Adopt upstream PR #2851: Fix boolean read val error for strike tags

[protobi-pieter]

Summary

Adopt upstream PR exceljs#2851 to fix parsing of boolean XML attributes with explicit val="0".

Currently, the code doesn't handle <strike val="0"/> correctly - it always sets the model to true. This fix properly checks the val attribute and sets model to false when val="0".

Upstream PR

• PR: fix boolean read val error like as ：<strike val="0"/> exceljs/exceljs#2851
• Author: @Jason33Wang (Jason233Wang)
• Created: 2024-11-26
• Status: Open in upstream

Changes

File modified:

• lib/xlsx/xform/simple/boolean-xform.js - Fix parseOpen to check val attribute (1 line)

Total: 1 addition, 1 deletion

Bug Description

When reading Excel files with strike-through formatting that is explicitly disabled (<strike val="0"/>), the parser incorrectly interprets it as strike-through enabled.

Current behavior:

parseOpen(node) {
  if (node.name === this.tag) {
    this.model = true;  // Always true!
  }
}

Fixed behavior:

parseOpen(node) {
  if (node.name === this.tag) {
    this.model = node.attributes.val !== "0";  // Respects val attribute
  }
}

Value Proposition

• Low Risk - Single line change in boolean parsing
• Bug Fix - Corrects incorrect parsing behavior
• Standards Compliant - Properly handles OOXML boolean attributes

Testing Plan

• Apply changes from upstream PR
• Run existing test suite
• Verify boolean attributes parse correctly

[protobi-pieter]

✅ Complete

This issue was successfully resolved in commit daa210b on November 7, 2025.

Changes Applied

The fix from upstream PR #2851 was applied to lib/xlsx/xform/simple/boolean-xform.js:

parseOpen(node) {
  if (node.name === this.tag) {
    this.model = node.attributes.val !== '0';  // ✅ Now correctly checks val attribute
  }
}

This properly handles <strike val="0"/> and other boolean XML attributes that explicitly set val="0".

Testing

• ✅ All existing tests pass
• ✅ Code merged to master branch
• ✅ Pushed to remote repository

Checklist Status

• Apply changes from upstream PR
• Run existing test suite
• Verify boolean attributes parse correctly

This issue can now be closed.