feat(preflight): evaluate optional-content membership for print and screen (#115)

UnitTests/tst_preflightenginetest.cpp

@@ -42,6 +42,7 @@
 #include <QJsonObject>
 #include <QPainter>
 #include <QTemporaryDir>
+#include <QTemporaryFile>
 
 #include <algorithm>
 #include <vector>
@@ -83,6 +84,8 @@ private slots:
     void fontIntegrity_checkIsRegistered();
     void run_fontIntegrity_keepsValidEmbeddedFixtureClean();
     void hiddenContent_checksAreRegistered();
+    void run_hiddenLayers_reportsOcmdScreenPrintDivergence();
+    void run_hiddenLayers_reportsUnevaluableMembershipAsIncomplete();
     void run_offPageContent_detectsMarksOutsideToleratedBox();
     void run_includesProfileFixups();
     void run_synthesizesAddBleedWhenGapAndNoProfileFixup();
@@ -910,6 +913,103 @@ void PreflightEngineTest::hiddenContent_checksAreRegistered()
     QVERIFY(engine.hasCheck(QStringLiteral("obscured-content")));
 }
 
+void PreflightEngineTest::run_hiddenLayers_reportsOcmdScreenPrintDivergence()
+{
+    const QString fixturePath = QStringLiteral(LOOP_PREFLIGHT_SOURCE_DIR "/testdata/fixtures/ocmd-print-divergence.pdf");
+    QVERIFY(QFile::exists(fixturePath));
+
+    pdf::PDFDocumentReader reader(nullptr, [](bool*)
+                                  { return QString(); }, true, false);
+    pdf::PDFDocument document = reader.readFromFile(fixturePath);
+    QCOMPARE(reader.getReadingResult(), pdf::PDFDocumentReader::Result::OK);
+
+    pdf::PDFDocumentSession session(&document);
+    pdf::PreflightEngine engine(&session);
+    const QJsonObject profile{
+        { QStringLiteral("name"), QStringLiteral("Hidden layers") },
+        { QStringLiteral("checks"), QJsonArray{
+                                        QJsonObject{ { QStringLiteral("id"), QStringLiteral("hidden-layers") },
+                                                     { QStringLiteral("severity"), QStringLiteral("warning") } } } }
+    };
+
+    const pdf::PreflightResult result = engine.run(profile);
+    QVERIFY(result.errors.isEmpty());
+    QCOMPARE(result.warnings.size(), 5);
+
+    QMap<QString, QString> directions;   // policy -> "view/print"
+    for (const pdf::PreflightFinding& finding : result.warnings)
+    {
+        QCOMPARE(finding.checkId, QStringLiteral("hidden-layers"));
+        QCOMPARE(finding.page, 1);
+        QCOMPARE(finding.evidence.value(QStringLiteral("governor")).toString(), QStringLiteral("ocmd"));
+        QCOMPARE(finding.evidence.value(QStringLiteral("divergence")).toBool(), true);
+        QVERIFY(!finding.evidence.value(QStringLiteral("ocg_names")).toArray().isEmpty());
+        directions.insert(finding.evidence.value(QStringLiteral("policy")).toString(),
+                          finding.evidence.value(QStringLiteral("view_state")).toString() + QLatin1Char('/') + finding.evidence.value(QStringLiteral("print_state")).toString());
+    }
+
+    QCOMPARE(directions.value(QStringLiteral("AllOn")), QStringLiteral("on/off"));
+    QCOMPARE(directions.value(QStringLiteral("AnyOn")), QStringLiteral("off/on"));
+    QCOMPARE(directions.value(QStringLiteral("AllOff")), QStringLiteral("off/on"));
+    QCOMPARE(directions.value(QStringLiteral("AnyOff")), QStringLiteral("off/on"));
+    QCOMPARE(directions.value(QStringLiteral("VE")), QStringLiteral("off/on"));
+}
+
+void PreflightEngineTest::run_hiddenLayers_reportsUnevaluableMembershipAsIncomplete()
+{
+    // The visibility expression names an operator the specification does not define.
+    const QByteArray content("/OC /M BDC 0 0 0 rg 10 10 20 20 re f EMC\n");
+    const QList<QByteArray> objects{
+        "<< /Type /Catalog /Pages 2 0 R /OCProperties << /OCGs [ 5 0 R ] /D << /BaseState /ON >> >> >>",
+        "<< /Type /Pages /Kids [ 3 0 R ] /Count 1 >>",
+        "<< /Type /Page /Parent 2 0 R /MediaBox [ 0 0 100 100 ] /Contents 4 0 R "
+        "/Resources << /Properties << /M 6 0 R >> >> >>",
+        "<< /Length " + QByteArray::number(content.size()) + " >>\nstream\n" + content + "endstream",
+        "<< /Type /OCG /Name (Layer) >>",
+        "<< /Type /OCMD /VE [ /Xor 5 0 R 5 0 R ] >>"
+    };
+
+    QByteArray bytes("%PDF-1.7\n");
+    QList<int> offsets;
+    for (int index = 0; index < objects.size(); ++index)
+    {
+        offsets.append(bytes.size());
+        bytes += QByteArray::number(index + 1) + " 0 obj\n" + objects.at(index) + "\nendobj\n";
+    }
+    const int xref = bytes.size();
+    bytes += "xref\n0 " + QByteArray::number(objects.size() + 1) + "\n0000000000 65535 f \n";
+    for (int offset : offsets)
+    {
+        bytes += QByteArray::number(offset).rightJustified(10, '0') + " 00000 n \n";
+    }
+    bytes += "trailer\n<< /Size " + QByteArray::number(objects.size() + 1) + " /Root 1 0 R >>\nstartxref\n" +
+             QByteArray::number(xref) + "\n%%EOF\n";
+
+    QTemporaryFile file;
+    QVERIFY(file.open());
+    file.write(bytes);
+    file.flush();
+
+    pdf::PDFDocumentReader reader(nullptr, [](bool*)
+                                  { return QString(); }, true, false);
+    pdf::PDFDocument document = reader.readFromFile(file.fileName());
+    QCOMPARE(reader.getReadingResult(), pdf::PDFDocumentReader::Result::OK);
+
+    pdf::PDFDocumentSession session(&document);
+    pdf::PreflightEngine engine(&session);
+    const QJsonObject profile{
+        { QStringLiteral("name"), QStringLiteral("Hidden layers") },
+        { QStringLiteral("checks"), QJsonArray{
+                                        QJsonObject{ { QStringLiteral("id"), QStringLiteral("hidden-layers") },
+                                                     { QStringLiteral("severity"), QStringLiteral("warning") } } } }
+    };
+
+    const pdf::PreflightResult result = engine.run(profile);
+    QVERIFY(!result.pass);
+    QCOMPARE(result.errors.size(), 1);
+    QCOMPARE(result.errors.first().evidence.value(QStringLiteral("inspection_complete")).toBool(), false);
+}
+
 void PreflightEngineTest::run_offPageContent_detectsMarksOutsideToleratedBox()
 {
     pdf::PDFDocumentBuilder builder;

