Add support for showing other metrics in the terminal

tests/integration_tests.rs

@@ -37,11 +37,51 @@ fn json_snapshot_settings() -> insta::Settings {
 
 #[test]
 fn runs_successfully() {
-    hyperfine()
+    let output = hyperfine()
+        .arg("--metrics=default")
         .arg("--runs=2")
         .arg("echo dummy benchmark")
+        .output()
+        .unwrap();
+    assert!(output.status.success(), "{:?}", output);
+    let stdout = String::from_utf8(output.stdout).unwrap();
+    assert!(stdout.contains("Time"));
+    assert_eq!(stdout.contains("Memory"), !cfg!(windows));
+    assert!(!stdout.contains("Change"));
+    assert!(!stdout.contains("Outliers"));
+}
+
+#[test]
+fn all_metrics_skip_unavailable_counters() {
+    let output = hyperfine_debug()
+        .args([
+            "--metrics=all",
+            "--style=basic",
+            "--runs=2",
+            "sleep 1",
+            "sleep 2",
+        ])
+        .output()
+        .unwrap();
+    assert!(output.status.success(), "{:?}", output);
+    let stdout = String::from_utf8(output.stdout).unwrap();
+    assert_eq!(stdout.matches("Time").count(), 2);
+    assert_eq!(stdout.matches("User time").count(), 2);
+    assert_eq!(stdout.matches("System time").count(), 2);
+    assert_eq!(stdout.contains("Memory"), !cfg!(windows));
+    assert!(!stdout.contains("CPU cycles"));
+    assert!(!stdout.contains("Instructions"));
+    assert!(!stdout.contains("Change vs #1"));
+    assert!(stdout.contains("+100.0%"));
+
+    // Explicit selections still require the metric, unlike the `all` preset.
+    hyperfine_debug()
+        .args(["--metrics=instructions", "--runs=1", "sleep 1"])
         .assert()
-        .success();
+        .failure()
+        .stderr(predicate::str::contains(
+            "Metric 'instructions' is unavailable",
+        ));
 }
 
 #[test]
@@ -117,7 +157,7 @@ fn min_runs_of_one_still_performs_one_run() {
         .arg("sleep 4")
         .assert()
         .success()
-        .stdout(predicate::str::contains("Time (abs ≡)"));
+        .stdout(predicate::str::contains("Benchmark 1: sleep 4 (1 run)"));
 }
 
 #[test]
@@ -159,7 +199,7 @@ fn fails_with_wrong_number_of_prepare_options() {
         .arg("--prepare=echo ref")
         .arg("--prepare=echo a")
         .arg("--prepare=echo b")
-        .arg("--reference=echo ref")
+        .arg("echo ref")
         .arg("echo a")
         .arg("echo b")
         .assert()
@@ -182,7 +222,7 @@ fn fails_with_wrong_number_of_prepare_options() {
         .arg("--runs=1")
         .arg("--prepare=echo a")
         .arg("--prepare=echo b")
-        .arg("--reference=echo ref")
+        .arg("echo ref")
         .arg("echo a")
         .arg("echo b")
         .assert()
@@ -208,7 +248,7 @@ fn fails_with_wrong_number_of_conclude_options() {
         .arg("--conclude=echo ref")
         .arg("--conclude=echo a")
         .arg("--conclude=echo b")
-        .arg("--reference=echo ref")
+        .arg("echo ref")
         .arg("echo a")
         .arg("echo b")
         .assert()
@@ -231,7 +271,7 @@ fn fails_with_wrong_number_of_conclude_options() {
         .arg("--runs=1")
         .arg("--conclude=echo a")
         .arg("--conclude=echo b")
-        .arg("--reference=echo ref")
+        .arg("echo ref")
         .arg("echo a")
         .arg("echo b")
         .assert()
@@ -509,29 +549,27 @@ fn returns_mean_time_in_correct_unit() {
         .arg("sleep 1.234")
         .assert()
         .success()
-        .stdout(predicate::str::contains("Time (mean ± σ):      1.234 s ±"));
+        .stdout(predicate::str::is_match(r"Time\s+1\.234 s\s+±").unwrap());
 
