From e8113747e1abf7fa6225f7fcd31ca9e71e03cfbb Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Th=C3=A9ophane=20Hufschmitt?= Date: Thu, 20 Apr 2023 06:51:47 +0200 Subject: [PATCH] Split the parseFlakeRefWithFragment function Was starting to be very complex and hard to follow. Now the different cases should be easier to understand. --- src/libexpr/flake/flakeref.cc | 279 +++++++++++++++++++--------------- 1 file changed, 155 insertions(+), 124 deletions(-) diff --git a/src/libexpr/flake/flakeref.cc b/src/libexpr/flake/flakeref.cc index 2155c5f12..f7ef19b3f 100644 --- a/src/libexpr/flake/flakeref.cc +++ b/src/libexpr/flake/flakeref.cc @@ -69,127 +69,130 @@ std::optional maybeParseFlakeRef( } } -std::pair parseFlakeRefWithFragment( +std::pair parsePathFlakeRefWithFragment( const std::string & url, const std::optional & baseDir, bool allowMissing, bool isFlake) { - using namespace fetchers; + std::string path = url; + std::string fragment = ""; + std::map query; + auto pathEnd = url.find_first_of("#?"); + auto fragmentStart = pathEnd; + if (pathEnd != std::string::npos && url[pathEnd] == '?') { + fragmentStart = url.find("#"); + } + if (pathEnd != std::string::npos) { + path = url.substr(0, pathEnd); + } + if (fragmentStart != std::string::npos) { + fragment = percentDecode(url.substr(fragmentStart+1)); + } + if (pathEnd != std::string::npos && fragmentStart != std::string::npos) { + query = decodeQuery(url.substr(pathEnd+1, fragmentStart)); + } + + if (baseDir) { + /* Check if 'url' is a path (either absolute or relative + to 'baseDir'). If so, search upward to the root of the + repo (i.e. the directory containing .git). */ + + path = absPath(path, baseDir); + + if (isFlake) { + + if (!allowMissing && !pathExists(path + "/flake.nix")){ + notice("path '%s' does not contain a 'flake.nix', searching up",path); + + // Save device to detect filesystem boundary + dev_t device = lstat(path).st_dev; + bool found = false; + while (path != "/") { + if (pathExists(path + "/flake.nix")) { + found = true; + break; + } else if (pathExists(path + "/.git")) + throw Error("path '%s' is not part of a flake (neither it nor its parent directories contain a 'flake.nix' file)", path); + else { + if (lstat(path).st_dev != device) + throw Error("unable to find a flake before encountering filesystem boundary at '%s'", path); + } + path = dirOf(path); + } + if (!found) + throw BadURL("could not find a flake.nix file"); + } + + if (!S_ISDIR(lstat(path).st_mode)) + throw BadURL("path '%s' is not a flake (because it's not a directory)", path); + + if (!allowMissing && !pathExists(path + "/flake.nix")) + throw BadURL("path '%s' is not a flake (because it doesn't contain a 'flake.nix' file)", path); + + auto flakeRoot = path; + std::string subdir; + + while (flakeRoot != "/") { + if (pathExists(flakeRoot + "/.git")) { + auto base = std::string("git+file://") + flakeRoot; + + auto parsedURL = ParsedURL{ + .url = base, // FIXME + .base = base, + .scheme = "git+file", + .authority = "", + .path = flakeRoot, + .query = query, + }; + + if (subdir != "") { + if (parsedURL.query.count("dir")) + throw Error("flake URL '%s' has an inconsistent 'dir' parameter", url); + parsedURL.query.insert_or_assign("dir", subdir); + } + + if (pathExists(flakeRoot + "/.git/shallow")) + parsedURL.query.insert_or_assign("shallow", "1"); + + return std::make_pair( + FlakeRef(fetchers::Input::fromURL(parsedURL), getOr(parsedURL.query, "dir", "")), + fragment); + } + + subdir = std::string(baseNameOf(flakeRoot)) + (subdir.empty() ? "" : "/" + subdir); + flakeRoot = dirOf(flakeRoot); + } + } + + } else { + if (!hasPrefix(path, "/")) + throw BadURL("flake reference '%s' is not an absolute path", url); + path = canonPath(path + "/" + getOr(query, "dir", "")); + } + + fetchers::Attrs attrs; + attrs.insert_or_assign("type", "path"); + attrs.insert_or_assign("path", path); + + return std::make_pair(FlakeRef(fetchers::Input::fromAttrs(std::move(attrs)), ""), fragment); +}; + + +/* Check if 'url' is a flake ID. This is an abbreviated syntax for + 'flake:?ref=&rev='. */ +std::optional> parseFlakeIdRef( + const std::string & url, + bool isFlake +) +{ + std::smatch match; static std::regex flakeRegex( "((" + flakeIdRegexS + ")(?:/(?:" + refAndOrRevRegex + "))?)" + "(?:#(" + queryRegex + "))?", std::regex::ECMAScript); - std::smatch match; - - auto parsePathFlakeRef = [&]() { - std::string path = url; - std::string fragment = ""; - std::map query = {}; - auto pathEnd = url.find_first_of("#?"); - auto fragmentStart = pathEnd; - if (pathEnd != std::string::npos && url[pathEnd] == '?') - fragmentStart = url.find("#"); - if (pathEnd != std::string::npos) { - path = url.substr(0, pathEnd); - } - if (fragmentStart != std::string::npos) { - fragment = percentDecode(url.substr(fragmentStart+1)); - } - if (fragmentStart != std::string::npos && pathEnd != std::string::npos) { - query = decodeQuery(url.substr(pathEnd+1, fragmentStart)); - } - - if (baseDir) { - /* Check if 'url' is a path (either absolute or relative - to 'baseDir'). If so, search upward to the root of the - repo (i.e. the directory containing .git). */ - - path = absPath(path, baseDir); - - if (isFlake) { - - if (!allowMissing && !pathExists(path + "/flake.nix")){ - notice("path '%s' does not contain a 'flake.nix', searching up",path); - - // Save device to detect filesystem boundary - dev_t device = lstat(path).st_dev; - bool found = false; - while (path != "/") { - if (pathExists(path + "/flake.nix")) { - found = true; - break; - } else if (pathExists(path + "/.git")) - throw Error("path '%s' is not part of a flake (neither it nor its parent directories contain a 'flake.nix' file)", path); - else { - if (lstat(path).st_dev != device) - throw Error("unable to find a flake before encountering filesystem boundary at '%s'", path); - } - path = dirOf(path); - } - if (!found) - throw BadURL("could not find a flake.nix file"); - } - - if (!S_ISDIR(lstat(path).st_mode)) - throw BadURL("path '%s' is not a flake (because it's not a directory)", path); - - if (!allowMissing && !pathExists(path + "/flake.nix")) - throw BadURL("path '%s' is not a flake (because it doesn't contain a 'flake.nix' file)", path); - - auto flakeRoot = path; - std::string subdir; - - while (flakeRoot != "/") { - if (pathExists(flakeRoot + "/.git")) { - auto base = std::string("git+file://") + flakeRoot; - - auto parsedURL = ParsedURL{ - .url = base, // FIXME - .base = base, - .scheme = "git+file", - .authority = "", - .path = flakeRoot, - .query = query, - }; - - if (subdir != "") { - if (parsedURL.query.count("dir")) - throw Error("flake URL '%s' has an inconsistent 'dir' parameter", url); - parsedURL.query.insert_or_assign("dir", subdir); - } - - if (pathExists(flakeRoot + "/.git/shallow")) - parsedURL.query.insert_or_assign("shallow", "1"); - - return std::make_pair( - FlakeRef(Input::fromURL(parsedURL, isFlake), getOr(parsedURL.query, "dir", "")), - fragment); - } - - subdir = std::string(baseNameOf(flakeRoot)) + (subdir.empty() ? "" : "/" + subdir); - flakeRoot = dirOf(flakeRoot); - } - } - - } else { - if (!hasPrefix(path, "/")) - throw BadURL("flake reference '%s' is not an absolute path", url); - path = canonPath(path + "/" + getOr(query, "dir", "")); - } - - fetchers::Attrs attrs; - attrs.insert_or_assign("type", "path"); - attrs.insert_or_assign("path", path); - - return std::make_pair(FlakeRef(Input::fromAttrs(std::move(attrs)), ""), fragment); - }; - - /* Check if 'url' is a flake ID. This is an abbreviated syntax for - 'flake:?ref=&rev='. */ - if (std::regex_match(url, match, flakeRegex)) { auto parsedURL = ParsedURL{ .url = url, @@ -200,25 +203,53 @@ std::pair parseFlakeRefWithFragment( }; return std::make_pair( - FlakeRef(Input::fromURL(parsedURL), ""), + FlakeRef(fetchers::Input::fromURL(parsedURL, isFlake), ""), percentDecode(match.str(6))); } - else { - try { - auto parsedURL = parseURL(url); - std::string fragment; - std::swap(fragment, parsedURL.fragment); + return {}; +} - auto input = Input::fromURL(parsedURL, isFlake); - input.parent = baseDir; +std::optional> parseURLFlakeRef( + const std::string & url, + const std::optional & baseDir, + bool isFlake +) +{ + ParsedURL parsedURL; + try { + parsedURL = parseURL(url); + } catch (BadURL &) { + return std::nullopt; + } - return std::make_pair( - FlakeRef(std::move(input), getOr(parsedURL.query, "dir", "")), - fragment); - } catch (BadURL &) { - return parsePathFlakeRef(); - } + std::string fragment; + std::swap(fragment, parsedURL.fragment); + + auto input = fetchers::Input::fromURL(parsedURL, isFlake); + input.parent = baseDir; + + return std::make_pair( + FlakeRef(std::move(input), getOr(parsedURL.query, "dir", "")), + fragment); +} + +std::pair parseFlakeRefWithFragment( + const std::string & url, + const std::optional & baseDir, + bool allowMissing, + bool isFlake) +{ + using namespace fetchers; + + std::smatch match; + + if (auto res = parseFlakeIdRef(url, isFlake)) { + return *res; + } else if (auto res = parseURLFlakeRef(url, baseDir, isFlake)) { + return *res; + } else { + return parsePathFlakeRefWithFragment(url, baseDir, allowMissing, isFlake); } }