From b0397998cf282ea40ce340eb8bb90499a6ad71df Mon Sep 17 00:00:00 2001
From: Ed Page <eopage@gmail.com>
Date: Thu, 10 Jul 2025 16:43:42 -0500
Subject: [PATCH 1/3] test: Switch to snapshot testing

---
 Cargo.lock                                    |   2 +
 crates/libtest2-mimic/Cargo.toml              |   2 +-
 .../tests/testsuite/all_passing.rs            | 113 ++--
 .../tests/testsuite/main_thread.rs            |  11 +-
 .../tests/testsuite/mixed_bag.rs              | 536 ++++++++++++++----
 .../libtest2-mimic/tests/testsuite/panic.rs   |  17 +-
 crates/libtest2/Cargo.toml                    |   2 +-
 .../libtest2/tests/testsuite/all_passing.rs   | 113 ++--
 crates/libtest2/tests/testsuite/mixed_bag.rs  | 536 ++++++++++++++----
 crates/libtest2/tests/testsuite/panic.rs      |  17 +-
 10 files changed, 1033 insertions(+), 316 deletions(-)

diff --git a/Cargo.lock b/Cargo.lock
index bb307ce..2f55a02 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -363,6 +363,8 @@ dependencies = [
  "anstream",
  "anstyle",
  "normalize-line-endings",
+ "serde",
+ "serde_json",
  "similar",
  "snapbox-macros",
 ]
diff --git a/crates/libtest2-mimic/Cargo.toml b/crates/libtest2-mimic/Cargo.toml
index 6e03675..a9abd2b 100644
--- a/crates/libtest2-mimic/Cargo.toml
+++ b/crates/libtest2-mimic/Cargo.toml
@@ -37,7 +37,7 @@ dunce = "1.0.4"
 escargot = "0.5.8"
 once_cell_polyfill = "1.56.0"
 pathdiff = "0.2.1"
-snapbox = "0.6.0"
+snapbox = { version = "0.6.0", features = ["json"] }
 
 [lints]
 workspace = true
diff --git a/crates/libtest2-mimic/tests/testsuite/all_passing.rs b/crates/libtest2-mimic/tests/testsuite/all_passing.rs
index 4a9f681..6438fe5 100644
--- a/crates/libtest2-mimic/tests/testsuite/all_passing.rs
+++ b/crates/libtest2-mimic/tests/testsuite/all_passing.rs
@@ -1,3 +1,6 @@
+use snapbox::prelude::*;
+use snapbox::str;
+
 fn test_cmd() -> snapbox::cmd::Command {
     static BIN: once_cell_polyfill::sync::OnceLock<(std::path::PathBuf, std::path::PathBuf)> =
         once_cell_polyfill::sync::OnceLock::new();
@@ -23,7 +26,7 @@ fn main() {
     snapbox::cmd::Command::new(bin).current_dir(current_dir)
 }
 
-fn check(args: &[&str], single: &str, parallel: &str) {
+fn check(args: &[&str], single: impl IntoData, parallel: impl IntoData) {
     test_cmd()
         .args(args)
         .args(["--test-threads", "1"])
@@ -37,7 +40,8 @@ fn check(args: &[&str], single: &str, parallel: &str) {
 fn normal() {
     check(
         &[],
-        r#"
+        str![[r#"
+
 running 3 tests
 test bar   ... ok
 test barro ... ok
@@ -45,14 +49,17 @@ test foo   ... ok
 
 test result: ok. 3 passed; 0 failed; 0 ignored; 0 filtered out; finished in [..]s
 
-"#,
-        r#"
+
+"#]],
+        str![[r#"
+
 running 3 tests
 ...
 
 test result: ok. 3 passed; 0 failed; 0 ignored; 0 filtered out; finished in [..]s
 
-"#,
+
+"#]],
     );
 }
 
@@ -60,20 +67,24 @@ test result: ok. 3 passed; 0 failed; 0 ignored; 0 filtered out; finished in [..]
 fn filter_one() {
     check(
         &["foo"],
-        r#"
+        str![[r#"
+
 running 1 test
 test foo ... ok
 
 test result: ok. 1 passed; 0 failed; 0 ignored; 2 filtered out; finished in [..]s
 
-"#,
-        r#"
+
+"#]],
+        str![[r#"
+
 running 1 test
 test foo ... ok
 
 test result: ok. 1 passed; 0 failed; 0 ignored; 2 filtered out; finished in [..]s
 
-"#,
+
+"#]],
     );
 }
 
@@ -81,21 +92,25 @@ test result: ok. 1 passed; 0 failed; 0 ignored; 2 filtered out; finished in [..]
 fn filter_two() {
     check(
         &["bar"],
-        r#"
+        str![[r#"
+
 running 2 tests
 test bar   ... ok
 test barro ... ok
 
 test result: ok. 2 passed; 0 failed; 0 ignored; 1 filtered out; finished in [..]s
 
-"#,
-        r#"
+
+"#]],
+        str![[r#"
+
 running 2 tests
 ...
 
 test result: ok. 2 passed; 0 failed; 0 ignored; 1 filtered out; finished in [..]s
 
-"#,
+
+"#]],
     );
 }
 
@@ -103,20 +118,24 @@ test result: ok. 2 passed; 0 failed; 0 ignored; 1 filtered out; finished in [..]
 fn filter_exact() {
     check(
         &["bar", "--exact"],
-        r#"
+        str![[r#"
+
 running 1 test
 test bar ... ok
 
 test result: ok. 1 passed; 0 failed; 0 ignored; 2 filtered out; finished in [..]s
 
-"#,
-        r#"
+
+"#]],
+        str![[r#"
+
 running 1 test
 test bar ... ok
 
 test result: ok. 1 passed; 0 failed; 0 ignored; 2 filtered out; finished in [..]s
 
-"#,
+
+"#]],
     );
 }
 
@@ -124,20 +143,24 @@ test result: ok. 1 passed; 0 failed; 0 ignored; 2 filtered out; finished in [..]
 fn filter_two_and_skip() {
     check(
         &["--skip", "barro", "bar"],
-        r#"
+        str![[r#"
+
 running 1 test
 test bar ... ok
 
 test result: ok. 1 passed; 0 failed; 0 ignored; 2 filtered out; finished in [..]s
 
-"#,
-        r#"
+
+"#]],
+        str![[r#"
+
 running 1 test
 test bar ... ok
 
 test result: ok. 1 passed; 0 failed; 0 ignored; 2 filtered out; finished in [..]s
 
-"#,
+
+"#]],
     );
 }
 
@@ -145,7 +168,8 @@ test result: ok. 1 passed; 0 failed; 0 ignored; 2 filtered out; finished in [..]
 fn skip_nothing() {
     check(
         &["--skip", "peter"],
-        r#"
+        str![[r#"
+
 running 3 tests
 test bar   ... ok
 test barro ... ok
@@ -153,14 +177,17 @@ test foo   ... ok
 
 test result: ok. 3 passed; 0 failed; 0 ignored; 0 filtered out; finished in [..]s
 
-"#,
-        r#"
+
+"#]],
+        str![[r#"
+
 running 3 tests
 ...
 
 test result: ok. 3 passed; 0 failed; 0 ignored; 0 filtered out; finished in [..]s
 
-"#,
+
+"#]],
     );
 }
 
@@ -168,20 +195,24 @@ test result: ok. 3 passed; 0 failed; 0 ignored; 0 filtered out; finished in [..]
 fn skip_two() {
     check(
         &["--skip", "bar"],
-        r#"
+        str![[r#"
+
 running 1 test
 test foo ... ok
 
 test result: ok. 1 passed; 0 failed; 0 ignored; 2 filtered out; finished in [..]s
 
-"#,
-        r#"
+
+"#]],
+        str![[r#"
+
 running 1 test
 test foo ... ok
 
 test result: ok. 1 passed; 0 failed; 0 ignored; 2 filtered out; finished in [..]s
 
-"#,
+
+"#]],
     );
 }
 
@@ -189,21 +220,25 @@ test result: ok. 1 passed; 0 failed; 0 ignored; 2 filtered out; finished in [..]
 fn skip_exact() {
     check(
         &["--exact", "--skip", "bar"],
-        r#"
+        str![[r#"
+
 running 2 tests
 test barro ... ok
 test foo   ... ok
 
 test result: ok. 2 passed; 0 failed; 0 ignored; 1 filtered out; finished in [..]s
 
-"#,
-        r#"
+
+"#]],
+        str![[r#"
+
 running 2 tests
 ...
 
 test result: ok. 2 passed; 0 failed; 0 ignored; 1 filtered out; finished in [..]s
 
-"#,
+
+"#]],
     );
 }
 
@@ -211,17 +246,21 @@ test result: ok. 2 passed; 0 failed; 0 ignored; 1 filtered out; finished in [..]
 fn terse_output() {
     check(
         &["--quiet", "--skip", "foo"],
-        r#"
+        str![[r#"
+
 running 2 tests
 ..
 test result: ok. 2 passed; 0 failed; 0 ignored; 1 filtered out; finished in [..]s
 
