Check that we are parsing an actual Debian .buildinfo file, not just a file with that extension. (Closes: reproducible-builds/diffoscope#254, Debian:#987994)

This is caused by a bug in `file`:
    https://bugs.astron.com/view.php?id=256
Fixed by:
    https://github.com/file/file/commit/749e1ecfc3d333e5ec8b1a2e639da7ccb2498c34

Closes: reproducible-builds/diffoscope#251


Signed-off-by: Mattia Rizzolo <mattia@debian.org>

See: #251



Signed-off-by: Mattia Rizzolo <mattia@debian.org>

This is to make it easier to mangle the fixture at runtime.

Signed-off-by: Mattia Rizzolo <mattia@debian.org>

Closes: reproducible-builds/diffoscope#250


Signed-off-by: Mattia Rizzolo <mattia@debian.org>

Gbp-Dch: ignore

Gbp-Dch: ignore

If zipinfo(1) shows a difference but we cannot uncover a difference within the underlying .zip or .apk file, add a comment and show the binary comparison. (Closes: reproducible-builds/diffoscope#246)

Gbp-Dch: ignore

Signed-off-by: Holger Levsen <holger@layer-acht.org>

Gbp-Dch: ignore

tests: drop 'compose' from the list of required tools for these tests, since it doesn't seem to be required

Signed-off-by: Mattia Rizzolo <mattia@debian.org>

Signed-off-by: Mattia Rizzolo <mattia@debian.org>

Gbp-Dch: ignore

Test case: diffoscope /usr/share/doc/libsane-common/canon/canon.changes /usr/share/doc/libsane-common/canon/canon.changes

Gbp-Dch: ignore

Avoid frequent long lines in RPM header outputs that cause very slow HTML output. (Closes: reproducible-builds/diffoscope#245)

In F-Droid, we use diffoscope in automated verification of APKs.  We need to
include the diffoscope config and version in a JSON report so that the
scheduler can know whether it needs to rerun diffoscope on a file. If the
diffoscope configuration or version has changed, then it should be run again.

Gbp-Dch: ignore

This turns the output in reproducible-builds/diffoscope#245 from 32MB ->
26MB uncompressed (although almost neglible gain when gzipped, of course).

Gbp-Dch: ignore

Actually don't emit "Unable to stat file" debug messages at all; we have entirely-artificial directory "entries" such as ELF sections which, of course, will never exist as files.