[PATCH RFC 4/4] DRAFT lint: Add 'input-labels' checker.

["Ludovic Courtès" <ludo@gnu.org>]

DRAFT: Good idea? If yes, add tests and doc.

* guix/lint.scm (check-input-labels): New procedure.
(%local-checkers): Add 'input-labels' checker.
---
 guix/lint.scm | 35 +++++++++++++++++++++++++++++++++++
 1 file changed, 35 insertions(+)

diff --git a/guix/lint.scm b/guix/lint.scm
index 1bebfe03d3..95f82dba60 100644
--- a/guix/lint.scm
+++ b/guix/lint.scm
@@ -383,6 +383,37 @@ of a package, and INPUT-NAMES, a list of package specifications such as
          (package-input-intersection (package-direct-inputs package)
                                      input-names))))
 
+(define (check-input-labels package)
+  "Emit a warning for labels that differ from the corresponding package name."
+  (define (check input-kind package-inputs)
+    (define (warning label name)
+      (make-warning package
+                    (G_ "label '~a' does not match package name '~a'")
+                    (list label name)
+                    #:field input-kind))
+
+    (append-map (match-lambda
+                  (((? string? label) (? package? dependency))
+                   (if (string=? label (package-name dependency))
+                       '()
+                       (list (warning label (package-name dependency)))))
+                  (((? string? label) (? package? dependency) output)
+                   (let ((expected (string-append (package-name dependency)
+                                                  ":" output)))
+                     (if (string=? label expected)
+                         '()
+                         (list (warning label expected)))))
+                  (_
+                   '()))
+                (package-inputs package)))
+
+  (append-map (match-lambda
+                ((kind proc)
+                 (check kind proc)))
+              `((native-inputs ,package-native-inputs)
+                (inputs ,package-inputs)
+                (propagated-inputs ,package-propagated-inputs))))
+
 (define (package-name-regexp package)
   "Return a regexp that matches PACKAGE's name as a word at the beginning of a
 line."
@@ -1493,6 +1524,10 @@ them for PACKAGE."
      (name        'inputs-should-not-be-input)
      (description "Identify inputs that shouldn't be inputs at all")
      (check       check-inputs-should-not-be-an-input-at-all))
+   (lint-checker
+     (name        'input-labels)
+     (description "Identify input labels that do not match package names")
+     (check       check-input-labels))
    (lint-checker
      (name        'license)
      ;; TRANSLATORS: <license> is the name of a data type and must not be
-- 
2.31.1