Auto merge of #15584 - nox:plugin, r=jdm

Move script lints to script_plugins

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1 files changed, 53 insertions, 0 deletions

diff --git a/components/script_plugins/ban.rs b/components/script_plugins/ban.rs
new file mode 100644
index 00000000000..4a4e71c08cc
--- /dev/null
+++ b/components/script_plugins/ban.rs
@@ -0,0 +1,53 @@
+/* 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 http://mozilla.org/MPL/2.0/. */
+
+use rustc::lint::{EarlyContext, LintPass, LintArray, EarlyLintPass, LintContext};
+use syntax::ast::Ty;
+use utils::match_ty_unwrap;
+
+declare_lint!(BANNED_TYPE, Deny,
+              "Ban various unsafe type combinations");
+
+/// Lint for banning various unsafe types
+///
+/// Banned types:
+///
+/// - `Cell<JSVal>`
+/// - `Cell<JS<T>>`
+pub struct BanPass;
+
+impl LintPass for BanPass {
+    fn get_lints(&self) -> LintArray {
+        lint_array!(BANNED_TYPE)
+    }
+}
+
+impl EarlyLintPass for BanPass {
+    fn check_ty(&mut self, cx: &EarlyContext, ty: &Ty) {
+        if match_ty_unwrap(ty, &["std", "cell", "Cell"])
+            .and_then(|t| t.get(0))
+            .and_then(|t| match_ty_unwrap(&**t, &["dom", "bindings", "js", "JS"]))
+            .is_some() {
+            cx.span_lint(BANNED_TYPE, ty.span, "Banned type Cell<JS<T>> detected. Use MutJS<JS<T>> instead")
+        }
+        if match_ty_unwrap(ty, &["std", "cell", "Cell"])
+            .and_then(|t| t.get(0))
+            .and_then(|t| match_ty_unwrap(&**t, &["js", "jsval", "JSVal"]))
+            .is_some() {
+            cx.span_lint(BANNED_TYPE, ty.span, "Banned type Cell<JSVal> detected. Use MutJS<JSVal> instead")
+        }
+        if match_ty_unwrap(ty, &["dom", "bindings", "cell", "DOMRefCell"])
+            .and_then(|t| t.get(0))
+            .and_then(|t| match_ty_unwrap(&**t, &["dom", "bindings", "js", "JS"]))
+            .is_some() {
+            cx.span_lint(BANNED_TYPE, ty.span, "Banned type DOMRefCell<JS<T>> detected. Use MutJS<JS<T>> instead")
+        }
+        if match_ty_unwrap(ty, &["dom", "bindings", "cell", "DOMRefCell"])
+            .and_then(|t| t.get(0))
+            .and_then(|t| match_ty_unwrap(&**t, &["js", "jsapi", "Heap"]))
+            .is_some() {
+            cx.span_lint(BANNED_TYPE, ty.span, "Banned type DOMRefCell<Heap<T>> detected. Use Heap<T> directly instead")
+        }
+    }
+}