Fix html_reports feature

CHANGELOG.md

@@ -7,6 +7,10 @@ and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.
 
 ## [Unreleased]
 
+### Fixed
+
+- Make the non-default `html_reports` feature control HTML report generation again.
+
 ## [0.8.2](https://github.com/criterion-rs/criterion.rs/compare/criterion-v0.8.1...criterion-v0.8.2) - 2026-02-04
 
 ### Fixed

Cargo.toml

@@ -36,15 +36,15 @@ exclude = ["book/*"]
 
 [dependencies]
 anes = "0.1.4"
-criterion-plot = { path = "plot", version = "0.8.2" }
+criterion-plot = { path = "plot", version = "0.8.2", optional = true }
 itertools = "0.13"
 page_size = "0.6"
 serde = { version = "1.0.100", features = ["derive"] }
 serde_json = "1.0.100"
 ciborium = "0.2.0"
 clap = { version = "4.5", default-features = false, features = ["std", "help"] }
 walkdir = "2.3"
-tinytemplate = "1.1"
+tinytemplate = { version = "1.1", optional = true }
 cast = "0.3"
 num-traits = { version = "0.2", default-features = false, features = ["std"] }
 oorandom = "11.1"
@@ -106,7 +106,7 @@ async_smol = ["dep:smol", "async"]
 async_tokio = ["dep:tokio", "async"]
 
 # Make Criterion.rs generate its own plots (as opposed to using cargo-criterion)
-html_reports = []
+html_reports = ["dep:criterion-plot", "dep:tinytemplate"]
 
 # Make Criterion.rs usable outside of cargo-criterion.
 cargo_bench_support = []

book/src/user_guide/html_report.md

@@ -1,10 +1,12 @@
 # HTML Report
 
-Starting with Criterion.rs 0.4.0 HTML reports must be explicitly enabled via the `html_reports` [feature](https://doc.rust-lang.org/cargo/reference/features.html#dependency-features):
+HTML reports must be explicitly enabled via the `html_reports` [feature](https://doc.rust-lang.org/cargo/reference/features.html#dependency-features):
+
 ```toml
 [dev-dependencies]
-criterion = { version = "0.5", features = ["html_reports"] }
+criterion = { version = "0.8", features = ["html_reports"] }
 ```
+
 Criterion.rs can generate an HTML report displaying the results of the benchmark under
 `target/criterion/reports/index.html`. By default, the plots are generated using
 [gnuplot](http://www.gnuplot.info/) if it is available, or the

book/src/user_guide/plots_and_graphs.md

@@ -6,12 +6,11 @@ understanding of the behavior of the benchmark. These charts will be generated w
 it is not available. The examples below were generated using the gnuplot backend, but the plotters
 ones are similar.
 
-Note that in older versions of criterion.rs html reports were enabled by default. Recent versions
-have introduced a cargo feature for plot and html generation. In order to activate the html report
-generation make sure that your `Cargo.toml` activates the feature:
+HTML reports and plot generation are controlled by the non-default `html_reports` feature. Enable it
+in your `Cargo.toml` to generate HTML reports:
 
 ```toml
-criterion = { version = "0.5", features = ["html_reports"] }
+criterion = { version = "0.8", features = ["html_reports"] }
 ```
 
 ## File Structure

src/lib.rs

@@ -48,10 +48,12 @@ mod error;
 mod estimate;
 mod format;
 mod fs;
+#[cfg(feature = "html_reports")]
 mod html;
 mod kde;
 mod macros;
 pub mod measurement;
+#[cfg(feature = "html_reports")]
 mod plot;
 pub mod profiler;
 mod report;
@@ -70,19 +72,20 @@ use std::{
     time::Duration,
 };
 
-use {
-    criterion_plot::{Version, VersionError},
-    std::sync::OnceLock,
-};
+#[cfg(feature = "html_reports")]
+use criterion_plot::{Version, VersionError};
+use std::sync::OnceLock;
 
-#[cfg(feature = "plotters")]
+#[cfg(feature = "html_reports")]
+use crate::html::Html;
+#[cfg(all(feature = "html_reports", feature = "plotters"))]
 use crate::plot::PlottersBackend;
+#[cfg(feature = "html_reports")]
+use crate::plot::{Gnuplot, Plotter};
 use crate::{
     benchmark::BenchmarkConfig,
     connection::{Connection, OutgoingMessage},
-    html::Html,
     measurement::{Measurement, WallTime},
-    plot::{Gnuplot, Plotter},
     profiler::{ExternalProfiler, Profiler},
     report::{BencherReport, CliReport, CliVerbosity, Report, ReportContext, Reports},
 };
@@ -94,12 +97,14 @@ pub use crate::{
     benchmark_group::{BenchmarkGroup, BenchmarkId},
 };
 
+#[cfg(feature = "html_reports")]
 fn gnuplot_version() -> &'static Result<Version, VersionError> {
     static GNUPLOT_VERSION: OnceLock<Result<Version, VersionError>> = OnceLock::new();
 
     GNUPLOT_VERSION.get_or_init(criterion_plot::version)
 }
 
+#[cfg(feature = "html_reports")]
 fn default_plotting_backend() -> &'static PlottingBackend {
     static DEFAULT_PLOTTING_BACKEND: OnceLock<PlottingBackend> = OnceLock::new();
 