-"#,
-        r#"
+
+"#]],
+        str![[r#"
+
 running 2 tests
 ..
 test result: ok. 2 passed; 0 failed; 0 ignored; 1 filtered out; finished in [..]s
 
-"#,
+
+"#]],
     );
 }
diff --git a/crates/libtest2-mimic/tests/testsuite/main_thread.rs b/crates/libtest2-mimic/tests/testsuite/main_thread.rs
index f303e87..48cf9ed 100644
--- a/crates/libtest2-mimic/tests/testsuite/main_thread.rs
+++ b/crates/libtest2-mimic/tests/testsuite/main_thread.rs
@@ -1,3 +1,5 @@
+use snapbox::str;
+
 #[test]
 fn check_test_on_main_thread() {
     let package_root = crate::util::new_test(
@@ -22,9 +24,10 @@ fn main() {
         .current_dir(package_root)
         .assert()
         .success()
-        .stdout_eq(
-            "
+        .stdout_eq(str![[r#"
+
 running 1 test
-...",
-        );
+...
+
+"#]]);
 }
diff --git a/crates/libtest2-mimic/tests/testsuite/mixed_bag.rs b/crates/libtest2-mimic/tests/testsuite/mixed_bag.rs
index 9f90376..49c16d2 100644
--- a/crates/libtest2-mimic/tests/testsuite/mixed_bag.rs
+++ b/crates/libtest2-mimic/tests/testsuite/mixed_bag.rs
@@ -1,3 +1,6 @@
+use snapbox::prelude::*;
+use snapbox::str;
+
 fn test_cmd() -> snapbox::cmd::Command {
     static BIN: once_cell_polyfill::sync::OnceLock<(std::path::PathBuf, std::path::PathBuf)> =
         once_cell_polyfill::sync::OnceLock::new();
@@ -44,7 +47,7 @@ fn main() {
     snapbox::cmd::Command::new(bin).current_dir(current_dir)
 }
 
-fn check(args: &[&str], code: i32, single: &str, parallel: &str) {
+fn check(args: &[&str], code: i32, single: impl IntoData, parallel: impl IntoData) {
     test_cmd()
         .args(args)
         .args(["--test-threads", "1"])
@@ -63,7 +66,8 @@ fn normal() {
     check(
         &[],
         101,
-        r#"
+        str![[r#"
+
 running 8 tests
 test bear  ... ignored
 test bunny ... ignored
@@ -85,8 +89,10 @@ failures:
 
 test result: FAILED. 2 passed; 1 failed; 5 ignored; 0 filtered out; finished in [..]s
 
-"#,
-        r#"
+
+"#]],
+        str![[r#"
+
 running 8 tests
 ...
 
@@ -101,7 +107,8 @@ failures:
 
 test result: FAILED. 2 passed; 1 failed; 5 ignored; 0 filtered out; finished in [..]s
 
-"#,
+
+"#]],
     );
 }
 
@@ -110,7 +117,8 @@ fn test_mode() {
     check(
         &["--test"],
         101,
-        r#"
+        str![[r#"
+
 running 8 tests
 test bear  ... ignored
 test bunny ... ignored
@@ -132,8 +140,10 @@ failures:
 
 test result: FAILED. 2 passed; 1 failed; 5 ignored; 0 filtered out; finished in [..]s
 
-"#,
-        r#"
+
+"#]],
+        str![[r#"
+
 running 8 tests
 ...
 
@@ -148,7 +158,8 @@ failures:
 
 test result: FAILED. 2 passed; 1 failed; 5 ignored; 0 filtered out; finished in [..]s
 
-"#,
+
+"#]],
     );
 }
 
@@ -157,7 +168,8 @@ fn bench_mode() {
     check(
         &["--bench"],
         101,
-        r#"
+        str![[r#"
+
 running 8 tests
 test bear  ... ignored
 test bunny ... ignored
@@ -179,8 +191,10 @@ failures:
 
 test result: FAILED. 2 passed; 1 failed; 5 ignored; 0 filtered out; finished in [..]s
 
-"#,
-        r#"
+
+"#]],
+        str![[r#"
+
 running 8 tests
 ...
 
@@ -195,7 +209,8 @@ failures:
 
 test result: FAILED. 2 passed; 1 failed; 5 ignored; 0 filtered out; finished in [..]s
 
-"#,
+
+"#]],
     );
 }
 
@@ -204,7 +219,8 @@ fn list() {
     check(
         &["--list"],
         0,
-        r#"bear: test
+        str![[r#"
+bear: test
 bunny: test
 cat: test
 dog: test
@@ -215,8 +231,10 @@ owl: test
 
 8 tests
 
-"#,
-        r#"bear: test
+
+"#]],
+        str![[r#"
+bear: test
 bunny: test
 cat: test
 dog: test
@@ -227,7 +245,8 @@ owl: test
 
 8 tests
 
-"#,
+
+"#]],
     );
 }
 
@@ -236,7 +255,8 @@ fn list_ignored() {
     check(
         &["--list", "--ignored"],
         0,
-        r#"bear: test
+        str![[r#"
+bear: test
 bunny: test
 cat: test
 dog: test
@@ -247,8 +267,10 @@ owl: test
 
 8 tests
 
-"#,
-        r#"bear: test
+
+"#]],
+        str![[r#"
+bear: test
 bunny: test
 cat: test
 dog: test
@@ -259,7 +281,8 @@ owl: test
 
 8 tests
 
-"#,
+
+"#]],
     );
 }
 
@@ -268,18 +291,22 @@ fn list_with_filter() {
     check(
         &["--list", "a"],
         0,
-        r#"bear: test
+        str![[r#"
+bear: test
 cat: test
 
 2 tests
 
-"#,
-        r#"bear: test
+
+"#]],
+        str![[r#"
+bear: test
 cat: test
 
 2 tests
 
-"#,
+
+"#]],
     );
 }
 
@@ -288,21 +315,25 @@ fn filter_c() {
     check(
         &["a"],
         0,
-        r#"
+        str![[r#"
+
 running 2 tests
 test bear ... ignored
 test cat  ... ok
 
 test result: ok. 1 passed; 0 failed; 1 ignored; 6 filtered out; finished in [..]s
 
-"#,
-        r#"
+
+"#]],
+        str![[r#"
+
 running 2 tests
 ...
 
 test result: ok. 1 passed; 0 failed; 1 ignored; 6 filtered out; finished in [..]s
 
-"#,
+
+"#]],
     );
 }
 
@@ -311,21 +342,25 @@ fn filter_o_test() {
     check(
         &["--test", "a"],
         0,
-        r#"
+        str![[r#"
+
 running 2 tests
 test bear ... ignored
 test cat  ... ok
 
 test result: ok. 1 passed; 0 failed; 1 ignored; 6 filtered out; finished in [..]s
 
-"#,
-        r#"
+
+"#]],
+        str![[r#"
+
 running 2 tests
 ...
 
 test result: ok. 1 passed; 0 failed; 1 ignored; 6 filtered out; finished in [..]s
 
-"#,
+
+"#]],
     );
 }
 
@@ -334,7 +369,8 @@ fn filter_o_test_include_ignored() {
     check(
         &["--test", "--include-ignored", "o"],
         101,
-        r#"
+        str![[r#"
+
 running 4 tests
 test dog  ... FAILED
 test fox  ... ok
@@ -356,8 +392,10 @@ failures:
 
 test result: FAILED. 2 passed; 2 failed; 0 ignored; 4 filtered out; finished in [..]s
 
-"#,
-        r#"
+
+"#]],
+        str![[r#"
+
 running 4 tests
 ...
 
@@ -376,7 +414,8 @@ failures:
 
 test result: FAILED. 2 passed; 2 failed; 0 ignored; 4 filtered out; finished in [..]s
 
-"#,
+
+"#]],
     );
 }
 
@@ -385,7 +424,8 @@ fn filter_o_test_ignored() {
     check(
         &["--test", "--ignored", "o"],
         101,
-        r#"
+        str![[r#"
+
 running 4 tests
 test dog  ... FAILED
 test fox  ... ok
@@ -407,8 +447,10 @@ failures:
 
 test result: FAILED. 2 passed; 2 failed; 0 ignored; 4 filtered out; finished in [..]s
 
-"#,
-        r#"
+
+"#]],
+        str![[r#"
+
 running 4 tests
 ...
 
@@ -427,7 +469,8 @@ failures:
 
 test result: FAILED. 2 passed; 2 failed; 0 ignored; 4 filtered out; finished in [..]s
 
-"#,
+
+"#]],
     );
 }
 
@@ -436,7 +479,8 @@ fn normal_include_ignored() {
     check(
         &["--include-ignored"],
         101,
-        r#"
+        str![[r#"
+
 running 8 tests
 test bear  ... FAILED
 test bunny ... FAILED
@@ -470,8 +514,10 @@ failures:
 
 test result: FAILED. 4 passed; 4 failed; 0 ignored; 0 filtered out; finished in [..]s
 
-"#,
-        r#"
+
+"#]],
+        str![[r#"
+
 running 8 tests
 ...
 