changes/cc-issue-115-ocmd-membership.evidence.yaml

@@ -0,0 +1,29 @@
+format_version: 1
+kind: evidence
+claims:
+  - id: ocmd-print-divergence-regression-fixture
+    evidence:
+      - integration:UnitTestsPreflightCorpus
+      - architecture:loop-preflight/testdata/fixtures
+      - architecture:docs/generated/preflight-check-catalog.json
+      - architecture:docs/generated/architecture-catalog.json
+      - architecture:docs/generated/preflight-corpus-coverage.json
+  - id: ocmd-membership-print-evaluation
+    evidence:
+      - unit:agent-policy:core
+      - unit:agent-policy:preflight
+      - unit:UnitTestsPreflightChecks
+      - unit:UnitTestsPreflightEngine
+      - unit:UnitTestsPreflightInteraction
+      - unit:UnitTestsPreflightVerdict
+      - unit:UnitTestsPreflightProfileResolver
+      - unit:UnitTestsProfileIdentity
+      - unit:UnitTestsOperatorAcceptance
+      - integration:UnitTestsPreflightWorkflowAcceptance
+      - differential:UnitTestsStandardOracle
+      - differential:UnitTestsConversionOracle
+      - security:scripts/ci/check_source_integrity.py
+unresolved:
+  - core:scripts/ci/check_independent_validation_gate.py
+  - Only UnitTestsPreflightEngine and UnitTestsPreflightCorpus were built and run locally; the other listed unit, integration and differential lanes are proven by the linux-build and windows-build CI lanes, not by this worktree.
+  - Alternate optional-content configurations are not evaluated, and an /OC entry on a Form XObject or annotation that is never painted is not inspected.

