zlib: use `.bytesWritten` instead of `.bytesRead`

The introduction of `.bytesRead` to zlib streams was unfortunate,
because other streams in Node.js core use the exact opposite naming
of `.bytesRead` and `.bytesWritten`.

While one could see how the original naming makes sense in
a `Transform` stream context, we should try to work towards more
consistent APIs in core for these things.

This introduces `zlib.bytesWritten` and documentation-only deprecates
`zlib.bytesRead`.

PR-URL: https://github.com/nodejs/node/pull/19414
Refs: https://github.com/nodejs/node/issues/8874
Refs: https://github.com/nodejs/node/pull/13088
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: Сковорода Никита Андреевич <chalkerx@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Sakthipriyan Vairamani <thechargingvolcano@gmail.com>
Reviewed-By: Ruben Bridgewater <ruben@bridgewater.de>

1 files changed, 9 insertions, 7 deletions

diff --git a/test/parallel/test-zlib-bytes-read.js b/test/parallel/test-zlib-bytes-read.js
index 6262c25149..493478e78d 100644
--- a/test/parallel/test-zlib-bytes-read.js
+++ b/test/parallel/test-zlib-bytes-read.js
@@ -33,13 +33,13 @@ for (const method of [
   const comp = zlib[method[0]]();
   comp.on('data', function(d) {
     compData = Buffer.concat([compData, d]);
-    assert.strictEqual(this.bytesRead, compWriter.size,
+    assert.strictEqual(this.bytesWritten, compWriter.size,
                        `Should get write size on ${method[0]} data.`);
   });
   comp.on('end', common.mustCall(function() {
-    assert.strictEqual(this.bytesRead, compWriter.size,
+    assert.strictEqual(this.bytesWritten, compWriter.size,
                        `Should get write size on ${method[0]} end.`);
-    assert.strictEqual(this.bytesRead, expectStr.length,
+    assert.strictEqual(this.bytesWritten, expectStr.length,
                        `Should get data size on ${method[0]} end.`);
 
     {
@@ -49,12 +49,12 @@ for (const method of [
       const decomp = zlib[method[1]]();
       decomp.on('data', function(d) {
         decompData = Buffer.concat([decompData, d]);
-        assert.strictEqual(this.bytesRead, decompWriter.size,
+        assert.strictEqual(this.bytesWritten, decompWriter.size,
                            `Should get write size on ${method[0]}/` +
                            `${method[1]} data.`);
       });
       decomp.on('end', common.mustCall(function() {
-        assert.strictEqual(this.bytesRead, compData.length,
+        assert.strictEqual(this.bytesWritten, compData.length,
                            `Should get compressed size on ${method[0]}/` +
                            `${method[1]} end.`);
         assert.strictEqual(decompData.toString(), expectStr,
@@ -74,14 +74,16 @@ for (const method of [
       const decomp = zlib[method[1]]();
       decomp.on('data', function(d) {
         decompData = Buffer.concat([decompData, d]);
-        assert.strictEqual(this.bytesRead, decompWriter.size,
+        assert.strictEqual(this.bytesWritten, decompWriter.size,
                            `Should get write size on ${method[0]}/` +
                            `${method[1]} data.`);
       });
       decomp.on('end', common.mustCall(function() {
-        assert.strictEqual(this.bytesRead, compData.length,
+        assert.strictEqual(this.bytesWritten, compData.length,
                            `Should get compressed size on ${method[0]}/` +
                            `${method[1]} end.`);
+        // Checking legacy name.
+        assert.strictEqual(this.bytesWritten, this.bytesRead);
         assert.strictEqual(decompData.toString(), expectStr,
                            `Should get original string on ${method[0]}/` +
                            `${method[1]} end.`);