[DemchaAV]

Why

A row column sized to its content (DocumentRowColumn.auto()) is given a point of slack (EDITOR_COLUMN_SLACK_POINTS). An editor setting its text in its own face would otherwise wrap it: a table of contents' label broke mid-word in LibreOffice without it. withRowEditorSlack always took that point out of the row's weight columns. The auto column was written a point wider, and whatever stood right of it moved a point right. Nothing named it.

A rule in a placed row's column also counted its left margin twice. The column already starts past the child's margin (leftMarginInCell), and writeRule added it again as the rule's indent.

Measured on Windows, in Word:

Stroke	Before
ReceiptModern's 8 leaders	start +0.95 to +1.04pt
EditorialProposal's 3 signature lines	start +0.88 to +1.02pt
VioletGrid's credential heading rules	start +12.3pt (their 11.3pt margin again, and the point)
CharcoalGold's heading rules	start +9.25pt (their 9pt margin again)

What changed

• withRowEditorSlack counts the room an auto column already has (roomInItsColumn):
  • The column runs to the next child's start, past that child's left margin, so its text box holds that margin. CharcoalGold's heading words have the 9pt their rule stands in by, and take no point at all.
  • A paragraph's own right side counts as far as it does not write it as an indent. In a cell, a left-to-right paragraph not set right writes its right side 2pt short (EDITOR_SLACK_POINTS). A side a margin below zero pulls out stands at the cell's text, so it counts as nothing. The arithmetic is now one helper, writtenSides, shared with writeParagraph.
• A paragraph set left takes what that leaves from the gap after its column, the column's right margin. The column keeps the page's width, and what stands right of it stays where the page sets it.
  • The row's padding after its last column is not a gap: a painted row's panel takes it out of its columns (withoutTheRowsPadding).
  • A paragraph set otherwise, or a child that is not a paragraph, takes none from a gap. Set right, a paragraph in an auto column claims its row's whole width on the page.
• What neither holds still comes out of the weight columns, in proportion to their text boxes as before, and the row is named (right end). The note is skipped where the weight columns giving it hold only spacers, or the remainder is under a tenth of a point. Twenty corpus rows are named that nothing named before:
  • ReceiptModern's amounts at the row's end, 0.84 to 1.1pt left in Word and 0.86 to 1.02pt in LibreOffice;
  • VioletGrid's section heading rules, a point right;
  • SerifHeadline's section headings, Orange Ops' contact strip and Subscription's masthead.
• writeRule counts a rule's left margin once in a placed row's column.
• Docs:
  • the recipe's "Row columns" row and its rules paragraph;
  • the CHANGELOG (Public API);
  • the node and value ledgers' row columns entries (ROW_AUTO_ROOM).

Verification

• DocxEditorSlackTest (+10 new, 3 updated):
  • New:
    • a neighbour's 9pt margin needs no point;
    • with no gap, the point comes from the weight column, named;
    • a 0.4pt gap gives what it has;
    • a section takes none from the gap;
    • a centred paragraph takes none from the gap;
    • a paragraph's own right side gives the room it does not indent: 3pt needs no point, 0.4pt leaves 0.6pt to the weight column;
    • a right side a margin below zero pulls out gives no room, beside a neighbour standing in by as much;
    • the row's padding is no gap;
    • a spacer's column is not named;
    • a 0.05pt remainder is not named.
  • Updated:
    • the table of contents' entry: the label's point comes out of the 6pt gap, and the page number's out of the leader, named;
    • the fixed-column test now runs with no gap;
    • the proportion test now puts its auto column at the row's end.
• DocxRuleTest (+1): a rule with a 9pt margin in a row's column starts and ends at Word's reach in from its cell's text.
• Fail-closed: 12 sabotages, each run alone, all caught. A thirteenth cannot change the output: taking a paragraph's whole right side as room, where a side wider than 2pt already gives 2pt, more than the point. The caught ones:
  • room not counted;
  • gap not used;
  • padding taken as a gap;
  • any child, or any paragraph, taking from the gap;
  • a paragraph's spared right side not counted;
  • a side pulled out taken as room;
  • a spacer's column named;
  • under a tenth named;
  • nothing named;
  • the rule's margin counted again;
  • weight columns giving by width.
• Word and LibreOffice on Windows, the changed documents against the export before:
  • In Word, the leaders start within 0.06pt of the page's and end within 0.06pt. The signature lines are within 0.18pt, and VioletGrid's credential rules within 0.07pt.
  • CharcoalGold's heading rules stand with their words, which stand 0.7pt left in both editors.
  • LibreOffice sets each end of a rule 1.4 and 1.5pt in, as before.
  • No word changes or moves down in either editor. EditorialProposal's "Date:" stands 0.17pt right of the page's in Word, where it stood 0.19pt left.
• Corpus: 4 of 62 DOCX change (cv-charcoal_gold, cv-violet_grid, proposal-editorial, receipt-modern). Notes go from 1365 to 1385.
• Gate:
  • ./mvnw -B -ntp clean verify -pl <core, render-pdf, render-docx, render-pptx, templates, testing, qa, coverage> -am → BUILD SUCCESS: core 821, render-pdf 339, render-docx 2083, testing 5, render-pptx 142, templates 127, qa 1828.
  • The JDK 17 knowledge checks pass, and core javadoc has 0 warnings.
  • ./mvnw -f examples/pom.xml test → BUILD SUCCESS, 93 tests. The committed word-export-companion.docx does not change.

Notes for review:

• A row composed in a table cell has no placed children, so its auto columns count no room. They take the point from the gap or the weight columns, as a placed row's would with no neighbour margin.
• An auto column holding no text, such as a spacer or a picture, is still given the point, as before. Where its weight column gives it, the note speaks of "their text".

Lane: shared-engine (render-docx): no public API change.