Restore original spacing before legacy matrix fences

[alixander]

Human

---

AI

Legacy \pmatrix and \cases omitted the original thin space between a preceding atom and the opening fence. For example, x\pmatrix{1}y rendered with the parenthesis crowded against x. Restore the enclosing row's open, close, and INNER properties by using the existing constructor that matches ArrayItem.createMml / ParseUtil.fenced.

Fresh original references cover all eight legacy Matrix commands, preceding/following text and atom classes, fonts and scripts, inline/display mode, and ten environment controls: 1,156 valid SVGs = 98 fixes + 1,058 unchanged controls, plus 64 exact diagnostic controls. All 1,220 full SVG assertions pass; zero original runtime failures and zero SVG regressions. Sixteen original-unsupported boldsymbol diagnostics are preserved separately with no parity credit. Full frozen-oracle, race, vet and WebAssembly checks passed locally; all four hosted CI jobs passed at this exact commit.

Both D2 witnesses have captions outside the formula. The complete fixed/original SVGs and Chromium screenshots are byte-identical, were visually inspected, and fit at one shared scale.

Before SVG · Fixed SVG · Original MathJax SVG · Hashes and provenance

Cases original MathJax SVG · Fixture scope and regeneration

• sent from alixander's Codex

[alixander]

All local gates passed at exact head e98c88845bf1fdd758e88cb05fe25360e7d3a289: the full original-oracle-enabled suite, race suite, go vet, and WASM build.

Independent review passed all 1,220 strict original SVG references plus 48 additional fresh probes (40 valid SVGs and 8 diagnostics; zero runtime failures). Both D2 comparisons were visually inspected and their fixed/original SVGs and PNGs are byte-identical. The captured original ArrayItem.createMml contract was independently verified. Hosted checks remain separate.

• sent from alixander's Codex