fix!: Remove unstable --shuffle and --shuffle-seed

Author: epage

crates/libtest-json/event.schema.json

@@ -44,14 +44,6 @@
         "elapsed_s": {
           "$ref": "#/$defs/Elapsed"
         },
-        "seed": {
-          "type": [
-            "integer",
-            "null"
-          ],
-          "format": "uint64",
-          "minimum": 0
-        },
         "event": {
           "type": "string",
           "const": "discover-complete"

crates/libtest-json/src/event.rs

@@ -13,7 +13,6 @@ pub enum Event {
     DiscoverComplete {
         #[allow(dead_code)]
         elapsed_s: Elapsed,
-        seed: Option<u64>,
     },
     SuiteStart,
     CaseStart {

crates/libtest-lexarg/src/lib.rs

@@ -30,8 +30,6 @@ pub struct TestOpts {
     pub nocapture: bool,
     pub color: ColorConfig,
     pub format: OutputFormat,
-    pub shuffle: bool,
-    pub shuffle_seed: Option<u64>,
     pub test_threads: Option<std::num::NonZeroUsize>,
     pub skip: Vec<String>,
     /// Stop at first failing test.
@@ -156,10 +154,6 @@ Options:
                         `VARIABLE=WARN_TIME,CRITICAL_TIME`.
                         `CRITICAL_TIME` here means the limit that should not
                         be exceeded by test.
-        --shuffle       Run tests in random order
-        --shuffle-seed SEED
-                        Run tests in random order; seed the random number
-                        generator with SEED
 "#;
 
 pub const AFTER_HELP: &str = r#"
@@ -171,12 +165,6 @@ By default, all tests are run in parallel. This can be altered with the
 --test-threads flag or the RUST_TEST_THREADS environment variable when running
 tests (set it to 1).
 
-By default, the tests are run in alphabetical order. Use --shuffle or set
-RUST_TEST_SHUFFLE to run the tests in random order. Pass the generated
-"shuffle seed" to --shuffle-seed (or set RUST_TEST_SHUFFLE_SEED) to run the
-tests in the same order again. Note that --shuffle and --shuffle-seed do not
-affect whether the tests are run in parallel.
-
 All tests have their standard output and standard error captured by default.
 This can be overridden with the --nocapture flag or setting RUST_TEST_NOCAPTURE
 environment variable to a value other than "0". Logging is not captured by default.
@@ -305,17 +293,6 @@ impl TestOptsBuilder {
                 // Don't validate `feature` as other parsers might provide values
                 self.opts.allowed_unstable.push(feature.to_owned());
             }
-            Long("shuffle") => {
-                self.opts.shuffle = true;
-            }
-            Long("shuffle-seed") => {
-                let seed = parser
-                    .next_flag_value()
-                    .ok_or_missing(Value(std::ffi::OsStr::new("SEED")))
-                    .parse()
-                    .within(arg)?;
-                self.opts.shuffle_seed = Some(seed);
-            }
             Value(filter) => {
                 let filter = filter.string("FILTER")?;
                 self.opts.filters.push(filter.to_owned());
@@ -335,37 +312,6 @@ impl TestOptsBuilder {
             .iter()
             .any(|f| f == UNSTABLE_OPTIONS);
 
-        if self.opts.shuffle && !allow_unstable_options {
-            return Err(ErrorContext::msg(
-                "`--shuffle` requires `-Zunstable-options`",
-            ));
-        }
-        if !self.opts.shuffle && allow_unstable_options {
-            self.opts.shuffle = match std::env::var("RUST_TEST_SHUFFLE") {
-                Ok(val) => &val != "0",
-                Err(_) => false,
-            };
-        }
-
-        if self.opts.shuffle_seed.is_some() && !allow_unstable_options {
-            return Err(ErrorContext::msg(
-                "`--shuffle-seed` requires `-Zunstable-options`",
-            ));
-        }
-        if self.opts.shuffle_seed.is_none() && allow_unstable_options {
-            self.opts.shuffle_seed = match std::env::var("RUST_TEST_SHUFFLE_SEED") {
-                Ok(val) => match val.parse::<u64>() {
-                    Ok(n) => Some(n),
-                    Err(_) => {
-                        return Err(ErrorContext::msg(
-                            "RUST_TEST_SHUFFLE_SEED is `{val}`, should be a number.",
-                        ));
-                    }
-                },
-                Err(_) => None,
-            };
-        }
-
         if !self.opts.nocapture {
             self.opts.nocapture = match std::env::var("RUST_TEST_NOCAPTURE") {
                 Ok(val) => &val != "0",

crates/libtest2-harness/src/harness.rs

@@ -1,6 +1,6 @@
 use libtest_lexarg::OutputFormat;
 
-use crate::{cli, notify, shuffle, Case, RunError, RunMode, State};
+use crate::{cli, notify, Case, RunError, RunMode, State};
 
 pub struct Harness {
     raw: Vec<std::ffi::OsString>,
@@ -172,10 +172,6 @@ fn discover(
 
