Fix returned NumberLiteral's kind in StringLiteral#to_i

spec/compiler/macro/macro_methods_spec.cr

@@ -637,6 +637,18 @@ module Crystal
         assert_macro %({{"1234".to_i(16)}}), %(4660)
       end
 
+      it "adds correct number kind on to_i (#16467)" do
+        assert_macro %({{"0".to_i.kind}}), %(:i32)
+        assert_macro %({{"2147483647".to_i.kind}}), %(:i32)
+        assert_macro %({{"2147483648".to_i.kind}}), %(:i64)
+        assert_macro %({{"123456789012345".to_i.kind}}), %(:i64)
+        assert_macro %({{"7fffffffffffffff".to_i(16).kind}}), %(:i64)
+        assert_macro %({{"-2147483648".to_i.kind}}), %(:i32)
+        assert_macro %({{"-2147483649".to_i.kind}}), %(:i64)
+        assert_macro %({{"-123456789012345".to_i.kind}}), %(:i64)
+        assert_macro %({{"-8000000000000000".to_i(16).kind}}), %(:i64)
+      end
+
       it "executes string includes? char (true)" do
         assert_macro %({{"spice".includes?('s')}}), %(true)
         assert_macro %({{"spice".includes?('p')}}), %(true)

src/compiler/crystal/macros.cr

@@ -102,8 +102,12 @@ private macro def_string_methods(klass)
   def titleize : {{klass}}
   end
 
-  # Similar to `String#to_i`.
-  def to_i(base = 10)
+  # Similar to `String#to_i64`.
+  #
+  # The returned `NumberLiteral` has the `:i32` kind if it fits into `Int32`'s
+  # range, and the `:i64` kind otherwise. This matches the behavior of
+  # suffix-less number literals in Crystal.
+  def to_i(base : NumberLiteral = 10) : NumberLiteral
   end
 
   # Returns an expression that evaluates to a slice literal containing the

src/compiler/crystal/macros/methods.cr

@@ -900,7 +900,11 @@ module Crystal
         end
 
         if value
-          NumberLiteral.new(value.to_s, :i32)
+          if value.in?(Int32::MIN..Int32::MAX)
+            NumberLiteral.new(value.to_s, :i32)
+          else
+            NumberLiteral.new(value.to_s, :i64)
+          end
         else
           raise "StringLiteral#to_i: #{@value} is not an integer"
         end