Porting the fix in aa42c83 to 6.c-errata

The quick overview is that the tests for (over|under)flow and assigning
literals more than max or less than min were incorrect.

S02-types/int-uint.t

@@ -4,9 +4,10 @@ use Test;
 # L<S09/Sized types/Sized low-level types are named most generally by appending the number of bits to a generic low-level type name>
 
 my @inttypes = <1 2 4 8 16 32 64>.map({
-  "int$_","uint$_"
+  |("int$_","uint$_")
 }).grep: {
-    try EVAL "my $_ \$var; \$var.WHAT eq '($_)'"
+    use MONKEY-SEE-NO-EVAL;
+    try EVAL "my $_ \$var = 1; \$var"
 };
 
 # nothing to test, we're done
@@ -16,30 +17,64 @@ unless @inttypes {
     exit;
 }
 
-plan 9 * @inttypes;
+plan 11 * @inttypes;
 
 for @inttypes -> $type {
+    my ($minval,$maxval) = ::($type).Range.int-bounds;
 
-    my $maxval; my $minval;
-    $type ~~ /(\d+)/;
-    my $len = $/[0]; # get the numeric value
-    if $type ~~ /^uint/ {
-        $maxval = 2**$len - 1;
-        $minval = 0;
-    } else { # /^int/
-        $maxval = 2**($len - 1) - 1;
-        $minval = -(2**($len - 1));
+    if $type eq "uint64" {
+        #?rakudo todo 'getting -1 instead of 18446744073709551615'
+        is EVAL("my $type \$var = $maxval; \$var"), $maxval,
+          "$type can be $maxval";
+    } else {
+        is EVAL("my $type \$var = $maxval; \$var"), $maxval,
+          "$type can be $maxval";
     }
 
-    is(EVAL("my $type \$var = $maxval"), $maxval, "$type can be $maxval");
-    is(EVAL("my $type \$var = $minval"), $minval, "$type can be $minval");
+    is EVAL("my $type \$var = $minval; \$var"), $minval,
+      "$type can be $minval";
 
-    throws-like { EVAL "my $type \$var = {$maxval+1}" },
-      Exception,
-      "$type cannot be {$maxval+1}";
+    if $type eq "uint64" {
+        is EVAL("my $type \$var = $maxval; \$var++; \$var"), $minval,
+          "$type overflows to $minval";
+    } elsif $type eq "int64" {
+        is EVAL("my $type \$var = $maxval; \$var++; \$var"), $minval,
+          "$type overflows to $minval";
+    } else {
+        #?rakudo.jvm todo 'max overflow to min'
+        is EVAL("my $type \$var = $maxval; \$var++; \$var"), $minval,
+          "$type overflows to $minval";
+    }
+
+    if $type eq "uint64" {
+        #?rakudo todo 'getting -1 instead of 0'
+        is EVAL("my $type \$var = $minval; \$var--; \$var"), $maxval,
+          "$type underflows to $maxval";
+    } elsif $type eq "int64" {
+        is EVAL("my $type \$var = $minval; \$var--; \$var"), $maxval,
+          "$type underflows to $maxval";
+    } else {
+        #?rakudo.jvm todo 'underflow to max'
+        is EVAL("my $type \$var = $minval; \$var--; \$var"), $maxval,
+          "$type underflows to $maxval";
+    }
+
+    if $type eq "uint64" {
+        #?rakudo.jvm todo 'setting to more than max'
+        throws-like { EVAL "my $type \$var = {$maxval+1}" },
+          Exception,
+          "setting $type to more than $maxval throws";
+    } else {
+        #?rakudo todo 'setting more than max throws'
+        throws-like { EVAL "my $type \$var = {$maxval+1}" },
+          Exception,
+          "setting $type to more than $maxval throws";
+    }
+    #?rakudo todo 'setting less than min throws'
     throws-like { EVAL "my $type \$var = {$minval-1}" },
       Exception,
-      "$type cannot be {$minval-1}";
+      "setting $type to less than $minval throws";
+
     throws-like { EVAL "my $type \$var = 'foo'" },
       Exception,
       "$type cannot be a string";