From 798c963875c685179b431021ef2a08542739f14d Mon Sep 17 00:00:00 2001
From: Chayim Refael Friedman <chayimfr@gmail.com>
Date: Mon, 16 Sep 2024 01:30:18 +0300
Subject: [PATCH] Fix printing of constants greater than `i128::MAX`

---
 crates/hir/src/lib.rs         | 12 +++++++++---
 crates/ide/src/hover/tests.rs | 18 ++++++++++++++++++
 2 files changed, 27 insertions(+), 3 deletions(-)

diff --git a/crates/hir/src/lib.rs b/crates/hir/src/lib.rs
index e3bd75620833..176c059bf623 100644
--- a/crates/hir/src/lib.rs
+++ b/crates/hir/src/lib.rs
@@ -80,7 +80,7 @@ use nameres::diagnostics::DefDiagnosticKind;
 use rustc_hash::FxHashSet;
 use smallvec::SmallVec;
 use span::{Edition, EditionedFileId, FileId, MacroCallId, SyntaxContextId};
-use stdx::{impl_from, never};
+use stdx::{format_to, impl_from, never};
 use syntax::{
     ast::{self, HasAttrs as _, HasGenericParams, HasName},
     format_smolstr, AstNode, AstPtr, SmolStr, SyntaxNode, SyntaxNodePtr, TextRange, ToSmolStr, T,
@@ -2578,10 +2578,16 @@ impl Const {
                         let value = u128::from_le_bytes(mir::pad16(b, false));
                         let value_signed =
                             i128::from_le_bytes(mir::pad16(b, matches!(s, Scalar::Int(_))));
+                        let mut result = if let Scalar::Int(_) = s {
+                            value_signed.to_string()
+                        } else {
+                            value.to_string()
+                        };
                         if value >= 10 {
-                            return Ok(format!("{value_signed} ({value:#X})"));
+                            format_to!(result, " ({value:#X})");
+                            return Ok(result);
                         } else {
-                            return Ok(format!("{value_signed}"));
+                            return Ok(result);
                         }
                     }
                 }
diff --git a/crates/ide/src/hover/tests.rs b/crates/ide/src/hover/tests.rs
index f2e5d24fcc68..8805ead818a5 100644
--- a/crates/ide/src/hover/tests.rs
+++ b/crates/ide/src/hover/tests.rs
@@ -1496,6 +1496,24 @@ const foo$0: u32 = {
     );
 }
 
+#[test]
+fn hover_unsigned_max_const() {
+    check(
+        r#"const $0A: u128 = -1_i128 as u128;"#,
+        expect![[r#"
+            *A*
+
+            ```rust
+            test
+            ```
+
+            ```rust
+            const A: u128 = 340282366920938463463374607431768211455 (0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF)
+            ```
+        "#]],
+    );
+}
+
 #[test]
 fn hover_eval_complex_constants() {
     check(