     hyperfine_debug()
         .arg("sleep 0.123")
         .assert()
         .success()
-        .stdout(predicate::str::contains("Time (mean ± σ):     123.0 ms ±"));
+        .stdout(predicate::str::is_match(r"Time\s+123\.0 ms\s+±").unwrap());
 
     hyperfine_debug()
-        .arg("--time-unit=millisecond")
+        .arg("--metrics=time_wall_clock:ms")
         .arg("sleep 1.234")
         .assert()
         .success()
-        .stdout(predicate::str::contains("Time (mean ± σ):     1234.0 ms ±"));
+        .stdout(predicate::str::is_match(r"Time\s+1234\.0 ms\s+±").unwrap());
 
     hyperfine_debug()
-        .arg("--time-unit=microsecond")
+        .arg("--metrics=time_wall_clock:us")
         .arg("sleep 1.234")
         .assert()
         .success()
-        .stdout(predicate::str::contains(
-            "Time (mean ± σ):     1234000.0 µs ±",
-        ));
+        .stdout(predicate::str::is_match(r"Time\s+1234000\.0 µs\s+±").unwrap());
 }
 
 #[test]
@@ -625,32 +663,35 @@ fn takes_both_preparation_and_conclusion_command_into_account_for_computing_numb
 }
 
 #[test]
-fn shows_benchmark_comparison_with_relative_times() {
+fn shows_multiple_metrics_relative_to_first_command() {
     let _settings = snapshot_settings().bind_to_scope();
     assert_cmd_snapshot!(hyperfine_debug()
         .arg("--style=basic")
-        .arg("sleep 1.0")
-        .arg("sleep 2.0")
-        .arg("sleep 3.0"), @r"
+        .arg("--metrics=time_wall_clock:ms,time_user:us,memory_peak_resident:MiB")
+        .arg("sleep 0.0817")
+        .arg("sleep 0.6155")
+        .arg("sleep 0.1707"), @"
     success: true
     exit_code: 0
     ----- stdout -----
-    Benchmark 1: sleep 1.0
-      Time (mean ± σ):      1.000 s ±  0.000 s    [User: 0.000 s, System: 0.000 s]
-      Range (min … max):    1.000 s …  1.000 s    10 runs
+    Benchmark 1: sleep 0.0817 (36 runs)
+                    mean     ±       σ          min     …     max
+      Time          81.7 ms  ±     0.0 ms      81.7 ms  …    81.7 ms
+      User time      0.0 µs  ±     0.0 µs       0.0 µs  …     0.0 µs
+      Memory         0.0 MiB ±     0.0 MiB      0.0 MiB …     0.0 MiB
 
-    Benchmark 2: sleep 2.0
-      Time (mean ± σ):      2.000 s ±  0.000 s    [User: 0.000 s, System: 0.000 s]
-      Range (min … max):    2.000 s …  2.000 s    10 runs
+    Benchmark 2: sleep 0.6155 (10 runs)
+                    mean     ±       σ          min     …     max
+      Time         615.5 ms  ±     0.0 ms     615.5 ms  …   615.5 ms        +653.4%
+      User time      0.0 µs  ±     0.0 µs       0.0 µs  …     0.0 µs            N/A
+      Memory         0.0 MiB ±     0.0 MiB      0.0 MiB …     0.0 MiB           N/A
 
-    Benchmark 3: sleep 3.0
-      Time (mean ± σ):      3.000 s ±  0.000 s    [User: 0.000 s, System: 0.000 s]
-      Range (min … max):    3.000 s …  3.000 s    10 runs
+    Benchmark 3: sleep 0.1707 (17 runs)
+                    mean     ±       σ          min     …     max
+      Time         170.7 ms  ±     0.0 ms     170.7 ms  …   170.7 ms        +108.9%
+      User time      0.0 µs  ±     0.0 µs       0.0 µs  …     0.0 µs            N/A
+      Memory         0.0 MiB ±     0.0 MiB      0.0 MiB …     0.0 MiB           N/A
 
-    Summary
-      sleep 1.0 ran
-        2.00 ± 0.00 times faster than sleep 2.0
-        3.00 ± 0.00 times faster than sleep 3.0
 
