# Functions for copying sources to the Nix store. { lib }: # Tested in lib/tests/sources.sh let inherit (lib.strings) match split storeDir escapeRegex removePrefix ; inherit (lib) boolToString filter isString readFile concatStrings length elemAt isList any ; inherit (lib.filesystem) pathIsRegularFile ; /** A basic filter for `cleanSourceWith` that removes directories of version control system, backup files (`*~`) and some generated files. # Inputs `name` : 1\. Function argument `type` : 2\. Function argument */ cleanSourceFilter = name: type: let baseName = baseNameOf (toString name); in !( # Filter out version control software files/directories ( baseName == ".git" || type == "directory" && ( baseName == ".svn" || baseName == "CVS" || baseName == ".hg" || baseName == ".jj" || baseName == ".pijul" || baseName == "_darcs" ) ) || # Filter out editor backup / swap files. lib.hasSuffix "~" baseName || match "^\\.sw[a-z]$" baseName != null || match "^\\..*\\.sw[a-z]$" baseName != null || # Filter out generates files. lib.hasSuffix ".o" baseName || lib.hasSuffix ".so" baseName || # Filter out nix-build result symlinks (type == "symlink" && lib.hasPrefix "result" baseName) || # Filter out sockets and other types of files we can't have in the store. (type == "unknown") ); /** Filters a source tree removing version control files and directories using `cleanSourceFilter`. # Inputs `src` : 1\. Function argument # Examples :::{.example} ## `cleanSource` usage example ```nix cleanSource ./. ``` ::: */ cleanSource = src: cleanSourceWith { filter = cleanSourceFilter; inherit src; }; /** Like `builtins.filterSource`, except it will compose with itself, allowing you to chain multiple calls together without any intermediate copies being put in the nix store. # Examples :::{.example} ## `cleanSourceWith` usage example ```nix lib.cleanSourceWith { filter = f; src = lib.cleanSourceWith { filter = g; src = ./.; }; } # Succeeds! builtins.filterSource f (builtins.filterSource g ./.) # Fails! ``` ::: */ cleanSourceWith = { # A path or cleanSourceWith result to filter and/or rename. src, # Optional with default value: constant true (include everything) # The function will be combined with the && operator such # that src.filter is called lazily. # For implementing a filter, see # https://nixos.org/nix/manual/#builtin-filterSource # Type: A function (Path -> Type -> Bool) filter ? _path: _type: true, # Optional name to use as part of the store path. # This defaults to `src.name` or otherwise `"source"`. name ? null, }: let orig = toSourceAttributes src; in fromSourceAttributes { inherit (orig) origSrc; filter = path: type: filter path type && orig.filter path type; name = if name != null then name else orig.name; }; /** Add logging to a source, for troubleshooting the filtering behavior. # Inputs `src` : Source to debug. The returned source will behave like this source, but also log its filter invocations. # Type ``` sources.trace :: SourceLike -> Source ``` */ trace = # Source to debug. The returned source will behave like this source, but also log its filter invocations. src: let attrs = toSourceAttributes src; in fromSourceAttributes ( attrs // { filter = path: type: let r = attrs.filter path type; in builtins.trace "${attrs.name}.filter ${path} = ${boolToString r}" r; } ) // { satisfiesSubpathInvariant = src ? satisfiesSubpathInvariant && src.satisfiesSubpathInvariant; }; /** Filter sources by a list of regular expressions. # Inputs `src` : 1\. Function argument `regexes` : 2\. Function argument # Examples :::{.example} ## `sourceByRegex` usage example ```nix src = sourceByRegex ./my-subproject [".*\\.py$" "^database\\.sql$"] ``` ::: */ sourceByRegex = src: regexes: let isFiltered = src ? _isLibCleanSourceWith; origSrc = if isFiltered then src.origSrc else src; in lib.cleanSourceWith { filter = ( path: type: let relPath = lib.removePrefix (toString origSrc + "/") (toString path); in lib.any (re: match re relPath != null) regexes ); inherit src; }; /** Get all files ending with the specified suffices from the given source directory or its descendants, omitting files that do not match any suffix. The result of the example below will include files like `./dir/module.c` and `./dir/subdir/doc.xml` if present. # Inputs `src` : Path or source containing the files to be returned `exts` : A list of file suffix strings # Type ``` sourceFilesBySuffices :: SourceLike -> [String] -> Source ``` # Examples :::{.example} ## `sourceFilesBySuffices` usage example ```nix sourceFilesBySuffices ./. [ ".xml" ".c" ] ``` ::: */ sourceFilesBySuffices = # Path or source containing the files to be returned src: # A list of file suffix strings exts: let filter = name: type: let base = baseNameOf (toString name); in type == "directory" || lib.any (ext: lib.hasSuffix ext base) exts; in cleanSourceWith { inherit filter src; }; pathIsGitRepo = path: (_commitIdFromGitRepoOrError path) ? value; /** Get the commit id of a git repo. # Inputs `path` : 1\. Function argument # Examples :::{.example} ## `commitIdFromGitRepo` usage example ```nix commitIdFromGitRepo ``` ::: */ commitIdFromGitRepo = path: let commitIdOrError = _commitIdFromGitRepoOrError path; in commitIdOrError.value or (throw commitIdOrError.error); # Get the commit id of a git repo. # Returns `{ value = commitHash }` or `{ error = "... message ..." }`. # Example: commitIdFromGitRepo # not exported, used for commitIdFromGitRepo _commitIdFromGitRepoOrError = let readCommitFromFile = file: path: let fileName = path + "/${file}"; packedRefsName = path + "/packed-refs"; absolutePath = base: path: if lib.hasPrefix "/" path then path else if lib.hasPrefix "/" base then "${base}/${path}" else "/${base}/${path}"; in if pathIsRegularFile path # Resolve git worktrees. See gitrepository-layout(5) then let m = match "^gitdir: (.*)$" (lib.fileContents path); in if m == null then { error = "File contains no gitdir reference: " + path; } else let gitDir = absolutePath (dirOf path) (lib.head m); commonDir'' = if pathIsRegularFile "${gitDir}/commondir" then lib.fileContents "${gitDir}/commondir" else gitDir; commonDir' = lib.removeSuffix "/" commonDir''; commonDir = absolutePath gitDir commonDir'; refFile = lib.removePrefix "${commonDir}/" "${gitDir}/${file}"; in readCommitFromFile refFile commonDir else if pathIsRegularFile fileName # Sometimes git stores the commitId directly in the file but # sometimes it stores something like: «ref: refs/heads/branch-name» then let fileContent = lib.fileContents fileName; matchRef = match "^ref: (.*)$" fileContent; in if matchRef == null then { value = fileContent; } else readCommitFromFile (lib.head matchRef) path else if pathIsRegularFile packedRefsName # Sometimes, the file isn't there at all and has been packed away in the # packed-refs file, so we have to grep through it: then let fileContent = readFile packedRefsName; matchRef = match "([a-z0-9]+) ${file}"; isRef = s: isString s && (matchRef s) != null; # there is a bug in libstdc++ leading to stackoverflow for long strings: # https://github.com/NixOS/nix/issues/2147#issuecomment-659868795 refs = filter isRef (split "\n" fileContent); in if refs == [ ] then { error = "Could not find " + file + " in " + packedRefsName; } else { value = lib.head (matchRef (lib.head refs)); } else { error = "Not a .git directory: " + toString path; }; in readCommitFromFile "HEAD"; pathHasContext = builtins.hasContext or (lib.hasPrefix storeDir); canCleanSource = src: src ? _isLibCleanSourceWith || !(pathHasContext (toString src)); # -------------------------------------------------------------------------- # # Internal functions # # toSourceAttributes : sourceLike -> SourceAttrs # # Convert any source-like object into a simple, singular representation. # We don't expose this representation in order to avoid having a fifth path- # like class of objects in the wild. # (Existing ones being: paths, strings, sources and x//{outPath}) # So instead of exposing internals, we build a library of combinator functions. toSourceAttributes = src: let isFiltered = src ? _isLibCleanSourceWith; in { # The original path origSrc = if isFiltered then src.origSrc else src; filter = if isFiltered then src.filter else _: _: true; name = if isFiltered then src.name else "source"; }; # fromSourceAttributes : SourceAttrs -> Source # # Inverse of toSourceAttributes for Source objects. fromSourceAttributes = { origSrc, filter, name, }: { _isLibCleanSourceWith = true; inherit origSrc filter name; outPath = builtins.path { inherit filter name; path = origSrc; }; }; # urlToName : (URL | Path | String) -> String # # Transform a URL (or path, or string) into a clean package name. urlToName = url: let inherit (lib.strings) stringLength; base = baseNameOf (lib.removeSuffix "/" (lib.last (lib.splitString ":" (toString url)))); # chop away one git or archive-related extension removeExt = name: let matchExt = match "(.*)\\.