTDiff.
//
//===----------------------------------------------------------------------===//
#include "clang/Tooling/ASTDiff/ASTDiff.h"
#include "clang/Tooling/CommonOptionsParser.h"
#include "clang/Tooling/Tooling.h"
#include "llvm/Support/CommandLine.h"
using namespace llvm;
using namespace clang;
using namespace clang::tooling;
static cl::OptionCategory ClangDiffCategory("clang-diff options");
static cl::opt<bool>
ASTDump("ast-dump",
cl::desc("Print the internal representation of the AST."),
cl::init(false), cl::cat(ClangDiffCategory));
static cl::opt<bool> ASTDumpJson(
"ast-dump-json",
cl::desc("Print the internal representation of the AST as JSON."),
cl::init(false), cl::cat(ClangDiffCategory));
static cl::opt<bool> PrintMatches("dump-matches",
cl::desc("Print the matched nodes."),
cl::init(false), cl::cat(ClangDiffCategory));
static cl::opt<bool> HtmlDiff("html",
cl::desc("Output a side-by-side diff in HTML."),
cl::init(false), cl::cat(ClangDiffCategory));
static cl::opt<std::string> SourcePath(cl::Positional, cl::desc("<source>"),
cl::Required,
cl::cat(ClangDiffCategory));
static cl::opt<std::string> DestinationPath(cl::Positional,
cl::desc("<destination>"),
cl::Optional,
cl::cat(ClangDiffCategory));
static cl::opt<std::string> StopAfter("stop-diff-after",
cl::desc("<topdown|bottomup>"),
cl::Optional, cl::init(""),
cl::cat(ClangDiffCategory));
static cl::opt<int> MaxSize("s", cl::desc("<maxsize>"), cl::Optional,
cl::init(-1), cl::cat(ClangDiffCategory));
static cl::opt<std::string> BuildPath("p", cl::desc("Build path"), cl::init(""),
cl::Optional, cl::cat(ClangDiffCategory));
static cl::list<std::string> ArgsAfter(
"extra-arg",
cl::desc("Additional argument to append to the compiler command line"),
cl::cat(ClangDiffCategory));
static cl::list<std::string> ArgsBefore(
"extra-arg-before",
cl::desc("Additional argument to prepend to the compiler command line"),
cl::cat(ClangDiffCategory));
static void addExtraArgs(std::unique_ptr<CompilationDatabase> &Compilations) {
if (!Compilations)
return;
auto AdjustingCompilations =
std::make_unique<ArgumentsAdjustingCompilations>(
std::move(Compilations));
AdjustingCompilations->appendArgumentsAdjuster(
getInsertArgumentAdjuster(ArgsBefore, ArgumentInsertPosition::BEGIN));
AdjustingCompilations->appendArgumentsAdjuster(
getInsertArgumentAdjuster(ArgsAfter, ArgumentInsertPosition::END));
Compilations = std::move(AdjustingCompilations);
}
static std::unique_ptr<ASTUnit>
getAST(const std::unique_ptr<CompilationDatabase> &CommonCompilations,
const StringRef Filename) {
std::string ErrorMessage;
std::unique_ptr<CompilationDatabase> Compilations;
if (!CommonCompilations) {
Compilations = CompilationDatabase::autoDetectFromSource(
BuildPath.empty() ? Filename : BuildPath, ErrorMessage);
if (!Compilations) {
llvm::errs()
<< "Error while trying to load a compilation database, running "
"without flags.\n"
<< ErrorMessage;
Compilations =
std::make_unique<clang::tooling::FixedCompilationDatabase>(
".", std::vector<std::string>());
}
}
addExtraArgs(Compilations);
std::array<std::string, 1> Files = {{std::string(Filename)}};
ClangTool Tool(Compilations ? *Compilations : *CommonCompilations, Files);
std::vector<std::unique_ptr<ASTUnit>> ASTs;
Tool.buildASTs(ASTs);
if (ASTs.size() != Files.size())
return nullptr;
return std::move(ASTs[0]);
}
static char hexdigit(int N) { return N &= 0xf, N + (N < 10 ? '0' : 'a' - 10); }
