Document.fonts misses fonts nested in Type 3 and Pattern resources

[lin-string]

Summary

Document.fonts only discovers fonts directly listed in each page's Font resources. Fonts reachable through nested resource dictionaries are omitted, including fonts inside Type 3 fonts and Pattern resources.

Versions tested

• playa-pdf 1.1.0 (v1.1.0, commit 85a9c1e22e327bf873e4282d66ed1dba89fa7575)
• Current main at commit 9496dfea5150343c9dc05544d9c004bbcccf17e6, checked on 2026-09-06

Test files

• FontinsideType3insideType3.pdf, with expected behavior described in the PDF Association test documentation.
• PatternTextInsideText.pdf, with expected behavior described in the PDF Association test documentation.

Reproduction

import playa

for path in (
    "FontinsideType3insideType3.pdf",
    "PatternTextInsideText.pdf",
):
    with playa.open(path) as document:
        print(path, list(document.fonts))

Actual behavior

The nested Type 3 fixture reports only ['FType3A']; it omits FType3B and Helvetica. The Pattern fixture reports only ['Helvetica']; it omits Times-Italic.

Expected behavior

Document-wide font discovery should recursively traverse reachable resource dictionaries. The nested Type 3 fixture should report FType3A, FType3B, and Helvetica, while the Pattern fixture should report Helvetica and Times-Italic.

Relevant implementation

document.FontMapping._iteritems() builds its mapping exclusively from page.fonts.values(). It does not traverse resource dictionaries reachable through Type 3 fonts, Patterns, or other nested resources.

Disclosure

This issue was prepared by an AI coding agent on behalf of @lin-string. The reproduction and results were verified against the current default branch.