@@ -498,7 +544,8 @@ failures:
 
 test result: FAILED. 4 passed; 4 failed; 0 ignored; 0 filtered out; finished in [..]s
 
-"#,
+
+"#]],
     );
 }
 
@@ -507,7 +554,8 @@ fn normal_ignored() {
     check(
         &["--ignored"],
         101,
-        r#"
+        str![[r#"
+
 running 8 tests
 test bear  ... FAILED
 test bunny ... FAILED
@@ -541,8 +589,10 @@ failures:
 
 test result: FAILED. 4 passed; 4 failed; 0 ignored; 0 filtered out; finished in [..]s
 
-"#,
-        r#"
+
+"#]],
+        str![[r#"
+
 running 8 tests
 ...
 
@@ -569,7 +619,8 @@ failures:
 
 test result: FAILED. 4 passed; 4 failed; 0 ignored; 0 filtered out; finished in [..]s
 
-"#,
+
+"#]],
     );
 }
 
@@ -578,7 +629,8 @@ fn lots_of_flags() {
     check(
         &["--ignored", "--skip", "g", "--test", "o"],
         101,
-        r#"
+        str![[r#"
+
 running 2 tests
 test fox ... ok
 test owl ... FAILED
@@ -594,8 +646,10 @@ failures:
 
 test result: FAILED. 1 passed; 1 failed; 0 ignored; 6 filtered out; finished in [..]s
 
-"#,
-        r#"
+
+"#]],
+        str![[r#"
+
 running 2 tests
 ...
 
@@ -610,7 +664,8 @@ failures:
 
 test result: FAILED. 1 passed; 1 failed; 0 ignored; 6 filtered out; finished in [..]s
 
-"#,
+
+"#]],
     );
 }
 
@@ -620,28 +675,128 @@ fn list_json() {
     check(
         &["-Zunstable-options", "--format=json", "--list", "a"],
         0,
-        r#"{"event":"discover-start"}
-{"event":"discover-case","name":"bear","mode":"test","run":true}
-{"event":"discover-case","name":"bunny","mode":"test","run":false}
-{"event":"discover-case","name":"cat","mode":"test","run":true}
-{"event":"discover-case","name":"dog","mode":"test","run":false}
-{"event":"discover-case","name":"fly","mode":"test","run":false}
-{"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":"[..]"}
-"#,
-        r#"{"event":"discover-start"}
-{"event":"discover-case","name":"bear","mode":"test","run":true}
-{"event":"discover-case","name":"bunny","mode":"test","run":false}
-{"event":"discover-case","name":"cat","mode":"test","run":true}
-{"event":"discover-case","name":"dog","mode":"test","run":false}
-{"event":"discover-case","name":"fly","mode":"test","run":false}
-{"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":"[..]"}
-"#,
+        str![[r#"
+[
+  {
+    "event": "discover-start"
+  },
+  {
+    "event": "discover-case",
+    "mode": "test",
+    "name": "bear",
+    "run": true
+  },
+  {
+    "event": "discover-case",
+    "mode": "test",
+    "name": "bunny",
+    "run": false
+  },
+  {
+    "event": "discover-case",
+    "mode": "test",
+    "name": "cat",
+    "run": true
+  },
+  {
+    "event": "discover-case",
+    "mode": "test",
+    "name": "dog",
+    "run": false
+  },
+  {
+    "event": "discover-case",
+    "mode": "test",
+    "name": "fly",
+    "run": false
+  },
+  {
+    "event": "discover-case",
+    "mode": "test",
+    "name": "fox",
+    "run": false
+  },
+  {
+    "event": "discover-case",
+    "mode": "test",
+    "name": "frog",
+    "run": false
+  },
+  {
+    "event": "discover-case",
+    "mode": "test",
+    "name": "owl",
+    "run": false
+  },
+  {
+    "elapsed_s": "[..]",
+    "event": "discover-complete"
+  }
+]
+"#]]
+        .is_json()
+        .against_jsonlines(),
+        str![[r#"
+[
+  {
+    "event": "discover-start"
+  },
+  {
+    "event": "discover-case",
+    "mode": "test",
+    "name": "bear",
+    "run": true
+  },
+  {
+    "event": "discover-case",
+    "mode": "test",
+    "name": "bunny",
+    "run": false
+  },
+  {
+    "event": "discover-case",
+    "mode": "test",
+    "name": "cat",
+    "run": true
+  },
+  {
+    "event": "discover-case",
+    "mode": "test",
+    "name": "dog",
+    "run": false
+  },
+  {
+    "event": "discover-case",
+    "mode": "test",
+    "name": "fly",
+    "run": false
+  },
+  {
+    "event": "discover-case",
+    "mode": "test",
+    "name": "fox",
+    "run": false
+  },
+  {
+    "event": "discover-case",
+    "mode": "test",
+    "name": "frog",
+    "run": false
+  },
+  {
+    "event": "discover-case",
+    "mode": "test",
+    "name": "owl",
+    "run": false
+  },
+  {
+    "elapsed_s": "[..]",
+    "event": "discover-complete"
+  }
+]
+"#]]
+        .is_json()
+        .against_jsonlines(),
     );
 }
 
@@ -651,40 +806,191 @@ fn test_json() {
     check(
         &["-Zunstable-options", "--format=json", "a"],
         0,
-        r#"{"event":"discover-start"}
-{"event":"discover-case","name":"bear","mode":"test","run":true}
-{"event":"discover-case","name":"bunny","mode":"test","run":false}
-{"event":"discover-case","name":"cat","mode":"test","run":true}
-{"event":"discover-case","name":"dog","mode":"test","run":false}
-{"event":"discover-case","name":"fly","mode":"test","run":false}
-{"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":"[..]"}
-{"event":"suite-start"}
-{"event":"case-start","name":"bear"}
-{"event":"case-complete","name":"bear","mode":"test","status":"ignored","message":"fails","elapsed_s":"[..]"}
-{"event":"case-start","name":"cat"}
-{"event":"case-complete","name":"cat","mode":"test","status":null,"message":null,"elapsed_s":"[..]"}
-{"event":"suite-complete","elapsed_s":"[..]"}
-"#,
-        r#"{"event":"discover-start"}
-{"event":"discover-case","name":"bear","mode":"test","run":true}
-{"event":"discover-case","name":"bunny","mode":"test","run":false}
-{"event":"discover-case","name":"cat","mode":"test","run":true}
-{"event":"discover-case","name":"dog","mode":"test","run":false}
-{"event":"discover-case","name":"fly","mode":"test","run":false}
-{"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":"[..]"}
-{"event":"suite-start"}
-[..]
-[..]
-[..]
-[..]
-{"event":"suite-complete","elapsed_s":"[..]"}
-"#,
+        str![[r#"
+[
+  {
+    "event": "discover-start"
+  },
+  {
+    "event": "discover-case",
+    "mode": "test",
+    "name": "bear",
+    "run": true
+  },
+  {
+    "event": "discover-case",
+    "mode": "test",
+    "name": "bunny",
+    "run": false
+  },
+  {
+    "event": "discover-case",
+    "mode": "test",
+    "name": "cat",
+    "run": true
+  },
+  {
+    "event": "discover-case",
+    "mode": "test",
+    "name": "dog",
+    "run": false
+  },
+  {
+    "event": "discover-case",
+    "mode": "test",
+    "name": "fly",
+    "run": false
+  },
+  {
+    "event": "discover-case",
+    "mode": "test",
+    "name": "fox",
+    "run": false
+  },
+  {
+    "event": "discover-case",
+    "mode": "test",
+    "name": "frog",
+    "run": false
+  },
+  {
+    "event": "discover-case",
+    "mode": "test",
+    "name": "owl",
+    "run": false
+  },
+  {
+    "elapsed_s": "[..]",
+    "event": "discover-complete"
+  },
+  {
+    "event": "suite-start"
+  },
+  {
+    "event": "case-start",
+    "name": "bear"
+  },
+  {
+    "elapsed_s": "[..]",
+    "event": "case-complete",
+    "message": "fails",
+    "mode": "test",
+    "name": "bear",
+    "status": "ignored"
+  },
+  {
+    "event": "case-start",
+    "name": "cat"
+  },
+  {
+    "elapsed_s": "[..]",
+    "event": "case-complete",
+    "message": null,
+    "mode": "test",
+    "name": "cat",
+    "status": null
+  },
+  {
+    "elapsed_s": "[..]",
+    "event": "suite-complete"
+  }
+]
+"#]]
+        .is_json()
+        .against_jsonlines(),
+        str![[r#"
+[
+  {
+    "event": "discover-start"
+  },
+  {
+    "event": "discover-case",
+    "mode": "test",
+    "name": "bear",
+    "run": true
+  },
+  {
+    "event": "discover-case",
+    "mode": "test",
+    "name": "bunny",
+    "run": false
+  },
+  {
+    "event": "discover-case",
+    "mode": "test",
+    "name": "cat",
+    "run": true
+  },
+  {
+    "event": "discover-case",
+    "mode": "test",
+    "name": "dog",
+    "run": false
+  },
+  {
+    "event": "discover-case",
+    "mode": "test",
+    "name": "fly",
+    "run": false
+  },
+  {
+    "event": "discover-case",
+    "mode": "test",
+    "name": "fox",
+    "run": false
+  },
+  {
+    "event": "discover-case",
+    "mode": "test",
+    "name": "frog",
+    "run": false
+  },
+  {
+    "event": "discover-case",
+    "mode": "test",
+    "name": "owl",
+    "run": false
+  },
+  {
+    "elapsed_s": "[..]",
+    "event": "discover-complete"
+  },
+  {
+    "event": "suite-start"
+  },
+  {
+    "event": "case-start",
+    "name": "bear"
+  },
+  {
+    "elapsed_s": "[..]",
+    "event": "case-complete",
+    "message": "fails",
+    "mode": "test",
+    "name": "bear",
+    "status": "ignored"
+  },
+  {
+    "event": "case-start",
+    "name": "cat"
+  },
+  {
+    "elapsed_s": "[..]",
+    "event": "case-complete",
+    "message": null,
+    "mode": "test",
+    "name": "cat",
+    "status": null
+  },
+  {
+    "elapsed_s": "[..]",
+    "event": "suite-complete"
+  }
+]
+"#]]
+        .unordered()
+        .is_json()
+        .against_jsonlines(),
     );
 }
 