static const char HtmlDiffHeader[] = R"(
<html>
<head>
<meta charset='utf-8'/>
<style>
span.d { color: red; }
span.u { color: #cc00cc; }
span.i { color: green; }
span.m { font-weight: bold; }
span { font-weight: normal; color: black; }
div.code {
width: 48%;
height: 98%;
overflow: scroll;
float: left;
padding: 0 0 0.5% 0.5%;
border: solid 2px LightGrey;
border-radius: 5px;
}
</style>
</head>
<script type='text/javascript'>
highlightStack = []
function clearHighlight() {
while (highlightStack.length) {
var [l, r] = highlightStack.pop()
document.getElementById(l).style.backgroundColor = 'inherit'
if (r[1] != '-')
document.getElementById(r).style.backgroundColor = 'inherit'
}
}
function highlight(event) {
var id = event.target['id']
doHighlight(id)
}
function doHighlight(id) {
clearHighlight()
source = document.getElementById(id)
if (!source.attributes['tid'])
return
var mapped = source
while (mapped && mapped.parentElement && mapped.attributes['tid'].value.substr(1) === '-1')
mapped = mapped.parentElement
var tid = null, target = null
if (mapped) {
tid = mapped.attributes['tid'].value
target = document.getElementById(tid)
}
if (source.parentElement && source.parentElement.classList.contains('code'))
return
source.style.backgroundColor = 'lightgrey'
source.scrollIntoView()
if (target) {
if (mapped === source)
target.style.backgroundColor = 'lightgrey'
target.scrollIntoView()
}
highlightStack.push([id, tid])
location.hash = '#' + id
}
function scrollToBoth() {
doHighlight(location.hash.substr(1))
}
function changed(elem) {
return elem.classList.length == 0
}
function nextChangedNode(prefix, increment, number) {
do {
number += increment
var elem = document.getElementById(prefix + number)
} while(elem && !changed(elem))
return elem ? number : null
}
function handleKey(e) {
var down = e.code === "KeyJ"
var up = e.code === "KeyK"
if (!down && !up)
return
var id = highlightStack[0] ? highlightStack[0][0] : 'R0'
var oldelem = document.getElementById(id)
var number = parseInt(id.substr(1))
var increment = down ? 1 : -1
var lastnumber = number
var prefix = id[0]
do {
number = nextChangedNode(prefix, increment, number)
var elem = document.getElementById(prefix + number)
if (up && elem) {
while (elem.parentElement && changed(elem.parentElement))
elem = elem.parentElement
number = elem.id.substr(1)
}
} while ((down && id !== 'R0' && oldelem.contains(elem)))
if (!number)
number = lastnumber
elem = document.getElementById(prefix + number)
doHighlight(prefix + number)
}
window.onload = scrollToBoth
window.onkeydown = handleKey
</script>
<body>
<div onclick='highlight(event)'>
)";
static void printHtml(raw_ostream &OS, char C) {
switch (C) {
case '&':
OS << "&amp;";
break;
case '<':
OS << "&lt;";
break;
case '>':
OS << "&gt;";
break;
case '\'':
OS << "&#x27;";
break;
case '"':
OS << "&quot;";
break;
default:
OS << C;
}
}
static void printHtml(raw_ostream &OS, const StringRef Str) {
for (char C : Str)
printHtml(OS, C);
}
static std::string getChangeKindAbbr(diff::ChangeKind Kind) {
switch (Kind) {
case diff::None:
return "";
case diff::Delete:
return "d";
case diff::Update:
return "u";
case diff::Insert:
return "i";
case diff::Move:
return "m";
case diff::UpdateMove:
return "u m";
}
llvm_unreachable("Invalid enumeration value.");
}
static unsigned printHtmlForNode(raw_ostream &OS, const diff::ASTDiff &Diff,
diff::SyntaxTree &Tree, bool IsLeft,
diff::NodeId Id, unsigned Offset) {
