xlsx/chart-bar

Metadata

XPath assertions

Render assertions

Generator source

scripts/gen_chart_bar.py

#!/usr/bin/env python3
"""Generate ``fixtures/xlsx/chart-bar.xlsx``.

A minimal one-sheet workbook with a three-row data table
(Q1/10, Q2/20, Q3/30) and a BarChart anchored at D1 bound to
that data. python-xlsx's BarChart emits a <c:barChart> with
<c:barDir val='col'/> (vertical columns) by default. Designed
to satisfy the assertions in ``features/xlsx/chart-bar.json``.
"""

from __future__ import annotations

from pathlib import Path

from xlsx import Workbook
from xlsx.chart import BarChart, Reference

import datetime as _dt
_REPRODUCIBLE_DT = _dt.datetime(2000, 1, 1, 0, 0, 0)

_REPO_ROOT = Path(__file__).resolve().parent.parent
_OUT = _REPO_ROOT / "fixtures" / "xlsx" / "chart-bar.xlsx"


def main() -> int:
    wb = Workbook()
    ws = wb.active
    ws["A1"] = "Q1"
    ws["B1"] = 10
    ws["A2"] = "Q2"
    ws["B2"] = 20
    ws["A3"] = "Q3"
    ws["B3"] = 30

    chart = BarChart()
    data = Reference(ws, min_col=2, min_row=1, max_row=3)
    cats = Reference(ws, min_col=1, min_row=1, max_row=3)
    chart.add_data(data, titles_from_data=False)
    chart.set_categories(cats)
    ws.add_chart(chart, "D1")

    _OUT.parent.mkdir(parents=True, exist_ok=True)
    wb.save(_OUT, zip_date_time=_REPRODUCIBLE_DT)
    print(_OUT)
    return 0


if __name__ == "__main__":
    raise SystemExit(main())

Manifest (expanded)

{
  "$schema": "../manifest.schema.json",
  "id": "xlsx/chart-bar",
  "title": "Bar / column chart",
  "format": "xlsx",
  "category": "charts",
  "summary": "A BarChart added via ws.add_chart(...) on a worksheet produces a xl/charts/chart1.xml part whose <c:plotArea> carries a <c:barChart> with a <c:barDir val='col'/> (default orientation — python-xlsx emits a vertical column chart for BarChart).",
  "spec": {
    "source": "ecma-376-5-part-1",
    "clause": "21.2.2.16",
    "element": "c:barChart",
    "rnc_reference": "spec/ecma-376-5/part-1/rnc/DrawingML.rnc",
    "xsd_reference": "spec/ecma-376-5/part-1/xsd/dml-chart.xsd",
    "notes": "ECMA-376 Part 1 clause 21.2.2.16 defines <c:barChart>; its child <c:barDir val='bar'/> means horizontal (rows/bars) and val='col' means vertical (columns). Both shapes share the <c:barChart> element — the orientation is carried by <c:barDir>. python-xlsx's `from xlsx.chart import BarChart` defaults to vertical columns (barDir='col'), matching the openpyxl lineage. The XPath below accepts either 'bar' or 'col' so the assertion is robust across writer choices, but records the observed python-xlsx value in the sibling xl/charts/chart1.xml fixture."
  },
  "fixtures": {
    "machine": "xlsx/chart-bar",
    "office": "xlsx/chart-bar"
  },
  "generator": {
    "python": "scripts/gen_chart_bar.py"
  },
  "assertions": [
    {
      "id": "chart-bar-direction",
      "part": "xl/charts/chart1.xml",
      "namespaces": {
        "c": "http://schemas.openxmlformats.org/drawingml/2006/chart"
      },
      "xpath": "//c:barChart/c:barDir[@val='bar' or @val='col']",
      "must": "exist",
      "description": "The chart part must carry <c:barChart>/<c:barDir> with val='bar' or val='col'. Both are spec-valid orientations of a bar chart; python-xlsx emits 'col' (vertical columns) for its BarChart default."
    },
    {
      "id": "chart-bar-series-value-ref",
      "part": "xl/charts/chart1.xml",
      "namespaces": {
        "c": "http://schemas.openxmlformats.org/drawingml/2006/chart"
      },
      "xpath": "//c:barChart/c:ser/c:val/c:numRef/c:f",
      "must": "exist",
      "description": "The bar chart must have at least one series whose <c:val> points at a worksheet range via <c:numRef>/<c:f>. This confirms the chart is wired to sheet data, not an embedded literal cache."
    }
  ],
  "render_assertions": [
    {
      "id": "chart-bar-rendered",
      "kind": "css_selector",
      "selector": ".chart, [data-chart-type='bar'], [data-chart-type='column'], [data-kind='chart'], svg.chart, .xlsx-chart",
      "must": "exist",
      "description": "A DOM node marked as a chart must be rendered. Most current xlsxjs-style renderers do not implement chart rendering — this assertion is expected to fail for those libraries and is the canonical fork signal."
    },
    {
      "id": "sheet-count",
      "kind": "css_selector",
      "selector": "section.xlsx",
      "must": "equal-count",
      "count": 1,
      "description": "Exactly one rendered sheet section. Catches renderers that emit zero sheets (hard failure) or duplicate a sheet."
    }
  ]
}