buffer: added support for writing NaN and Infinity

to writeDoubleBE(), writeDoubleLE(), writeFloatBE() and writeFloatLE().
Fixes #3934.

lib/buffer.js

@@ -1025,10 +1025,14 @@ function verifsint(value, max, min) {
   assert.ok(Math.floor(value) === value, 'value has a fractional component');
 }
 
-function verifIEEE754(value, max, min) {
+function verifyIEEE754(value, max, min) {
   assert.ok(typeof (value) == 'number',
       'cannot write a non-number as a number');
 
+  if (isNaN(value) || value === Infinity || value === -Infinity) {
+    return;
+  }
+
   assert.ok(value <= max, 'value larger than maximum allowed value');
 
   assert.ok(value >= min, 'value smaller than minimum allowed value');
@@ -1135,7 +1139,7 @@ function writeFloat(buffer, value, offset, isBigEndian, noAssert) {
     assert.ok(offset + 3 < buffer.length,
         'Trying to write beyond buffer length');
 
-    verifIEEE754(value, 3.4028234663852886e+38, -3.4028234663852886e+38);
+    verifyIEEE754(value, 3.4028234663852886e+38, -3.4028234663852886e+38);
   }
 
   require('buffer_ieee754').writeIEEE754(buffer, value, offset, isBigEndian,
@@ -1164,7 +1168,7 @@ function writeDouble(buffer, value, offset, isBigEndian, noAssert) {
     assert.ok(offset + 7 < buffer.length,
         'Trying to write beyond buffer length');
 
-    verifIEEE754(value, 1.7976931348623157E+308, -1.7976931348623157E+308);
+    verifyIEEE754(value, 1.7976931348623157E+308, -1.7976931348623157E+308);
   }
 
   require('buffer_ieee754').writeIEEE754(buffer, value, offset, isBigEndian,

test/simple/test-writedouble.js

@@ -123,6 +123,69 @@ function test(clazz) {
   ASSERT.equal(0x00, buffer[13]);
   ASSERT.equal(0x00, buffer[14]);
   ASSERT.equal(0x80, buffer[15]);
+
+  buffer.writeDoubleBE(Infinity, 0);
+  buffer.writeDoubleLE(Infinity, 8);
+  ASSERT.equal(0x7F, buffer[0]);
+  ASSERT.equal(0xF0, buffer[1]);
+  ASSERT.equal(0x00, buffer[2]);
+  ASSERT.equal(0x00, buffer[3]);
+  ASSERT.equal(0x00, buffer[4]);
+  ASSERT.equal(0x00, buffer[5]);
+  ASSERT.equal(0x00, buffer[6]);
+  ASSERT.equal(0x00, buffer[7]);
+  ASSERT.equal(0x00, buffer[8]);
+  ASSERT.equal(0x00, buffer[9]);
+  ASSERT.equal(0x00, buffer[10]);
+  ASSERT.equal(0x00, buffer[11]);
+  ASSERT.equal(0x00, buffer[12]);
+  ASSERT.equal(0x00, buffer[13]);
+  ASSERT.equal(0xF0, buffer[14]);
+  ASSERT.equal(0x7F, buffer[15]);
+  ASSERT.equal(Infinity, buffer.readDoubleBE(0));
+  ASSERT.equal(Infinity, buffer.readDoubleLE(8));
+
+  buffer.writeDoubleBE(-Infinity, 0);
+  buffer.writeDoubleLE(-Infinity, 8);
+  ASSERT.equal(0xFF, buffer[0]);
+  ASSERT.equal(0xF0, buffer[1]);
+  ASSERT.equal(0x00, buffer[2]);
+  ASSERT.equal(0x00, buffer[3]);
+  ASSERT.equal(0x00, buffer[4]);
+  ASSERT.equal(0x00, buffer[5]);
+  ASSERT.equal(0x00, buffer[6]);
+  ASSERT.equal(0x00, buffer[7]);
+  ASSERT.equal(0x00, buffer[8]);
+  ASSERT.equal(0x00, buffer[9]);
+  ASSERT.equal(0x00, buffer[10]);
+  ASSERT.equal(0x00, buffer[11]);
+  ASSERT.equal(0x00, buffer[12]);
+  ASSERT.equal(0x00, buffer[13]);
+  ASSERT.equal(0xF0, buffer[14]);
+  ASSERT.equal(0xFF, buffer[15]);
+  ASSERT.equal(-Infinity, buffer.readDoubleBE(0));
+  ASSERT.equal(-Infinity, buffer.readDoubleLE(8));
+
+  buffer.writeDoubleBE(NaN, 0);
+  buffer.writeDoubleLE(NaN, 8);
+  ASSERT.equal(0x7F, buffer[0]);
+  ASSERT.equal(0xF0, buffer[1]);
+  ASSERT.equal(0x00, buffer[2]);
+  ASSERT.equal(0x00, buffer[3]);
+  ASSERT.equal(0x00, buffer[4]);
+  ASSERT.equal(0x00, buffer[5]);
+  ASSERT.equal(0x00, buffer[6]);
+  ASSERT.equal(0x01, buffer[7]);
+  ASSERT.equal(0x01, buffer[8]);
+  ASSERT.equal(0x00, buffer[9]);
+  ASSERT.equal(0x00, buffer[10]);
+  ASSERT.equal(0x00, buffer[11]);
+  ASSERT.equal(0x00, buffer[12]);
+  ASSERT.equal(0x00, buffer[13]);
+  ASSERT.equal(0xF0, buffer[14]);
+  ASSERT.equal(0x7F, buffer[15]);
+  ASSERT.ok(isNaN(buffer.readDoubleBE(0)));
+  ASSERT.ok(isNaN(buffer.readDoubleLE(8)));
 }
 