const diff::Node &Node = Tree.getNode(Id);
char MyTag, OtherTag;
diff::NodeId LeftId, RightId;
diff::NodeId TargetId = Diff.getMapped(Tree, Id);
if (IsLeft) {
MyTag = 'L';
OtherTag = 'R';
LeftId = Id;
RightId = TargetId;
} else {
MyTag = 'R';
OtherTag = 'L';
LeftId = TargetId;
RightId = Id;
}
unsigned Begin, End;
std::tie(Begin, End) = Tree.getSourceRangeOffsets(Node);
const SourceManager &SrcMgr = Tree.getASTContext().getSourceManager();
auto Code = SrcMgr.getBuffer(SrcMgr.getMainFileID())->getBuffer();
for (; Offset < Begin; ++Offset)
printHtml(OS, Code[Offset]);
OS << "<span id='" << MyTag << Id << "' "
<< "tid='" << OtherTag << TargetId << "' ";
OS << "title='";
printHtml(OS, Node.getTypeLabel());
OS << "\n" << LeftId << " -> " << RightId;
std::string Value = Tree.getNodeValue(Node);
if (!Value.empty()) {
OS << "\n";
printHtml(OS, Value);
}
OS << "'";
if (Node.Change != diff::None)
OS << " class='" << getChangeKindAbbr(Node.Change) << "'";
OS << ">";
for (diff::NodeId Child : Node.Children)
Offset = printHtmlForNode(OS, Diff, Tree, IsLeft, Child, Offset);
for (; Offset < End; ++Offset)
printHtml(OS, Code[Offset]);
if (Id == Tree.getRootId()) {
End = Code.size();
for (; Offset < End; ++Offset)
printHtml(OS, Code[Offset]);
}
OS << "</span>";
return Offset;
}
static void printJsonString(raw_ostream &OS, const StringRef Str) {
for (signed char C : Str) {
switch (C) {
case '"':
OS << R"(\")";
break;
case '\\':
OS << R"(\\)";
break;
case '\n':
OS << R"(\n)";
break;
case '\t':
OS << R"(\t)";
break;
default:
if ('\x00' <= C && C <= '\x1f') {
OS << R"(\u00)" << hexdigit(C >> 4) << hexdigit(C);
} else {
OS << C;
}
}
}
}
static void printNodeAttributes(raw_ostream &OS, diff::SyntaxTree &Tree,
diff::NodeId Id) {
const diff::Node &N = Tree.getNode(Id);
OS << R"("id":)" << int(Id);
OS << R"(,"type":")" << N.getTypeLabel() << '"';
auto Offsets = Tree.getSourceRangeOffsets(N);
OS << R"(,"begin":)" << Offsets.first;
OS << R"(,"end":)" << Offsets.second;
std::string Value = Tree.getNodeValue(N);
if (!Value.empty()) {
OS << R"(,"value":")";
printJsonString(OS, Value);
OS << '"';
}
}
static void printNodeAsJson(raw_ostream &OS, diff::SyntaxTree &Tree,
diff::NodeId Id) {
const diff::Node &N = Tree.getNode(Id);
OS << "{";
printNodeAttributes(OS, Tree, Id);
auto Identifier = N.getIdentifier();
auto QualifiedIdentifier = N.getQualifiedIdentifier();
if (Identifier) {
OS << R"(,"identifier":")";
printJsonString(OS, *Identifier);
OS << R"(")";
if (QualifiedIdentifier && *Identifier != *QualifiedIdentifier) {
OS << R"(,"qualified_identifier":")";
printJsonString(OS, *QualifiedIdentifier);
OS << R"(")";
}
}
OS << R"(,"children":[)";
if (N.Children.size() > 0) {
printNodeAsJson(OS, Tree, N.Children[0]);
for (size_t I = 1, E = N.Children.size(); I < E; ++I) {
OS << ",";
printNodeAsJson(OS, Tree, N.Children[I]);
}
}
OS << "]}";
}
static void printNode(raw_ostream &OS, diff::SyntaxTree &Tree,
diff::NodeId Id) {
if (Id.isInvalid()) {
OS << "None";
return;
}
OS << Tree.getNode(Id).getTypeLabel();
std::string Value = Tree.getNodeValue(Id);
if (!Value.empty())
OS << ": " << Value;
OS << "(" << Id << ")";
}
static void printTree(raw_ostream &OS, diff::SyntaxTree &Tree) {
for (diff::NodeId Id : Tree) {
for (int I = 0; I < Tree.getNode(Id).Depth; ++I)
OS << " ";
printNode(OS, Tree, Id);
OS << "\n";
}
}
static void printDstChange(raw_ostream &OS, diff::ASTDiff &Diff,
