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Remove current namespace wording from the current draft. (WICG#182)
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@otherdaniel
otherdaniel authored Nov 24, 2022
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Expand Up @@ -596,11 +596,10 @@ A given |attribute| belonging to an |element| matches an
[=attribute match list=], if the |attribute| is a key in the match list,
and |element| or `"*"` are found in the |attribute|'s value list.

For elements in the [[HTML namespace]] and non-namespaced attributes - i.e.,
what one may think of as normal [[HTML]] elements and attributes - elements
are named by their [=Element/local name=], and
[=Attr/local name|attributes, too=]. For "foreign" elements and attributes,
the rules are explained in the [[#namespaces]] chapter below.
Element names are interpreted as names in the [[HTML namespace]] and
non-namespaced attributes - i.e., what one may think of as normal [[HTML]]
elements and attributes. Elements are named by their [=Element/local name=], and
[=Attr/local name|attributes, too=].

<pre class="idl">
typedef record&lt;DOMString, sequence&lt;DOMString>> AttributeMatchList;
Expand Down Expand Up @@ -628,82 +627,6 @@ Examples for attributes and attribute match lists:
```
</div>

## Namespaces ## {#namespaces}

The [[HTML]] spec embeds [[HTML#svg-0|SVG]] and [[HTML#mathml|MathML]] content
and supports several [[HTML#attributes-2|namespaced attributes]].
To support these, the [=configuration dictionary=] supports
namespaced element and attribute names in the [=attribute match lists=].

The Sanitizer API uses the namespace model and namespace restrictions
of the [[HTML]] specification, and to support exactly as much namespaced
content as HTML does. When specifying element names, a set of fixed namespace
designators can be used to designate elements in the non-default namespaces.
Namespace designator and element names are seperated by a
colon (`":"`, U+003A) character. The following namespace designators are
recognized:
* `svg`: designates elements in the [=SVG namespace=].
* `math`: designates elements in the [=MathML namespace=].
* All elements without namespace designator are in the [=HTML namespace=].

No other namespace designators are valid.

<div class="example">
* `"p"`: The `p` element in the [=HTML namespace=].
* `"svg:line"`: The `line` element in the [=SVG namespace=].
* `"math:mfrac"`: The `mfrac` element in the [=MathML namespace=].
* `"dc:contributor"`: Invalid. This does not designate an element, and
will not match anything.
* `"svg"`: The `svg` element in the [=HTML namespace=].
<br>
Note the apparent
mismatch between the element name and the namespace it is in. This example
is valid, but is almost certainly not what the author intended. The
HTML parser has rules to translate the `<svg>` token into the `svg` element
in the [=SVG namespace=] (assuming a proper parsing context), while the
Sanitizer API does not.
* `"svg:svg"`: The `svg` element in the [=SVG namespace=].

</div>

Note: The [[HTML]] specification solves the problem of distinguishing HTML
from "foreign" elements largely through the parse context. This distinction
isn't available to the Sanitizer [=configuration dictionary=], since there is no
hierarchy or other relationship between configuration items. Therefore,
we introduce the explicit namespace designator.

Note: The colon (`":"`, U+003A) character is a valid character in
[[HTML#start-tags|HTML tag names]].
But because we use it here unconditionally
to designate namespaces, it is not possible to add a name with a colon in it
to an [=element allow list=]. Therefore all such elements would be blocked,
regardless of the configuration.

Attributes follow the syntax of [[HTML#attributes-2|HTML]], specifically the
table at the end of the subsection. The attribute names listed there will be
recognized as being in the namespace also listed there. No other namespaced
attributes will be recognized.

<div class="example">
* `lang`: An attribute named `lang`, which is not in any namespace.
* `xml:lang`: An attribute named `lang` in the namespace
`"http://www.w3.org/XML/1998/namespace"`, commonly known as the
[=XML namespace=].
* `my:lang`: An attribute `my:lang`, which is not in any namespace.
This is valid, but probably not what you want.

</div>

Note: This Sanitizer API makes no attempt at supporting arbitrary namespaces
or the [[XML-NAMES|Namespaces in XML]] specification in
general. We restrict notation and other support to the element and attribute
namespaces supported in the [[HTML]] specification, and there are no
recognized namespace designators other that the ones listed here.

