diff --git a/guix/import/utils.scm b/guix/import/utils.scm index 4694b6e7ef..bdce902d87 100644 --- a/guix/import/utils.scm +++ b/guix/import/utils.scm @@ -34,12 +34,14 @@ #:use-module (guix gexp) #:use-module (guix store) #:use-module (guix download) + #:use-module (guix sets) #:use-module (gnu packages) #:use-module (ice-9 match) #:use-module (ice-9 rdelim) #:use-module (ice-9 receive) #:use-module (ice-9 regex) #:use-module (srfi srfi-1) + #:use-module (srfi srfi-9) #:use-module (srfi srfi-11) #:use-module (srfi srfi-26) #:use-module (srfi srfi-41) @@ -377,40 +379,51 @@ separated by PRED." (chr (char-downcase chr))) name))) +(define (topological-sort nodes + node-dependencies + node-name) + "Perform a breadth-first traversal of the graph rooted at NODES, a list of +nodes, and return the list of nodes sorted in topological order. Call +NODE-DEPENDENCIES to obtain the dependencies of a node, and NODE-NAME to +obtain a node's uniquely identifying \"key\"." + (let loop ((nodes nodes) + (result '()) + (visited (set))) + (match nodes + (() + (reverse result)) + ((head . tail) + (if (set-contains? visited (node-name head)) + (loop tail result visited) + (let ((dependencies (node-dependencies head))) + (loop (append dependencies tail) + (cons head result) + (set-insert (node-name head) visited)))))))) + (define* (recursive-import package-name repo #:key repo->guix-package guix-name #:allow-other-keys) "Generate a stream of package expressions for PACKAGE-NAME and all its dependencies." - (define (exists? dependency) - (not (null? (find-packages-by-name (guix-name dependency))))) - (define initial-state (list #f (list package-name) (list))) - (define (step state) - (match state - ((prev (next . rest) done) - (define (handle? dep) - (and - (not (equal? dep next)) - (not (member dep done)) - (not (exists? dep)))) - (receive (package . dependencies) (repo->guix-package next repo) - (list - (if package package '()) ;; default #f on failure would interrupt - (if package - (lset-union equal? rest (filter handle? (car dependencies))) - rest) - (cons next done)))) - ((prev '() done) - (list #f '() done)))) + (define-record-type + (make-node name package dependencies) + node? + (name node-name) + (package node-package) + (dependencies node-dependencies)) - ;; Generate a lazy stream of package expressions for all unknown - ;; dependencies in the graph. - (stream-unfold - ;; map: produce a stream element - (match-lambda ((latest queue done) latest)) - ;; predicate - (match-lambda ((latest queue done) latest)) - ;; generator: update the queue - step - ;; initial state - (step initial-state))) + (define (exists? name) + (not (null? (find-packages-by-name (guix-name name))))) + + (define (lookup-node name) + (receive (package dependencies) (repo->guix-package name repo) + (make-node name package dependencies))) + + (list->stream ;TODO: remove streams + (map node-package + (topological-sort (list (lookup-node package-name)) + (lambda (node) + (map lookup-node + (remove exists? + (node-dependencies node)))) + node-name))))