6 ms·

Diffoscope: in-depth comparison of files, archives, and directories

70 points by chei0aiV 11y ago

girfan 11y ago
Is this built on top of the standard Unix "diff" program?
jmickey 11y ago
How does this differ from Meld or WinDiff?
etwigg 11y ago
Looks great! Shameless plug: DiffPlug can also diff arbitrarily nested zip/tar/gz, runs on Win/Mac/Linux, and supports text/image/other stuff too. It's closed-source and GUI, but you can control it from the command line, and we're working on an Apache 2.0 API for building the differ plugins. Open API for differs (totally incomplete, but we've already released some its pre-reqs): https://github.com/diffplug/opendiff https://github.com/diffplug/opendiff Archives and filesystems that we support: https://docs.diffplug.com/1.6.1/Filesystems/ https://docs.diffplug.com/1.6.1/Filesystems/
amelius 11y ago
Why not build a tool for every file format that simply dumps the contents of the file in a human-readable way. Then feed the output through "diff". That approach would sound more "unix-ey" to me.
- etwigg 11y ago
  Great idea! That would work well for a lot of stuff, but I don't think it would scale to diffing, say, two 4Gb iso files. Also, some structured content has user-hidden IDs which can help a differ, but they probably wouldn't show up in a "human-readable" representation.
  - amelius 11y ago
    The human-readable representation can be as long as you want. Also, one could embed checksums in the output, so that if non-displayed contents differs that would trigger an output by the diff command (granted, this way it is not so human-readable anymore because of the checksum, but it would still be a more modular approach).
    - etwigg 11y ago
      I don't think diff will perform well on two 4gb inputs. I agree there should be a modular approach, but I don't think flat text is the best lowest-common-denominator. Your proposal would certainly work for a lot of cases though, and it is very unix-y!
fit2rule 11y ago
Repo seems to be down or invalid - anyone know where I can find the sources? I'd love to attempt to port this to OSX ..
davvid 11y ago
It looks like this may be a premature announcement because the installation instructions don't work, specifically the debian notes. If someone is listening, I would suggest adding a SYNOPSIS section to the documentation with the command-line usage. e.g., does it support 3-way base/local/remote diffs? `git difftool` knows about a lot of these kinda tools.. if this one looks promising (it's free, so that's already a plus) then we can teach difftool about it. I guess I'll wait and see if it materializes. Adding support to git is pretty simple: create `mergetools/diffoscope` with this (I'm guessing the cli syntax, but you get the idea): diff_cmd () { "$merge_tool_path" "$LOCAL" "$REMOTE" } merge_cmd () { if $base_present then "$merge_tool_path" --output "$MERGED" "$BASE" "$LOCAL" "$REMOTE" else "$merge_tool_path" --output "$MERGED" "$LOCAL" "$REMOTE" fi } In an existing git installation, that scriptlet can be copied to `$(git --exec-path)/mergetools/diffoscope`. It can then be used as `git difftool -t diffoscope`.
jakeogh 11y ago
Cool! Reminds me of kdiff3 but can do terminal output. Nice.
jakeogh 11y ago
$ git clone https://anonscm.debian.org/git/reproducible/diffoscope.git https://anonscm.debian.org/git/reproducible/diffoscope.git Cloning into 'diffoscope'... fatal: repository 'https://anonscm.debian.org/git/reproducible/diffoscope.git/' https://anonscm.debian.org/git/reproducible/diffoscope.git/' not found
- chei0aiV 11y ago
  The link was indeed posted a bit early. It is currently still named "debbindiff", but will be renamed soon. At the moment it can still be found here: https://alioth.debian.org/plugins/scmgit/cgi-bin/gitweb.cgi?p=reproducible/debbindiff.git;a=summary https://alioth.debian.org/plugins/scmgit/cgi-bin/gitweb.cgi?...
chei0aiV 11y ago
diffoscope is now available in Debian sid.

70 points by chei0aiV 11y ago

girfan 11y ago

Is this built on top of the standard Unix "diff" program?

jmickey 11y ago

How does this differ from Meld or WinDiff?

etwigg 11y ago

Looks great! Shameless plug: DiffPlug can also diff arbitrarily nested zip/tar/gz, runs on Win/Mac/Linux, and supports text/image/other stuff too. It's closed-source and GUI, but you can control it from the command line, and we're working on an Apache 2.0 API for building the differ plugins. Open API for differs (totally incomplete, but we've already released some its pre-reqs): https://github.com/diffplug/opendiff https://github.com/diffplug/opendiff Archives and filesystems that we support: https://docs.diffplug.com/1.6.1/Filesystems/ https://docs.diffplug.com/1.6.1/Filesystems/

amelius 11y ago

Why not build a tool for every file format that simply dumps the contents of the file in a human-readable way. Then feed the output through "diff". That approach would sound more "unix-ey" to me.

etwigg 11y ago
Great idea! That would work well for a lot of stuff, but I don't think it would scale to diffing, say, two 4Gb iso files. Also, some structured content has user-hidden IDs which can help a differ, but they probably wouldn't show up in a "human-readable" representation.
- amelius 11y ago
  The human-readable representation can be as long as you want. Also, one could embed checksums in the output, so that if non-displayed contents differs that would trigger an output by the diff command (granted, this way it is not so human-readable anymore because of the checksum, but it would still be a more modular approach).
  - etwigg 11y ago
    I don't think diff will perform well on two 4gb inputs. I agree there should be a modular approach, but I don't think flat text is the best lowest-common-denominator. Your proposal would certainly work for a lot of cases though, and it is very unix-y!

fit2rule 11y ago

Repo seems to be down or invalid - anyone know where I can find the sources? I'd love to attempt to port this to OSX ..

davvid 11y ago

It looks like this may be a premature announcement because the installation instructions don't work, specifically the debian notes. If someone is listening, I would suggest adding a SYNOPSIS section to the documentation with the command-line usage. e.g., does it support 3-way base/local/remote diffs? `git difftool` knows about a lot of these kinda tools.. if this one looks promising (it's free, so that's already a plus) then we can teach difftool about it. I guess I'll wait and see if it materializes. Adding support to git is pretty simple: create `mergetools/diffoscope` with this (I'm guessing the cli syntax, but you get the idea): diff_cmd () { "$merge_tool_path" "$LOCAL" "$REMOTE" } merge_cmd () { if $base_present then "$merge_tool_path" --output "$MERGED" "$BASE" "$LOCAL" "$REMOTE" else "$merge_tool_path" --output "$MERGED" "$LOCAL" "$REMOTE" fi } In an existing git installation, that scriptlet can be copied to `$(git --exec-path)/mergetools/diffoscope`. It can then be used as `git difftool -t diffoscope`.

jakeogh 11y ago

Cool! Reminds me of kdiff3 but can do terminal output. Nice.

jakeogh 11y ago

$ git clone https://anonscm.debian.org/git/reproducible/diffoscope.git https://anonscm.debian.org/git/reproducible/diffoscope.git Cloning into 'diffoscope'... fatal: repository 'https://anonscm.debian.org/git/reproducible/diffoscope.git/' https://anonscm.debian.org/git/reproducible/diffoscope.git/' not found

chei0aiV 11y ago
The link was indeed posted a bit early. It is currently still named "debbindiff", but will be renamed soon. At the moment it can still be found here: https://alioth.debian.org/plugins/scmgit/cgi-bin/gitweb.cgi?p=reproducible/debbindiff.git;a=summary https://alioth.debian.org/plugins/scmgit/cgi-bin/gitweb.cgi?...

chei0aiV 11y ago

diffoscope is now available in Debian sid.