Nix/src/libexpr/flake/url-name.cc
Eelco Dolstra 936a364226 getNameFromURL(): Support uppercase characters in attribute names
In particular, this makes it handle 'legacyPackages' correctly.
2023-12-22 16:35:58 +01:00

49 lines
2 KiB
C++

#include "url-name.hh"
#include <regex>
#include <iostream>
namespace nix {
static const std::string attributeNamePattern("[a-zA-Z0-9_-]+");
static const std::regex lastAttributeRegex("(?:" + attributeNamePattern + "\\.)*(?!default)(" + attributeNamePattern +")(\\^.*)?");
static const std::string pathSegmentPattern("[a-zA-Z0-9_-]+");
static const std::regex lastPathSegmentRegex(".*/(" + pathSegmentPattern +")");
static const std::regex secondPathSegmentRegex("(?:" + pathSegmentPattern + ")/(" + pathSegmentPattern +")(?:/.*)?");
static const std::regex gitProviderRegex("github|gitlab|sourcehut");
static const std::regex gitSchemeRegex("git($|\\+.*)");
static const std::regex defaultOutputRegex(".*\\.default($|\\^.*)");
std::optional<std::string> getNameFromURL(const ParsedURL & url)
{
std::smatch match;
/* If there is a dir= argument, use its value */
if (url.query.count("dir") > 0)
return url.query.at("dir");
/* If the fragment isn't a "default" and contains two attribute elements, use the last one */
if (std::regex_match(url.fragment, match, lastAttributeRegex))
return match.str(1);
/* If this is a github/gitlab/sourcehut flake, use the repo name */
if (std::regex_match(url.scheme, gitProviderRegex) && std::regex_match(url.path, match, secondPathSegmentRegex))
return match.str(1);
/* If it is a regular git flake, use the directory name */
if (std::regex_match(url.scheme, gitSchemeRegex) && std::regex_match(url.path, match, lastPathSegmentRegex))
return match.str(1);
/* If everything failed but there is a non-default fragment, use it in full */
if (!url.fragment.empty() && !std::regex_match(url.fragment, defaultOutputRegex))
return url.fragment;
/* If there is no fragment, take the last element of the path */
if (std::regex_match(url.path, match, lastPathSegmentRegex))
return match.str(1);
/* If even that didn't work, the URL does not contain enough info to determine a useful name */
return {};
}
}