test(visual): fail loud on cold-start across Pdf*Tests (#957 residu ii)

[jsboige]

What

Closes the remainder of the faux-vert class that #963 (f7875f68) opened for one harness. ai-01's body in #963 notes that EnsureTarget() in PdfDimensionTests / PdfSnapshotTests / PdfContentTests (~20 tests) carries the identical cold-start pattern and calls for the same correctif. This PR de-gates it.

The pattern: every test began if (!EnsureTarget()) return; where EnsureTarget() returned false on a missing Target/ with only an _output.WriteLine("Skipped…"). A missing Target/ → the test returned green without asserting anything. Pass-on-nothing.

The fix — a subtraction, not a counterweight

Identical to #963:

• private bool EnsureTarget() → private void EnsureTarget(); the silent return false body becomes Assert.Fail("…require a generated Target/ — run the pipeline first. This test verified nothing.").
• Every if (!EnsureTarget()) return; call site → EnsureTarget();.
• Secondary guards that also verified nothing get the same treatment — a partial Target/ (one language missing, a CardSet absent, the expected file not there) was passing silently too:
  • if (pdfs.Count == 0) return; → Assert.Fail
  • if (!Directory.Exists(dir)) return; → Assert.Fail
  • if (pdfs.Length == 0) return; → Assert.Fail
  • if (pdf == null) return; → Assert.Fail
  • if (sizes.Count < 2) return; → Assert.Fail
  • if (!File.Exists(pdfPath)) { WriteLine; return; } → Assert.Fail (PdfSnapshotTests)

No [Fact(Skip)] (static in xUnit 2.9.3 v2 — would kill the tests where they actually work). No continue-on-error. No fabricated coverage. Each Assert.Fail message names what was missing and ends "test verified nothing" so the intent is unmistakable in the runner output.

CI scope — verified (the DoD ask)

"Vérifie dans quel(s) leg(s) de CI ces tests tournent réellement avant de conclure sur l'impact."

• Argumentum.AssetConverter.VisualTests.csproj is in Argumentum Converters.sln → it is compiled by dotnet build (and by CI's build step).
• .github/workflows/build.yml Test step runs dotnet test "Generation/Converters/Argumentum.AssetConverter.Tests/Argumentum.AssetConverter.Tests.csproj" — targets only Tests.csproj, not VisualTests.

Impact: these Assert.Fails fire locally (developer / po-2023 running the pipeline then the visual suite), not in the release gate. CI stays green regardless. This matches #963's finding.

Files

File	Tests	Sites converted
PdfDimensionTests.cs	11	EnsureTarget method + 11 call sites + 7 secondary guards
PdfSnapshotTests.cs	3	EnsureTarget method + 3 call sites + 3 File.Exists guards
PdfContentTests.cs	6	EnsureTarget method + 6 call sites + 10 secondary guards

~20 tests total. Test code only.

Build / test

Build (compile proof):

dotnet build Argumentum.AssetConverter.VisualTests.csproj
→ La génération a réussi. 0 Avertissement(s) 0 Erreur(s)

Behaviour proof (one filtered test, --no-build): this machine's Target/ exists but has no generated PDFs (no Documents/density-0/) — the exact cold-start/partial state the fix targets.

dotnet test ...VisualTests.csproj --no-build --filter "FullyQualifiedName~A0_Pdf_Has_Correct_Dimensions"
→ Échoué! - échec: 4, réussite: 0, ignorée(s): 0, total: 4, durée: 13 ms
  Message: No A0 PDFs for fr in Target/ — test verified nothing (check pipeline output).
  at PdfDimensionTests.A0_Pdf_Has_Correct_Dimensions(...) line 77   ← the guard this PR added

These 4 failures ARE the fix working, not a regression. Before this PR, the same 4 variants passed green and silent (Target/ present → EnsureTarget() returned true → if (pdfs.Count == 0) return; skipped quietly). After, they fail loud at the exact line added here (line 77) with a message ending "test verified nothing". The EnsureTarget() Assert path itself is the identical pattern already shipped in #963 (f7875f68, merged & working); on this machine TargetRoot exists so that branch isn't reached — the secondary guards are, and they fire correctly.

A fully-green dotnet test over the whole VisualTests suite is assertable only by a machine that has run the generation pipeline (a populated Target/{lang}/Documents/density-0/ with PDFs) — a heavy lane run, out of scope for this test-code-only PR.

Scope

Test code only (~+30/−10, 3 files). 0 prod write, 0 CSV, 0 OWL, 0 CardPen. Base: ff80107b (ai-01 dispatch).

DoD (mirror #963)

• Mute return; removed, replaced by explicit Assert.Fail("…") — all 3 files
• A subtraction, not a counterweight — no [Fact(Skip)], no continue-on-error, no fabricated coverage
• CI legs verified — VisualTests compiled but NOT run by build.yml's Test step → fails locally, not in the release gate

🤖 po-2024