Fixed silent data loss when parsing DCC documents

[HassanAkbar]

Reading a DCC file and writing it back silently dropped measurements. This fixes the six causes.

On dcclib/valid.xml, 8 of 13 quantities and the entire measurement list disappeared,
and the document still validated. The test suite stayed green because
round_trip_spec.rb only asserted the output was a String containing one word.

What was wrong:

• Dcc::V3 overwrote its own :list model with the D-SI one when re-exporting types.
• D-SI v1 expandedUnc and coverageInterval were never wired into si:real.
• dcc:mathml was mapped onto Mml::V3::Math directly instead of through its
  dcc:xmlType wrapper, so it never parsed.
• DecimalXmlList serialized one list into N elements holding Ruby array literals.
• A Schematron rule rejected the single-uncertainty broadcast that PTB's own reference
  documents use.

Breaking: formula.mathml returns a Dcc::V2::Mathml / Dcc::V3::Mathml wrapper
instead of an Mml::V3::Math. Callers now read formula.mathml.math.

Known and accepted:

• lib/dcc/diff.rb is touched although it is not a parsing fix. Dcc::Diff raised
  NoMethodError on the new value object; it now treats anything it cannot descend
  into as a leaf, which closes the class rather than special-casing one type.
• Values#== accepts a plain Array but eql? does not. That is deliberate: eql? is
  what Hash uses and must stay strict.
• Quantities nested under dcc:statement or measurementMetaData are still dropped —
  dcc:data is unmapped on Dcc::Base::Statement. Separate bug, documented in the spec.
• Four inline rubocop:disable in the D-SI mapping modules. Around twenty sibling
  modules exceed the same metrics and are exempted by file; keeping these four shaped
  like their siblings beats making them diverge.

[Copilot]

Pull request overview

Fixes multiple causes of silent data loss when round-tripping DCC documents by correcting model registrations/mappings (DCC vs D-SI and MathML) and by fixing decimal XML list serialization, backed by new fidelity-focused specs.

Changes:

• Prevent D-SI type re-export from overwriting DCC’s own :list registration and add missing D-SI expandedUnc / coverageInterval wiring under si:real.
• Introduce dcc:mathml as a proper dcc:xmlType wrapper model (breaking API change: formula.mathml.math).
• Fix decimal XML list casting/serialization to preserve space-separated wire form and avoid scientific notation leakage; expand tests to catch regressions.

Reviewed changes

Copilot reviewed 25 out of 25 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
spec/parse_fidelity_spec.rb	Adds end-to-end round-trip element-count assertions to detect silent parse/serialize data loss.
spec/dcc/validate/schematron_spec.rb	Adds specs for broadcast-vs-per-value uncertainty list consistency validation.
spec/dcc/type_spec.rb	Adds tests for DecimalXmlList value-object behavior (equality, enumeration, YAML, attribute round-trip).
spec/dcc/convert/additional_spec.rb	Ensures CSV conversion doesn’t emit scientific notation for list values.
lib/dcc/validate/schematron/rules/uncertainty_consistency.rb	Extends rule to validate multiple uncertainty-related lists and allow broadcast semantics.
lib/dcc/v3/mathml.rb	Adds DCC v3 Mathml wrapper model registered as :mathml.
lib/dcc/v3.rb	Autoloads/registers Mathml; prevents D-SI re-export from overwriting DCC-owned model IDs (notably :list).
lib/dcc/v2/mathml.rb	Adds DCC v2 Mathml wrapper model registered as :mathml.
lib/dcc/v2.rb	Autoloads/registers Mathml in v2 element set.
lib/dcc/type/decimal_xml_list.rb	Reworks decimal XML list type into a value object to preserve wire format and correct serialization.
lib/dcc/si/v2/expanded_unc.rb	Adds D-SI v2 ExpandedUnc model registered as :expandedUnc.
lib/dcc/si/v2/coverage_interval.rb	Adds D-SI v2 CoverageInterval model registered as :coverageInterval.
lib/dcc/si/v2.rb	Autoloads/registers new v2 uncertainty models.
lib/dcc/si/v1/expanded_unc.rb	Refactors v1 ExpandedUnc to share base mapping module.
lib/dcc/si/v1/coverage_interval.rb	Adds D-SI v1 CoverageInterval model registered as :coverageInterval.
lib/dcc/si/v1.rb	Autoloads/registers v1 CoverageInterval.
lib/dcc/si/base/real.rb	Maps deprecated expandedUnc and coverageInterval under si:real.
lib/dcc/si/base/expanded_unc.rb	Introduces shared mapping for si:expandedUncType.
lib/dcc/si/base/coverage_interval.rb	Introduces shared mapping for si:coverageIntervalType.
lib/dcc/si/base.rb	Autoloads shared uncertainty base modules.
lib/dcc/diff.rb	Adjusts diff “primitive” detection to treat unknown value objects as leaf nodes.
lib/dcc/convert/csv.rb	Uses decimal list wire serialization for CSV output to avoid scientific notation.
lib/dcc/base/mathml.rb	Introduces shared DCC dcc:mathml wrapper mapping around ml:math.
lib/dcc/base/formula.rb	Changes formula.mathml from Mml::V3::Math to :mathml wrapper type.
CHANGELOG.adoc	Documents fixes and the breaking change for MathML wrapper behavior.

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[Copilot]

Pull request overview

Copilot reviewed 25 out of 25 changed files in this pull request and generated no new comments.

Suppressed comments (1)

spec/parse_fidelity_spec.rb:52

• The new round-trip assertions for dcc:list only verify that the wrapper elements survive. If a regression causes dcc:list to parse as an empty list again, the list count can still match while nested dcc:quantity elements are silently dropped (which is the failure mode described for dcclib/valid.xml). Consider also asserting quantity counts for dcclib/valid.xml to lock in the original bug fix.

  describe "dcc:quantity" do
    it "round-trips every quantity in dcc_excel/example.xml" do
      expect(counts("dcc_excel/example.xml", "quantity")).to eq(in: 20, out: 20)
    end
  end

[Copilot]

Pull request overview

Copilot reviewed 25 out of 25 changed files in this pull request and generated no new comments.

[Copilot]

Pull request overview

Copilot reviewed 28 out of 28 changed files in this pull request and generated no new comments.