Replace script_plugins with a clippy like rustc driver (named crown) (#30508)

* Remove script_plugins

* Use crown instead of script_plugins

* crown_is_not_used

* Use crown in command base

* bootstrap crown

* tidy happy

* disable sccache

* Bring crown in tree

* Install crown from tree

* fix windows ci

* fix warning

* fix mac

libscript_plugins.dylib is not available anymore

* Update components/script/lib.rs

Co-authored-by: Martin Robinson <mrobinson@igalia.com>

* Update for nightly-2023-03-18

Mostly just based off https://github.com/servo/servo/pull/30630

* Always install crown

it's slow only when there is new version

* Run crown test with `mach test-unit`

* Small fixups; better trace_in_no_trace tests

* Better doc

* crown in config.toml

* Fix tidy for real

* no sccache on rustc_wrapper

* document rustc overrides

* fixup of compiletest

* Make a few minor comment adjustments

* Fix a typo in python/servo/platform/base.py

Co-authored-by: Samson <16504129+sagudev@users.noreply.github.com>

* Proper test types

* Ignore tidy on crown/tests

---------

Co-authored-by: Martin Robinson <mrobinson@igalia.com>

support/crown/tests/compile-fail/trace_in_no_trace_composable_works.rs

@@ -0,0 +1,25 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
+// compile-flags: --error-format=human
+/// Mock `JSTraceable`
+pub trait JSTraceable {}
+
+struct TraceableStruct;
+impl JSTraceable for TraceableStruct {}
+
+struct NotTraceableStruct;
+
+// `must_not_have_traceable(1)` indicates that the second generic argument should
+// not be traceable and this test verifies that this lint passes enforces this.
+#[crown::trace_in_no_trace_lint::must_not_have_traceable(1)]
+struct NoTraceComposable<Traceable, NoTraceable> {
+    t: Traceable,
+    n: NoTraceable,
+}
+
+// The lint should fail because TraceableStruct is traceable
+struct Foo(NoTraceComposable<TraceableStruct, TraceableStruct>);
+//~^ ERROR: must_not_have_traceable marked wrapper must not have jsmanaged inside on 1-th position. Consider removing the wrapper.
+
+fn main() {}

support/crown/tests/compile-fail/trace_in_no_trace_works.rs

@@ -0,0 +1,19 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
+
+/// Mock `JSTraceable`
+pub trait JSTraceable {}
+
+struct TraceableStruct;
+impl JSTraceable for TraceableStruct {}
+
+struct NotTraceableStruct;
+
+#[crown::trace_in_no_trace_lint::must_not_have_traceable]
+struct NoTrace<T>(T);
+
+struct Foo(NoTrace<TraceableStruct>);
+//~^ ERROR: must_not_have_traceable marked wrapper must not have jsmanaged inside on 0-th position. Consider removing the wrapper.
+
+fn main() {}

support/crown/tests/compile-fail/unrooted_must_root_parameter.rs

@@ -0,0 +1,10 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
+
+#[crown::unrooted_must_root_lint::must_root]
+struct Foo(i32);
+
+fn foo1(_: Foo) {} //~ ERROR: Type must be rooted
+
+fn main() {}

support/crown/tests/compile-fail/unrooted_must_root_return_type.rs

@@ -0,0 +1,13 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
+
+#[crown::unrooted_must_root_lint::must_root]
+struct Foo(i32);
+
+fn foo2() -> Foo {
+    //~^ ERROR: Type must be rooted
+    unimplemented!()
+}
+
+fn main() {}

support/crown/tests/compile-fail/unrooted_must_root_struct_field.rs

@@ -0,0 +1,10 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
+
+#[crown::unrooted_must_root_lint::must_root]
+struct Foo(i32);
+struct Bar(Foo);
+//~^ ERROR: Type must be rooted, use #[crown::unrooted_must_root_lint::must_root] on the struct definition to propagate
+
+fn main() {}