     ----- stderr -----
     ");
@@ -660,37 +701,37 @@ fn shows_benchmark_comparison_with_relative_times() {
 fn shows_benchmark_comparison_with_same_time() {
     let _settings = snapshot_settings().bind_to_scope();
     assert_cmd_snapshot!(hyperfine_debug()
+        .arg("--metrics=time_wall_clock,memory_peak_resident")
         .arg("--style=basic")
         .arg("--command-name=A")
         .arg("--command-name=B")
         .arg("sleep 1.0")
         .arg("sleep 1.0")
         .arg("sleep 2.0")
-        .arg("sleep 1000.0"), @r"
+        .arg("sleep 1000.0"), @"
     success: true
     exit_code: 0
     ----- stdout -----
-    Benchmark 1: A
-      Time (mean ± σ):      1.000 s ±  0.000 s    [User: 0.000 s, System: 0.000 s]
-      Range (min … max):    1.000 s …  1.000 s    10 runs
+    Benchmark 1: A (10 runs)
+                 mean     ±       σ          min     …     max
+      Time      1.000 s   ±   0.000 s      1.000 s   …   1.000 s
+      Memory      0.0 B   ±     0.0 B        0.0 B   …     0.0 B
 
-    Benchmark 2: B
-      Time (mean ± σ):      1.000 s ±  0.000 s    [User: 0.000 s, System: 0.000 s]
-      Range (min … max):    1.000 s …  1.000 s    10 runs
+    Benchmark 2: B (10 runs)
+                 mean     ±       σ          min     …     max
+      Time      1.000 s   ±   0.000 s      1.000 s   …   1.000 s            0.0%
+      Memory      0.0 B   ±     0.0 B        0.0 B   …     0.0 B             N/A
 
-    Benchmark 3: sleep 2.0
-      Time (mean ± σ):      2.000 s ±  0.000 s    [User: 0.000 s, System: 0.000 s]
-      Range (min … max):    2.000 s …  2.000 s    10 runs
+    Benchmark 3: sleep 2.0 (10 runs)
+                 mean     ±       σ          min     …     max
+      Time      2.000 s   ±   0.000 s      2.000 s   …   2.000 s         +100.0%
+      Memory      0.0 B   ±     0.0 B        0.0 B   …     0.0 B             N/A
 
-    Benchmark 4: sleep 1000.0
-      Time (mean ± σ):     1000.000 s ±  0.000 s    [User: 0.000 s, System: 0.000 s]
-      Range (min … max):   1000.000 s … 1000.000 s    10 runs
+    Benchmark 4: sleep 1000.0 (10 runs)
+                  mean     ±       σ           min     …      max
+      Time    1000.000 s   ±   0.000 s    1000.000 s   … 1000.000 s       +99900.0%
+      Memory       0.0 B   ±     0.0 B         0.0 B   …      0.0 B             N/A
 
-    Summary
-      A ran
-        As fast (1.00 ± 0.00) as B
-        2.00 ± 0.00 times faster than sleep 2.0
-     1000.00 ± 0.00 times faster than sleep 1000.0
 
     ----- stderr -----
     ");
@@ -700,36 +741,36 @@ fn shows_benchmark_comparison_with_same_time() {
 fn shows_benchmark_comparison_relative_to_reference() {
     let _settings = snapshot_settings().bind_to_scope();
     assert_cmd_snapshot!(hyperfine_debug()
+        .arg("--metrics=time_wall_clock,memory_peak_resident")
         .arg("--style=basic")
-        .arg("--reference=sleep 2.0")
+        .arg("sleep 2.0")
         .arg("sleep 1.0")
-        .arg("sleep 3.0"), @r"
+        .arg("sleep 3.0"), @"
     success: true
     exit_code: 0
     ----- stdout -----
-    Benchmark 1: sleep 2.0
-      Time (mean ± σ):      2.000 s ±  0.000 s    [User: 0.000 s, System: 0.000 s]
-      Range (min … max):    2.000 s …  2.000 s    10 runs
+    Benchmark 1: sleep 2.0 (10 runs)
+                 mean     ±       σ          min     …     max
+      Time      2.000 s   ±   0.000 s      2.000 s   …   2.000 s
+      Memory      0.0 B   ±     0.0 B        0.0 B   …     0.0 B
 
