Rotation angles that are not multiples of 90 ignore operation ordering

[iovdin]

521   System:
522     OS: macOS High Sierra 10.13.6
523     CPU: (4) x64 Intel(R) Core(TM) i5-3230M CPU @ 2.60GHz
524     Memory: 82.42 MB / 8.00 GB
525     Shell: 3.2.57 - /bin/bash
526   Binaries:
527     Node: 10.9.0 - ~/.nvm/versions/node/v10.9.0/bin/node
528     Yarn: 1.12.3 - ~/.yarn/bin/yarn
529     npm: 6.2.0 - ~/.nvm/versions/node/v10.9.0/bin/npm
530     Watchman: 4.9.0 - /usr/local/bin/watchman
531   Utilities:
532     CMake: 3.8.2 - /usr/local/bin/cmake
533     Make: 3.81 - /usr/bin/make
534     GCC: 4.2.1 - /usr/bin/gcc
535     Git: 2.13.2 - /usr/local/bin/git
536   Languages:
537     Bash: 3.2.57 - /bin/bash
538     Go: 1.8.3 - /usr/local/bin/go
539     Java: 1.8.0_77 - /usr/bin/javac
540     Perl: 5.18.2 - /usr/bin/perl
541     PHP: 7.1.23 - /usr/bin/php
542     Python: 2.7.12 - /Users/iovdin/projects/miniconda2/bin/python
543     Ruby: 2.3.7p456 - /usr/bin/ruby
544     Rust: 1.28.0 - /usr/local/bin/rustc

running this code

const fs = require('fs');
const sharp = require('sharp');
const https = require('https');

const picUrl = "https://www.cosy.sbg.ac.at/~pmeerw/Watermarking/lena_color.gif"

const pipeline = sharp()
  .rotate(45)
  .extract({ left: 100, top: 100, width: 312, height: 312 })

https.get(picUrl, (res) => {
  res.pipe(pipeline);
  pipeline.pipe(fs.createWriteStream('out.jpg'))
})

Both rotate, extract and extract, rotate order gives the same result image

What is the expected behaviour?
After the rotation, I'd expect extract work with rotated image

[lovell]

Hi, it looks like angles at multiples of 90 work as you would expect but sadly not other angles, support for which was introduced in #1385.

(Note to self/fixer: the rotation angle logic in JS should be simplified/refactored to remove the distinction between 90 and non-90 angles, moving the vips_rot vs vips_rotate decision into a separate internal C++ operation function.)

[lovell]

sharp v0.23.0 / libvips v8.8.1 is now available. Thank you for the PR to fix this!