 

test/simple/test-writefloat.js

@@ -83,6 +83,45 @@ function test(clazz) {
   ASSERT.equal(0x00, buffer[5]);
   ASSERT.equal(0x00, buffer[6]);
   ASSERT.equal(0x80, buffer[7]);
+
+  buffer.writeFloatBE(Infinity, 0);
+  buffer.writeFloatLE(Infinity, 4);
+  ASSERT.equal(0x7F, buffer[0]);
+  ASSERT.equal(0x80, buffer[1]);
+  ASSERT.equal(0x00, buffer[2]);
+  ASSERT.equal(0x00, buffer[3]);
+  ASSERT.equal(0x00, buffer[4]);
+  ASSERT.equal(0x00, buffer[5]);
+  ASSERT.equal(0x80, buffer[6]);
+  ASSERT.equal(0x7F, buffer[7]);
+  ASSERT.equal(Infinity, buffer.readFloatBE(0));
+  ASSERT.equal(Infinity, buffer.readFloatLE(4));
+
+  buffer.writeFloatBE(-Infinity, 0);
+  buffer.writeFloatLE(-Infinity, 4);
+  ASSERT.equal(0xFF, buffer[0]);
+  ASSERT.equal(0x80, buffer[1]);
+  ASSERT.equal(0x00, buffer[2]);
+  ASSERT.equal(0x00, buffer[3]);
+  ASSERT.equal(0x00, buffer[4]);
+  ASSERT.equal(0x00, buffer[5]);
+  ASSERT.equal(0x80, buffer[6]);
+  ASSERT.equal(0xFF, buffer[7]);
+  ASSERT.equal(-Infinity, buffer.readFloatBE(0));
+  ASSERT.equal(-Infinity, buffer.readFloatLE(4));
+
+  buffer.writeFloatBE(NaN, 0);
+  buffer.writeFloatLE(NaN, 4);
+  ASSERT.equal(0x7F, buffer[0]);
+  ASSERT.equal(0x80, buffer[1]);
+  ASSERT.equal(0x00, buffer[2]);
+  ASSERT.equal(0x01, buffer[3]);
+  ASSERT.equal(0x01, buffer[4]);
+  ASSERT.equal(0x00, buffer[5]);
+  ASSERT.equal(0x80, buffer[6]);
+  ASSERT.equal(0x7F, buffer[7]);
+  ASSERT.ok(isNaN(buffer.readFloatBE(0)));
+  ASSERT.ok(isNaN(buffer.readFloatLE(4)));
 }