From 6f4a6b816717a4fb3033335503dd7c7996b143e0 Mon Sep 17 00:00:00 2001
From: Copilot <198982749+Copilot@users.noreply.github.com>
Date: Thu, 22 Jan 2026 17:00:59 +0800
Subject: [PATCH] [WIP] Refactor to helper proc based on review feedback
 (#25454)
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- [x] Extract bit width check logic (lines 496-513) to a helper
procedure
- [ ] Test the changes to ensure correctness
- [ ] Run final code review

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---
 compiler/lexer.nim | 40 +++++++++++++++++++++++-----------------
 1 file changed, 23 insertions(+), 17 deletions(-)

diff --git a/compiler/lexer.nim b/compiler/lexer.nim
index 1609df4d40..aa06ca2d12 100644
--- a/compiler/lexer.nim
+++ b/compiler/lexer.nim
@@ -316,6 +316,28 @@ proc getNumber(L: var Lexer, result: var Token) =
     L.bufpos = msgPos
     lexMessage(L, msgKind, msg % t.literal)
 
+  proc checkBitWidth(L: var Lexer, base: TNumeralBase, tokType: TokType, 
+                     numDigits: int, startpos: int) =
+    # Check bit width for non-base-10 literals
+    # Warn if the digit count exceeds what can fit in the target type
+    let bitsPerDigit = case base
+      of base2: 1
+      of base8: 3
+      of base16: 4
+      else: raiseAssert "unreachable"
+    let bitWidth = case tokType
+      of tkInt8Lit, tkUInt8Lit: 8
+      of tkInt16Lit, tkUInt16Lit: 16
+      of tkInt32Lit, tkUInt32Lit: 32
+      of tkInt64Lit, tkUIntLit, tkIntLit, tkUInt64Lit: 64
+      else: raiseAssert "unreachable"
+    # Maximum digits = ceil(bitWidth / bitsPerDigit) = (bitWidth + bitsPerDigit - 1) div bitsPerDigit
+    let maxDigits = (bitWidth + bitsPerDigit - 1) div bitsPerDigit
+    if numDigits > maxDigits:
+      lexMessageLitNum(L,
+        "number has " & $numDigits & " digits but type only supports " &
+        $maxDigits & " digits: '$1'", startpos, warnLongLiterals)
+
   var
     xi: BiggestInt
     isBase10 = true
@@ -494,23 +516,7 @@ proc getNumber(L: var Lexer, result: var Token) =
         # Check bit width for non-base-10 literals
         # Warn if the digit count exceeds what can fit in the target type
         if result.base != base10 and result.tokType in {tkIntLit..tkUInt64Lit} and numDigits > 0:
-          let bitsPerDigit = case result.base
-            of base2: 1
-            of base8: 3
-            of base16: 4
-            else: raiseAssert "unreachable"
-          let bitWidth = case result.tokType
-            of tkInt8Lit, tkUInt8Lit: 8
-            of tkInt16Lit, tkUInt16Lit: 16
-            of tkInt32Lit, tkUInt32Lit: 32
-            of tkInt64Lit, tkUIntLit, tkIntLit, tkUInt64Lit: 64
-            else: raiseAssert "unreachable"
-          # Maximum digits = ceil(bitWidth / bitsPerDigit) = (bitWidth + bitsPerDigit - 1) div bitsPerDigit
-          let maxDigits = (bitWidth + bitsPerDigit - 1) div bitsPerDigit
-          if numDigits > maxDigits:
-            lexMessageLitNum(L,
-              "number has " & $numDigits & " digits but type only supports " &
-              $maxDigits & " digits: '$1'", startpos, warnLongLiterals)
+          checkBitWidth(L, result.base, result.tokType, numDigits, startpos)
 
         # Bounds checks. Non decimal literals are allowed to overflow the range of
         # the datatype as long as their pattern don't overflow _bitwise_, hence