Provide an option to hide deprecated items from completion

Author: ChayimFriedman2

crates/rust-analyzer/src/config.rs

@@ -512,6 +512,8 @@ config_data! {
         completion_termSearch_enable: bool = false,
         /// Term search fuel in "units of work" for autocompletion (Defaults to 1000).
         completion_termSearch_fuel: usize = 1000,
+        /// Whether to omit deprecated items from autocompletion. By default they are marked as deprecated but not hidden.
+        completions_hideDeprecated: bool = false,
 
         /// Controls file watching implementation.
         files_watcher: FilesWatcherDef = FilesWatcherDef::Client,
@@ -1435,6 +1437,10 @@ impl Config {
         }
     }
 
+    pub fn completion_hide_deprecated(&self) -> bool {
+        *self.completions_hideDeprecated()
+    }
+
     pub fn detached_files(&self) -> &Vec<AbsPathBuf> {
         // FIXME @alibektas : This is the only config that is confusing. If it's a proper configuration
         // why is it not among the others? If it's client only which I doubt it is current state should be alright

crates/rust-analyzer/src/lsp/to_proto.rs

@@ -228,8 +228,12 @@ pub(crate) fn completion_items(
     line_index: &LineIndex,
     version: Option<i32>,
     tdpp: lsp_types::TextDocumentPositionParams,
-    items: Vec<CompletionItem>,
+    mut items: Vec<CompletionItem>,
 ) -> Vec<lsp_types::CompletionItem> {
+    if config.completion_hide_deprecated() {
+        items.retain(|item| !item.deprecated);
+    }
+
     let max_relevance = items.iter().map(|it| it.relevance.score()).max().unwrap_or_default();
     let mut res = Vec::with_capacity(items.len());
     for item in items {

docs/user/generated_config.adoc

@@ -358,6 +358,11 @@ Whether to enable term search based snippets like `Some(foo.bar().baz())`.
 --
 Term search fuel in "units of work" for autocompletion (Defaults to 1000).
 --
+[[rust-analyzer.completions.hideDeprecated]]rust-analyzer.completions.hideDeprecated (default: `false`)::
++
+--
+Whether to omit deprecated items from autocompletion. By default they are marked as deprecated but not hidden.
+--
 [[rust-analyzer.diagnostics.disabled]]rust-analyzer.diagnostics.disabled (default: `[]`)::
 +
 --

editors/code/package.json

@@ -1182,6 +1182,16 @@
                     }
                 }
             },
+            {
+                "title": "completions",
+                "properties": {
+                    "rust-analyzer.completions.hideDeprecated": {
+                        "markdownDescription": "Whether to omit deprecated items from autocompletion. By default they are marked as deprecated but not hidden.",
+                        "default": false,
+                        "type": "boolean"
+                    }
+                }
+            },
             {
                 "title": "diagnostics",
                 "properties": {