gulp-sourcemaps support

[ksmithut]

Have you considered adding sourcemaps support?

[efolio]

+1

[tracker1]

@ksmithut do you have a suggestion how this would be supported? This module only changes the data for the outbound script file... if you have something that generates source maps, can't you just do it before this module?

[ksmithut]

You can, but if you use this module after the sourcemaps, it will also add the header to the sourcemap file because the sourcemap is added to the pipeline. The gulp-sourcemaps plugin has some kind of API, but I personally haven't thought much about it.

Honestly, I was just wondering if you were going to think of supporting it. From what I understand about sourcemaps, its a very complex process, and even more so with a gulp workflow. If you don't plan on supporting (and I wouldn't blame you), go ahead and close this out.

I might have some time during the next few weeks to investigate if you would like.

[tracker1]

If you can come up with a PR that doesn't add a dependency (other than the obvious dev dependency) with appropriate tests, I'll take the PR. I wish I had time to look into this (as well as a dozen other things)...

Been meaning to add sourcemaps into a couple projects I'm working on (in conjunction with es6 transpiling). I'm pretty test heavy, so haven't needed them so much, but when I have it would be really nice.

[dmitrijs]

+1

[ksmithut]

@tracker1 In order to add sourcemap support, I'll need to add one dependency vinyl-sourcemaps-apply. If it's still not okay to add a dependency, I'll leave this to you or someone else. Seems like a pretty easy integration though with that module.

[tracker1]

@contra @robrich @phated any input on this one?

[yocontra]

Yep just use the standard gulp-sourcemaps (vinyl-sourcemaps-apply and whatever else) toolkit. There is info on how to add sourcemaps to your plugin on one of those pages.

[yocontra]

https://github.com/floridoo/gulp-sourcemaps#plugin-developers-only-how-to-add-source-map-support-to-plugins

[tracker1]

@contra thanks for chiming in... @ksmithut if you generate a PR, I'm happy to add it, otherwise will probably get to this next week.

[ksmithut]

@tracker1 I've jumped into sourcemap support, but I'm running into a few cases where sourcemaps might not make sense. What if someone adds code to the header to be consumed? How will that be mapped back? I mean, we could always include another file in the sourcemap, but that is turning out to be more complicated than I anticipated. This is really my first time working with generating sourcemaps.

I've looked through the documentation that @contra linked to, but it doesn't actually show how to apply the sourcemaps. The example assumes that the transformation plugin already has sourcemap support. Because this is simply prepending content onto the Buffer/Stream, we would need to write the sourcemap generator for this. Although it seems simple, this is really the first time I've done anything with sourcemap generation. If any of you have any links to resources on how to do this, I could try and muddle my way through it.

[tracker1]

Looks like you should just be able to use gulp-sourcemaps

var gulp = require("gulp");
var sourcemaps = require("gulp-sourcemaps");
var header = require("gulp-header");
var headerText = require("fs").readSync(__dirname + "/txt/header.js", {encoding:utf8});

gulp.task("default", function () {
  return gulp.src(...)
    .pipe(sourcemaps.init())
    ......
    .pipe(header(headerText))
    .pipe(sourcemaps.write("."))
    .pipe(gulp.dest("dist"));
});

As to bringing in a header with code, I'd presume that you're probably going to concat, in which case, you can put the header at the beginning of your input thunk...

gulp.src([
  'header.js'
  ,'src/app/index.js'
])
.pipe(sourcemaps.init())
.pipe(concat())
...

[yocontra]

@tracker1 No, using gulp-sourcemaps won't make sourcemaps start working. All gulp-sourcemaps does it take the file.sourceMaps array, flatten it down into one, and convert it to either a file or an inline comment. You should reopen this.

[nervo]

👍 on supporting sourcemaps

[knpwrs]

👍 As well.

[kasperisager]

Just adding another 👍

[vrockai]

I've just left the gulp-header plugin today and used (ugly) gulp-concat workaround (just to prepend licence string) instead, only because of this issue. Big 👍 to resolving this.

[JeremyJames]

👍

[JeremyFagis]

👍 👍

[tracker1]

@vrockai any chance you could post your gulpfile with concat that is working... I haven't had a chance to dig through this, but will need it myself in a few weeks.

[vrockai]

@tracker1 , I'm just using temporary file; ugly, but working:
vrockai/hawkular-ui-components@83aac47#diff-b20c7230de4da834e815c06534cab810R124

[madhums]

Sent a PR #16