add config item for hover display

crates/hir-ty/src/display.rs

@@ -62,7 +62,7 @@ pub struct HirFormatter<'a> {
     fmt: &'a mut dyn HirWrite,
     buf: String,
     curr_size: usize,
-    pub(crate) max_size: Option<usize>,
+    pub max_size: Option<usize>,
     omit_verbose_types: bool,
     closure_style: ClosureStyle,
     display_target: DisplayTarget,

crates/hir/src/display.rs

@@ -593,12 +593,14 @@ impl HirDisplay for Trait {
         write_generic_params(def_id, f)?;
         write_where_clause(def_id, f)?;
 
+        let mut display_size = 0;
+        let max_display_size = f.max_size.unwrap_or(7);
         let assoc_items = self.items(f.db);
         if assoc_items.is_empty() {
             f.write_str(" {}")?;
         } else {
             f.write_str(" {\n")?;
-            for item in assoc_items {
+            for (index, item) in assoc_items.iter().enumerate() {
                 f.write_str("    ")?;
                 match item {
                     AssocItem::Function(func) => {
@@ -612,6 +614,11 @@ impl HirDisplay for Trait {
                     }
                 };
                 f.write_str(",\n")?;
+                display_size += 1;
+                if display_size == max_display_size && index != assoc_items.len() - 1{
+                    f.write_str("    ...\n")?;
+                    break;
+                }
             }
             f.write_str("}")?;
         }

crates/ide-db/src/defs.rs

@@ -213,7 +213,7 @@ impl Definition {
         })
     }
 
-    pub fn label(&self, db: &RootDatabase) -> String {
+    pub fn label(&self, db: &RootDatabase, max_size: Option<usize>) -> String {
         match *self {
             Definition::Macro(it) => it.display(db).to_string(),
             Definition::Field(it) => it.display(db).to_string(),
@@ -224,7 +224,7 @@ impl Definition {
             Definition::Variant(it) => it.display(db).to_string(),
             Definition::Const(it) => it.display(db).to_string(),
             Definition::Static(it) => it.display(db).to_string(),
-            Definition::Trait(it) => it.display(db).to_string(),
+            Definition::Trait(it) => it.display_truncated(db, max_size).to_string(),
             Definition::TraitAlias(it) => it.display(db).to_string(),
             Definition::TypeAlias(it) => it.display(db).to_string(),
             Definition::BuiltinType(it) => it.name().display(db).to_string(),

crates/ide/src/hover.rs

@@ -32,6 +32,7 @@ pub struct HoverConfig {
     pub documentation: bool,
     pub keywords: bool,
     pub format: HoverDocFormat,
+    pub trait_item_display_on_hover: Option<usize>,
 }
 
 #[derive(Copy, Clone, Debug, PartialEq, Eq)]

crates/ide/src/hover/render.rs

@@ -406,7 +406,7 @@ pub(super) fn definition(
     config: &HoverConfig,
 ) -> Markup {
     let mod_path = definition_mod_path(db, &def);
-    let label = def.label(db);
+    let label = def.label(db, config.trait_item_display_on_hover);
     let docs = def.docs(db, famous_defs);
     let value = (|| match def {
         Definition::Variant(it) => {

crates/ide/src/hover/tests.rs

@@ -17,6 +17,7 @@ const HOVER_BASE_CONFIG: HoverConfig = HoverConfig {
     documentation: true,
     format: HoverDocFormat::Markdown,
     keywords: true,
+    trait_item_display_on_hover: Some(7),
 };
 
 fn check_hover_no_result(ra_fixture: &str) {

crates/ide/src/static_index.rs

@@ -166,6 +166,7 @@ impl StaticIndex<'_> {
             documentation: true,
             keywords: true,
             format: crate::HoverDocFormat::Markdown,
+            trait_item_display_on_hover: Some(7)
         };
         let tokens = tokens.filter(|token| {
             matches!(
@@ -196,7 +197,7 @@ impl StaticIndex<'_> {
                     enclosing_moniker: current_crate
                         .zip(def.enclosing_definition(self.db))
                         .and_then(|(cc, enclosing_def)| def_to_moniker(self.db, enclosing_def, cc)),
-                    signature: Some(def.label(self.db)),
+                    signature: Some(def.label(self.db, hover_config.trait_item_display_on_hover)),
                     kind: def_to_kind(self.db, def),
                 });
                 self.def_map.insert(def, it);

crates/rust-analyzer/src/config.rs

@@ -511,7 +511,6 @@ config_data! {
         /// Exclude tests from find-all-references.
         references_excludeTests: bool = "false",
 
-
         /// Command to be executed instead of 'cargo' for runnables.
         runnables_command: Option<String> = "null",
         /// Additional arguments to be passed to cargo for runnables such as
@@ -591,6 +590,9 @@ config_data! {
         /// Show documentation.
         signatureInfo_documentation_enable: bool                       = "true",
 
+        /// How many trait item display on hover.
+        trait_item_display_on_hover: Option<usize> = "7",
+
         /// Whether to insert closing angle brackets when typing an opening angle bracket of a generic argument list.
         typing_autoClosingAngleBrackets_enable: bool = "false",
 
@@ -1683,6 +1685,7 @@ impl Config {
                 }
             },
             keywords: self.data.hover_documentation_keywords_enable,
+            trait_item_display_on_hover: self.data.trait_item_display_on_hover,
         }
     }
 

docs/user/generated_config.adoc

@@ -927,6 +927,11 @@ Show full signature of the callable. Only shows parameters if disabled.
 --
 Show documentation.
 --
+[[rust-analyzer.trait.item.display.on.hover]]rust-analyzer.trait.item.display.on.hover (default: `7`)::
++
+--
+How many trait item display on hover.
+--
 [[rust-analyzer.typing.autoClosingAngleBrackets.enable]]rust-analyzer.typing.autoClosingAngleBrackets.enable (default: `false`)::
 +
 --

editors/code/package.json

@@ -1648,6 +1648,15 @@
                     "default": true,
                     "type": "boolean"
                 },
+                "rust-analyzer.trait.item.display.on.hover": {
+                    "markdownDescription": "How many trait item display on hover.",
+                    "default": 7,
+                    "type": [
+                        "null",
+                        "integer"
+                    ],
+                    "minimum": 0
+                },
                 "rust-analyzer.typing.autoClosingAngleBrackets.enable": {
                     "markdownDescription": "Whether to insert closing angle brackets when typing an opening angle bracket of a generic argument list.",
                     "default": false,