@@ -278,6 +283,7 @@ pub enum PlottingBackend {
     /// Null plotting backend which outputs nothing,
     None,
 }
+#[cfg(feature = "html_reports")]
 impl PlottingBackend {
     fn create_plotter(&self) -> Option<Box<dyn Plotter>> {
         match self {
@@ -405,6 +411,7 @@ impl Default for Criterion {
             cli: CliReport::new(false, false, CliVerbosity::Normal),
             bencher_enabled: false,
             bencher: BencherReport,
+            #[cfg(feature = "html_reports")]
             html: default_plotting_backend().create_plotter().map(Html::new),
             csv_enabled: cfg!(feature = "csv_output"),
         };
@@ -442,7 +449,10 @@ impl Default for Criterion {
             criterion.report.cli_enabled = false;
             criterion.report.bencher_enabled = false;
             criterion.report.csv_enabled = false;
-            criterion.report.html = None;
+            #[cfg(feature = "html_reports")]
+            {
+                criterion.report.html = None;
+            }
         }
         criterion
     }
@@ -487,6 +497,7 @@ impl<M: Measurement> Criterion<M> {
     /// Panics if `backend` is [`PlottingBackend::Gnuplot`] and `gnuplot` is not available.
     ///
     /// [plotting backend]: PlottingBackend
+    #[cfg(feature = "html_reports")]
     pub fn plotting_backend(mut self, backend: PlottingBackend) -> Criterion<M> {
         if let PlottingBackend::Gnuplot = backend {
             assert!(
@@ -501,6 +512,16 @@ impl<M: Measurement> Criterion<M> {
         self
     }
 
+    #[must_use]
+    /// Set the plotting backend.
+    ///
+    /// This has no effect when Criterion.rs is built without the `html_reports` feature.
+    #[cfg(not(feature = "html_reports"))]
+    pub fn plotting_backend(self, backend: PlottingBackend) -> Criterion<M> {
+        let _ = backend;
+        self
+    }
+
     #[must_use]
     /// Changes the default size of the sample for benchmarks run with this runner.
     ///
@@ -641,6 +662,7 @@ impl<M: Measurement> Criterion<M> {
 
     #[must_use]
     /// Enables plotting
+    #[cfg(feature = "html_reports")]
     pub fn with_plots(mut self) -> Criterion<M> {
         // If running under cargo-criterion then don't re-enable the reports; let it do the reporting.
         if self.connection.is_none() && self.report.html.is_none() {
@@ -654,13 +676,32 @@ impl<M: Measurement> Criterion<M> {
         self
     }
 
+    #[must_use]
+    /// Enables plotting.
+    ///
+    /// This has no effect when Criterion.rs is built without the `html_reports` feature.
+    #[cfg(not(feature = "html_reports"))]
+    pub fn with_plots(self) -> Criterion<M> {
+        self
+    }
+
     #[must_use]
     /// Disables plotting
+    #[cfg(feature = "html_reports")]
     pub fn without_plots(mut self) -> Criterion<M> {
         self.report.html = None;
         self
     }
 
+    #[must_use]
+    /// Disables plotting.
+    ///
+    /// This has no effect when Criterion.rs is built without the `html_reports` feature.
+    #[cfg(not(feature = "html_reports"))]
+    pub fn without_plots(self) -> Criterion<M> {
+        self
+    }
+
     #[must_use]
     /// Names an explicit baseline and enables overwriting the previous results.
     pub fn save_baseline(mut self, baseline: String) -> Criterion<M> {
@@ -1057,7 +1098,10 @@ https://criterion-rs.github.io/book/faq.html
             self.report.cli_enabled = false;
             self.report.bencher_enabled = false;
             self.report.csv_enabled = false;
-            self.report.html = None;
+            #[cfg(feature = "html_reports")]
+            {
+                self.report.html = None;
+            }
         } else {
             match matches.get_one("output-format").map(String::as_str) {
                 Some("bencher") => {

src/report.rs

@@ -1,8 +1,10 @@
 #[cfg(feature = "csv_output")]
 use crate::csv_report::FileCsvReport;
+#[cfg(feature = "html_reports")]
+use crate::html::Html;
 use crate::stats::bivariate::regression::Slope;
+use crate::stats::bivariate::Data;
 use crate::stats::univariate::outliers::tukey::LabeledSample;
-use crate::{html::Html, stats::bivariate::Data};
 
 use crate::estimate::{ChangeDistributions, ChangeEstimates, Distributions, Estimate, Estimates};
 use crate::format;
@@ -319,6 +321,7 @@ pub(crate) struct Reports {
     pub(crate) bencher_enabled: bool,
     pub(crate) bencher: BencherReport,
     pub(crate) csv_enabled: bool,
+    #[cfg(feature = "html_reports")]
     pub(crate) html: Option<Html>,
 }
 macro_rules! reports_impl {
@@ -334,6 +337,7 @@ macro_rules! reports_impl {
             if self.csv_enabled {
                 FileCsvReport.$name($($argn),*);
             }
+            #[cfg(feature = "html_reports")]
             if let Some(reporter) = &self.html {
                 reporter.$name($($argn),*);
             }

tests/criterion_tests.rs

@@ -137,6 +137,18 @@ fn test_without_plots() {
     }
 }
 
+#[cfg(all(feature = "plotters", not(feature = "html_reports")))]
+#[test]
+fn test_plotters_without_html_reports_does_not_generate_report() {
+    let dir = temp_dir();
+    short_benchmark(&dir).bench_function("test_html_reports_disabled", |b| b.iter(|| 10));
+
+    let benchmark_dir = dir.path().join("test_html_reports_disabled");
+    verify_stats(&benchmark_dir, "new");
+    verify_stats(&benchmark_dir, "base");
+    verify_not_exists(&benchmark_dir, "report");
+}
+
 #[test]
 fn test_save_baseline() {
     let dir = temp_dir();