@@ -693,7 +999,8 @@ fn terse_output() {
     check(
         &["--quiet"],
         101,
-        r#"
+        str![[r#"
+
 running 8 tests
 ii.Fi.ii
 failures:
@@ -707,8 +1014,10 @@ failures:
 
 test result: FAILED. 2 passed; 1 failed; 5 ignored; 0 filtered out; finished in [..]s
 
-"#,
-        r#"
+
+"#]],
+        str![[r#"
+
 running 8 tests
 ...
 failures:
@@ -722,6 +1031,7 @@ failures:
 
 test result: FAILED. 2 passed; 1 failed; 5 ignored; 0 filtered out; finished in [..]s
 
-"#,
+
+"#]],
     );
 }
diff --git a/crates/libtest2-mimic/tests/testsuite/panic.rs b/crates/libtest2-mimic/tests/testsuite/panic.rs
index e4006bf..9d2db79 100644
--- a/crates/libtest2-mimic/tests/testsuite/panic.rs
+++ b/crates/libtest2-mimic/tests/testsuite/panic.rs
@@ -1,3 +1,6 @@
+use snapbox::prelude::*;
+use snapbox::str;
+
 fn test_cmd() -> snapbox::cmd::Command {
     static BIN: once_cell_polyfill::sync::OnceLock<(std::path::PathBuf, std::path::PathBuf)> =
         once_cell_polyfill::sync::OnceLock::new();
@@ -22,7 +25,7 @@ fn main() {
     snapbox::cmd::Command::new(bin).current_dir(current_dir)
 }
 
-fn check(args: &[&str], code: i32, single: &str, parallel: &str) {
+fn check(args: &[&str], code: i32, single: impl IntoData, parallel: impl IntoData) {
     test_cmd()
         .args(args)
         .args(["--test-threads", "1"])
@@ -41,7 +44,8 @@ fn normal() {
     check(
         &[],
         101,
-        r#"
+        str![[r#"
+
 running 2 tests
 test panics ... FAILED
 test passes ... ok
@@ -57,8 +61,10 @@ failures:
 
 test result: FAILED. 1 passed; 1 failed; 0 ignored; 0 filtered out; finished in [..]s
 
-"#,
-        r#"
+
+"#]],
+        str![[r#"
+
 running 2 tests
 ...
 
@@ -73,6 +79,7 @@ failures:
 
 test result: FAILED. 1 passed; 1 failed; 0 ignored; 0 filtered out; finished in [..]s
 
-"#,
+
+"#]],
     );
 }
diff --git a/crates/libtest2/Cargo.toml b/crates/libtest2/Cargo.toml
index ca33579..cac52b8 100644
--- a/crates/libtest2/Cargo.toml
+++ b/crates/libtest2/Cargo.toml
@@ -37,7 +37,7 @@ dunce = "1.0.4"
 escargot = "0.5.8"
 once_cell_polyfill = "1.56.0"
 pathdiff = "0.2.1"
-snapbox = "0.6.0"
+snapbox = { version = "0.6.0", features = ["json"] }
 
 [lints]
 workspace = true
diff --git a/crates/libtest2/tests/testsuite/all_passing.rs b/crates/libtest2/tests/testsuite/all_passing.rs
index 912b529..38586a4 100644
--- a/crates/libtest2/tests/testsuite/all_passing.rs
+++ b/crates/libtest2/tests/testsuite/all_passing.rs
@@ -1,3 +1,6 @@
+use snapbox::prelude::*;
+use snapbox::str;
+
 fn test_cmd() -> snapbox::cmd::Command {
     static BIN: once_cell_polyfill::sync::OnceLock<(std::path::PathBuf, std::path::PathBuf)> =
         once_cell_polyfill::sync::OnceLock::new();
@@ -26,7 +29,7 @@ fn barro(_state: &libtest2::State) -> libtest2::RunResult {
     snapbox::cmd::Command::new(bin).current_dir(current_dir)
 }
 
-fn check(args: &[&str], single: &str, parallel: &str) {
+fn check(args: &[&str], single: impl IntoData, parallel: impl IntoData) {
     test_cmd()
         .args(args)
         .args(["--test-threads", "1"])
@@ -40,7 +43,8 @@ fn check(args: &[&str], single: &str, parallel: &str) {
 fn normal() {
     check(
         &[],
-        r#"
+        str![[r#"
+
 running 3 tests
 test bar   ... ok
 test barro ... ok
@@ -48,14 +52,17 @@ test foo   ... ok
 
 test result: ok. 3 passed; 0 failed; 0 ignored; 0 filtered out; finished in [..]s
 
-"#,
-        r#"
+
+"#]],
+        str![[r#"
+
 running 3 tests
 ...
 
 test result: ok. 3 passed; 0 failed; 0 ignored; 0 filtered out; finished in [..]s
 
-"#,
+
+"#]],
     );
 }
 
@@ -63,20 +70,24 @@ test result: ok. 3 passed; 0 failed; 0 ignored; 0 filtered out; finished in [..]
 fn filter_one() {
     check(
         &["foo"],
-        r#"
+        str![[r#"
+
 running 1 test
 test foo ... ok
 
 test result: ok. 1 passed; 0 failed; 0 ignored; 2 filtered out; finished in [..]s
 
-"#,
-        r#"
+
+"#]],
+        str![[r#"
+
 running 1 test
 test foo ... ok
 
 test result: ok. 1 passed; 0 failed; 0 ignored; 2 filtered out; finished in [..]s
 
-"#,
+
+"#]],
     );
 }
 
@@ -84,21 +95,25 @@ test result: ok. 1 passed; 0 failed; 0 ignored; 2 filtered out; finished in [..]
 fn filter_two() {
     check(
         &["bar"],
-        r#"
+        str![[r#"
+
 running 2 tests
 test bar   ... ok
 test barro ... ok
 
 test result: ok. 2 passed; 0 failed; 0 ignored; 1 filtered out; finished in [..]s
 
-"#,
-        r#"
+
+"#]],
+        str![[r#"
+
 running 2 tests
 ...
 
 test result: ok. 2 passed; 0 failed; 0 ignored; 1 filtered out; finished in [..]s
 
-"#,
+
+"#]],
     );
 }
 
@@ -106,20 +121,24 @@ test result: ok. 2 passed; 0 failed; 0 ignored; 1 filtered out; finished in [..]
 fn filter_exact() {
     check(
         &["bar", "--exact"],
-        r#"
+        str![[r#"
+
 running 1 test
 test bar ... ok
 
 test result: ok. 1 passed; 0 failed; 0 ignored; 2 filtered out; finished in [..]s
 
-"#,
-        r#"
+
+"#]],
+        str![[r#"
+
 running 1 test
 test bar ... ok
 
 test result: ok. 1 passed; 0 failed; 0 ignored; 2 filtered out; finished in [..]s
 
-"#,
+
+"#]],
     );
 }
 
@@ -127,20 +146,24 @@ test result: ok. 1 passed; 0 failed; 0 ignored; 2 filtered out; finished in [..]
 fn filter_two_and_skip() {
     check(
         &["--skip", "barro", "bar"],
-        r#"
+        str![[r#"
+
 running 1 test
 test bar ... ok
 
 test result: ok. 1 passed; 0 failed; 0 ignored; 2 filtered out; finished in [..]s
 
-"#,
-        r#"
+
+"#]],
+        str![[r#"
+
 running 1 test
 test bar ... ok
 
 test result: ok. 1 passed; 0 failed; 0 ignored; 2 filtered out; finished in [..]s
 
