Fix html_reports feature

[WaterWhisperer]

Fixes #56

[Copilot]

Pull request overview

Note

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This PR restores html_reports as the switch that actually controls HTML report generation, making HTML-report-related deps truly optional and updating docs/tests to reflect the default-feature behavior.

Changes:

• Gate HTML-report code paths behind feature = "html_reports" and make criterion-plot/tinytemplate optional deps enabled by that feature.
• Add a regression test to ensure disabling html_reports prevents report/ output.
• Update README/book docs and changelog to reflect the feature/defaults behavior.

Reviewed changes

Copilot reviewed 8 out of 8 changed files in this pull request and generated 5 comments.

Show a summary per file

File	Description
tests/criterion_tests.rs	Adds a feature-gated regression test for absence of HTML report output.
src/report.rs	Guards the HTML reporter field and invocation behind html_reports.
src/lib.rs	Gates plotting modules/APIs behind html_reports and adds no-op APIs when disabled.
book/src/user_guide/plots_and_graphs.md	Updates guidance/examples around enabling/disabling HTML reports.
book/src/user_guide/html_report.md	Updates guidance/examples around enabling/disabling HTML reports.
README.md	Simplifies dependency snippet now that HTML reports are default-enabled.
Cargo.toml	Makes HTML-report deps optional and adds html_reports to default features.
CHANGELOG.md	Notes fix restoring html_reports control over report generation.

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[lemmih]

Making 'html_reports' a default feature goes beyond just fixing it. How about we add tests for the feature while keeping it non-default?

[WaterWhisperer]

Making 'html_reports' a default feature goes beyond just fixing it. How about we add tests for the feature while keeping it non-default?

Thanks for clarifying. I treated the issue suggestion’s “enable it by default” as part of the fix, I'll update it.

[Copilot]

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