llvm-project/clang-tools-extra/clangd/support/Markup.h

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4.4 KiB
C++

//===--- Markup.h -------------------------------------------*- 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
//
//===----------------------------------------------------------------------===//
//
// A model of formatted text that can be rendered to plaintext or markdown.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_CLANG_TOOLS_EXTRA_CLANGD_SUPPORT_MARKUP_H
#define LLVM_CLANG_TOOLS_EXTRA_CLANGD_SUPPORT_MARKUP_H
#include "llvm/Support/raw_ostream.h"
#include <cstddef>
#include <memory>
#include <string>
#include <vector>
namespace clang {
namespace clangd {
namespace markup {
/// Holds text and knows how to lay it out. Multiple blocks can be grouped to
/// form a document. Blocks include their own trailing newlines, container
/// should trim them if need be.
class Block {
public:
virtual void renderMarkdown(llvm::raw_ostream &OS) const = 0;
virtual void renderPlainText(llvm::raw_ostream &OS) const = 0;
virtual std::unique_ptr<Block> clone() const = 0;
std::string asMarkdown() const;
std::string asPlainText() const;
virtual bool isRuler() const { return false; }
virtual ~Block() = default;
};
/// Represents parts of the markup that can contain strings, like inline code,
/// code block or plain text.
/// One must introduce different paragraphs to create separate blocks.
class Paragraph : public Block {
public:
void renderMarkdown(llvm::raw_ostream &OS) const override;
void renderPlainText(llvm::raw_ostream &OS) const override;
std::unique_ptr<Block> clone() const override;
/// Append plain text to the end of the string.
Paragraph &appendText(llvm::StringRef Text);
/// Append inline code, this translates to the ` block in markdown.
/// \p Preserve indicates the code span must be apparent even in plaintext.
Paragraph &appendCode(llvm::StringRef Code, bool Preserve = false);
/// Ensure there is space between the surrounding chunks.
/// Has no effect at the beginning or end of a paragraph.
Paragraph &appendSpace();
private:
struct Chunk {
enum {
PlainText,
InlineCode,
} Kind = PlainText;
// Preserve chunk markers in plaintext.
bool Preserve = false;
std::string Contents;
// Whether this chunk should be surrounded by whitespace.
// Consecutive SpaceAfter and SpaceBefore will be collapsed into one space.
// Code spans don't usually set this: their spaces belong "inside" the span.
bool SpaceBefore = false;
bool SpaceAfter = false;
};
std::vector<Chunk> Chunks;
};
/// Represents a sequence of one or more documents. Knows how to print them in a
/// list like format, e.g. by prepending with "- " and indentation.
class BulletList : public Block {
public:
void renderMarkdown(llvm::raw_ostream &OS) const override;
void renderPlainText(llvm::raw_ostream &OS) const override;
std::unique_ptr<Block> clone() const override;
class Document &addItem();
private:
std::vector<class Document> Items;
};
/// A format-agnostic representation for structured text. Allows rendering into
/// markdown and plaintext.
class Document {
public:
Document() = default;
Document(const Document &Other) { *this = Other; }
Document &operator=(const Document &);
Document(Document &&) = default;
Document &operator=(Document &&) = default;
void append(Document Other);
/// Adds a semantical block that will be separate from others.
Paragraph &addParagraph();
/// Inserts a horizontal separator to the document.
void addRuler();
/// Adds a block of code. This translates to a ``` block in markdown. In plain
/// text representation, the code block will be surrounded by newlines.
void addCodeBlock(std::string Code, std::string Language = "cpp");
/// Heading is a special type of paragraph that will be prepended with \p
/// Level many '#'s in markdown.
Paragraph &addHeading(size_t Level);
BulletList &addBulletList();
/// Doesn't contain any trailing newlines.
/// We try to make the markdown human-readable, e.g. avoid extra escaping.
/// At least one client (coc.nvim) displays the markdown verbatim!
std::string asMarkdown() const;
/// Doesn't contain any trailing newlines.
std::string asPlainText() const;
private:
std::vector<std::unique_ptr<Block>> Children;
};
} // namespace markup
} // namespace clangd
} // namespace clang
#endif