diff::SyntaxTree &SrcTree, diff::SyntaxTree &DstTree,
diff::NodeId Dst) {
const diff::Node &DstNode = DstTree.getNode(Dst);
diff::NodeId Src = Diff.getMapped(DstTree, Dst);
switch (DstNode.Change) {
case diff::None:
break;
case diff::Delete:
llvm_unreachable("The destination tree can't have deletions.");
case diff::Update:
OS << "Update ";
printNode(OS, SrcTree, Src);
OS << " to " << DstTree.getNodeValue(Dst) << "\n";
break;
case diff::Insert:
case diff::Move:
case diff::UpdateMove:
if (DstNode.Change == diff::Insert)
OS << "Insert";
else if (DstNode.Change == diff::Move)
OS << "Move";
else if (DstNode.Change == diff::UpdateMove)
OS << "Update and Move";
OS << " ";
printNode(OS, DstTree, Dst);
OS << " into ";
printNode(OS, DstTree, DstNode.Parent);
OS << " at " << DstTree.findPositionInParent(Dst) << "\n";
break;
}
}
int main(int argc, const char **argv) {
std::string ErrorMessage;
std::unique_ptr<CompilationDatabase> CommonCompilations =
FixedCompilationDatabase::loadFromCommandLine(argc, argv, ErrorMessage);
if (!CommonCompilations && !ErrorMessage.empty())
llvm::errs() << ErrorMessage;
cl::HideUnrelatedOptions(ClangDiffCategory);
if (!cl::ParseCommandLineOptions(argc, argv)) {
cl::PrintOptionValues();
return 1;
}
addExtraArgs(CommonCompilations);
if (ASTDump || ASTDumpJson) {
if (!DestinationPath.empty()) {
llvm::errs() << "Error: Please specify exactly one filename.\n";
return 1;
}
std::unique_ptr<ASTUnit> AST = getAST(CommonCompilations, SourcePath);
if (!AST)
return 1;
diff::SyntaxTree Tree(AST->getASTContext());
if (ASTDump) {
printTree(llvm::outs(), Tree);
return 0;
}
llvm::outs() << R"({"filename":")";
printJsonString(llvm::outs(), SourcePath);
llvm::outs() << R"(","root":)";
printNodeAsJson(llvm::outs(), Tree, Tree.getRootId());
llvm::outs() << "}\n";
return 0;
}
if (DestinationPath.empty()) {
llvm::errs() << "Error: Exactly two paths are required.\n";
return 1;
}
std::unique_ptr<ASTUnit> Src = getAST(CommonCompilations, SourcePath);
std::unique_ptr<ASTUnit> Dst = getAST(CommonCompilations, DestinationPath);
if (!Src || !Dst)
return 1;
diff::ComparisonOptions Options;
if (MaxSize != -1)
Options.MaxSize = MaxSize;
if (!StopAfter.empty()) {
if (StopAfter == "topdown")
Options.StopAfterTopDown = true;
else if (StopAfter != "bottomup") {
llvm::errs() << "Error: Invalid argument for -stop-after\n";
return 1;
}
}
diff::SyntaxTree SrcTree(Src->getASTContext());
diff::SyntaxTree DstTree(Dst->getASTContext());
diff::ASTDiff Diff(SrcTree, DstTree, Options);
if (HtmlDiff) {
llvm::outs() << HtmlDiffHeader << "<pre>";
llvm::outs() << "<div id='L' class='code'>";
printHtmlForNode(llvm::outs(), Diff, SrcTree, true, SrcTree.getRootId(), 0);
llvm::outs() << "</div>";
llvm::outs() << "<div id='R' class='code'>";
printHtmlForNode(llvm::outs(), Diff, DstTree, false, DstTree.getRootId(),
0);
llvm::outs() << "</div>";
llvm::outs() << "</pre></div></body></html>\n";
return 0;
}
for (diff::NodeId Dst : DstTree) {
diff::NodeId Src = Diff.getMapped(DstTree, Dst);
if (PrintMatches && Src.isValid()) {
llvm::outs() << "Match ";
printNode(llvm::outs(), SrcTree, Src);
llvm::outs() << " to ";
printNode(llvm::outs(), DstTree, Dst);
llvm::outs() << "\n";
}
printDstChange(llvm::outs(), Diff, SrcTree, DstTree, Dst);
}
for (diff::NodeId Src : SrcTree) {
if (Diff.getMapped(SrcTree, Src).isInvalid()) {
llvm::outs() << "Delete ";
printNode(llvm::outs(), SrcTree, Src);
llvm::outs() << "\n";
}
}
return 0;
}