Only apply /-prefix handling to special URL-like specifiers

[domenic]

Closes #166.

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Preview | Diff

[guybedford]

The text and restriction seem like a good approach to me.

I just hope we don't restrict custom builtin schemes and alternative schemes though.

For example we might want to include safelisted schemes - whatwg/html#5482.

[guybedford]

When would asURL be null here if the invariant is that it is already normalized?

[domenic]

asURL is null if normalizedSpecifier is something like "moment".

[hiroshige-g]

LGTM

[hiroshige-g]

Could you add HTTP, WSS (and HTTPS) schemes?
HTTPS scheme is tested elsewhere, but HTTP and WSS schemes are not tested at all.

[hiroshige-g]

FYI this section currently needs blink internals APIs on WPT+Chromium, as data:, about: etc. schemes cannot be intercepted by service workers. I'll create a separate PR to move this section to e.g. url-specifiers-internal.json.

[hiroshige-g]

Or you can split this section in this PR out to a separate file like:

{
  "importMap": {
    "imports": {
      "data:text/": "/lib/test-data/",
      "about:text/": "/lib/test-about/",
      "blob:text/": "/lib/test-blob/",
      "blah:text/": "/lib/test-blah/",
      "file:text/": "/lib/test-file/",
      "ftp:text/": "/lib/test-ftp/",
      "ws:text/": "/lib/test-ws/"
    }
  },
  "importMapBaseURL": "https://example.com/app/index.html",
  "baseURL": "https://example.com/js/app.mjs",
  "name": "URL-like specifiers",
  "tests": {
    "Non-special vs. special schemes": {
      "expectedResults": {
        "data:text/javascript,console.log('foo')": "data:text/javascript,console.log('foo')",
        "data:text/": "https://example.com/lib/test-data/",
        "about:text/foo": "about:text/foo",
        "about:text/": "https://example.com/lib/test-about/",
        "blob:text/foo": "blob:text/foo",
        "blob:text/": "https://example.com/lib/test-blob/",
        "blah:text/foo": "blah:text/foo",
        "blah:text/": "https://example.com/lib/test-blah/",
        "ftp:text/foo": "https://example.com/lib/test-ftp/foo",
        "ftp:text/": "https://example.com/lib/test-ftp/",
        "file:text/foo": "https://example.com/lib/test-file/foo",
        "file:text/": "https://example.com/lib/test-file/",
        "ws:text/foo": "https://example.com/lib/test-ws/foo",
        "ws:text/": "https://example.com/lib/test-ws/"
      }
    }
  }
}

[domenic]

I split it out into a separate file, and included HTTP, HTTPS, and WSS.

[hiroshige-g]

FYI Chromium CL: https://chromium-review.googlesource.com/c/chromium/src/+/2491594

[domenic]

I just hope we don't restrict custom builtin schemes and alternative schemes though.

For example we might want to include safelisted schemes - whatwg/html#5482.

Protocol handlers only apply to navigation, not to resource fetching, so I don't think that would be the right layering.