-    Benchmark 2: sleep 1.0
-      Time (mean ± σ):      1.000 s ±  0.000 s    [User: 0.000 s, System: 0.000 s]
-      Range (min … max):    1.000 s …  1.000 s    10 runs
+    Benchmark 2: sleep 1.0 (10 runs)
+                 mean     ±       σ          min     …     max
+      Time      1.000 s   ±   0.000 s      1.000 s   …   1.000 s          -50.0%
+      Memory      0.0 B   ±     0.0 B        0.0 B   …     0.0 B             N/A
 
-    Benchmark 3: sleep 3.0
-      Time (mean ± σ):      3.000 s ±  0.000 s    [User: 0.000 s, System: 0.000 s]
-      Range (min … max):    3.000 s …  3.000 s    10 runs
+    Benchmark 3: sleep 3.0 (10 runs)
+                 mean     ±       σ          min     …     max
+      Time      3.000 s   ±   0.000 s      3.000 s   …   3.000 s          +50.0%
+      Memory      0.0 B   ±     0.0 B        0.0 B   …     0.0 B             N/A
 
-    Summary
-      sleep 2.0 ran
-        2.00 ± 0.00 times slower than sleep 1.0
-        1.50 ± 0.00 times faster than sleep 3.0
 
     ----- stderr -----
     ");
 }
 
 #[test]
-fn command_sorted_comparison_and_markup_identify_reference() {
+fn comparison_and_markup_identify_first_command_as_reference() {
     let _settings = snapshot_settings().bind_to_scope();
     let directory = tempfile::tempdir().unwrap();
     let export_path = directory.path().join("results.md");
@@ -737,34 +778,31 @@ fn command_sorted_comparison_and_markup_identify_reference() {
         .args([
             "--style=basic",
             "--runs=1",
-            "--sort=command",
-            "--reference",
-            "sleep 2",
-            "--reference-name",
-            "baseline",
+            "--command-name=baseline",
             "--export-markdown",
         ])
         .arg(&export_path)
-        .args(["sleep 1", "sleep 2", "sleep 3"])
+        .args(["sleep 2", "sleep 1", "sleep 2", "sleep 3"])
         .output()
         .unwrap();
     assert!(output.status.success(), "{:?}", output);
     let stdout = String::from_utf8(output.stdout).unwrap();
-    let comparison = stdout.split_once("Relative speed comparison\n").unwrap().1;
-    insta::assert_snapshot!(comparison, @r"
-            1.00          baseline (reference)
-            2.00          sleep 1 (faster)
-            1.00          sleep 2 (same speed)
-            1.50          sleep 3 (slower)
-    ");
+    assert!(
+        stdout.contains("Benchmark 1: baseline (1 run)"),
+        "{}",
+        stdout
+    );
+    assert!(stdout.contains("-50.0%"), "{}", stdout);
+    assert!(stdout.contains("0.0%"), "{}", stdout);
+    assert!(stdout.contains("+50.0%"), "{}", stdout);
     let markdown = std::fs::read_to_string(export_path).unwrap();
-    insta::assert_snapshot!(markdown, @r"
-    | Command | Mean [s] | Min [s] | Max [s] | Relative |
+    insta::assert_snapshot!(markdown, @"
+    | Command | Mean Time [s] | Min [s] | Max [s] | Change |
     |:---|---:|---:|---:|---:|
-    | `baseline` | 2.000 | 2.000 | 2.000 | 1.00 (reference) |
-    | `sleep 1` | 1.000 | 1.000 | 1.000 | 2.00 (faster) |
-    | `sleep 2` | 2.000 | 2.000 | 2.000 | 1.00 (same speed) |
-    | `sleep 3` | 3.000 | 3.000 | 3.000 | 1.50 (slower) |
+    | `baseline` | 2.000 | 2.000 | 2.000 | reference |
+    | `sleep 1` | 1.000 | 1.000 | 1.000 | -50.0% |
+    | `sleep 2` | 2.000 | 2.000 | 2.000 | 0.0% |
+    | `sleep 3` | 3.000 | 3.000 | 3.000 | +50.0% |
     ");
 