-"#,
+
+"#]],
     );
 }
 
@@ -148,7 +171,8 @@ test result: ok. 1 passed; 0 failed; 0 ignored; 2 filtered out; finished in [..]
 fn skip_nothing() {
     check(
         &["--skip", "peter"],
-        r#"
+        str![[r#"
+
 running 3 tests
 test bar   ... ok
 test barro ... ok
@@ -156,14 +180,17 @@ test foo   ... ok
 
 test result: ok. 3 passed; 0 failed; 0 ignored; 0 filtered out; finished in [..]s
 
-"#,
-        r#"
+
+"#]],
+        str![[r#"
+
 running 3 tests
 ...
 
 test result: ok. 3 passed; 0 failed; 0 ignored; 0 filtered out; finished in [..]s
 
-"#,
+
+"#]],
     );
 }
 
@@ -171,20 +198,24 @@ test result: ok. 3 passed; 0 failed; 0 ignored; 0 filtered out; finished in [..]
 fn skip_two() {
     check(
         &["--skip", "bar"],
-        r#"
+        str![[r#"
+
 running 1 test
 test foo ... ok
 
 test result: ok. 1 passed; 0 failed; 0 ignored; 2 filtered out; finished in [..]s
 
-"#,
-        r#"
+
+"#]],
+        str![[r#"
+
 running 1 test
 test foo ... ok
 
 test result: ok. 1 passed; 0 failed; 0 ignored; 2 filtered out; finished in [..]s
 
-"#,
+
+"#]],
     );
 }
 
@@ -192,21 +223,25 @@ test result: ok. 1 passed; 0 failed; 0 ignored; 2 filtered out; finished in [..]
 fn skip_exact() {
     check(
         &["--exact", "--skip", "bar"],
-        r#"
+        str![[r#"
+
 running 2 tests
 test barro ... ok
 test foo   ... ok
 
 test result: ok. 2 passed; 0 failed; 0 ignored; 1 filtered out; finished in [..]s
 
-"#,
-        r#"
+
+"#]],
+        str![[r#"
+
 running 2 tests
 ...
 
 test result: ok. 2 passed; 0 failed; 0 ignored; 1 filtered out; finished in [..]s
 
-"#,
+
+"#]],
     );
 }
 
@@ -214,17 +249,21 @@ test result: ok. 2 passed; 0 failed; 0 ignored; 1 filtered out; finished in [..]
 fn terse_output() {
     check(
         &["--quiet", "--skip", "foo"],
-        r#"
+        str![[r#"
+
 running 2 tests
 ..
 test result: ok. 2 passed; 0 failed; 0 ignored; 1 filtered out; finished in [..]s
 
-"#,
-        r#"
+
+"#]],
+        str![[r#"
+
 running 2 tests
 ..
 test result: ok. 2 passed; 0 failed; 0 ignored; 1 filtered out; finished in [..]s
 
-"#,
+
+"#]],
     );
 }
diff --git a/crates/libtest2/tests/testsuite/mixed_bag.rs b/crates/libtest2/tests/testsuite/mixed_bag.rs
index c845b76..18346c8 100644
--- a/crates/libtest2/tests/testsuite/mixed_bag.rs
+++ b/crates/libtest2/tests/testsuite/mixed_bag.rs
@@ -1,3 +1,6 @@
+use snapbox::prelude::*;
+use snapbox::str;
+
 fn test_cmd() -> snapbox::cmd::Command {
     static BIN: once_cell_polyfill::sync::OnceLock<(std::path::PathBuf, std::path::PathBuf)> =
         once_cell_polyfill::sync::OnceLock::new();
@@ -51,7 +54,7 @@ fn bear(state: &libtest2::State) -> libtest2::RunResult {
     snapbox::cmd::Command::new(bin).current_dir(current_dir)
 }
 
-fn check(args: &[&str], code: i32, single: &str, parallel: &str) {
+fn check(args: &[&str], code: i32, single: impl IntoData, parallel: impl IntoData) {
     test_cmd()
         .args(args)
         .args(["--test-threads", "1"])
@@ -70,7 +73,8 @@ fn normal() {
     check(
         &[],
         101,
-        r#"
+        str![[r#"
+
 running 8 tests
 test bear  ... ignored
 test bunny ... ignored
@@ -92,8 +96,10 @@ failures:
 
 test result: FAILED. 2 passed; 1 failed; 5 ignored; 0 filtered out; finished in [..]s
 
-"#,
-        r#"
+
+"#]],
+        str![[r#"
+
 running 8 tests
 ...
 
@@ -108,7 +114,8 @@ failures:
 
 test result: FAILED. 2 passed; 1 failed; 5 ignored; 0 filtered out; finished in [..]s
 
-"#,
+
+"#]],
     );
 }
 
@@ -117,7 +124,8 @@ fn test_mode() {
     check(
         &["--test"],
         101,
-        r#"
+        str![[r#"
+
 running 8 tests
 test bear  ... ignored
 test bunny ... ignored
@@ -139,8 +147,10 @@ failures:
 
 test result: FAILED. 2 passed; 1 failed; 5 ignored; 0 filtered out; finished in [..]s
 
-"#,
-        r#"
+
+"#]],
+        str![[r#"
+
 running 8 tests
 ...
 
@@ -155,7 +165,8 @@ failures:
 
 test result: FAILED. 2 passed; 1 failed; 5 ignored; 0 filtered out; finished in [..]s
 
-"#,
+
+"#]],
     );
 }
 
@@ -164,7 +175,8 @@ fn bench_mode() {
     check(
         &["--bench"],
         101,
-        r#"
+        str![[r#"
+
 running 8 tests
 test bear  ... ignored
 test bunny ... ignored
@@ -186,8 +198,10 @@ failures:
 
 test result: FAILED. 2 passed; 1 failed; 5 ignored; 0 filtered out; finished in [..]s
 
-"#,
-        r#"
+
+"#]],
+        str![[r#"
+
 running 8 tests
 ...
 
@@ -202,7 +216,8 @@ failures:
 
 test result: FAILED. 2 passed; 1 failed; 5 ignored; 0 filtered out; finished in [..]s
 
-"#,
+
+"#]],
     );
 }
 
@@ -211,7 +226,8 @@ fn list() {
     check(
         &["--list"],
         0,
-        r#"bear: test
+        str![[r#"
+bear: test
 bunny: test
 cat: test
 dog: test
@@ -222,8 +238,10 @@ owl: test
 
 8 tests
 
-"#,
-        r#"bear: test
+
+"#]],
+        str![[r#"
+bear: test
 bunny: test
 cat: test
 dog: test
@@ -234,7 +252,8 @@ owl: test
 
 8 tests
 
-"#,
+
+"#]],
     );
 }
 
@@ -243,7 +262,8 @@ fn list_ignored() {
     check(
         &["--list", "--ignored"],
         0,
-        r#"bear: test
+        str![[r#"
+bear: test
 bunny: test
 cat: test
 dog: test
@@ -254,8 +274,10 @@ owl: test
 
 8 tests
 
-"#,
-        r#"bear: test
+
+"#]],
+        str![[r#"
+bear: test
 bunny: test
 cat: test
 dog: test
@@ -266,7 +288,8 @@ owl: test
 
 8 tests
 
-"#,
+
+"#]],
     );
 }
 
@@ -275,18 +298,22 @@ fn list_with_filter() {
     check(
         &["--list", "a"],
         0,
-        r#"bear: test
+        str![[r#"
+bear: test
 cat: test
 
 2 tests
 
-"#,
-        r#"bear: test
+
+"#]],
+        str![[r#"
+bear: test
 cat: test
 
 2 tests
 
-"#,
+
+"#]],
     );
 }
 
@@ -295,21 +322,25 @@ fn filter_c() {
     check(
         &["a"],
         0,
-        r#"
+        str![[r#"
+
 running 2 tests
 test bear ... ignored
 test cat  ... ok
 
 test result: ok. 1 passed; 0 failed; 1 ignored; 6 filtered out; finished in [..]s
 
-"#,
-        r#"
+
+"#]],
+        str![[r#"
+
 running 2 tests
 ...
 
 test result: ok. 1 passed; 0 failed; 1 ignored; 6 filtered out; finished in [..]s
 
-"#,
+
+"#]],
     );
 }
 
@@ -318,21 +349,25 @@ fn filter_o_test() {
     check(
         &["--test", "a"],
         0,
-        r#"
+        str![[r#"
+
 running 2 tests
 test bear ... ignored
 test cat  ... ok
 
 test result: ok. 1 passed; 0 failed; 1 ignored; 6 filtered out; finished in [..]s
 
-"#,
-        r#"
+
+"#]],
+        str![[r#"
+
 running 2 tests
 ...
 
 test result: ok. 1 passed; 0 failed; 1 ignored; 6 filtered out; finished in [..]s
 
-"#,
+
+"#]],
     );
 }
 
@@ -341,7 +376,8 @@ fn filter_o_test_include_ignored() {
     check(
         &["--test", "--include-ignored", "o"],
         101,
-        r#"
+        str![[r#"
+
 running 4 tests
 test dog  ... FAILED
 test fox  ... ok
@@ -363,8 +399,10 @@ failures:
 
 test result: FAILED. 2 passed; 2 failed; 0 ignored; 4 filtered out; finished in [..]s
 
-"#,
-        r#"
+
+"#]],
+        str![[r#"
+
 running 4 tests
 ...
 
