diffoscope: enable bloat by default

[gebner]

Motivation for this change

nix run nixpkgs.diffoscope -c diffoscope should start a full-featured diffoscope. Using a lot of external tools is literally one of the tagline features of diffoscope: "unpack archives of many kinds and transform various binary formats into more human-readable form".

This PR therefore changes the top-level attribute diffoscope to include the whole kitchen sink. A new diffoscopeMinimal attribute is added with the current feature set and smaller closure size.

Things done

• Tested using sandboxing (nix.useSandbox on NixOS, or option sandbox in nix.conf on non-NixOS linux)
• Built on platform(s)
  • NixOS
  • macOS
  • other Linux distributions
• Tested via one or more NixOS test(s) if existing and applicable for the change (look inside nixos/tests)
• Tested compilation of all pkgs that depend on this change using nix-shell -p nixpkgs-review --run "nixpkgs-review wip"
• Tested execution of all binary files (usually in ./result/bin/)
• Determined the impact on package closure size (by running nix path-info -S before and after)
• Ensured that relevant documentation is up to date
• Fits CONTRIBUTING.md.

[grahamc]

If I remember correctly "with bloat" cannot be built on Hydra because part of its build chain creates an output with a significantly large sparse file. However, the NAR format doesn't know about sparse files and the output becomes too large and is rejected.

[gebner]

Ah, that's unfortunate. Do you remember which package this was?

I'd really like hydra to build the full version because the python tests take quite some time to run.

[r-rmcgibbo]

Result of nixpkgs-review pr 121042 at b6d7559 run on x86_64-linux 1

2 packages built successfully:

• diffoscope
• diffoscopeMinimal

[gebner]

Another alternative would be to reduce the number of tools disabled by enableBloat = false. Upstream has a much less restrictive list of "huge" tools:

# Set of tools considered "large" their installation size, or too niche in
# their target users.  To be easily excluded from installation if not
# specifically required.
# These are the names of the tools, not package names.
HUGE_TOOLS = {
    "ghc",
    "ocamlobjinfo",
    "llvm-bcanalyzer",
    "llvm-config",
    "llvm-dis",
    "ppudump",
    "javap",
    "ssconvert",
    "apktool",
    "apksigner",
    "pedump",
    "radare2",
    "dumpxsb",
}

[grahamc]

Since every dependency of diffoscope with bloat enabled was pre-built by hydra, I'm forced to conclude I am misremembering :)

👍