changes/cc-issue-115-ocmd-membership.md

@@ -0,0 +1,6 @@
+# Evaluate optional-content membership for hidden content (#115)
+
+Category: fixed
+Audience: prepress operators and preflight maintainers relying on hidden-layers
+Breaking-Change: no
+Summary: hidden-layers now evaluates optional-content membership dictionaries (every /P policy and /VE expression) on marked content, Form XObject /OC entries and annotation /OC entries under both the View and Print usages with the default configuration's /AS events, and reports content that is hidden in print or differs between screen and print; a governor it cannot evaluate is reported incomplete instead of clean. Adds the ocmd-print-divergence regression fixture and lands the hidden-layers-ocmd backlog row.

docs/generated/preflight-check-catalog.json

@@ -405,14 +405,22 @@
         "message",
         "check_id",
         "evidence.confidence",
-        "evidence.ocg_name"
+        "evidence.ocg_name",
+        "evidence.governor",
+        "evidence.governor_source",
+        "evidence.policy",
+        "evidence.ocg_names",
+        "evidence.view_state",
+        "evidence.print_state",
+        "evidence.divergence",
+        "evidence.inspection_complete"
       ],
       "families": [
         "packaging"
       ],
       "fixups": [],
-      "limitations": "Does not enumerate every OCMD combination.",
-      "measures": "Optional content groups that hide print content.",
+      "limitations": "Evaluates the default configuration under the View and Print usages with its /AS events; alternate configurations and content an /OC entry governs on Form XObjects or annotations that are never painted are not evaluated. A governor that cannot be evaluated is reported incomplete.",
+      "measures": "Optional content groups and membership dictionaries (/P AnyOn, AllOn, AnyOff, AllOff and /VE) that hide print content, and content whose visibility differs between screen and print.",
       "parameters": [
         {
           "default": 9.0,
@@ -424,7 +432,7 @@
       ],
       "severity": [
         {
-          "condition": "an optional-content group referenced by print content is not printable by default. The profile's check severity (error|warning|info, default error) replaces it and warning/info route the finding to warnings.",
+          "condition": "an optional-content group referenced by print content is not printable by default, or a membership dictionary governing marked content, a Form XObject or an annotation is hidden in print or differs between screen and print; an optional-content governor that cannot be evaluated is forced to error with inspection_complete false. The profile's check severity (error|warning|info, default error) replaces the others and warning/info route the finding to warnings.",
           "finding_type": "hidden-layers",
           "severity": "error"
         }

docs/generated/preflight-corpus-coverage.json

@@ -129,7 +129,8 @@
       "corpus_gap": null,
       "coverage": "partial",
       "finding_fixtures": [
-        "hidden-layers"
+        "hidden-layers",
+        "ocmd-print-divergence"
       ],
       "uninspected_fixtures": []
     },
@@ -272,6 +273,6 @@
     }
   },
   "snapshot_dir": "loop-preflight/testdata/snapshots",
-  "source_fixtures": 76,
+  "source_fixtures": 77,
   "unattributed_findings": 1
 }

docs/generated/preflight-coverage-backlog.json

@@ -311,15 +311,15 @@
       "state": "landed"
     },
     {
-      "closed_by": "#115",
+      "closed_by": "hidden-layers",
       "deferral": null,
       "families": [
         "packaging"
       ],
-      "gap": "the shared hidden-content scan does not enumerate every optional-content membership-dictionary combination, so an unprintable configuration passes clean",
+      "gap": "membership dictionaries (every /P policy and /VE expressions) on marked content, Form XObjects and annotations were not evaluated for print, so an unprintable configuration passed clean; hidden-layers now evaluates them under the View and Print usages and reports screen-versus-print divergence (filed as #115)",
       "id": "hidden-layers-ocmd",
       "priority": "P2",
-      "state": "open"
+      "state": "landed"
     },
     {
       "closed_by": "#116",