@@ -383,7 +421,8 @@ failures:
 
 test result: FAILED. 2 passed; 2 failed; 0 ignored; 4 filtered out; finished in [..]s
 
-"#,
+
+"#]],
     );
 }
 
@@ -392,7 +431,8 @@ fn filter_o_test_ignored() {
     check(
         &["--test", "--ignored", "o"],
         101,
-        r#"
+        str![[r#"
+
 running 4 tests
 test dog  ... FAILED
 test fox  ... ok
@@ -414,8 +454,10 @@ failures:
 
 test result: FAILED. 2 passed; 2 failed; 0 ignored; 4 filtered out; finished in [..]s
 
-"#,
-        r#"
+
+"#]],
+        str![[r#"
+
 running 4 tests
 ...
 
@@ -434,7 +476,8 @@ failures:
 
 test result: FAILED. 2 passed; 2 failed; 0 ignored; 4 filtered out; finished in [..]s
 
-"#,
+
+"#]],
     );
 }
 
@@ -443,7 +486,8 @@ fn normal_include_ignored() {
     check(
         &["--include-ignored"],
         101,
-        r#"
+        str![[r#"
+
 running 8 tests
 test bear  ... FAILED
 test bunny ... FAILED
@@ -477,8 +521,10 @@ failures:
 
 test result: FAILED. 4 passed; 4 failed; 0 ignored; 0 filtered out; finished in [..]s
 
-"#,
-        r#"
+
+"#]],
+        str![[r#"
+
 running 8 tests
 ...
 
@@ -505,7 +551,8 @@ failures:
 
 test result: FAILED. 4 passed; 4 failed; 0 ignored; 0 filtered out; finished in [..]s
 
-"#,
+
+"#]],
     );
 }
 
@@ -514,7 +561,8 @@ fn normal_ignored() {
     check(
         &["--ignored"],
         101,
-        r#"
+        str![[r#"
+
 running 8 tests
 test bear  ... FAILED
 test bunny ... FAILED
@@ -548,8 +596,10 @@ failures:
 
 test result: FAILED. 4 passed; 4 failed; 0 ignored; 0 filtered out; finished in [..]s
 
-"#,
-        r#"
+
+"#]],
+        str![[r#"
+
 running 8 tests
 ...
 
@@ -576,7 +626,8 @@ failures:
 
 test result: FAILED. 4 passed; 4 failed; 0 ignored; 0 filtered out; finished in [..]s
 
-"#,
+
+"#]],
     );
 }
 
@@ -585,7 +636,8 @@ fn lots_of_flags() {
     check(
         &["--ignored", "--skip", "g", "--test", "o"],
         101,
-        r#"
+        str![[r#"
+
 running 2 tests
 test fox ... ok
 test owl ... FAILED
@@ -601,8 +653,10 @@ failures:
 
 test result: FAILED. 1 passed; 1 failed; 0 ignored; 6 filtered out; finished in [..]s
 
-"#,
-        r#"
+
+"#]],
+        str![[r#"
+
 running 2 tests
 ...
 
@@ -617,7 +671,8 @@ failures:
 
 test result: FAILED. 1 passed; 1 failed; 0 ignored; 6 filtered out; finished in [..]s
 
-"#,
+
+"#]],
     );
 }
 
@@ -627,28 +682,128 @@ fn list_json() {
     check(
         &["-Zunstable-options", "--format=json", "--list", "a"],
         0,
-        r#"{"event":"discover-start"}
-{"event":"discover-case","name":"bear","mode":"test","run":true}
-{"event":"discover-case","name":"bunny","mode":"test","run":false}
-{"event":"discover-case","name":"cat","mode":"test","run":true}
-{"event":"discover-case","name":"dog","mode":"test","run":false}
-{"event":"discover-case","name":"fly","mode":"test","run":false}
-{"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":"[..]"}
-"#,
-        r#"{"event":"discover-start"}
-{"event":"discover-case","name":"bear","mode":"test","run":true}
-{"event":"discover-case","name":"bunny","mode":"test","run":false}
-{"event":"discover-case","name":"cat","mode":"test","run":true}
-{"event":"discover-case","name":"dog","mode":"test","run":false}
-{"event":"discover-case","name":"fly","mode":"test","run":false}
-{"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":"[..]"}
-"#,
+        str![[r#"
+[
+  {
+    "event": "discover-start"
+  },
+  {
+    "event": "discover-case",
+    "mode": "test",
+    "name": "bear",
+    "run": true
+  },
+  {
+    "event": "discover-case",
+    "mode": "test",
+    "name": "bunny",
+    "run": false
+  },
+  {
+    "event": "discover-case",
+    "mode": "test",
+    "name": "cat",
+    "run": true
+  },
+  {
+    "event": "discover-case",
+    "mode": "test",
+    "name": "dog",
+    "run": false
+  },
+  {
+    "event": "discover-case",
+    "mode": "test",
+    "name": "fly",
+    "run": false
+  },
+  {
+    "event": "discover-case",
+    "mode": "test",
+    "name": "fox",
+    "run": false
+  },
+  {
+    "event": "discover-case",
+    "mode": "test",
+    "name": "frog",
+    "run": false
+  },
+  {
+    "event": "discover-case",
+    "mode": "test",
+    "name": "owl",
+    "run": false
+  },
+  {
+    "elapsed_s": "[..]",
+    "event": "discover-complete"
+  }
+]
+"#]]
+        .is_json()
+        .against_jsonlines(),
+        str![[r#"
+[
+  {
+    "event": "discover-start"
+  },
+  {
+    "event": "discover-case",
+    "mode": "test",
+    "name": "bear",
+    "run": true
+  },
+  {
+    "event": "discover-case",
+    "mode": "test",
+    "name": "bunny",
+    "run": false
+  },
+  {
+    "event": "discover-case",
+    "mode": "test",
+    "name": "cat",
+    "run": true
+  },
+  {
+    "event": "discover-case",
+    "mode": "test",
+    "name": "dog",
+    "run": false
+  },
+  {
+    "event": "discover-case",
+    "mode": "test",
+    "name": "fly",
+    "run": false
+  },
+  {
+    "event": "discover-case",
+    "mode": "test",
+    "name": "fox",
+    "run": false
+  },
+  {
+    "event": "discover-case",
+    "mode": "test",
+    "name": "frog",
+    "run": false
+  },
+  {
+    "event": "discover-case",
+    "mode": "test",
+    "name": "owl",
+    "run": false
+  },
+  {
+    "elapsed_s": "[..]",
+    "event": "discover-complete"
+  }
+]
+"#]]
+        .is_json()
+        .against_jsonlines(),
     );
 }
 
