test: run the full content-root tests only where they matter

The five mod_content tests that load the whole content root took minutes of
every `cargo test -p horizon-client --lib` on prepared data. They are now
#[ignore]d; pr_ready runs them when the diff touches what they load, and CI's
verify job runs them filtered with --ignored on its existing build.

Co-Authored-By: Claude Opus 5.5 <[email protected]>

.github/workflows/ci.yml

@@ -72,6 +72,9 @@ jobs:
         if: steps.rust.outputs.required != 'false'
         run: |
           cargo +stable test --workspace --lib --bins --tests --features horizon-client/mods,horizon-mods/pack
+          # The full content-root tests (#[ignore]d: minutes each on a laptop). The same build as above; they need the
+          # prepared vanilla data, so without it they pass at once.
+          cargo +stable test --workspace --lib --features horizon-client/mods,horizon-mods/pack mod_content::tests:: -- --ignored
           cargo +stable test --workspace --doc --features horizon-client/mods,horizon-mods/pack
   # The launcher is its own workspace (launcher/Cargo.toml), so verify's cargo runs never build it. A pull request that
   # changes it or a crate it builds is checked here, and so is every push to main: two pull requests can each pass

AGENTS.md

@@ -66,6 +66,7 @@ reads `README.md`, `launcher/links.json`, `docs/api/`, `roadmap/roadmap.json` an
 python3 tools/pr_ready.py                  # the self-check: fmt, clippy -D warnings, touched crates' tests, harnesses; paste its block in the PR
 python3 tools/pr_ready.py --quick          # same without harnesses
 cargo test -p horizon-client --lib --bins --tests   # skips the 104 examples (pr_ready does this); `--doc` separately
+cargo test -p horizon-client --features horizon-client/mods --lib mod_content::tests:: -- --ignored   # the 5 slow content-root tests, #[ignore]d; pr_ready runs them when mod content, assets, blocks or items change
 cargo build --profile fast -p horizon-client        # optimized, quick to link: use it to play or run lan_e2e
 python3 tools/parity.py --changed origin/main       # the harnesses your branch can affect (CI's parity job)
 python3 tools/parity.py --changed-files paths.txt --list   # which harnesses cover these files, without running them

crates/horizon-client/src/mod_content_tests.rs

@@ -114,6 +114,7 @@ fn ruby_mod(dir: &Path) -> ContentMod {
 /// new blocks behave like their templates with the overrides, and vanilla's
 /// states are where they were.
 #[test]
+#[ignore = "full content root: CI and pr_ready run it"]
 fn content_root_loads_with_every_table() {
     let Some(base) = prepared() else {
         return;
@@ -352,6 +353,7 @@ fn no_content_keeps_the_base_root() {
 use horizon_world::registry::BlockStateId;
 
 #[test]
+#[ignore = "full content root: CI and pr_ready run it"]
 fn shared_behaviour_document_matches_independent_loaders() {
     let Some(root) = prepared() else { return };
     let assets = Assets::load(&root).expect("assets");
@@ -414,6 +416,7 @@ fn shared_behaviour_document_matches_independent_loaders() {
 
 #[cfg(unix)]
 #[test]
+#[ignore = "full content root: CI and pr_ready run it"]
 fn independent_reloads_read_changed_behaviour_json_and_report_invalid_files() {
     let Some(base) = prepared() else { return };
     let scratch = std::env::temp_dir().join(format!("horizon-json-reloads-{}", std::process::id()));
@@ -535,6 +538,7 @@ fn independent_reloads_read_changed_behaviour_json_and_report_invalid_files() {
 /// A built root is kept for later starts, and built again when a mod's
 /// files change.
 #[test]
+#[ignore = "full content root: CI and pr_ready run it"]
 fn content_root_is_reused_until_a_mod_changes() {
     let Some(base) = prepared() else {
         return;
@@ -571,6 +575,7 @@ fn content_root_is_reused_until_a_mod_changes() {
 /// set, pool and templates join the bundles, and its biome tag keeps only
 /// what the loader knows.
 #[test]
+#[ignore = "full content root: CI and pr_ready run it"]
 fn content_root_carries_a_structure_mod() {
     let Some(base) = prepared() else {
         return;

tests/test_pr_ready.py

@@ -56,6 +56,19 @@ class PrReadyTests(unittest.TestCase):
         self.assertEqual(by_name["doc tests"].command, "cargo test --locked -p horizon-client --doc")
         self.assertIsNone(by_name["doc tests"].status)
 
+    def test_content_root_tests_run_only_when_what_they_load_changes(self):
+        def content_step(path):
+            with mock.patch.object(pr_ready, "affected_here", return_value=[]):
+                steps = pr_ready.plan(args(quick=True), "origin/main", {path}, PACKAGES, LIBRARIES, DEPENDENCIES)
+            return {step.name: step for step in steps}["content root tests"]
+        self.assertEqual(content_step("crates/horizon-client/src/game.rs").skip, "content root untouched")
+        for path in ["crates/horizon-client/src/mod_content.rs", "crates/horizon-client/src/mod_content_tests.rs",
+                     "crates/horizon-mods/src/content.rs", "crates/horizon-assets/src/lib.rs", "Cargo.lock"]:
+            with self.subTest(path=path):
+                step = content_step(path)
+                self.assertIsNone(step.skip)
+                self.assertEqual(step.command, pr_ready.CONTENT_ROOT_TESTS)
+
     def test_shared_rust_configuration_keeps_workspace_coverage(self):
         for path in sorted(pr_ready.ROOT_RUST | {".cargo/config.toml", "crates/unknown/src/lib.rs"}):
             with self.subTest(path=path), mock.patch.object(pr_ready, "affected_here", return_value=[]):

tools/pr_ready.py

@@ -290,6 +290,14 @@ def mod_features(crates):
     return f" --features {','.join(features)}" if features else ""
 
 
+# What horizon-client's full content-root tests load (mod_content_tests.rs). They take minutes on prepared data, so
+# they are #[ignore]d and run here only when one of these changes.
+CONTENT_ROOT = ("crates/horizon-client/src/mod_content", "crates/horizon-client/src/assets.rs",
+                "crates/horizon-client/src/blocks.rs", "crates/horizon-client/src/items.rs", "crates/horizon-items/",
+                "crates/horizon-mods/", "crates/horizon-assets/")
+CONTENT_ROOT_TESTS = "cargo test --locked -p horizon-client --features horizon-client/mods --lib mod_content::tests:: -- --ignored"
+
+
 def plan(args, base, changed, crates_of, libraries, dependencies):
     """The checks for these changed files, in the order they run."""
     rust = any(workspace_rust(path) for path in changed)
@@ -323,6 +331,9 @@ def plan(args, base, changed, crates_of, libraries, dependencies):
              skip=test_skip, summary=tests_passed),
         Step("doc tests", f"cargo test --locked {doc_selection} --doc",
              skip=test_skip or (None if doc_crates else "no library touched"), summary=tests_passed),
+        Step("content root tests", CONTENT_ROOT_TESTS, summary=tests_passed,
+             skip=None if crates is None or any(p.startswith(CONTENT_ROOT) for p in changed)
+             else "content root untouched"),
         Step("tokens.css up to date", "cargo test --locked -p horizon-theme --lib tokens_css_is_up_to_date",
              skip=None if any(p.startswith(("crates/horizon-theme/", "xtask/")) for p in changed)
              else "theme untouched"),