From 8d8b85158b76c14a4d6e586178bb82d043c1178f Mon Sep 17 00:00:00 2001
From: DaAlbrecht <dadidi42@gmail.com>
Date: Sun, 24 Nov 2024 16:25:01 +0100
Subject: [PATCH 1/2] feat: duplicated bevy version lint

---
 .../src/lints/duplicate_bevy_dependencies.rs  | 38 +++++++++++++++++++
 bevy_lint/src/lints/mod.rs                    |  3 ++
 2 files changed, 41 insertions(+)
 create mode 100644 bevy_lint/src/lints/duplicate_bevy_dependencies.rs

diff --git a/bevy_lint/src/lints/duplicate_bevy_dependencies.rs b/bevy_lint/src/lints/duplicate_bevy_dependencies.rs
new file mode 100644
index 0000000..54bb6a3
--- /dev/null
+++ b/bevy_lint/src/lints/duplicate_bevy_dependencies.rs
@@ -0,0 +1,38 @@
+//! Checks for multiple versions of `bevy` in the dependencies.
+//!
+//! # Motivation
+//!
+//! When different third party crates use incompatible versions of Bevy, it can lead to confusing
+//! errors and type incompatibilities.
+
+use crate::declare_bevy_lint;
+use clippy_utils::{diagnostics::span_lint, find_crates};
+use rustc_lint::{LateContext, LateLintPass};
+use rustc_session::declare_lint_pass;
+use rustc_span::Symbol;
+
+declare_bevy_lint! {
+    pub DUPLICATE_BEVY_DEPENDENCIES,
+    CORRECTNESS,
+    "duplicate bevy dependencies",
+}
+
+declare_lint_pass! {
+     DuplicateBevyDependencies => [DUPLICATE_BEVY_DEPENDENCIES.lint]
+}
+
+impl<'tcx> LateLintPass<'tcx> for DuplicateBevyDependencies {
+    fn check_crate(&mut self, cx: &LateContext<'tcx>) {
+        let bevy_crates = find_crates(cx.tcx, Symbol::intern("bevy"));
+
+        if bevy_crates.len() > 1 {
+            let span = cx.tcx.def_span(bevy_crates[1].def_id());
+            span_lint(
+                cx,
+                DUPLICATE_BEVY_DEPENDENCIES.lint,
+                span,
+                "Multiple versions of `bevy` found",
+            );
+        }
+    }
+}
diff --git a/bevy_lint/src/lints/mod.rs b/bevy_lint/src/lints/mod.rs
index 22b9012..22ed4c9 100644
--- a/bevy_lint/src/lints/mod.rs
+++ b/bevy_lint/src/lints/mod.rs
@@ -7,6 +7,7 @@
 use crate::lint::BevyLint;
 use rustc_lint::{Lint, LintStore};
 
+pub mod duplicate_bevy_dependencies;
 pub mod insert_event_resource;
 pub mod main_return_without_appexit;
 pub mod missing_reflect;
@@ -22,6 +23,7 @@ pub(crate) static LINTS: &[&BevyLint] = &[
     panicking_methods::PANICKING_WORLD_METHODS,
     plugin_not_ending_in_plugin::PLUGIN_NOT_ENDING_IN_PLUGIN,
     zst_query::ZST_QUERY,
+    duplicate_bevy_dependencies::DUPLICATE_BEVY_DEPENDENCIES,
 ];
 
 pub(crate) fn register_lints(store: &mut LintStore) {
@@ -36,4 +38,5 @@ pub(crate) fn register_passes(store: &mut LintStore) {
     store.register_late_pass(|_| Box::new(panicking_methods::PanickingMethods));
     store.register_late_pass(|_| Box::new(plugin_not_ending_in_plugin::PluginNotEndingInPlugin));
     store.register_late_pass(|_| Box::new(zst_query::ZstQuery));
+    store.register_late_pass(|_| Box::new(duplicate_bevy_dependencies::DuplicateBevyDependencies));
 }

From 02c9e73ed8903e24ae1bbf297e864c86b6cd10f4 Mon Sep 17 00:00:00 2001
From: DaAlbrecht <dadidi42@gmail.com>
Date: Sun, 1 Dec 2024 16:54:32 +0100
Subject: [PATCH 2/2] feat: cache 'bevy' symbol

---
 .../src/lints/duplicate_bevy_dependencies.rs  | 20 +++++++++++++++----
 bevy_lint/src/lints/mod.rs                    |  4 +++-
 2 files changed, 19 insertions(+), 5 deletions(-)

diff --git a/bevy_lint/src/lints/duplicate_bevy_dependencies.rs b/bevy_lint/src/lints/duplicate_bevy_dependencies.rs
index 54bb6a3..d66ed3b 100644
--- a/bevy_lint/src/lints/duplicate_bevy_dependencies.rs
+++ b/bevy_lint/src/lints/duplicate_bevy_dependencies.rs
@@ -6,9 +6,9 @@
 //! errors and type incompatibilities.
 
 use crate::declare_bevy_lint;
-use clippy_utils::{diagnostics::span_lint, find_crates};
+use clippy_utils::{diagnostics::span_lint, find_crates, sym};
 use rustc_lint::{LateContext, LateLintPass};
-use rustc_session::declare_lint_pass;
+use rustc_session::impl_lint_pass;
 use rustc_span::Symbol;
 
 declare_bevy_lint! {
@@ -17,13 +17,25 @@ declare_bevy_lint! {
     "duplicate bevy dependencies",
 }
 
-declare_lint_pass! {
+pub(crate) struct DuplicateBevyDependencies {
+    bevy_symbol: Symbol,
+}
+
+impl Default for DuplicateBevyDependencies {
+    fn default() -> Self {
+        Self {
+            bevy_symbol: sym!(bevy),
+        }
+    }
+}
+
+impl_lint_pass! {
      DuplicateBevyDependencies => [DUPLICATE_BEVY_DEPENDENCIES.lint]
 }
 
 impl<'tcx> LateLintPass<'tcx> for DuplicateBevyDependencies {
     fn check_crate(&mut self, cx: &LateContext<'tcx>) {
-        let bevy_crates = find_crates(cx.tcx, Symbol::intern("bevy"));
+        let bevy_crates = find_crates(cx.tcx, self.bevy_symbol);
 
         if bevy_crates.len() > 1 {
             let span = cx.tcx.def_span(bevy_crates[1].def_id());
diff --git a/bevy_lint/src/lints/mod.rs b/bevy_lint/src/lints/mod.rs
index 22ed4c9..4af1153 100644
--- a/bevy_lint/src/lints/mod.rs
+++ b/bevy_lint/src/lints/mod.rs
@@ -38,5 +38,7 @@ pub(crate) fn register_passes(store: &mut LintStore) {
     store.register_late_pass(|_| Box::new(panicking_methods::PanickingMethods));
     store.register_late_pass(|_| Box::new(plugin_not_ending_in_plugin::PluginNotEndingInPlugin));
     store.register_late_pass(|_| Box::new(zst_query::ZstQuery));
-    store.register_late_pass(|_| Box::new(duplicate_bevy_dependencies::DuplicateBevyDependencies));
+    store.register_late_pass(|_| {
+        Box::new(duplicate_bevy_dependencies::DuplicateBevyDependencies::default())
+    });
 }