@@ -658,40 +813,191 @@ fn test_json() {
     check(
         &["-Zunstable-options", "--format=json", "a"],
         0,
-        r#"{"event":"discover-start"}
-{"event":"discover-case","name":"bear","mode":"test","run":true}
-{"event":"discover-case","name":"bunny","mode":"test","run":false}
-{"event":"discover-case","name":"cat","mode":"test","run":true}
-{"event":"discover-case","name":"dog","mode":"test","run":false}
-{"event":"discover-case","name":"fly","mode":"test","run":false}
-{"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":"[..]"}
-{"event":"suite-start"}
-{"event":"case-start","name":"bear"}
-{"event":"case-complete","name":"bear","mode":"test","status":"ignored","message":"fails","elapsed_s":"[..]"}
-{"event":"case-start","name":"cat"}
-{"event":"case-complete","name":"cat","mode":"test","status":null,"message":null,"elapsed_s":"[..]"}
-{"event":"suite-complete","elapsed_s":"[..]"}
-"#,
-        r#"{"event":"discover-start"}
-{"event":"discover-case","name":"bear","mode":"test","run":true}
-{"event":"discover-case","name":"bunny","mode":"test","run":false}
-{"event":"discover-case","name":"cat","mode":"test","run":true}
-{"event":"discover-case","name":"dog","mode":"test","run":false}
-{"event":"discover-case","name":"fly","mode":"test","run":false}
-{"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":"[..]"}
-{"event":"suite-start"}
-[..]
-[..]
-[..]
-[..]
-{"event":"suite-complete","elapsed_s":"[..]"}
-"#,
+        str![[r#"
+[
+  {
+    "event": "discover-start"
+  },
+  {
+    "event": "discover-case",
+    "mode": "test",
+    "name": "bear",
+    "run": true
+  },
+  {
+    "event": "discover-case",
+    "mode": "test",
+    "name": "bunny",
+    "run": false
+  },
+  {
+    "event": "discover-case",
+    "mode": "test",
+    "name": "cat",
+    "run": true
+  },
+  {
+    "event": "discover-case",
+    "mode": "test",
+    "name": "dog",
+    "run": false
+  },
+  {
+    "event": "discover-case",
+    "mode": "test",
+    "name": "fly",
+    "run": false
+  },
+  {
+    "event": "discover-case",
+    "mode": "test",
+    "name": "fox",
+    "run": false
+  },
+  {
+    "event": "discover-case",
+    "mode": "test",
+    "name": "frog",
+    "run": false
+  },
+  {
+    "event": "discover-case",
+    "mode": "test",
+    "name": "owl",
+    "run": false
+  },
+  {
+    "elapsed_s": "[..]",
+    "event": "discover-complete"
+  },
+  {
+    "event": "suite-start"
+  },
+  {
+    "event": "case-start",
+    "name": "bear"
+  },
+  {
+    "elapsed_s": "[..]",
+    "event": "case-complete",
+    "message": "fails",
+    "mode": "test",
+    "name": "bear",
+    "status": "ignored"
+  },
+  {
+    "event": "case-start",
+    "name": "cat"
+  },
+  {
+    "elapsed_s": "[..]",
+    "event": "case-complete",
+    "message": null,
+    "mode": "test",
+    "name": "cat",
+    "status": null
+  },
+  {
+    "elapsed_s": "[..]",
+    "event": "suite-complete"
+  }
+]
+"#]]
+        .is_json()
+        .against_jsonlines(),
+        str![[r#"
+[
+  {
+    "event": "discover-start"
+  },
+  {
+    "event": "discover-case",
+    "mode": "test",
+    "name": "bear",
+    "run": true
+  },
+  {
+    "event": "discover-case",
+    "mode": "test",
+    "name": "bunny",
+    "run": false
+  },
+  {
+    "event": "discover-case",
+    "mode": "test",
+    "name": "cat",
+    "run": true
+  },
+  {
+    "event": "discover-case",
+    "mode": "test",
+    "name": "dog",
+    "run": false
+  },
+  {
+    "event": "discover-case",
+    "mode": "test",
+    "name": "fly",
+    "run": false
+  },
+  {
+    "event": "discover-case",
+    "mode": "test",
+    "name": "fox",
+    "run": false
+  },
+  {
+    "event": "discover-case",
+    "mode": "test",
+    "name": "frog",
+    "run": false
+  },
+  {
+    "event": "discover-case",
+    "mode": "test",
+    "name": "owl",
+    "run": false
+  },
+  {
+    "elapsed_s": "[..]",
+    "event": "discover-complete"
+  },
+  {
+    "event": "suite-start"
+  },
+  {
+    "event": "case-start",
+    "name": "bear"
+  },
+  {
+    "elapsed_s": "[..]",
+    "event": "case-complete",
+    "message": "fails",
+    "mode": "test",
+    "name": "bear",
+    "status": "ignored"
+  },
+  {
+    "event": "case-start",
+    "name": "cat"
+  },
+  {
+    "elapsed_s": "[..]",
+    "event": "case-complete",
+    "message": null,
+    "mode": "test",
+    "name": "cat",
+    "status": null
+  },
+  {
+    "elapsed_s": "[..]",
+    "event": "suite-complete"
+  }
+]
+"#]]
+        .unordered()
+        .is_json()
+        .against_jsonlines(),
     );
 }
 
@@ -700,7 +1006,8 @@ fn terse_output() {
     check(
         &["--quiet"],
         101,
-        r#"
+        str![[r#"
+
 running 8 tests
 ii.Fi.ii
 failures:
@@ -714,8 +1021,10 @@ failures:
 
 test result: FAILED. 2 passed; 1 failed; 5 ignored; 0 filtered out; finished in [..]s
 
-"#,
-        r#"
+
+"#]],
+        str![[r#"
+
 running 8 tests
 ...
 failures:
@@ -729,6 +1038,7 @@ failures:
 
 test result: FAILED. 2 passed; 1 failed; 5 ignored; 0 filtered out; finished in [..]s
 
-"#,
+
+"#]],
     );
 }
diff --git a/crates/libtest2/tests/testsuite/panic.rs b/crates/libtest2/tests/testsuite/panic.rs
index a9af8bf..0c786a3 100644
--- a/crates/libtest2/tests/testsuite/panic.rs
+++ b/crates/libtest2/tests/testsuite/panic.rs
@@ -1,3 +1,6 @@
+use snapbox::prelude::*;
+use snapbox::str;
+
 fn test_cmd() -> snapbox::cmd::Command {
     static BIN: once_cell_polyfill::sync::OnceLock<(std::path::PathBuf, std::path::PathBuf)> =
         once_cell_polyfill::sync::OnceLock::new();
@@ -22,7 +25,7 @@ fn panics(_state: &libtest2::State) -> libtest2::RunResult {
     snapbox::cmd::Command::new(bin).current_dir(current_dir)
 }
 
-fn check(args: &[&str], code: i32, single: &str, parallel: &str) {
+fn check(args: &[&str], code: i32, single: impl IntoData, parallel: impl IntoData) {
     test_cmd()
         .args(args)
         .args(["--test-threads", "1"])
@@ -41,7 +44,8 @@ fn normal() {
     check(
         &[],
         101,
-        r#"
+        str![[r#"
+
 running 2 tests
 test panics ... FAILED
 test passes ... ok
@@ -57,8 +61,10 @@ failures:
 
 test result: FAILED. 1 passed; 1 failed; 0 ignored; 0 filtered out; finished in [..]s
 
-"#,
-        r#"
+
+"#]],
+        str![[r#"
+
 running 2 tests
 ...
 
@@ -73,6 +79,7 @@ failures:
 
 test result: FAILED. 1 passed; 1 failed; 0 ignored; 0 filtered out; finished in [..]s
 
-"#,
+
+"#]],
     );
 }

From f285ae40a76b966079f7b834bfa5f3ae8fb46d99 Mon Sep 17 00:00:00 2001
From: Ed Page <eopage@gmail.com>
Date: Thu, 10 Jul 2025 16:45:10 -0500
Subject: [PATCH 2/3] test: Show list ordering behavior

---
 .../tests/testsuite/mixed_bag.rs              | 28 +++++++++++++++++++
 crates/libtest2/tests/testsuite/mixed_bag.rs  | 28 +++++++++++++++++++
 2 files changed, 56 insertions(+)

diff --git a/crates/libtest2-mimic/tests/testsuite/mixed_bag.rs b/crates/libtest2-mimic/tests/testsuite/mixed_bag.rs
index 49c16d2..03fc1c5 100644
--- a/crates/libtest2-mimic/tests/testsuite/mixed_bag.rs
+++ b/crates/libtest2-mimic/tests/testsuite/mixed_bag.rs
@@ -306,6 +306,34 @@ cat: test
 2 tests
 
 
+"#]],
+    );
+}
+
+#[test]
+fn list_with_specified_order() {
+    check(
+        &["--list", "--exact", "owl", "fox", "bunny", "frog"],
+        0,
+        str![[r#"
+bunny: test
+fox: test
+frog: test
+owl: test
+
+4 tests
+
+
+"#]],
+        str![[r#"
+bunny: test
+fox: test
+frog: test
+owl: test
+
+4 tests
+
+
 "#]],
     );
 }
diff --git a/crates/libtest2/tests/testsuite/mixed_bag.rs b/crates/libtest2/tests/testsuite/mixed_bag.rs
index 18346c8..2e7694d 100644
--- a/crates/libtest2/tests/testsuite/mixed_bag.rs
+++ b/crates/libtest2/tests/testsuite/mixed_bag.rs
@@ -313,6 +313,34 @@ cat: test
 2 tests
 
 
+"#]],
+    );
+}
+
+#[test]
+fn list_with_specified_order() {
+    check(
+        &["--list", "--exact", "owl", "fox", "bunny", "frog"],
+        0,
+        str![[r#"
+bunny: test
+fox: test
+frog: test
+owl: test
+
+4 tests
+
+
+"#]],
+        str![[r#"
+bunny: test
+fox: test
+frog: test
+owl: test
+
+4 tests
+
+
 "#]],
     );
 }

From b9036a323fa53b1cea3b63700d7d0452b0827553 Mon Sep 17 00:00:00 2001
From: Ed Page <eopage@gmail.com>
Date: Thu, 10 Jul 2025 17:02:29 -0500
Subject: [PATCH 3/3] feat(harness): Give users control over sort order

