expload the test cases for Int

... with different kinds of ways to initialize a scalar varible with
"number" inside.

t/101_issues/Int.t

@@ -2,16 +2,37 @@
 use strict;
 use warnings;
 use Test::More;
+use Devel::Peek qw<Dump>;
 use Mouse::Util::TypeConstraints;
 
 my $Int    = find_type_constraint 'Int';
 
-my $num = 3.14;
+subtest "Non-Int from numerical literal: my \$num = 3.14", sub {
+    my $num = 3.14;
+    ok !$Int->check($num), "\$num is not Int";
+    { no warnings; int($num) };
+    ok !$Int->check($num), "\$num is still not Int";
+};
 
-ok !$Int->check($num), "\$num (== 3.14) is not Int";
+subtest "Non-Int from string literal: my \$num = \"3.14\"", sub {
+    my $num = "3.14";
+    ok !$Int->check($num), "\$num is not Int";
+    { no warnings; int($num) };
+    ok !$Int->check($num), "\$num is still not Int";
+};
 
-{ no warnings; int($num) };
+subtest "Int from string literal: my \$num = \"3\"", sub {
+    my $num = "3";
+    ok $Int->check($num), "\$num is Int";
+    { no warnings; int($num) };
+    ok $Int->check($num), "\$num is still Int";
+};
 
-ok !$Int->check($num), "\$num (== 3.14) is still not Int";
+subtest "Int from integer literal: my \$num = 3", sub {
+    my $num = 3;
+    ok $Int->check($num), "\$num is Int";
+    { no warnings; int($num) };
+    ok $Int->check($num), "\$num is still Int";
+};
 
 done_testing;