(git|tar|zip|gz|tgz|bz|tbz|bz2|tbz2|lzma|txz|xz|zstd)$" name; in if matchExt != null then lib.head matchExt else name; # apply function f to string x while the result shrinks shrink = f: x: let v = f x; in if stringLength v < stringLength x then shrink f v else x; in shrink removeExt base; # shortRev : (String | Integer) -> String # # Given a package revision (like "refs/tags/v12.0"), produce a short revision ("12.0"). shortRev = rev: let baseRev = baseNameOf (toString rev); matchHash = match "[a-f0-9]+" baseRev; matchVer = match "([A-Za-z]+[-_. ]?)*(v)?([0-9.]+.*)" baseRev; in if matchHash != null then builtins.substring 0 7 baseRev else if matchVer != null then lib.last matchVer else baseRev; # revOrTag : String -> String -> String # # Turn git `rev` and `tag` pair into a revision usable in `repoRevToName*`. revOrTag = rev: tag: if tag != null then tag else if rev != null then rev else "HEAD"; # repoRevToNameFull : (URL | Path | String) -> (String | Integer | null) -> (String | null) -> String # # See `repoRevToName` below. repoRevToNameFull = repo_: rev_: suffix_: let repo = urlToName repo_; rev = if rev_ != null then "-${shortRev rev_}" else ""; suffix = if suffix_ != null then "-${suffix_}" else ""; in "${repo}${rev}${suffix}-source"; # repoRevToName : String -> (URL | Path | String) -> (String | Integer | null) -> String -> String # # Produce derivation.name attribute for a given repository URL/path/name and (optionally) its revision/version tag. # # This is used by fetch(zip|git|FromGitHub|hg|svn|etc) to generate discoverable # /nix/store paths. # # This uses a different implementation depending on the `pretty` argument: # "source" -> name everything as "source" # "versioned" -> name everything as "${repo}-${rev}-source" # "full" -> name everything as "${repo}-${rev}-${fetcher}-source" repoRevToName = kind: # match on `kind` first to minimize the thunk if kind == "source" then ( repo: rev: suffix: "source" ) else if kind == "versioned" then ( repo: rev: suffix: repoRevToNameFull repo rev null ) else if kind == "full" then repoRevToNameFull else throw "repoRevToName: invalid kind"; /** Filter a source tree by a list of doublestar-style glob patterns, returning a source that only contains paths matching at least one pattern. `*` matches a single path component, and `**` matches any number of components. # Inputs `src` : The source tree to filter. `patterns` : List of glob patterns to include, e.g. `[ "*.py" "src/**" ]`. A leading `**` (e.g. `**\/*.py` for all `.py` files at any depth) is also supported; the `\` here is just a Nix string escape used to avoid closing this comment. # Examples :::{.example} ## `sourceByGlobs` usage example - Include everything under a subdirectory ```nix src = sourceByGlobs ./. [ "src/**" "tests/**" ] ``` - Include all .py files in root directory only ```nix src = sourceByGlobs ./. [ "*.py" ] ``` ::: */ sourceByGlobs = let splitPath = path: filter isString (split "/" path); # Make component regex mkRe = s: if s == "**" then ".*" # Has special handling below else concatStrings (map (tok: if isList tok then "[^/]*" else escapeRegex tok) (split "\\*+" s)); # Make a source filter function from pattern mkMatcher = pat: let globs = map mkRe (splitPath pat); glen = length globs; in path: type: let path' = splitPath path; plen = length path'; recurse = gi: pi: let g = elemAt globs gi; p = elemAt path' pi; m = match g p != null; in if pi >= plen then # Reached end of path gi >= glen || (type == "directory" || type == "symlink") # Only allow partial matches for directories else if gi >= glen then # Reached end of globs false else if g == ".*" then # Special handling for ** ( # Lookahead for next glob match if (gi + 1) == glen then true else if (match (elemAt globs (gi + 1)) p != null) then recurse (gi + 1) pi else if m then recurse gi (pi + 1) else false ) else if m then recurse (gi + 1) (pi + 1) else false; in recurse 0 0; mkSourceFilter = root: patterns: let root' = "${toString root}/"; matchers = map mkMatcher patterns; in name: type: let name' = removePrefix root' name; in any (m: m name' type) matchers; in src: patterns: lib.cleanSourceWith { filter = mkSourceFilter src patterns; inherit src; }; in { inherit pathIsGitRepo commitIdFromGitRepo cleanSource cleanSourceWith cleanSourceFilter pathHasContext canCleanSource urlToName shortRev revOrTag repoRevToName sourceByRegex sourceFilesBySuffices sourceByGlobs trace ; inherit (builtins) filterSource; }