Vendor packse scenarios and cross-check against a SAT oracle

.github/workflows/ci.yml

@@ -99,6 +99,28 @@ jobs:
             echo "::error::The equivalence check did not report a fast-mode comparison, so it did not run."
             exit 1
           fi
+      # packse scenarios cross-checked against a SAT oracle, run the same way and
+      # for the same reason as the two steps above: a mistyped -run exits 0 while
+      # asserting nothing, and a silent SKIP would hide a scenario going untested
+      # instead of failing loudly. See resolver/testdata/packse/README.md.
+      - name: packse and SAT oracle (must not skip)
+        shell: bash
+        run: |
+          set -euo pipefail
+          go test ./resolver/ -run 'TestPackse|TestSATOracle' -v -count=1 -timeout 20m \
+            | tee packse.log
+          if grep -q -e '--- SKIP' packse.log; then
+            echo "::error::A packse or SAT oracle test skipped. These must run on every PR."
+            exit 1
+          fi
+          if ! grep -qE 'packse: [0-9]+ scenarios = ' packse.log; then
+            echo "::error::TestPackse did not print its summary line, so it did not run."
+            exit 1
+          fi
+          if ! grep -qE 'SAT oracle: cross-checked [0-9]+ scenarios' packse.log; then
+            echo "::error::TestSATOracle did not print its summary line, so it did not run."
+            exit 1
+          fi
       - name: Format check
         run: |
           unformatted=$(gofmt -l .)

NOTICE

@@ -48,3 +48,17 @@ github.com/posit-dev/go-python-packaging, used for PEP 440 versions and PEP 508
 requirements, is Copyright (c) Posit Software, PBC, licensed under the Apache
 License, Version 2.0, or the MIT license. See that project's own NOTICE for the
 upstreams it in turn credits.
+
+resolver/testdata/packse contains scenario files copied from astral-sh/packse
+(https://github.com/astral-sh/packse), Copyright (c) 2023 Astral Software Inc.,
+dual-licensed under the Apache License, Version 2.0, or the MIT license. See
+resolver/testdata/packse/README.md for the pinned commit and how they were
+copied.
+
+github.com/crillab/gophersat, used as a SAT-solver cross-check in the resolver
+package's tests, is Copyright (c) 2017 Centre de Recherche en Informatique de
+Lens and contributors, licensed under the MIT license. Test-only dependency.
+
+github.com/BurntSushi/toml, used to parse the packse scenario fixtures in the
+resolver package's tests, is licensed under the MIT license. Test-only
+dependency.

go.mod

@@ -3,6 +3,8 @@ module github.com/posit-dev/go-pyresolver
 go 1.25.0
 
 require (
+	github.com/BurntSushi/toml v1.6.0
+	github.com/crillab/gophersat v1.4.0
 	github.com/klauspost/compress v1.19.2
 	github.com/posit-dev/go-pubgrub v0.2.1
 	github.com/posit-dev/go-python-packaging v0.7.0

go.sum

@@ -1,3 +1,7 @@
+github.com/BurntSushi/toml v1.6.0 h1:dRaEfpa2VI55EwlIW72hMRHdWouJeRF7TPYhI+AUQjk=
+github.com/BurntSushi/toml v1.6.0/go.mod h1:ukJfTF/6rtPPRCnwkur4qwRxa8vTRFBF0uk2lLoLwho=
+github.com/crillab/gophersat v1.4.0 h1:irf9ajKmNnEURjgPU4oz+ouqIXXLQ59ZNd3NC+hULMc=
+github.com/crillab/gophersat v1.4.0/go.mod h1:gDzeMEBrqJR20IL9JW25tFHNGLU5+GDeJzr0zpi3mxs=
 github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/klauspost/compress v1.19.2 h1:hMRETovs/pu/dVWN7zIT1PGG8t509MwT6bO7XSi26R8=