docs/preflight-check-catalog-overlay.json

@@ -549,8 +549,8 @@
    "fixups": []
   },
   "hidden-layers": {
-   "measures": "Optional content groups that hide print content.",
-   "limitations": "Does not enumerate every OCMD combination.",
+   "measures": "Optional content groups and membership dictionaries (/P AnyOn, AllOn, AnyOff, AllOff and /VE) that hide print content, and content whose visibility differs between screen and print.",
+   "limitations": "Evaluates the default configuration under the View and Print usages with its /AS events; alternate configurations and content an /OC entry governs on Form XObjects or annotations that are never painted are not evaluated. A governor that cannot be evaluated is reported incomplete.",
    "coverage": "partial",
    "families": [
     "packaging"
@@ -568,7 +568,7 @@
     {
      "finding_type": "hidden-layers",
      "severity": "error",
-     "condition": "an optional-content group referenced by print content is not printable by default. The profile's check severity (error|warning|info, default error) replaces it and warning/info route the finding to warnings."
+     "condition": "an optional-content group referenced by print content is not printable by default, or a membership dictionary governing marked content, a Form XObject or an annotation is hidden in print or differs between screen and print; an optional-content governor that cannot be evaluated is forced to error with inspection_complete false. The profile's check severity (error|warning|info, default error) replaces the others and warning/info route the finding to warnings."
     }
    ],
    "evidence": [
@@ -578,7 +578,15 @@
     "message",
     "check_id",
     "evidence.confidence",
-    "evidence.ocg_name"
+    "evidence.ocg_name",
+    "evidence.governor",
+    "evidence.governor_source",
+    "evidence.policy",
+    "evidence.ocg_names",
+    "evidence.view_state",
+    "evidence.print_state",
+    "evidence.divergence",
+    "evidence.inspection_complete"
    ],
    "fixups": []
   },
@@ -1494,12 +1502,12 @@
   {
    "id": "hidden-layers-ocmd",
    "priority": "P2",
-   "gap": "the shared hidden-content scan does not enumerate every optional-content membership-dictionary combination, so an unprintable configuration passes clean",
+   "gap": "membership dictionaries (every /P policy and /VE expressions) on marked content, Form XObjects and annotations were not evaluated for print, so an unprintable configuration passed clean; hidden-layers now evaluates them under the View and Print usages and reports screen-versus-print divergence (filed as #115)",
    "families": [
     "packaging"
    ],
-   "state": "open",
-   "closed_by": "#115",
+   "state": "landed",
+   "closed_by": "hidden-layers",
    "deferral": null
   },
   {

loop-preflight/README.md

@@ -94,6 +94,15 @@ is observed; it does not claim full compositing equivalence. Off-page content
 is tolerated inside the page BleedBox, or inside the configured allowance when
 no BleedBox exists. These checks do not register corrective fixups.
 
+`hidden-layers` evaluates every optional-content governor it meets under both
+the View and the Print usage, with the default configuration's `/AS` events
+applied: groups and membership dictionaries (`/P` AnyOn, AllOn, AnyOff, AllOff
+and `/VE` expressions) on marked content, on Form XObject `/OC` entries and on
+annotation `/OC` entries. It reports membership hidden in print and content
+that differs between screen and print, in either direction, with
+`evidence.view_state`, `evidence.print_state` and `evidence.policy`. A governor
+that cannot be evaluated is reported with `inspection_complete: false`.
+
 The `transparency-risk` check has no additional parameters; it observes
 transparency groups, blend modes, and blend-space crossings.
 

loop-preflight/testdata/fixtures/manifest.json

@@ -861,6 +861,17 @@
     "source": "hand-built",
     "notes": "#668 corpus gap: optional-content group OFF by default with OC-marked content."
   },
+  {
+    "id": "ocmd-print-divergence",
+    "pdf": "ocmd-print-divergence.pdf",
+    "profile": "testdata/profiles/test-hidden-layers.json",
+    "expect": {
+      "pass": true,
+      "check_ids": ["hidden-layers"]
+    },
+    "source": "hand-built",
+    "notes": "#115 regression: five OCMDs (AllOn, AnyOn, AllOff, AnyOff, VE) over groups with opposite View and Print usage, on Form XObjects and marked content. Screen and print show different content; the scan passed it clean before membership dictionaries were evaluated for both usages."
+  },
   {
     "id": "font-integrity-corrupt",
     "pdf": "font-integrity-corrupt.pdf",