find: omit warning diagnostic for -name '/'

Although usually a pattern containing a directory separator does not match
anything, a pattern solely consisting of one '/' still does (and has to)
for the root directory "/".

* find/parser.c (check_name_arg): Omit the warning in the case the
given pattern equals "/".
find/find.1 (-name): Clarify better that the pattern "/" is valid to
match the "/" directory.
* init.cfg (find_emits_warnings_): Add utility function.
* tests/find/name-slash.sh: Add test.
* tests/local.mk (all_tests): Reference it.
* MEWS (Bug Fixes): Mention the fix.

Fixes https://savannah.gnu.org/bugs/?62227

1 files changed, 9 insertions, 0 deletions

diff --git a/init.cfg b/init.cfg
index 5e422291..98423613 100644
--- a/init.cfg
+++ b/init.cfg
@@ -514,6 +514,15 @@ fiemap_capable_()
   python "$abs_srcdir"/tests/fiemap-capable "$@"
 }
 
+# Determine if find(1) emits warnings.  This is not the case
+# e.g. if stdin is not a tty.
+find_emits_warnings_()
+{
+  # Find usually emits a warning for the deprecated -d option.
+  find -maxdepth 0 -d -quit 2>&1 \
+    | grep -q 'warning:'
+}
+
 # Skip the current test if "." lacks d_type support.
 require_dirent_d_type_()
 {