fix: relative base URL double-prefix and skipped inline styles

[cossssmin]

Two more relative-base bugs in the base URL transformer, both surfaced with a relative url.base (e.g. /images/) and masked by absolute bases — an absolute base becomes absolute after one prepend, so isAbsoluteUrl self-guards. Follow-up to #1825 (the infinite-loop fix), same file.

1. VML src double-prefixed inside MSO comments

A v:image/v:fill src inside an MSO conditional comment is rewritten by both rewriteVMLs and rewriteMsoComments' generic src= pass. With a relative base neither pass sees the value as absolute, so it's prepended twice:

<v:fill src="hero.jpg"> → src="/images//images/hero.jpg"

Fix: guard the MSO/VML passes with startsWith(url) so an already-prefixed src (from the first pass) is left alone. Absolute bases keep self-guarding via isAbsoluteUrl.

2. Inline style url() skipped when tags is restricted

The inline-style url() rewrite sat inside the tags-filter gate, so tags: ['img'] skipped a background image on any non-listed tag:

<td style="background-image: url(bg.jpg)"> → unchanged

The tags filter is meant to restrict source attributes (src/href/…), not CSS url() rewriting — which is governed by inlineCss (mirroring how <style> tags are handled). Fix: move the inline-style rewrite out of the tag gate.

Tests

Added regression tests (relative base): v:fill/v:image in MSO comments prefixed exactly once (no /images//images/), and inline style url() still rewritten under tags: ['img']. Full suite green (1772), lint clean.

Summary by CodeRabbit

• Bug Fixes
  • Fixed inline CSS URLs so they are consistently rewritten, including on restricted tags.
  • Prevented duplicate base URLs in VML and MSO comment image sources.
  • Preserved tag filtering for supported source attributes.
  • Improved handling of similar paths, ensuring only the intended base URL is applied.

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

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Reviewing files that changed from the base of the PR and between 00a9b04 and 18a4f1e.

📒 Files selected for processing (2)

• src/tests/transformers/base.test.ts
• src/transformers/base.ts

🚧 Files skipped from review as they are similar to previous changes (2)

• src/transformers/base.ts
• src/tests/transformers/base.test.ts

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📝 Walkthrough

Walkthrough

The transformer now rewrites inline CSS URLs independently of tag filtering. VML and MSO comment processing avoids duplicate relative base URLs. Regression tests cover restricted tags and v:fill and v:image sources.

Changes

URL rewriting behavior

Layer / File(s)	Summary
Inline style and tag filtering src/transformers/base.ts, src/tests/transformers/base.test.ts	Inline CSS URL rewriting now depends only on inlineCss. Other source attributes still depend on the tags filter.
VML and MSO base URL handling src/transformers/base.ts, src/tests/transformers/base.test.ts	VML and MSO comment rewrites skip URLs that already contain the configured base. Tests cover v:fill, v:image, and boundary-aware paths such as /images2.

Estimated code review effort: 3 (Moderate) | ~20 minutes

Possibly related PRs

• maizzle/framework#1825: Both PRs update CSS URL rewriting for relative base URLs and add regression tests.

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title clearly summarizes the two main fixes: duplicate relative base prefixes and skipped inline styles.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

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Actionable comments posted: 1

🤖 Prompt for all review comments with AI agents

Verify each finding against current code. Fix only still-valid issues, skip the
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Inline comments:
In `@src/transformers/base.ts`:
- Around line 262-267: Update the URL-prefix checks in the VML rewrite
callbacks, including the v:fill and v:image handling, so a source is skipped
only when it matches the configured base path at a path boundary rather than
merely sharing its string prefix; preserve absolute-URL handling and support
bases without a trailing slash. Add regression coverage for both VML elements
using a base such as /images and sources under /images2, ensuring they are
rewritten.

🪄 Autofix (Beta)

Fix all unresolved CodeRabbit comments on this PR:

• Push a commit to this branch (recommended)
• Create a new PR with the fixes

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ℹ️ Review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: CHILL

Plan: Pro Plus

Run ID: 9d76d8e8-0b0a-4214-a932-0e148fb093f1

📥 Commits

Reviewing files that changed from the base of the PR and between 6a4ffd1 and 00a9b04.

📒 Files selected for processing (2)

• src/tests/transformers/base.test.ts
• src/transformers/base.ts