support/crown/tests/compile_test.rs

@@ -0,0 +1,52 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
+
+use std::env;
+use std::path::PathBuf;
+
+use compiletest_rs as compiletest;
+use once_cell::sync::Lazy;
+
+static PROFILE_PATH: Lazy<PathBuf> = Lazy::new(|| {
+    let current_exe_path = env::current_exe().unwrap();
+    let deps_path = current_exe_path.parent().unwrap();
+    let profile_path = deps_path.parent().unwrap();
+    profile_path.into()
+});
+
+fn run_mode(mode: &'static str, bless: bool) {
+    let mut config = compiletest::Config {
+        bless,
+        edition: Some("2021".into()),
+        ..Default::default()
+    }
+    .tempdir();
+
+    let cfg_mode = mode.parse().expect("Invalid mode");
+    config.mode = cfg_mode;
+    config.src_base = PathBuf::from("tests").join(mode);
+    config.rustc_path = PROFILE_PATH.join("crown");
+    config.target_rustcflags = Some(format!(
+        "-L {} -L {} -Zcrate-attr=feature(register_tool) -Zcrate-attr=register_tool(crown)",
+        PROFILE_PATH.display(),
+        PROFILE_PATH.join("deps").display()
+    ));
+    // Does not work reliably: https://github.com/servo/servo/pull/30508#issuecomment-1834542203
+    //config.link_deps();
+    config.clean_rmeta();
+    config.strict_headers = true;
+
+    compiletest::run_tests(&config);
+}
+
+#[test]
+fn compile_test() {
+    let bless = env::var("BLESS").map_or(false, |x| !x.trim().is_empty());
+    run_mode("compile-fail", bless);
+    run_mode("run-pass", bless);
+    // UI test fails on windows
+    if !cfg!(windows) {
+        run_mode("ui", bless);
+    }
+}

support/crown/tests/run-pass/trace_in_no_trace_composable.rs

@@ -0,0 +1,24 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
+
+/// Mock `JSTraceable`
+pub trait JSTraceable {}
+
+struct TraceableStruct;
+impl JSTraceable for TraceableStruct {}
+
+struct NotTraceableStruct;
+
+// `must_not_have_traceable(1)` indicates that the second generic argument should
+// not be traceable and this test verifies that this lint passes.
+#[crown::trace_in_no_trace_lint::must_not_have_traceable(1)]
+struct NoTraceComposable<Traceable, NoTraceable> {
+    t: Traceable,
+    n: NoTraceable,
+}
+
+// this is ok: TraceableStruct is traceable
+struct Foo(NoTraceComposable<TraceableStruct, NotTraceableStruct>);
+
+fn main() {}

support/crown/tests/run-pass/trace_in_no_trace_ok.rs

@@ -0,0 +1,18 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
+
+/// Mock `JSTraceable`
+pub trait JSTraceable {}
+
+struct TraceableStruct;
+impl JSTraceable for TraceableStruct {}
+
+struct NotTraceableStruct;
+
+#[crown::trace_in_no_trace_lint::must_not_have_traceable]
+struct NoTrace<T>(T);
+
+struct Foo(NoTrace<NotTraceableStruct>);
+
+fn main() {}

support/crown/tests/run-pass/unrooted_must_root_ok.rs

@@ -0,0 +1,15 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
+// compile-flags: --error-format=human
+#[crown::unrooted_must_root_lint::must_root]
+struct Foo(i32);
+#[crown::unrooted_must_root_lint::must_root]
+struct Bar(Foo);
+
+fn foo1(_: &Foo) {}
+fn foo2(_: &()) -> &Foo {
+    unimplemented!()
+}
+
+fn main() {}

support/crown/tests/ui/trace_in_no_trace_primitive.rs

@@ -0,0 +1,17 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
+
+/// Mock `JSTraceable`
+pub trait JSTraceable {}
+impl JSTraceable for i32 {}
+
+// second generic argument must not be traceable
+#[crown::trace_in_no_trace_lint::must_not_have_traceable(0)]
+struct NoTrace<NoTraceable> {
+    n: NoTraceable,
+}
+
+struct Foo(NoTrace<i32>);
+
+fn main() {}

support/crown/tests/ui/trace_in_no_trace_primitive.stderr

@@ -0,0 +1,10 @@
+warning: must_not_have_traceable marked wrapper is not needed for types that implements empty Traceable (like primitive types). Consider removing the wrapper.
+  --> $DIR/trace_in_no_trace_primitive.rs:15:12
+   |
+15 | struct Foo(NoTrace<i32>);
+   |            ^^^^^^^^^^^^
+   |
+   = note: `#[warn(crown::empty_trace_in_no_trace)]` on by default
+
+warning: 1 warning emitted
+