     // Equal zero times have no meaningful relative factor.
@@ -773,10 +811,8 @@ fn command_sorted_comparison_and_markup_identify_reference() {
             "--style=none",
             "--runs=1",
             "--export-markdown=-",
-            "--reference",
+            "--command-name=baseline",
             "sleep 0",
-            "--reference-name",
-            "baseline",
             "sleep 0",
         ])
         .output()
@@ -791,33 +827,33 @@ fn command_sorted_comparison_and_markup_identify_reference() {
 }
 
 #[test]
-fn shows_reference_name() {
+fn shows_name_of_first_command() {
     let _settings = snapshot_settings().bind_to_scope();
     assert_cmd_snapshot!(hyperfine_debug()
+        .arg("--metrics=time_wall_clock,memory_peak_resident")
         .arg("--style=basic")
-        .arg("--reference=sleep 2.0")
-        .arg("--reference-name=refabc123")
+        .arg("sleep 2.0")
+        .arg("--command-name=refabc123")
         .arg("sleep 1.0")
-        .arg("sleep 3.0"), @r"
+        .arg("sleep 3.0"), @"
     success: true
     exit_code: 0
     ----- stdout -----
-    Benchmark 1: refabc123
-      Time (mean ± σ):      2.000 s ±  0.000 s    [User: 0.000 s, System: 0.000 s]
-      Range (min … max):    2.000 s …  2.000 s    10 runs
+    Benchmark 1: refabc123 (10 runs)
+                 mean     ±       σ          min     …     max
+      Time      2.000 s   ±   0.000 s      2.000 s   …   2.000 s
+      Memory      0.0 B   ±     0.0 B        0.0 B   …     0.0 B
 
-    Benchmark 2: sleep 1.0
-      Time (mean ± σ):      1.000 s ±  0.000 s    [User: 0.000 s, System: 0.000 s]
-      Range (min … max):    1.000 s …  1.000 s    10 runs
+    Benchmark 2: sleep 1.0 (10 runs)
+                 mean     ±       σ          min     …     max
+      Time      1.000 s   ±   0.000 s      1.000 s   …   1.000 s          -50.0%
+      Memory      0.0 B   ±     0.0 B        0.0 B   …     0.0 B             N/A
 
-    Benchmark 3: sleep 3.0
-      Time (mean ± σ):      3.000 s ±  0.000 s    [User: 0.000 s, System: 0.000 s]
-      Range (min … max):    3.000 s …  3.000 s    10 runs
+    Benchmark 3: sleep 3.0 (10 runs)
+                 mean     ±       σ          min     …     max
+      Time      3.000 s   ±   0.000 s      3.000 s   …   3.000 s          +50.0%
+      Memory      0.0 B   ±     0.0 B        0.0 B   …     0.0 B             N/A
 
-    Summary
-      refabc123 ran
-        2.00 ± 0.00 times slower than sleep 1.0
-        1.50 ± 0.00 times faster than sleep 3.0
 
     ----- stderr -----
     ");
@@ -827,6 +863,7 @@ fn shows_reference_name() {
 fn performs_all_benchmarks_in_parameter_scan() {
     let _settings = snapshot_settings().bind_to_scope();
     assert_cmd_snapshot!(hyperfine_debug()
+        .arg("--metrics=time_wall_clock,memory_peak_resident")
         .arg("--style=basic")
         .arg("--parameter-scan")
         .arg("time")
@@ -834,31 +871,30 @@ fn performs_all_benchmarks_in_parameter_scan() {
         .arg("45")
         .arg("--parameter-step-size")
         .arg("5")
-        .arg("sleep {time}"), @r"
+        .arg("sleep {time}"), @"
     success: true
     exit_code: 0
     ----- stdout -----
-    Benchmark 1: sleep 30
-      Time (mean ± σ):     30.000 s ±  0.000 s    [User: 0.000 s, System: 0.000 s]
-      Range (min … max):   30.000 s … 30.000 s    10 runs
+    Benchmark 1: sleep 30 (10 runs)
+                 mean     ±       σ          min     …     max
+      Time     30.000 s   ±   0.000 s     30.000 s   …  30.000 s
+      Memory      0.0 B   ±     0.0 B        0.0 B   …     0.0 B
 
