lint: Improve check for synopses starting with package name.

* guix/scripts/lint.scm (package-name-regexp): New procedure.
  (check-synopsis-style)[check-start-with-package-name]: Use it instead
  of 'string-prefix-ci?'.
* tests/lint.scm ("synopsis: start with package name prefix"): New test.

1 files changed, 8 insertions, 0 deletions

diff --git a/tests/lint.scm b/tests/lint.scm
index 2f62adc39f3..9a043c4b59a 100644
--- a/tests/lint.scm
+++ b/tests/lint.scm
@@ -194,6 +194,14 @@
                           (check-synopsis-style pkg))))
                     "synopsis should not start with the package name")))
 
+(test-assert "synopsis: start with package name prefix"
+  (string-null?
+   (call-with-warnings
+    (lambda ()
+      (let ((pkg (dummy-package "arb"
+                   (synopsis "Arbitrary precision"))))
+        (check-synopsis-style pkg))))))
+
 (test-assert "inputs: pkg-config is probably a native input"
   (->bool
    (string-contains