diff options
| -rw-r--r-- | doc/guix.texi | 48 | ||||
| -rw-r--r-- | guix/scripts/graph.scm | 46 | ||||
| -rw-r--r-- | tests/guix-graph.sh | 16 |
3 files changed, 102 insertions, 8 deletions
diff --git a/doc/guix.texi b/doc/guix.texi index 8d38601201..996d045aa3 100644 --- a/doc/guix.texi +++ b/doc/guix.texi @@ -10021,6 +10021,12 @@ In this example we see that the combination of the four packages takes 102.3@tie{}MiB in total, which is much less than the sum of each closure since they have a lot of dependencies in common. +When looking at the profile returned by @command{guix size}, you may +find yourself wondering why a given package shows up in the profile at +all. To understand it, you can use @command{guix graph --path -t +references} to display the shortest path between the two packages +(@pxref{Invoking guix graph}). + The available options are: @table @option @@ -10081,8 +10087,9 @@ directly to the @command{dot} command of Graphviz. It can also emit an HTML page with embedded JavaScript code to display a ``chord diagram'' in a Web browser, using the @uref{https://d3js.org/, d3.js} library, or emit Cypher queries to construct a graph in a graph database supporting -the @uref{https://www.opencypher.org/, openCypher} query language. -The general syntax is: +the @uref{https://www.opencypher.org/, openCypher} query language. With +@option{--path}, it simply displays the shortest path between two +packages. The general syntax is: @example guix graph @var{options} @var{package}@dots{} @@ -10235,6 +10242,29 @@ collected. @end table +@cindex shortest path, between packages +Often, the graph of the package you are interested in does not fit on +your screen, and anyway all you want to know is @emph{why} that package +actually depends on some seemingly unrelated package. The +@option{--path} option instructs @command{guix graph} to display the +shortest path between two packages (or derivations, or store items, +etc.): + +@example +$ guix graph --path emacs libunistring +emacs@@26.3 +mailutils@@3.9 +libunistring@@0.9.10 +$ guix graph --path -t derivation emacs libunistring +/gnu/store/@dots{}-emacs-26.3.drv +/gnu/store/@dots{}-mailutils-3.9.drv +/gnu/store/@dots{}-libunistring-0.9.10.drv +$ guix graph --path -t references emacs libunistring +/gnu/store/@dots{}-emacs-26.3 +/gnu/store/@dots{}-libidn2-2.2.0 +/gnu/store/@dots{}-libunistring-0.9.10 +@end example + The available options are the following: @table @option @@ -10255,6 +10285,20 @@ List the supported graph backends. Currently, the available backends are Graphviz and d3.js. +@item --path +Display the shortest path between two nodes of the type specified by +@option{--type}. The example below shows the shortest path between +@code{libreoffice} and @code{llvm} according to the references of +@code{libreoffice}: + +@example +$ guix graph --path -t references libreoffice llvm +/gnu/store/@dots{}-libreoffice-6.4.2.2 +/gnu/store/@dots{}-libepoxy-1.5.4 +/gnu/store/@dots{}-mesa-19.3.4 +/gnu/store/@dots{}-llvm-9.0.1 +@end example + @item --expression=@var{expr} @itemx -e @var{expr} Consider the package @var{expr} evaluates to. diff --git a/guix/scripts/graph.scm b/guix/scripts/graph.scm index d69dace14f..1d5db3b3cb 100644 --- a/guix/scripts/graph.scm +++ b/guix/scripts/graph.scm @@ -457,6 +457,29 @@ package modules, while attempting to retain user package modules." ;;; +;;; Displaying a path. +;;; + +(define (display-path node1 node2 type) + "Display the shortest path from NODE1 to NODE2, of TYPE." + (mlet %store-monad ((path (shortest-path node1 node2 type))) + (define node-label + (let ((label (node-type-label type))) + ;; Special-case derivations and store items to print them in full, + ;; contrary to what their 'node-type-label' normally does. + (match-lambda + ((? derivation? drv) (derivation-file-name drv)) + ((? string? str) str) + (node (label node))))) + + (if path + (format #t "~{~a~%~}" (map node-label path)) + (leave (G_ "no path from '~a' to '~a'~%") + (node-label node1) (node-label node2))) + (return #t))) + + +;;; ;;; Command-line options. ;;; @@ -465,6 +488,9 @@ package modules, while attempting to retain user package modules." (lambda (opt name arg result) (alist-cons 'node-type (lookup-node-type arg) result))) + (option '("path") #f #f + (lambda (opt name arg result) + (alist-cons 'path? #t result))) (option '("list-types") #f #f (lambda (opt name arg result) (list-node-types) @@ -511,6 +537,8 @@ Emit a representation of the dependency graph of PACKAGE...\n")) (display (G_ " --list-types list the available graph types")) (display (G_ " + --path display the shortest path between the given nodes")) + (display (G_ " -e, --expression=EXPR consider the package EXPR evaluates to")) (display (G_ " -s, --system=SYSTEM consider the graph for SYSTEM--e.g., \"i686-linux\"")) @@ -566,11 +594,19 @@ Emit a representation of the dependency graph of PACKAGE...\n")) (mlet %store-monad ((_ (set-grafting #f)) (nodes (mapm %store-monad (node-type-convert type) - items))) - (export-graph (concatenate nodes) - (current-output-port) - #:node-type type - #:backend backend)) + (reverse items)))) + (if (assoc-ref opts 'path?) + (match nodes + (((node1 _ ...) (node2 _ ...)) + (display-path node1 node2 type)) + (_ + (leave (G_ "'--path' option requires exactly two \ +nodes (given ~a)~%") + (length nodes)))) + (export-graph (concatenate nodes) + (current-output-port) + #:node-type type + #:backend backend))) #:system (assq-ref opts 'system))))) #t) diff --git a/tests/guix-graph.sh b/tests/guix-graph.sh index 4c37b61b38..ccb4933c88 100644 --- a/tests/guix-graph.sh +++ b/tests/guix-graph.sh @@ -1,5 +1,5 @@ # GNU Guix --- Functional package management for GNU -# Copyright © 2015, 2016, 2019 Ludovic Courtès <ludo@gnu.org> +# Copyright © 2015, 2016, 2019, 2020 Ludovic Courtès <ludo@gnu.org> # Copyright © 2019 Simon Tournier <zimon.toutoune@gmail.com> # # This file is part of GNU Guix. @@ -82,3 +82,17 @@ then false; else true; fi # Try --load-path guix graph -L $module_dir dummy | grep 'label = "dummy' + +# Displaying shortest paths (or lack thereof). +if guix graph --path emacs vim; then false; else true; fi + +path="\ +emacs +gnutls +guile +libffi" +test "`guix graph --path emacs libffi | cut -d '@' -f1`" = "$path" + +# At the derivation level, there's a direct path because libffi is propagated +# via gtk+. +test "`guix graph --path -t derivation emacs libffi | wc -l`" -ge 2 |