     // Do this first so it applies to both discover and running
     cases.sort_unstable_by_key(|case| case.name().to_owned());
-    let seed = shuffle::get_shuffle_seed(opts);
-    if let Some(seed) = seed {
-        shuffle::shuffle_tests(seed, cases);
-    }
 
     let matches_filter = |case: &dyn Case, filter: &str| {
         let test_name = case.name();
@@ -207,7 +203,6 @@ fn discover(
 
     notifier.notify(notify::Event::DiscoverComplete {
         elapsed_s: notify::Elapsed(timer.elapsed()),
-        seed,
     })?;
 
     Ok(())

crates/libtest2-harness/src/lib.rs

@@ -28,7 +28,6 @@
 mod case;
 mod harness;
 mod notify;
-mod shuffle;
 mod state;
 
 pub mod cli;

crates/libtest2-harness/src/notify/summary.rs

@@ -5,7 +5,6 @@ use super::OK;
 
 #[derive(Default, Clone, Debug)]
 pub(crate) struct Summary {
-    pub(crate) seed: Option<u64>,
     pub(crate) failures: std::collections::BTreeMap<String, Option<String>>,
     pub(crate) elapsed_s: super::Elapsed,
 
@@ -29,13 +28,9 @@ impl Summary {
 
     pub(crate) fn write_start(&self, writer: &mut dyn std::io::Write) -> std::io::Result<()> {
         let s = if self.num_run == 1 { "" } else { "s" };
-        let seed = self
-            .seed
-            .map(|s| format!(" (shuffle seed: {s})"))
-            .unwrap_or_default();
 
         writeln!(writer)?;
-        writeln!(writer, "running {} test{s}{seed}", self.num_run)?;
+        writeln!(writer, "running {} test{s}", self.num_run)?;
         Ok(())
     }
 
@@ -95,9 +90,7 @@ impl super::Notifier for Summary {
                     self.num_filtered_out += 1;
                 }
             }
-            Event::DiscoverComplete { seed, .. } => {
-                self.seed = seed;
-            }
+            Event::DiscoverComplete { .. } => {}
             Event::SuiteStart => {}
             Event::CaseStart { .. } => {}
             Event::CaseComplete {

crates/libtest2-harness/src/shuffle.rs

@@ -629,7 +629,7 @@ fn list_json() {
 {"event":"discover-case","name":"fox","mode":"test","run":false}
 {"event":"discover-case","name":"frog","mode":"test","run":false}
 {"event":"discover-case","name":"owl","mode":"test","run":false}
-{"event":"discover-complete","elapsed_s":"[..]","seed":null}
+{"event":"discover-complete","elapsed_s":"[..]"}
 "#,
         r#"{"event":"discover-start"}
 {"event":"discover-case","name":"bear","mode":"test","run":true}
@@ -640,7 +640,7 @@ fn list_json() {
 {"event":"discover-case","name":"fox","mode":"test","run":false}
 {"event":"discover-case","name":"frog","mode":"test","run":false}
 {"event":"discover-case","name":"owl","mode":"test","run":false}
-{"event":"discover-complete","elapsed_s":"[..]","seed":null}
+{"event":"discover-complete","elapsed_s":"[..]"}
 "#,
     );
 }
@@ -660,7 +660,7 @@ fn test_json() {
 {"event":"discover-case","name":"fox","mode":"test","run":false}
 {"event":"discover-case","name":"frog","mode":"test","run":false}
 {"event":"discover-case","name":"owl","mode":"test","run":false}
-{"event":"discover-complete","elapsed_s":"[..]","seed":null}
+{"event":"discover-complete","elapsed_s":"[..]"}
 {"event":"suite-start"}
 {"event":"case-start","name":"bear"}
 {"event":"case-complete","name":"bear","mode":"test","status":"ignored","message":"fails","elapsed_s":"[..]"}
@@ -677,7 +677,7 @@ fn test_json() {
 {"event":"discover-case","name":"fox","mode":"test","run":false}
 {"event":"discover-case","name":"frog","mode":"test","run":false}
 {"event":"discover-case","name":"owl","mode":"test","run":false}
-{"event":"discover-complete","elapsed_s":"[..]","seed":null}
+{"event":"discover-complete","elapsed_s":"[..]"}
 {"event":"suite-start"}
 [..]
 [..]
@@ -773,63 +773,3 @@ test result: FAILED. 2 passed; 1 failed; 5 ignored; 0 filtered out; finished in
 "#,
     );
 }
-
-#[test]
-fn shuffle() {
-    check(
-        &["-Zunstable-options", "--list", "--shuffle-seed=1"],
-        0,
-        r#"fox: test
-cat: test
-fly: test
-bear: test
-owl: test
-frog: test
-bunny: test
-dog: test
-
-8 tests
-
-"#,
-        r#"fox: test
-cat: test
-fly: test
-bear: test
-owl: test
-frog: test
-bunny: test
-dog: test
-
-8 tests
-
-"#,
-    );
-    check(
-        &["-Zunstable-options", "--list", "--shuffle-seed=2"],
-        0,
-        r#"owl: test
-dog: test
-fox: test
-frog: test
-bear: test
-fly: test
-bunny: test
-cat: test
-
-8 tests
-
-"#,
-        r#"owl: test
-dog: test
-fox: test
-frog: test
-bear: test
-fly: test
-bunny: test
-cat: test
-
-8 tests
-
-"#,
-    );
-}