---
 DESIGN.md                                     |  7 ++
 crates/libtest2-harness/src/harness.rs        | 17 +++-
 .../tests/testsuite/mixed_bag.rs              | 80 +++++++++----------
 crates/libtest2/tests/testsuite/mixed_bag.rs  | 80 +++++++++----------
 4 files changed, 101 insertions(+), 83 deletions(-)

diff --git a/DESIGN.md b/DESIGN.md
index 88a78f3..6bfb3b0 100644
--- a/DESIGN.md
+++ b/DESIGN.md
@@ -149,3 +149,10 @@ support for multi-character shorts is something people may want to opt-in to (it
 Performance isn't the top priority, so remoing `&str` -> `char` conversions isn't necessarily viewed as a benefit.
 This also makes `match` need to work off of `&str` instead of `char`.
 Unsure which of those would be slower and how the different characteristics match up.
+
+## Harness
+
+### Decision: report and run tests in filter order
+
+Rather than build into every harness shuffle, sharding, and any other specific logic like that,
+we can instead give the user direct control over the test order by the order they are specified on the command line.
diff --git a/crates/libtest2-harness/src/harness.rs b/crates/libtest2-harness/src/harness.rs
index 6b4cc0e..3abc016 100644
--- a/crates/libtest2-harness/src/harness.rs
+++ b/crates/libtest2-harness/src/harness.rs
@@ -161,9 +161,6 @@ fn discover(
     notifier.notify(notify::Event::DiscoverStart)?;
     let timer = std::time::Instant::now();
 
-    // Do this first so it applies to both discover and running
-    cases.sort_unstable_by_key(|case| case.name().to_owned());
-
     let matches_filter = |case: &dyn Case, filter: &str| {
         let test_name = case.name();
 
@@ -172,6 +169,20 @@ fn discover(
             false => test_name.contains(filter),
         }
     };
+
+    // Do this first so it applies to both discover and running
+    cases.sort_unstable_by_key(|case| {
+        let priority = if opts.filters.is_empty() {
+            Some(0)
+        } else {
+            opts.filters
+                .iter()
+                .position(|filter| matches_filter(case.as_ref(), filter))
+        };
+        let name = case.name().to_owned();
+        (priority, name)
+    });
+
     let mut retain_cases = Vec::with_capacity(cases.len());
     for case in cases.iter() {
         let filtered_in = opts.filters.is_empty()
diff --git a/crates/libtest2-mimic/tests/testsuite/mixed_bag.rs b/crates/libtest2-mimic/tests/testsuite/mixed_bag.rs
index 03fc1c5..b95d7eb 100644
--- a/crates/libtest2-mimic/tests/testsuite/mixed_bag.rs
+++ b/crates/libtest2-mimic/tests/testsuite/mixed_bag.rs
@@ -316,20 +316,20 @@ fn list_with_specified_order() {
         &["--list", "--exact", "owl", "fox", "bunny", "frog"],
         0,
         str![[r#"
-bunny: test
+owl: test
 fox: test
+bunny: test
 frog: test
-owl: test
 
 4 tests
 
 
 "#]],
         str![[r#"
-bunny: test
+owl: test
 fox: test
+bunny: test
 frog: test
-owl: test
 
 4 tests
 
@@ -708,24 +708,12 @@ fn list_json() {
   {
     "event": "discover-start"
   },
-  {
-    "event": "discover-case",
-    "mode": "test",
-    "name": "bear",
-    "run": true
-  },
   {
     "event": "discover-case",
     "mode": "test",
     "name": "bunny",
     "run": false
   },
-  {
-    "event": "discover-case",
-    "mode": "test",
-    "name": "cat",
-    "run": true
-  },
   {
     "event": "discover-case",
     "mode": "test",
@@ -756,6 +744,18 @@ fn list_json() {
     "name": "owl",
     "run": false
   },
+  {
+    "event": "discover-case",
+    "mode": "test",
+    "name": "bear",
+    "run": true
+  },
+  {
+    "event": "discover-case",
+    "mode": "test",
+    "name": "cat",
+    "run": true
+  },
   {
     "elapsed_s": "[..]",
     "event": "discover-complete"
@@ -769,24 +769,12 @@ fn list_json() {
   {
     "event": "discover-start"
   },
-  {
-    "event": "discover-case",
-    "mode": "test",
-    "name": "bear",
-    "run": true
-  },
   {
     "event": "discover-case",
     "mode": "test",
     "name": "bunny",
     "run": false
   },
-  {
-    "event": "discover-case",
-    "mode": "test",
-    "name": "cat",
-    "run": true
-  },
   {
     "event": "discover-case",
     "mode": "test",
@@ -817,6 +805,18 @@ fn list_json() {
     "name": "owl",
     "run": false
   },
+  {
+    "event": "discover-case",
+    "mode": "test",
+    "name": "bear",
+    "run": true
+  },
+  {
+    "event": "discover-case",
+    "mode": "test",
+    "name": "cat",
+    "run": true
+  },
   {
     "elapsed_s": "[..]",
     "event": "discover-complete"
@@ -839,24 +839,12 @@ fn test_json() {
   {
     "event": "discover-start"
   },
-  {
-    "event": "discover-case",
-    "mode": "test",
-    "name": "bear",
-    "run": true
-  },
   {
     "event": "discover-case",
     "mode": "test",
     "name": "bunny",
     "run": false
   },
-  {
-    "event": "discover-case",
-    "mode": "test",
-    "name": "cat",
-    "run": true
-  },
   {
     "event": "discover-case",
     "mode": "test",
@@ -887,6 +875,18 @@ fn test_json() {
     "name": "owl",
     "run": false
   },
+  {
+    "event": "discover-case",
+    "mode": "test",
+    "name": "bear",
+    "run": true
+  },
+  {
+    "event": "discover-case",
+    "mode": "test",
+    "name": "cat",
+    "run": true
+  },
   {
     "elapsed_s": "[..]",
     "event": "discover-complete"
diff --git a/crates/libtest2/tests/testsuite/mixed_bag.rs b/crates/libtest2/tests/testsuite/mixed_bag.rs
index 2e7694d..c46391a 100644
--- a/crates/libtest2/tests/testsuite/mixed_bag.rs
+++ b/crates/libtest2/tests/testsuite/mixed_bag.rs
@@ -323,20 +323,20 @@ fn list_with_specified_order() {
         &["--list", "--exact", "owl", "fox", "bunny", "frog"],
         0,
         str![[r#"
-bunny: test
+owl: test
 fox: test
+bunny: test
 frog: test
-owl: test
 
 4 tests
 
 
 "#]],
         str![[r#"
-bunny: test
+owl: test
 fox: test
+bunny: test
 frog: test
-owl: test
 
 4 tests
 
@@ -715,24 +715,12 @@ fn list_json() {
   {
     "event": "discover-start"
   },
-  {
-    "event": "discover-case",
-    "mode": "test",
-    "name": "bear",
-    "run": true
-  },
   {
     "event": "discover-case",
     "mode": "test",
     "name": "bunny",
     "run": false
   },
-  {
-    "event": "discover-case",
-    "mode": "test",
-    "name": "cat",
-    "run": true
-  },
   {
     "event": "discover-case",
     "mode": "test",
@@ -763,6 +751,18 @@ fn list_json() {
     "name": "owl",
     "run": false
   },
+  {
+    "event": "discover-case",
+    "mode": "test",
+    "name": "bear",
+    "run": true
+  },
+  {
+    "event": "discover-case",
+    "mode": "test",
+    "name": "cat",
+    "run": true
+  },
   {
     "elapsed_s": "[..]",
     "event": "discover-complete"
@@ -776,24 +776,12 @@ fn list_json() {
   {
     "event": "discover-start"
   },
-  {
-    "event": "discover-case",
-    "mode": "test",
-    "name": "bear",
-    "run": true
-  },
   {
     "event": "discover-case",
     "mode": "test",
     "name": "bunny",
     "run": false
   },
-  {
-    "event": "discover-case",
-    "mode": "test",
-    "name": "cat",
-    "run": true
-  },
   {
     "event": "discover-case",
     "mode": "test",
@@ -824,6 +812,18 @@ fn list_json() {
     "name": "owl",
     "run": false
   },
+  {
+    "event": "discover-case",
+    "mode": "test",
+    "name": "bear",
+    "run": true
+  },
+  {
+    "event": "discover-case",
+    "mode": "test",
+    "name": "cat",
+    "run": true
+  },
   {
     "elapsed_s": "[..]",
     "event": "discover-complete"
@@ -846,24 +846,12 @@ fn test_json() {
   {
     "event": "discover-start"
   },
-  {
-    "event": "discover-case",
-    "mode": "test",
-    "name": "bear",
-    "run": true
-  },
   {
     "event": "discover-case",
     "mode": "test",
     "name": "bunny",
     "run": false
   },
-  {
-    "event": "discover-case",
-    "mode": "test",
-    "name": "cat",
-    "run": true
-  },
   {
     "event": "discover-case",
     "mode": "test",
@@ -894,6 +882,18 @@ fn test_json() {
     "name": "owl",
     "run": false
   },
+  {
+    "event": "discover-case",
+    "mode": "test",
+    "name": "bear",
+    "run": true
+  },
+  {
+    "event": "discover-case",
+    "mode": "test",
+    "name": "cat",
+    "run": true
+  },
   {
     "elapsed_s": "[..]",
     "event": "discover-complete"