2 files changed, 82 insertions(+), 0 deletions(-)

A src/UInt.php
M tests/PrimitivesTest.php

@@ 0,0 1,44 @@
+<?php
+
+namespace BareMess;
+
+class UInt
+{
+    use Mutatable;
+    private int $value = 0;
+
+    public function __construct(& $mess = null)
+    {
+        if ($mess === null){
+            return;
+        }
+        $this->value = 0;
+        for($i = 0; $i < strlen($mess); $i++) {
+            // Least significant bits first
+            $this->value += (ord($mess[$i]) & 0b01111111) << (7 * $i);
+            if(! (ord($mess[$i]) & 0b10000000) ) {
+                $mess = substr($mess, $i + 1);
+                return;
+            }
+        }
+    }
+
+    public function mess()
+    {
+        $mess = '';
+        // The number of bytes should be greater than or equal to the number required,
+        // value < pow(2, 7 * bytes)
+        $bytes = floor(log($this->value + 1, 2) / 7) + 1;
+
+        for ($i = 0; $i < $bytes; $i++) {
+            // BARE encodes integers as little-endian (least significant first),
+            $bits = ($this->value >> ($i * 7)) & 0b01111111;
+            // with the most significant bit being set for all except the last byte.
+            if ($i != $bytes - 1) {
+                $bits = $bits | 0b10000000;
+            }
+            $mess .= chr($bits);
+        }
+        return $mess;
+    }
+}

@@ 6,6 6,7 @@ use BareMess\Bare;
 use BareMess\Example\PublicKey;
 use BareMess\{I8,I16,I32,I64};
 use BareMess\{U8,U16,U32,U64};
+use BareMess\UInt;
 use PHPUnit\Framework\TestCase;
 
 class PrimitivesTest extends TestCase


@@ 87,6 88,43 @@ class PrimitivesTest extends TestCase
         // TODO: Test strings longer than 127 characters
     }
 
+    public function testUInt()
+    {
+        // Various equivalent uints.
+        $mess = "\xC2\x80\x00\xC2\x00\x42";
+        $uint = new UInt($mess);
+        $uint2 = new UInt($mess);
+        $uint3 = new UInt($mess);
+        $this->assertEquals('', $mess);
+        $this->assertEquals(66, $uint->get());
+        $this->assertEquals(66, $uint2->get());
+        $this->assertEquals(66, $uint3->get());
+        $this->assertEquals("\x42", $uint->mess());
+        $this->assertEquals("\x42", $uint2->mess());
+        $this->assertEquals("\x42", $uint3->mess());
+
+        $uint->set(0);
+        $this->assertEquals("\x00", $uint->mess());
+
+        // This is usually equal to PHP_INT_MAX
+        $sixtythreeBitNumber = 0x7FFFFFFFFFFFFFFF;
+        $mess = "\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\x7F";
+        $uint = new UInt($mess);
+        $this->assertEquals("", $mess);
+        $this->assertEquals($sixtythreeBitNumber, $uint->get());
+        $mess = $uint->mess();
+        $uint2 = new UInt($mess);
+        $this->assertEquals('', $mess);
+        $this->assertEquals($sixtythreeBitNumber, $uint2->get());
+
+        // Test round-tripping with mess (since these have multiple representations).
+        $uint->set(pow(2,7*8));
+        $mess = $uint->mess();
+        $uint2 = new UInt($mess);
+        $this->assertEquals("", $mess);
+        $this->assertEquals(pow(2, 7*8), $uint2->get());
+    }
+
     public function testUs()
     {
         $u8 = new U8();