test: Add Dpkg::File unit tests

scripts/Makefile.am

@@ -279,6 +279,7 @@ test_data = \
 	t/Dpkg_Dist_Files/files-byhand \
 	t/Dpkg_Dist_Files/files-fragment-a \
 	t/Dpkg_Dist_Files/files-fragment-b \
+	t/Dpkg_File/slurp-me \
 	t/Dpkg_OpenPGP/package_1.0.orig.tar \
 	t/Dpkg_OpenPGP/package_1.0.orig.tar.asc \
 	t/Dpkg_OpenPGP/package_1.0.orig.tar.sig \

scripts/t/Dpkg_File.t

@@ -16,12 +16,40 @@
 use strict;
 use warnings;
 
-use Test::More tests => 1;
+use Test::More tests => 4;
+use Test::Dpkg qw(:paths);
 
 BEGIN {
     use_ok('Dpkg::File');
 }
 
-# TODO: Add actual test cases.
+my $datadir = test_get_data_path();
+
+my ($data, $data_ref, $data_fh);
+
+$data = file_slurp("$datadir/slurp-me");
+$data_ref = <<'DATA';
+first line
+next line
+final line
+DATA
+is($data, $data_ref, 'slurped data');
+
+open $data_fh, '<', "$datadir/slurp-me"
+    or die "cannot open $datadir/slurp-me for reading: $!";
+my $discard = <$data_fh>;
+$data = file_slurp($data_fh);
+close $data_fh;
+$data_ref = <<'DATA';
+next line
+final line
+DATA
+is($data, $data_ref, 'slurped partial data');
+
+$data = undef;
+eval {
+    $data = file_slurp("$datadir/non-existent");
+};
+ok($@, 'cannot slurp missing file');
 
 1;

scripts/t/Dpkg_File/slurp-me

+first line
+next line
+final line