ANN: annotate unsafe module and module declarations

Author: Undin

src/main/kotlin/org/rust/ide/annotator/RsSyntaxErrorsAnnotator.kt

@@ -38,6 +38,8 @@ class RsSyntaxErrorsAnnotator : AnnotatorBase() {
                     is RsStructItem -> checkStructItem(holder, element)
                     is RsTypeAlias -> checkTypeAlias(holder, element)
                     is RsConstant -> checkConstant(holder, element)
+                    is RsModItem -> checkModItem(holder, element)
+                    is RsModDeclItem -> checkModDeclItem(holder, element)
                 }
             }
             is RsMacro -> checkMacro(holder, element)
@@ -320,6 +322,20 @@ private fun checkExternAbi(holder: AnnotationHolder, element: RsExternAbi) {
     }
 }
 
+private fun checkModDeclItem(holder: AnnotationHolder, element: RsModDeclItem) {
+    checkUnsafeModule(holder, element.unsafe)
+}
+
+private fun checkModItem(holder: AnnotationHolder, element: RsModItem) {
+    checkUnsafeModule(holder, element.unsafe)
+}
+
+private fun checkUnsafeModule(holder: AnnotationHolder, unsafe: PsiElement?) {
+    if (unsafe != null) {
+        holder.newAnnotation(HighlightSeverity.ERROR, "Module cannot be declared unsafe").range(unsafe).create()
+    }
+}
+
 private enum class TypeKind {
     LIFETIME,
     TYPE,

src/test/kotlin/org/rust/ide/annotator/RsSyntaxErrorsAnnotatorTest.kt

@@ -407,4 +407,16 @@ class RsSyntaxErrorsAnnotatorTest : RsAnnotatorTestBase(RsSyntaxErrorsAnnotator:
         type ExternFnWithRawAbi = extern r"system" fn();
         type ExternFnWithInvalidAbi = extern <error descr="Non-string ABI literal">true</error> fn();
     """)
+
+    fun `test unsafe module`() = checkErrors("""
+        mod module {}
+        pub mod pub_module {}
+        <error descr="Module cannot be declared unsafe">unsafe</error> mod unsafe_module {}
+        pub <error descr="Module cannot be declared unsafe">unsafe</error> mod unsafe_module {}
+
+        mod mod_delc;
+        pub mod pub_mmod_delc;
+        <error descr="Module cannot be declared unsafe">unsafe</error> mod unsafe_mod_delc;
+        pub <error descr="Module cannot be declared unsafe">unsafe</error> mod unsafe_mod_delc;
+    """)
 }