Fix for issue 4725 - dedup Item imports_granularity

Author: davidBar-On

src/formatting/imports.rs

@@ -183,7 +183,7 @@ pub(crate) fn merge_use_trees(use_trees: Vec<UseTree>, merge_by: SharedPrefix) -
 }
 
 pub(crate) fn flatten_use_trees(use_trees: Vec<UseTree>) -> Vec<UseTree> {
-    use_trees
+    let mut ut: Vec<UseTree> = use_trees
         .into_iter()
         .flat_map(UseTree::flatten)
         .map(|mut tree| {
@@ -197,7 +197,9 @@ pub(crate) fn flatten_use_trees(use_trees: Vec<UseTree>) -> Vec<UseTree> {
             }
             tree
         })
-        .collect()
+        .collect();
+    ut.dedup();
+    return ut;
 }
 
 impl fmt::Debug for UseTree {

src/formatting/reorder.rs

@@ -243,7 +243,15 @@ fn rewrite_reorderable_or_regroupable_items(
             };
 
             if context.config.reorder_imports() {
-                regrouped_items.iter_mut().for_each(|items| items.sort())
+                regrouped_items.iter_mut().for_each(|items| {
+                    items.sort();
+                    match context.config.imports_granularity() {
+                        ImportGranularity::Crate
+                        | ImportGranularity::Module
+                        | ImportGranularity::Item => items.dedup(),
+                        ImportGranularity::Preserve => {}
+                    }
+                })
             }
 
             // 4 = "use ", 1 = ";"