From 8d2e5d2192aeee25890376bbcae68cdef891ff5a Mon Sep 17 00:00:00 2001
From: Ian Jackson <ijackson@chiark.greenend.org.uk>
Date: Mon, 16 Jan 2017 01:11:51 +0000
Subject: gitattributes: Issue a warning on un-defused .gitattributes

Signed-off-by: Ian Jackson <ijackson@chiark.greenend.org.uk>
---
 dgit   | 34 ++++++++++++++++++++++++++++++++++
 dgit.7 | 10 ++++++++++
 2 files changed, 44 insertions(+)

diff --git a/dgit b/dgit
index be11a49..3d81558 100755
--- a/dgit
+++ b/dgit
@@ -144,6 +144,7 @@ our %opts_cfg_insertpos = map {
 
 sub parseopts_late_defaults();
 sub setup_gitattrs(;$);
+sub check_gitattrs($$);
 
 our $keyid;
 
@@ -3256,6 +3257,8 @@ END
 
     lrfetchref_used lrfetchref();
 
+    check_gitattrs($hash, "fetched source tree");
+
     unshift @end, $del_lrfetchrefs;
     return $hash;
 }
@@ -3370,6 +3373,35 @@ sub setup_new_tree () {
     setup_gitattrs();
 }
 
+sub check_gitattrs ($$) {
+    my ($treeish, $what) = @_;
+
+    return if is_gitattrs_setup;
+
+    local $/="\0";
+    my @cmd = (@git, qw(ls-tree -lrz --), "${treeish}:");
+    debugcmd "|",@cmd;
+    my $gafl = new IO::File;
+    open $gafl, "-|", @cmd or die $!;
+    while (<$gafl>) {
+	chomp or die;
+	s/^\d+\s+\w+\s+\w+\s+(\d+)\t// or die;
+	next if $1 == 0;
+	next unless m{(?:^|/)\.gitattributes$};
+
+	# oh dear, found one
+	print STDERR <<END;
+dgit: warning: $what contains .gitattributes
+dgit: .gitattributes have not been defused.  See GITATTRIBUTES in dgit(7).
+END
+	close $gafl;
+	return;
+    }
+    # tree contains no .gitattributes files
+    $?=0; $!=0; close $gafl or failedcmd @cmd;
+}
+
+
 sub multisuite_suite_child ($$$) {
     my ($tsuite, $merginputs, $fn) = @_;
     # in child, sets things up, calls $fn->(), and returns undef
@@ -6103,6 +6135,8 @@ sub import_dsc_result {
     my ($dstref, $newhash, $what_log, $what_msg) = @_;
     my @cmd = (@git, qw(update-ref -m), $what_log, $dstref, $newhash);
     runcmd @cmd;
+    check_gitattrs($newhash, "source tree");
+
     progress "dgit: import-dsc: $what_msg";
 }
 
diff --git a/dgit.7 b/dgit.7
index acc7cc1..09bb8f4 100644
--- a/dgit.7
+++ b/dgit.7
@@ -227,6 +227,16 @@ and dgit setup-new-tree
 disable transforming gitattributes
 by default,
 by creating a .git/info/attributes.
+When fetching or importing sources
+dgit warns if it finds .gitattributes file
+and the transforming gitattributes have not been defused
+(e.g. in the case of a tree not made with dgit clone).
+
+See
+.B dgit setup-new-tree
+and
+.B dgit setup-gitattributes
+in dgit(1).
 .SH PACKAGE SOURCE FORMATS
 If you are not the maintainer, you do not need to worry about the
 source format of the package.  You can just make changes as you like
-- 
cgit v1.2.3