test: fix buffer writes on mips

Mips has a different way of handling NaN. This makes sure the tests
pass on MIPS as well.

PR-URL: #20377
Reviewed-By: Richard Lau <[email protected]>

Author: BridgeAR

test/parallel/test-buffer-writedouble.js

@@ -67,10 +67,19 @@ assert.strictEqual(buffer.readDoubleLE(8), -Infinity);
 buffer.writeDoubleBE(NaN, 0);
 buffer.writeDoubleLE(NaN, 8);
 
-assert.ok(buffer.equals(new Uint8Array([
-  0x7F, 0xF8, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
-  0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xF8, 0x7F
-])));
+// JS only knows a single NaN but there exist two platform specific
+// implementations. Therefore, allow both quiet and signalling NaNs.
+if (buffer[1] === 0xF7) {
+  assert.ok(buffer.equals(new Uint8Array([
+    0x7F, 0xF7, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
+    0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xF7, 0x7F
+  ])));
+} else {
+  assert.ok(buffer.equals(new Uint8Array([
+    0x7F, 0xF8, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+    0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xF8, 0x7F
+  ])));
+}
 
 assert.ok(Number.isNaN(buffer.readDoubleBE(0)));
 assert.ok(Number.isNaN(buffer.readDoubleLE(8)));

test/parallel/test-buffer-writefloat.js

@@ -50,8 +50,18 @@ assert.strictEqual(buffer.readFloatLE(4), -Infinity);
 
 buffer.writeFloatBE(NaN, 0);
 buffer.writeFloatLE(NaN, 4);
-assert.ok(buffer.equals(
-  new Uint8Array([ 0x7F, 0xC0, 0x00, 0x00, 0x00, 0x00, 0xC0, 0x7F ])));
+
+// JS only knows a single NaN but there exist two platform specific
+// implementations. Therefore, allow both quiet and signalling NaNs.
+if (buffer[1] === 0xBF) {
+  assert.ok(
+    buffer.equals(new Uint8Array(
+      [ 0x7F, 0xBF, 0xFF, 0xFF, 0xFF, 0xFF, 0xBF, 0x7F ])));
+} else {
+  assert.ok(
+    buffer.equals(new Uint8Array(
+      [ 0x7F, 0xC0, 0x00, 0x00, 0x00, 0x00, 0xC0, 0x7F ])));
+}
 
 assert.ok(Number.isNaN(buffer.readFloatBE(0)));
 assert.ok(Number.isNaN(buffer.readFloatLE(4)));