-    Benchmark 2: sleep 35
-      Time (mean ± σ):     35.000 s ±  0.000 s    [User: 0.000 s, System: 0.000 s]
-      Range (min … max):   35.000 s … 35.000 s    10 runs
+    Benchmark 2: sleep 35 (10 runs)
+                 mean     ±       σ          min     …     max
+      Time     35.000 s   ±   0.000 s     35.000 s   …  35.000 s          +16.7%
+      Memory      0.0 B   ±     0.0 B        0.0 B   …     0.0 B             N/A
 
-    Benchmark 3: sleep 40
-      Time (mean ± σ):     40.000 s ±  0.000 s    [User: 0.000 s, System: 0.000 s]
-      Range (min … max):   40.000 s … 40.000 s    10 runs
+    Benchmark 3: sleep 40 (10 runs)
+                 mean     ±       σ          min     …     max
+      Time     40.000 s   ±   0.000 s     40.000 s   …  40.000 s          +33.3%
+      Memory      0.0 B   ±     0.0 B        0.0 B   …     0.0 B             N/A
 
-    Benchmark 4: sleep 45
-      Time (mean ± σ):     45.000 s ±  0.000 s    [User: 0.000 s, System: 0.000 s]
-      Range (min … max):   45.000 s … 45.000 s    10 runs
+    Benchmark 4: sleep 45 (10 runs)
+                 mean     ±       σ          min     …     max
+      Time     45.000 s   ±   0.000 s     45.000 s   …  45.000 s          +50.0%
+      Memory      0.0 B   ±     0.0 B        0.0 B   …     0.0 B             N/A
 
-    Summary
-      sleep 30 ran
-        1.17 ± 0.00 times faster than sleep 35
-        1.33 ± 0.00 times faster than sleep 40
-        1.50 ± 0.00 times faster than sleep 45
 
     ----- stderr -----
     ");
@@ -882,7 +918,7 @@ fn rejects_negative_parameter_steps() {
 
 #[cfg(unix)]
 #[test]
-fn selects_reference_with_parameterized_prepare() {
+fn preserves_input_order_with_parameterized_prepare() {
     let directory = tempfile::tempdir().unwrap();
     let csv_path = directory.path().join("results.csv");
     let json_path = directory.path().join("results.json");
@@ -896,8 +932,6 @@ fn selects_reference_with_parameterized_prepare() {
             "0.2,0.4,0.6",
             "--prepare",
             "sleep {delay}",
-            "--reference",
-            "echo a (delay = 0.4)",
             "--export-csv",
         ])
         .arg(&csv_path)
@@ -912,7 +946,7 @@ fn selects_reference_with_parameterized_prepare() {
     for (number, delay) in ["0.2", "0.4", "0.6"].iter().enumerate() {
         assert!(
             stdout.contains(&format!(
-                "Benchmark {}: echo a (delay = {})",
+                "Benchmark {}: echo a (delay = {}) (1 run)",
                 number + 1,
                 delay
             )),
@@ -920,7 +954,16 @@ fn selects_reference_with_parameterized_prepare() {
             stdout
         );
     }
-    assert!(stdout.contains("echo a (delay = 0.4) ran"), "{}", stdout);
+    assert!(
+        !stdout
+            .split("Benchmark 2")
+            .next()
+            .unwrap()
+            .contains("Change"),
+        "{}",
+        stdout
+    );
+    assert!(!stdout.contains("Change vs #1"));
 
     let mut csv = csv::Reader::from_path(csv_path).unwrap();
     assert!(csv
@@ -946,14 +989,21 @@ fn selects_reference_with_parameterized_prepare() {
 }
 
