[PATCH 11/13] v2writable: clarify header cleanups

["Eric Wong (Contractor, The Linux Foundation)" <e@80x24.org>]

We want to make it clear to the code and DEBUG_DIFF users
that we do not introduce messages with unsuitable headers
into public archives.
---
 lib/PublicInbox/Import.pm     | 12 +++++++++---
 lib/PublicInbox/V2Writable.pm |  7 +++++++
 2 files changed, 16 insertions(+), 3 deletions(-)

diff --git a/lib/PublicInbox/Import.pm b/lib/PublicInbox/Import.pm
index d69934b..5d116a1 100644
--- a/lib/PublicInbox/Import.pm
+++ b/lib/PublicInbox/Import.pm
@@ -288,6 +288,14 @@ sub extract_author_info ($) {
 	($name, $email);
 }
 
+# kill potentially confusing/misleading headers
+sub drop_unwanted_headers ($) {
+	my ($mime) = @_;
+
+	$mime->header_set($_) for qw(bytes lines content-length status);
+	$mime->header_set($_) for @PublicInbox::MDA::BAD_HEADERS;
+}
+
 # returns undef on duplicate
 # returns the :MARK of the most recent commit
 sub add {
@@ -321,9 +329,7 @@ sub add {
 		_check_path($r, $w, $tip, $path) and return;
 	}
 
-	# kill potentially confusing/misleading headers
-	$mime->header_set($_) for qw(bytes lines content-length status);
-	$mime->header_set($_) for @PublicInbox::MDA::BAD_HEADERS;
+	drop_unwanted_headers($mime);
 
 	# spam check:
 	if ($check_cb) {
diff --git a/lib/PublicInbox/V2Writable.pm b/lib/PublicInbox/V2Writable.pm
index 605f688..44b5528 100644
--- a/lib/PublicInbox/V2Writable.pm
+++ b/lib/PublicInbox/V2Writable.pm
@@ -223,6 +223,12 @@ sub remove {
 	my $mm = $skel->{mm};
 	my $removed;
 	my $mids = mids($mime->header_obj);
+
+	# We avoid introducing new blobs into git since the raw content
+	# can be slightly different, so we do not need the user-supplied
+	# message now that we have the mids and content_id
+	$mime = undef;
+
 	foreach my $mid (@$mids) {
 		$srch->reopen->each_smsg_by_mid($mid, sub {
 			my ($smsg) = @_;
@@ -430,6 +436,7 @@ sub diff ($$$) {
 	print $ah $cur->as_string or die "print: $!";
 	close $ah or die "close: $!";
 	my ($bh, $bn) = tempfile('email-new-XXXXXXXX');
+	PublicInbox::Import::drop_unwanted_headers($new);
 	print $bh $new->as_string or die "print: $!";
 	close $bh or die "close: $!";
 	my $cmd = [ qw(diff -u), $an, $bn ];
-- 
EW