UglifyJS minifying fails on some advanced scripting examples

[GameSoul7Eugene]

Problem description

If you export the following scripting examples to HTML5 with UglifyJS, they will fail to launch in the browser after exporting (although there will be no errors when exporting and minifying in C3). None of them break in the Bundle only minify mode.

Complex Terrain [breaks in Simple and Advanced minify modes] Integrated 3D engine [breaks only in Advanced minify mode] Snowboard 3D [breaks in Simple and Advanced minify modes]

Observed result

Complex Terrain

Simple

Advanced

Snowboard 3D

Simple

Advanced

Integrated 3D engine

Advanced

Expected result

These projects have no errors after exporting, no matter what minify mode they used!

More details

Affected browsers/platforms: any

First affected release: r403 as it was the first release to add the UglifyJS minifier.

System details

View details

Platform information Product: Construct 3 r403 (beta) Browser: Firefox 129.0 Browser engine: Gecko Context: browser Operating system: Windows 10 Device type: desktop Device pixel ratio: 1 Logical CPU cores: 8 Approx. device memory: (unavailable) User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:129.0) Gecko/20100101 Firefox/129.0 Language setting: en-US Local storage Storage quota (approx): 10 gb Storage usage (approx): 45 mb (0.4%) Persistant storage: No Browser support notes This list contains missing features that are not required, but could improve performance or user experience if supported. Rendering multiple on-screen Layout Views is slow in Firefox due to [bug 1163426](https://bugzilla.mozilla.org/show_bug.cgi?id=1163426) Determining input device capabilities is not supported. WebGL information Version string: WebGL 2.0 Numeric version: 2 Supports NPOT textures: yes Supports GPU profiling: no Supports highp precision: yes Vendor: Google Inc. (Intel) Renderer: ANGLE (Intel, Intel(R) HD Graphics Direct3D11 vs_5_0 ps_5_0), or similar Major performance caveat: no Maximum texture size: 16384 Point size range: 1 to 1024 Extensions: EXT_color_buffer_float EXT_float_blend EXT_texture_compression_bptc EXT_texture_compression_rgtc EXT_texture_filter_anisotropic OES_draw_buffers_indexed OES_texture_float_linear OVR_multiview2 WEBGL_compressed_texture_s3tc WEBGL_compressed_texture_s3tc_srgb WEBGL_debug_renderer_info WEBGL_debug_shaders WEBGL_lose_context WEBGL_provoking_vertex Audio information System sample rate: 48000 Hz Output channels: 2 Output interpretation: speakers Supported decode formats: WebM Opus (audio/webm;codecs=opus) WebM Vorbis (audio/webm;codecs=vorbis) MPEG-4 Opus (audio/mp4;codecs=opus) MPEG-4 AAC (audio/mp4;codecs=mp4a.40.2) MP3 (audio/mpeg) FLAC (audio/flac) PCM WAV (audio/wav;codecs=1) Supported encode formats: WebM Opus (audio/webm;codecs=opus) Video information Supported decode formats: WebM AV1 (video/webm;codecs=av01.0.00M.08) WebM VP9 (video/webm;codecs=vp9) WebM VP8 (video/webm;codecs=vp8) MPEG-4 AV1 (video/mp4;codecs=av01.0.00M.08) MPEG-4 VP9 (video/mp4;codecs=vp9) MPEG-4 H.264 (video/mp4;codecs=avc1.420034) Supported encode formats: WebM VP8 (video/webm;codecs=vp8)

[AshleyScirra]

I think the issues with simple mode come down to a bug in UglifyJS - I've reported it to them here: https://github.com/mishoo/UglifyJS/issues/5927 That will be followed up there.

As for the Integrated 3D engine example, that doesn't work after an advanced minify export with Closure Compiler either. I suspect that's just because it bundles a significant part of the three.js engine, and that the library has not been written to comply with the restrictions of advanced mode minification (e.g. mixing string and dot property syntax). To fix that you'd likely need to follow up with the three.js project.

[AshleyScirra]

FWIW I debugged three.js a bit and identified it indeed is not written to support advanced minification, and I submitted a feature request describing the problem and how to fix it.

[AshleyScirra]

FWIW I also identified the setting in UglifyJS that causes the bug with simple minified exports, and disabled it on the server-side, so UglifyJS exports should now work with the other samples (not using three.js) in simple or advanced minify mode.