 #[test]
-fn rejects_unmatched_reference_before_export_or_setup() {
+fn rejects_invalid_metric_before_export_or_setup() {
     let directory = tempfile::tempdir().unwrap();
     let export_path = directory.path().join("results.csv");
     let marker_path = directory.path().join("setup-ran");
     std::fs::write(&export_path, "previous contents").unwrap();
 
     hyperfine()
-        .args(["--reference", "sleep 1", "-P", "secs", "2", "3", "--setup"])
+        .args([
+            "--metrics=memory_peak_resident:ms",
+            "-P",
+            "secs",
+            "2",
+            "3",
+            "--setup",
+        ])
         .arg(format!("echo touched > \"{}\"", marker_path.display()))
         .arg("--export-csv")
         .arg(&export_path)
@@ -962,7 +1012,7 @@ fn rejects_unmatched_reference_before_export_or_setup() {
         .failure()
         .stdout(predicate::str::is_empty())
         .stderr(predicate::str::contains(
-            "does not match any parameterized benchmark",
+            "Unit 'ms' is not valid for metric 'memory_peak_resident'",
         ));
     assert_eq!(
         std::fs::read_to_string(export_path).unwrap(),
@@ -971,29 +1021,9 @@ fn rejects_unmatched_reference_before_export_or_setup() {
     assert!(!marker_path.exists());
 }
 
-#[test]
-fn rejects_ambiguous_parameterized_reference() {
-    hyperfine_debug()
-        .args([
-            "-L",
-            "x",
-            "1,2",
-            "--command-name",
-            "case",
-            "--reference",
-            "case",
-            "sleep {x}",
-        ])
-        .assert()
-        .failure()
-        .stderr(predicate::str::contains(
-            "matches multiple parameterized benchmarks",
-        ));
-}
-
 #[cfg(unix)]
 #[test]
-fn intermediate_markdown_waits_for_selected_reference() {
+fn intermediate_markdown_retains_completed_reference() {
     let directory = tempfile::tempdir().unwrap();
     let export_path = directory.path().join("results.md");
     hyperfine()
@@ -1004,8 +1034,6 @@ fn intermediate_markdown_waits_for_selected_reference() {
             "-L",
             "delay",
             "0.01,0.02,0.03",
-            "--reference",
-            "sleep 0.02",
             "--prepare",
             "true",
             "--prepare",
@@ -1023,11 +1051,11 @@ fn intermediate_markdown_waits_for_selected_reference() {
         .lines()
         .find(|line| line.contains("sleep 0.01"))
         .unwrap();
-    assert!(row.ends_with("| N/A |"), "{}", row);
+    assert!(row.contains("reference"), "{}", row);
 }
 
 #[test]
-fn markdown_export_uses_selected_parameterized_reference() {
+fn markdown_export_uses_first_parameterized_benchmark_as_reference() {
     let _settings = snapshot_settings().bind_to_scope();
     assert_cmd_snapshot!(hyperfine_debug()
         .args([
@@ -1040,19 +1068,17 @@ fn markdown_export_uses_selected_parameterized_reference() {
             "3",
             "--command-name",
             "case-{x}",
-            "--reference",
-            "case-2",
             "sleep {x}",
-        ]), @r"
+        ]), @"
     success: true
     exit_code: 0
     ----- stdout -----
 
-    | Command | Mean [s] | Min [s] | Max [s] | Relative |
+    | Command | Mean Time [s] | Min [s] | Max [s] | Change |
     |:---|---:|---:|---:|---:|
-    | `case-1` | 1.000 | 1.000 | 1.000 | 2.00 (faster) |
-    | `case-2` | 2.000 | 2.000 | 2.000 | 1.00 (reference) |
-    | `case-3` | 3.000 | 3.000 | 3.000 | 1.50 (slower) |
+    | `case-1` | 1.000 | 1.000 | 1.000 | reference |
+    | `case-2` | 2.000 | 2.000 | 2.000 | +100.0% |
+    | `case-3` | 3.000 | 3.000 | 3.000 | +200.0% |
 
 
     ----- stderr -----
@@ -1067,15 +1093,15 @@ fn intermediate_results_are_not_exported_to_stdout() {
         .arg("--export-markdown")
         .arg("-")
         .arg("sleep 1")
-        .arg("sleep 2"), @r"
+        .arg("sleep 2"), @"
     success: true
     exit_code: 0
     ----- stdout -----
 
