llvm-project/clang-tools-extra/clangd/SemanticHighlighting.h

122 lines
4.2 KiB
C++

//==-- SemanticHighlighting.h - Generating highlights from the AST-- 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 supports semantic highlighting: categorizing tokens in the file so
// that the editor can color/style them differently.
//
// This is particularly valuable for C++: its complex and context-dependent
// grammar is a challenge for simple syntax-highlighting techniques.
//
// We support two protocols for providing highlights to the client:
// - the `textDocument/semanticTokens` request from LSP 3.16
// https://github.com/microsoft/vscode-languageserver-node/blob/release/protocol/3.16.0-next.1/protocol/src/protocol.semanticTokens.proposed.ts
// - the earlier proposed `textDocument/semanticHighlighting` notification
// https://github.com/microsoft/vscode-languageserver-node/pull/367
// This is referred to as "Theia" semantic highlighting in the code.
// It was supported from clangd 9 but should be considered deprecated as of
// clangd 11 and eventually removed.
//
// Semantic highlightings are calculated for an AST by visiting every AST node
// and classifying nodes that are interesting to highlight (variables/function
// calls etc.).
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_CLANG_TOOLS_EXTRA_CLANGD_SEMANTICHIGHLIGHTING_H
#define LLVM_CLANG_TOOLS_EXTRA_CLANGD_SEMANTICHIGHLIGHTING_H
#include "Protocol.h"
#include "llvm/Support/raw_ostream.h"
namespace clang {
namespace clangd {
class ParsedAST;
enum class HighlightingKind {
Variable = 0,
LocalVariable,
Parameter,
Function,
Method,
StaticMethod,
Field,
StaticField,
Class,
Enum,
EnumConstant,
Typedef,
DependentType,
DependentName,
Namespace,
TemplateParameter,
Concept,
Primitive,
Macro,
// This one is different from the other kinds as it's a line style
// rather than a token style.
InactiveCode,
LastKind = InactiveCode
};
llvm::raw_ostream &operator<<(llvm::raw_ostream &OS, HighlightingKind K);
// Contains all information needed for the highlighting a token.
struct HighlightingToken {
HighlightingKind Kind;
Range R;
};
bool operator==(const HighlightingToken &L, const HighlightingToken &R);
bool operator<(const HighlightingToken &L, const HighlightingToken &R);
/// Contains all information about highlightings on a single line.
struct LineHighlightings {
int Line;
std::vector<HighlightingToken> Tokens;
bool IsInactive;
};
bool operator==(const LineHighlightings &L, const LineHighlightings &R);
// Returns all HighlightingTokens from an AST. Only generates highlights for the
// main AST.
std::vector<HighlightingToken> getSemanticHighlightings(ParsedAST &AST);
std::vector<SemanticToken> toSemanticTokens(llvm::ArrayRef<HighlightingToken>);
llvm::StringRef toSemanticTokenType(HighlightingKind Kind);
std::vector<SemanticTokensEdit> diffTokens(llvm::ArrayRef<SemanticToken> Before,
llvm::ArrayRef<SemanticToken> After);
/// Converts a HighlightingKind to a corresponding TextMate scope
/// (https://manual.macromates.com/en/language_grammars).
llvm::StringRef toTextMateScope(HighlightingKind Kind);
/// Convert to LSP's semantic highlighting information.
std::vector<TheiaSemanticHighlightingInformation>
toTheiaSemanticHighlightingInformation(
llvm::ArrayRef<LineHighlightings> Tokens);
/// Return a line-by-line diff between two highlightings.
/// - if the tokens on a line are the same in both highlightings, this line is
/// omitted.
/// - if a line exists in New but not in Old, the tokens on this line are
/// emitted.
/// - if a line does not exist in New but exists in Old, an empty line is
/// emitted (to tell client to clear the previous highlightings on this line).
///
/// REQUIRED: Old and New are sorted.
std::vector<LineHighlightings>
diffHighlightings(ArrayRef<HighlightingToken> New,
ArrayRef<HighlightingToken> Old);
} // namespace clangd
} // namespace clang
#endif