Add TestTools with the nugetfuzz and decompdiff corpus tools - #4020
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siegfriedpammer wants to merge 2 commits into
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Add TestTools with the nugetfuzz and decompdiff corpus tools#4020siegfriedpammer wants to merge 2 commits into
siegfriedpammer wants to merge 2 commits into
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Both tools have found real decompiler defects (several merged fixes came out of nugetfuzz sweeps), but they only existed in a private checkout, so nobody else could run them and their setup knowledge lived in one head. They complement the fixture suite from the other side: it decompiles code we wrote, these decompile what the world ships. They stay outside the solution - file-based apps, run by hand, never by CI - and the near-empty Directory.Build.props/Directory.Packages.props keep the repo-wide warnings-as-errors, lock-file and central-package-management settings from reaching them. The catalog sweep driver is PowerShell rather than bash so it runs on Windows as well, which also drops its curl/jq dependency; staging falls back to copying when Windows withholds symlink privileges, and report file names are hash-truncated to stay inside the 260-character path limit. Assisted-by: Claude:claude-opus-5[1m]:Claude Code
A stalled request to nuget.org travelled out of the package run as an unhandled exception, so the report filed it as a decompiler [EXCEPTION] - the one bucket that has to hold nothing but real crashes - and the package was skipped without a single type being decompiled. Seen in the 2026-08-16 sweep, where common.logging.log4net timed out resolving its version list and decompiles clean on a second attempt. A 404 stays immediate: it is an answer, not a flake, and the sweep asks about plenty of ids that are not packages. Assisted-by: Claude:claude-opus-5[1m]:Claude Code
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Adds
TestTools/, two standalone tools that run the decompiler over real-worldassemblies. They complement the fixture suite from the other side: it decompiles
code we wrote, these decompile what the world ships.
nugetfuzz.csdecompdiff.csSeveral merged fixes came out of nugetfuzz sweeps (#3958, #3959, #3960, #3961),
but the tools only existed in a private checkout, so nobody else could run them
and their setup knowledge lived in one head.
Both are file-based apps:
single
.csfiles run withdotnet run <file>.cs. They are in no solution andnot run by CI. The near-empty
Directory.Build.props/Directory.Packages.propsstop MSBuild's upward search, so the repo-wide warnings-as-errors, lock-file and
central-package-management settings do not reach them (central package management
in particular rejects the inline
#:packageversion).nugetfuzz-all.ps1, the catalog sweep driver, is PowerShell rather than bash soit runs on Windows too, which also drops its curl/jq dependency. Two further
Windows adjustments:
decompdiffstaging falls back to copying when Windowswithholds symlink privileges, and report file names are hash-truncated to stay
inside the 260-character path limit.
TestTools/README.mddocuments usage, the reference-assembly handling and theplatform notes.
Verified on Linux: both tools build in-repo; a one-page/one-package sweep runs the
full download/decompile/ledger cycle;
decompdiff9.1 vs 11.0-preview overICSharpCode.Decompiler.dllreports 75 changed types with non-empty inline diffs.The Windows-specific paths are code-path fixes, not a tested run.