-    | Command | Mean [s] | Min [s] | Max [s] | Relative |
+    | Command | Mean Time [s] | Min [s] | Max [s] | Change |
     |:---|---:|---:|---:|---:|
-    | `sleep 1` | 1.000 ± 0.000 | 1.000 | 1.000 | 1.00 |
-    | `sleep 2` | 2.000 ± 0.000 | 2.000 | 2.000 | 2.00 ± 0.00 |
+    | `sleep 1` | 1.000 ± 0.000 | 1.000 | 1.000 | reference |
+    | `sleep 2` | 2.000 ± 0.000 | 2.000 | 2.000 | +100.0% |
 
 
     ----- stderr -----
@@ -1158,9 +1184,9 @@ fn markdown_export_preserves_backticks_and_pipes_in_command_names() {
     exit_code: 0
     ----- stdout -----
 
-    | Command | Mean [s] | Min [s] | Max [s] | Relative |
+    | Command | Mean Time [s] | Min [s] | Max [s] | Change |
     |:---|---:|---:|---:|---:|
-    | `` echo `uname` \| cat `` | 1.000 ± 0.000 | 1.000 | 1.000 | 1.00 |
+    | `` echo `uname` \| cat `` | 1.000 ± 0.000 | 1.000 | 1.000 | reference |
 
 
     ----- stderr -----
@@ -1183,60 +1209,6 @@ fn unused_parameters_are_shown_in_benchmark_name() {
         );
 }
 
-#[test]
-fn speed_comparison_sort_order() {
-    let _settings = snapshot_settings().bind_to_scope();
-    insta::allow_duplicates! {
-        for sort_order in ["auto", "mean-time"] {
-            assert_cmd_snapshot!(hyperfine_debug()
-                .arg("--style=basic")
-                .arg("sleep 2")
-                .arg("sleep 1")
-                .arg(format!("--sort={sort_order}")), @r"
-            success: true
-            exit_code: 0
-            ----- stdout -----
-            Benchmark 1: sleep 2
-              Time (mean ± σ):      2.000 s ±  0.000 s    [User: 0.000 s, System: 0.000 s]
-              Range (min … max):    2.000 s …  2.000 s    10 runs
-
-            Benchmark 2: sleep 1
-              Time (mean ± σ):      1.000 s ±  0.000 s    [User: 0.000 s, System: 0.000 s]
-              Range (min … max):    1.000 s …  1.000 s    10 runs
-
-            Summary
-              sleep 1 ran
-                2.00 ± 0.00 times faster than sleep 2
-
-            ----- stderr -----
-            ");
-        }
-    }
-
-    assert_cmd_snapshot!(hyperfine_debug()
-        .arg("--style=basic")
-        .arg("sleep 2")
-        .arg("sleep 1")
-        .arg("--sort=command"), @r"
-    success: true
-    exit_code: 0
-    ----- stdout -----
-    Benchmark 1: sleep 2
-      Time (mean ± σ):      2.000 s ±  0.000 s    [User: 0.000 s, System: 0.000 s]
-      Range (min … max):    2.000 s …  2.000 s    10 runs
-
-    Benchmark 2: sleep 1
-      Time (mean ± σ):      1.000 s ±  0.000 s    [User: 0.000 s, System: 0.000 s]
-      Range (min … max):    1.000 s …  1.000 s    10 runs
-
-    Relative speed comparison
-            2.00 ±  0.00  sleep 2
-            1.00          sleep 1
-
-    ----- stderr -----
-    ");
-}
-
 #[cfg(windows)]
 #[test]
 fn windows_quote_args() {
@@ -1308,8 +1280,8 @@ fn json_export_basic() {
         "--export-json=-",
         "--runs=2",
         "--warmup=1",
-        "--reference-name=one second",
-        "--reference=sleep 1",
+        "--command-name=one second",
+        "sleep 1",
         "--command-name=sleep 2",
         "sleep 2",
     ]));
@@ -1338,7 +1310,6 @@ fn json_export_parameterized_with_reference() {
         "duration",
         "1,2",
         "--command-name=sleep for {duration} seconds",
-        "--reference=sleep for 2 seconds",
         "sleep {duration}",
     ]));
 }