Support colour output in stdout for jupyter and julia engines

[MichaelHatherly]

Description

This adds support for printing colour output from stdout and stderr in the jupyter and julia backends. Only applies to HTML output.

Fixes #12117.

Checklist

I have (if applicable):

• filed a contributor agreement.
• referenced the GitHub issue this PR closes
• updated the appropriate changelog in the PR
• ensured the present test suite passes
• added new tests
• created a separate documentation PR in Quarto's website repo and linked it to this PR

[MichaelHatherly]

Still to add some tests and update the changelog. I'll do that once I've familiarised myself with https://github.com/quarto-dev/quarto-cli/blob/main/tests/README.md

[cscheid]

@MichaelHatherly The easiest way to add tests is, by far, to use the _quarto: tests: key. Here's an example:

---
format: html
_quarto:
  tests:
    html:
      ensureFileRegexMatches:
        - ["Nunc ac dignissim magna. Vestibulum vitae egestas elit."]
---

{{< lipsum 2 >}}

In our test suite, every document inside tests/docs/smoke-all is rendered and tested using the _quarto: tests: functionality.

For the example above, the behavior is very simple: it's asking for the HTML format output to respect a given regex.

Checking in a document with this syntax is enough for our test suite to run it, but during development there is a more convenient option. If you're running a dev build of quarto, you should have a ./tests/run-fast-tests.sh script. This script takes .qmd files as parameters and runs them in the test suite infrastructure. As a minimal test, you could do something like the following:

$ cd tests/docs/smoke-all
$ cat > this-test-will-fail.qmd
---
format: html
_quarto:
  tests:
    html:
      ensureFileRegexMatches:
        - []
        - ["Forbidden"]
---

Forbidden
^D
$ cd ../..
$ ./run-fast-tests.sh ./docs/smoke-all/this-test-will-fail.qmd
docs/smoke-all/this-test-will-fail.qmd
running 1 test from ./smoke/smoke-all.test.ts
[smoke] > quarto render docs/smoke-all/this-test-will-fail.qmd --to html ...
------- output -------
[verify] > Inspecting docs/smoke-all/this-test-will-fail.html for Regex matches
----- output end -----
[smoke] > quarto render docs/smoke-all/this-test-will-fail.qmd --to html ... FAILED (3s)

 ERRORS

[smoke] > quarto render docs/smoke-all/this-test-will-fail.qmd --to html => ./test.ts:329:8
error: AssertionError: Failed assertion:

--------------------------------------------------------------------------------
[smoke] > quarto render docs/smoke-all/this-test-will-fail.qmd --to html
          ./run-tests.sh smoke/smoke-all.test.ts

[verify] > Inspecting docs/smoke-all/this-test-will-fail.html for Regex matches

Illegal match /Forbidden/m was found in file docs/smoke-all/this-test-will-fail.html.
AssertionError: Illegal match /Forbidden/m was found in file docs/smoke-all/this-test-will-fail.html.
    at Module.assert (https://jsr.io/@std/assert/0.224.0/assert.ts:18:11)
    at assert (https://jsr.io/@std/testing/0.224.0/asserts.ts:608:11)
    at file:///Users/cscheid/repos/github/quarto-dev/quarto-cli/tests/verify.ts:389:7
    at Array.forEach (<anonymous>)
    at regexChecker (file:///Users/cscheid/repos/github/quarto-dev/quarto-cli/tests/verify.ts:388:15)
    at eventLoopTick (ext:core/01_core.js:175:7)
    at async Object.verify (file:///Users/cscheid/repos/github/quarto-dev/quarto-cli/tests/verify.ts:416:9)
    at async fn (file:///Users/cscheid/repos/github/quarto-dev/quarto-cli/tests/test.ts:240:15)
    at async innerWrapped (ext:cli/40_test.js:191:5)
    at async outerWrapped (ext:cli/40_test.js:134:14)

OUTPUT:
    pandoc
    to: html
    output-file: this-test-will-fail.html
    standalone: true
    section-divs: true
    html-math-method: mathjax
    wrap: none
    default-image-extension: png
    variables: {}

    metadata
    document-css: false
    link-citations: true
    date-format: long
    lang: en

    Output created: this-test-will-fail.html

    throw new AssertionError(msg);
          ^
    at assert (https://jsr.io/@std/assert/0.224.0/assert.ts:18:11)
    at Module.fail (https://jsr.io/@std/assert/0.224.0/fail.ts:17:3)
    at fail (https://jsr.io/@std/testing/0.224.0/asserts.ts:663:11)
    at fn (file:///Users/cscheid/repos/github/quarto-dev/quarto-cli/tests/test.ts:303:11)

 FAILURES

[smoke] > quarto render docs/smoke-all/this-test-will-fail.qmd --to html => ./test.ts:329:8

FAILED | 0 passed | 1 failed (3s)

error: Test failed

In this test, we're asking the test suite to fail if the Forbidden regex is matched.

Some example checkers:

• ensureFileRegexMatches: works in every format (but is tricky for binary formats, see below)
• html has ensureHtmlElements which takes CSS selector lists
• docx:
  • ensureDocxRegexMatches: extracts the content XML from the binary output and then runs a regex check
  • ensureDocxXPath: extracts the XML from the docx format and then checks for the XPath selector

The full suite isn't document but is at tests/verify.ts.

[MichaelHatherly]

Thank you for those details @cscheid, very helpful!