doc: Clarify constraints for PO files.

Reported by Gábor Hojtsy <gabor.hojtsy@gmail.com> in
<https://savannah.gnu.org/bugs/?62677>.

* gettext-tools/doc/gettext.texi (PO Files): State uniqueness requirement.

diff --git a/gettext-tools/doc/gettext.texi b/gettext-tools/doc/gettext.texi
index 583573e4bd2c1d49ff249345d3be25b823fde846..b9aa7798fc1f3b0a29adc11e1742eb264436c5e0 100644 (file)
--- a/gettext-tools/doc/gettext.texi
+++ b/gettext-tools/doc/gettext.texi
@@ -1869,6 +1869,11 @@ this comment is most likely generated and managed by specialized GNU
 tools, and might disappear or be replaced unexpectedly when the PO
 file is given to @code{msgmerge}.
 
+For a PO file to be valid, no two entries without @code{msgctxt} may have
+the same @var{untranslated-string} or @var{untranslated-string-singular}.
+Similarly, no two entries may have the same @code{msgctxt} and the same
+@var{untranslated-string} or @var{untranslated-string-singular}.
+
 @node Sources
 @chapter Preparing Program Sources
 @cindex preparing programs for translation