<wpt>
sanitizer-names.https.html
</wpt>

# Algorithms # {#algorithms}

## API Implementation ## {#api-algorithms}
Expand All @@ -712,9 +635,6 @@ sanitizer-names.https.html
To <dfn>create a Sanitizer</dfn> with an optional |config| parameter, run
these steps:
1. Create a copy of |config|.
1. Normalize all element names in |config|'s copy by running the
[=normalize element name=] algorithm on each of them.
1. Remove all element names that were normalized to `null`.
1. Set |config| as [=this=]'s [=configuration dictionary=].

Issue(148): This should explicitly state the config's properties in which element names are found and modify the config wih map operations.
Expand All @@ -724,22 +644,6 @@ Note: The configuration object contains element names in the
[=element allow list=], [=element block list=], and [=element drop list=], and
in the mapped values in the [=attribute allow list=] and [=attribute drop list=].

<div algorithm="normalize element name">
To <dfn>normalize element name</dfn> |name|, run these steps:
1. Let |tokens| be the result of
[=strictly split a string|strictly splitting=] |name| on the delimiter
":" (U+003A).
1. If |tokens|' [=list/size=] is 1, then return |tokens|[0].
1. If |tokens|' [=list/size=] is 2 and
|tokens|[0] [=string/is=] either "svg" or "math", then:
1. Adjust |tokens|[1] as described in the "any other start tag"
branch of [the rules for parsing tokens in foreign content](https://html.spec.whatwg.org/multipage/parsing.html#parsing-main-inforeign)
subchapter in the HTML parsing spec.
1. Return the [=concatenation=] of the [=/list=]
&#x00AB;`|tokens|[0]`,`":"` (U+003A),`|tokens|[1]`&#x00BB;.
1. Return `null`.
</div>

<div algorithm="sanitize">
To <dfn>sanitize</dfn> a given |input| of type `Document or DocumentFragment`
run these steps:
Expand Down Expand Up @@ -954,26 +858,9 @@ sanitizer-unknown.https.html
To determine whether an <dfn>|element| matches an element |name|</dfn>,
run these steps:

1. Let |tokens| be the result of running the
[=strictly split a string=] algorithm on |name| with the delimiter
":" (U+003A).
1. If |tokens|' [=list/size=] is 1,
and if |element| is in the [=HTML namespace=]
and if |element|'s [=Element/local name=] is
[=identical to=] |tokens|[0]:
Return `true`.
1. If |tokens|' [=list/size=] is 2,
and if [tokens|[0] is "svg"
and if |element| is in the [=SVG namespace=]
and if |element|'s [=Element/local name=] is
[=identical to=] to |tokens|[1]:
Return `true`.
1. If |tokens|'s [=list/size=] is 2,
and if |tokens|[0] is "math"
and if |element| is in the [=MathML namespace=]
1. If |element| is in the [=HTML namespace=]
and if |element|'s [=Element/local name=] is
[=identical to=] |tokens|[1]:
Return `true`.
[=identical to=] |name|: Return `true`.
1. Return `false`.
</div>

Expand All @@ -983,30 +870,17 @@ Issue(146): Whitespaces or colons?
To determine whether an <dfn>|attribute| matches an [=attribute match
list=]</dfn> |list|, run these steps:

1. If |attribute|'s [=Attr/namespace=] is not `null`: Return `false`.
1. If |attribute|'s [=Attr/local name=] does not match the
[=attribute match list=] |list|'s
[key](https://webidl.spec.whatwg.org/#idl-record) and if the key is
not `"*"`: Return `false`.
1. Let |element| be the |attribute|'s {{Element}}.
1. Let |element name| be |element|'s [=Element/local name=].
1. If |element| is a in either the [=SVG namespace|SVG=] or
[=MathML namespace|MathML=] namespaces (i.e., it's a
[foreign element](https://html.spec.whatwg.org/#foreign-elements)),
then prefix |element name| with the appropriate
[[#namespaces|namespace designator]] plus a whitespace
character.
1. If |list|'s [value](https://webidl.spec.whatwg.org/#idl-record) does not
contain |element name| and value is not `["*"]`: Return `false`.
1. Return `true`.

Issue(146): This algorithm is still using a whitespace.

Note: The element names in the Sanitizer configuration are normalized according
to normalization step in the HTML Parser, just like elements'
[=Element/local names=] are. Thus, the comparison is effectively case
insensitive.
</div>

<div algorithm="sanitize action for an attribute">
To determine the <dfn>sanitize action for an |attribute|</dfn> given a Sanitizer
configuration dictionary |config|, run these steps:
Expand Down

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