[pve-devel] [PATCH proxmox-i18n] js generator: try to extract comments from source

[Maximiliano Sandoval <m.sandoval@proxmox.com>]

Adds a way to extract comments to the resulting .po files matching
xgettext's behaviour. Useful for instances like

```js
   // Translators: This is the verb, not the noun
   gettext("Profile");

   // Translators: This would read 'Manage OSD'
   Ext.String.format(gettext('Manage {0}'), 'OSD');
```

where the string is not enough to guarantee is a satisfactory
translation.

Do note that two identical messages with different comments will count
as the same message (same msgid) from the point of view of gettext. To
truly differentiate them one would need to support Context, see [1].

Caveats:
  - Cannot extract multiline comments
  - Does not understand comments in the /* comment */ form

[1] https://www.gnu.org/software/gettext/manual/html_node/Contexts.html

Signed-off-by: Maximiliano Sandoval <m.sandoval@proxmox.com>
---
 jsgettext.pl | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/jsgettext.pl b/jsgettext.pl
index 7f758fd..d0bf7a9 100755
--- a/jsgettext.pl
+++ b/jsgettext.pl
@@ -93,7 +93,7 @@ my $href = {
 };
 
 sub extract_msg {
-    my ($filename, $linenr, $line) = @_;
+    my ($filename, $linenr, $line, $comment) = @_;
 
     my $count = 0;
 
@@ -111,7 +111,7 @@ sub extract_msg {
 	if (my $po = $href->{$text}) {
 	    $po->reference($po->reference() . " $ref");
 	} else {
-	    $href->{$text} = Locale::PO->new(-msgid=> $text, -reference=> $ref, -msgstr=> '');
+	    $href->{$text} = Locale::PO->new(-msgid=> $text, -reference=> $ref, -msgstr=> '', -automatic=> $comment);
 	}
     }
     die "can't extract gettext message in '$filename' line $linenr\n" if !$count;
@@ -122,10 +122,13 @@ my $sources = find_js_sources($dirs);
 
 foreach my $s (@$sources) {
     open(my $SRC_FH, '<', $s) || die "unable to open file '$s' - $!\n";
+    my $prev_line;
     while(defined(my $line = <$SRC_FH>)) {
 	if ($line =~ m/gettext\s*\(/ && $line !~ m/^\s*function gettext/) {
-	    extract_msg($s, $., $line);
+	    my ($comment) = $prev_line =~ /\/\/\s+(.*)/;
+	    extract_msg($s, $., $line, $comment);
 	}
+	$prev_line = $line;
     }
     close($SRC_FH);
 }
-- 
2.39.2