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

137 lines
5.3 KiB
C++

//===--- URI.h - File URIs with schemes --------------------------*- 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
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_CLANG_TOOLS_EXTRA_CLANGD_URI_H
#define LLVM_CLANG_TOOLS_EXTRA_CLANGD_URI_H
#include "llvm/ADT/StringRef.h"
#include "llvm/Support/Error.h"
#include "llvm/Support/Registry.h"
namespace clang {
namespace clangd {
/// A URI describes the location of a source file.
/// In the simplest case, this is a "file" URI that directly encodes the
/// absolute path to a file. More abstract cases are possible: a shared index
/// service might expose repo:// URIs that are relative to the source control
/// root.
///
/// Clangd handles URIs of the form <scheme>:[//<authority>]<body>. It doesn't
/// further split the authority or body into constituent parts (e.g. query
/// strings is included in the body).
class URI {
public:
URI(llvm::StringRef Scheme, llvm::StringRef Authority, llvm::StringRef Body);
/// Returns decoded scheme e.g. "https"
llvm::StringRef scheme() const { return Scheme; }
/// Returns decoded authority e.g. "reviews.lvm.org"
llvm::StringRef authority() const { return Authority; }
/// Returns decoded body e.g. "/D41946"
llvm::StringRef body() const { return Body; }
/// Returns a string URI with all components percent-encoded.
std::string toString() const;
/// Creates a URI for a file in the given scheme. \p Scheme must be
/// registered. The URI is percent-encoded.
static llvm::Expected<URI> create(llvm::StringRef AbsolutePath,
llvm::StringRef Scheme);
// Similar to above except this picks a registered scheme that works. If none
// works, this falls back to "file" scheme.
static URI create(llvm::StringRef AbsolutePath);
/// This creates a file:// URI for \p AbsolutePath. The path must be absolute.
static URI createFile(llvm::StringRef AbsolutePath);
/// Parse a URI string "<scheme>:[//<authority>/]<path>". Percent-encoded
/// characters in the URI will be decoded.
static llvm::Expected<URI> parse(llvm::StringRef Uri);
/// Resolves the absolute path of \p U. If there is no matching scheme, or the
/// URI is invalid in the scheme, this returns an error.
///
/// \p HintPath A related path, such as the current file or working directory,
/// which can help disambiguate when the same file exists in many workspaces.
static llvm::Expected<std::string> resolve(const URI &U,
llvm::StringRef HintPath = "");
/// Same as above, in addition it parses the \p FileURI using URI::parse.
static llvm::Expected<std::string> resolve(llvm::StringRef FileURI,
llvm::StringRef HintPath = "");
/// Resolves \p AbsPath into a canonical path of its URI, by converting
/// \p AbsPath to URI and resolving the URI to get th canonical path.
/// This ensures that paths with the same URI are resolved into consistent
/// file path.
static llvm::Expected<std::string> resolvePath(llvm::StringRef AbsPath,
llvm::StringRef HintPath = "");
/// Gets the preferred spelling of this file for #include, if there is one,
/// e.g. <system_header.h>, "path/to/x.h".
///
/// This allows URI schemas to provide their customized include paths.
///
/// Returns an empty string if normal include-shortening based on the absolute
/// path should be used.
/// Fails if the URI is not valid in the schema.
static llvm::Expected<std::string> includeSpelling(const URI &U);
friend bool operator==(const URI &LHS, const URI &RHS) {
return std::tie(LHS.Scheme, LHS.Authority, LHS.Body) ==
std::tie(RHS.Scheme, RHS.Authority, RHS.Body);
}
friend bool operator<(const URI &LHS, const URI &RHS) {
return std::tie(LHS.Scheme, LHS.Authority, LHS.Body) <
std::tie(RHS.Scheme, RHS.Authority, RHS.Body);
}
private:
URI() = default;
std::string Scheme;
std::string Authority;
std::string Body;
};
/// URIScheme is an extension point for teaching clangd to recognize a custom
/// URI scheme. This is expected to be implemented and exposed via the
/// URISchemeRegistry.
class URIScheme {
public:
virtual ~URIScheme() = default;
/// Returns the absolute path of the file corresponding to the URI
/// authority+body in the file system. See URI::resolve for semantics of
/// \p HintPath.
virtual llvm::Expected<std::string>
getAbsolutePath(llvm::StringRef Authority, llvm::StringRef Body,
llvm::StringRef HintPath) const = 0;
virtual llvm::Expected<URI>
uriFromAbsolutePath(llvm::StringRef AbsolutePath) const = 0;
/// Returns the include path of the file (e.g. <path>, "path"), which can be
/// #included directly. See URI::includeSpelling for details.
virtual llvm::Expected<std::string> getIncludeSpelling(const URI &U) const {
return ""; // no customized include path for this scheme.
}
};
/// By default, a "file" scheme is supported where URI paths are always absolute
/// in the file system.
typedef llvm::Registry<URIScheme> URISchemeRegistry;
} // namespace clangd
} // namespace clang
#endif // LLVM_CLANG_TOOLS_EXTRA_CLANGD_URI_H