[cssom] CSSStyleDeclaration.cssText should return the empty string for computed style.

emilio · Jordan Taylor · commit b5d604c91585 · 2020-05-13T09:51:54.000-07:00
Closes w3c#1033
diff --git a/cssom-1/Overview.bs b/cssom-1/Overview.bs
@@ -1808,7 +1808,7 @@ On setting the {{CSSStyleRule/selectorText}} attribute these steps must be run:
 The <dfn attribute for=CSSStyleRule>style</dfn> attribute must return a <code>CSSStyleDeclaration</code> object for the style rule, with the
 following properties:
 <dl>
- <dt><a for="CSSStyleDeclaration">readonly flag</a>
+ <dt><a for="CSSStyleDeclaration">computed flag</a>
  <dd>Unset.
  <dt><a for="CSSStyleDeclaration">declarations</a>
  <dd>The declared declarations in the rule, in <a>specified order</a>.
@@ -1908,7 +1908,7 @@ On setting the {{CSSPageRule/selectorText}} attribute  these steps must be run:
 The <dfn attribute for=CSSGroupingRule>style</dfn> attribute must return a <code>CSSStyleDeclaration</code> object for the
 <code>@page</code> at-rule, with the following properties:
 <dl>
- <dt><a for="CSSStyleDeclaration">readonly flag</a>
+ <dt><a for="CSSStyleDeclaration">computed flag</a>
  <dd>Unset.
  <dt><a for="CSSStyleDeclaration">declarations</a>
  <dd>The declared declarations in the rule, in <a>specified order</a>.
@@ -1938,7 +1938,7 @@ included in the name. [[!CSS3SYN]]
 The <dfn attribute for=CSSMarginRule>style</dfn> attribute must return a <code>CSSStyleDeclaration</code> object for the
 margin at-rule, with the following properties:
 <dl>
- <dt><a for="CSSStyleDeclaration">readonly flag</a>
+ <dt><a for="CSSStyleDeclaration">computed flag</a>
  <dd>Unset.
  <dt><a for="CSSStyleDeclaration">declarations</a>
  <dd>The declared declarations in the rule, in <a>specified order</a>.
@@ -1996,9 +1996,9 @@ the DOM a <a>CSS declaration block</a> is a
 <a>CSS declaration block</a> has the following associated properties:
 
 <dl dfn-for="CSSStyleDeclaration" export>
- <dt><dfn>readonly flag</dfn>
- <dd>Unset if the object can be manipulated. Set if it can not be
- manipulated. Unless otherwise stated it is unset.
+ <dt><dfn>computed flag</dfn>
+ <dd>Set if the object is a computed style declaration, rather than a specified
+     style. Unless otherwise stated it is unset.
 
  <dt><dfn>declarations</dfn>
  <dd>The <a>CSS declarations</a> associated with the object.
@@ -2099,7 +2099,7 @@ A <a>CSS declaration block</a> has these <a>attribute change steps</a> for its <
 with <var>localName</var>, <var>value</var>, and <var>namespace</var>:
 
 <ol>
- <li>If the <a for="CSSStyleDeclaration">readonly flag</a> is set, then return.
+ <li>If the <a for="CSSStyleDeclaration">computed flag</a> is set, then return.
  <li>If the <a for="CSSStyleDeclaration">updating flag</a> is set, then return.
  <li>If <var>localName</var> is not "<code>style</code>", or <var>namespace</var> is not null, then return.
  <li>If <var>value</var> is null, empty the <a for="CSSStyleDeclaration">declarations</a>.
@@ -2111,7 +2111,7 @@ When a <a>CSS declaration block</a> object is created, then:
 
 <ol>
  <li>Let <var>owner node</var> be the <a for="CSSStyleDeclaration">owner node</a>.
- <li>If <var>owner node</var> is null, or the <a for="CSSStyleDeclaration">readonly flag</a> is set, then return.
+ <li>If <var>owner node</var> is null, or the <a for="CSSStyleDeclaration">computed flag</a> is set, then return.
  <li>Let <var>value</var> be the result of <a lt="get an attribute by namespace and local name">getting an attribute</a>
  given null, "<code>style</code>", and <var>owner node</var>.
  <li>If <var>value</var> is not null, let the <a for="CSSStyleDeclaration">declarations</a> be the result of
@@ -2121,7 +2121,7 @@ When a <a>CSS declaration block</a> object is created, then:
 To <dfn export>update style attribute for</dfn> <var>declaration block</var> means to run the steps below:
 
 <ol>
- <li>Assert: <var>declaration block</var>'s <a for="CSSStyleDeclaration">readonly flag</a> is unset.
+ <li>Assert: <var>declaration block</var>'s <a for="CSSStyleDeclaration">computed flag</a> is unset.
  <li>Let <var>owner node</var> be <var>declaration block</var>'s <a for="CSSStyleDeclaration">owner node</a>.
  <li>If <var>owner node</var> is null, then return.
  <li>Set <var>declaration block</var>'s <a for="CSSStyleDeclaration">updating flag</a>.
@@ -2164,11 +2164,14 @@ The object's <a>supported property indices</a> are the numbers in the range zero
 <a>CSS declarations</a> in the <a for="CSSStyleDeclaration">declarations</a>. If there are no such
 <a>CSS declarations</a>, then there are no <a>supported property indices</a>.
 
-The <dfn attribute for=CSSStyleDeclaration>cssText</dfn> attribute must return the result of
-<a lt="serialize a CSS declaration block">serializing</a> the <a for="CSSStyleDeclaration">declarations</a>.
+Getting the <dfn attribute for="CSSStyleDeclaration">cssText</dfn> attribute must run these steps:
+
+1. If the <a for="CSSStyleDeclaration">computed flag</a> is set, then return the empty string.
+2. Return the result of <a lt="serialize a CSS declaration block">serializing</a> the <a for="CSSStyleDeclaration">declarations</a>.
+
 Setting the {{CSSStyleDeclaration/cssText}} attribute must run these steps:
 <ol>
- <li>If the <a for="CSSStyleDeclaration">readonly flag</a> is set,
+ <li>If the <a for="CSSStyleDeclaration">computed flag</a> is set,
  then <a>throw</a> a {{NoModificationAllowedError}} exception.
  <li>Empty the <a for="CSSStyleDeclaration">declarations</a>.
  <li><a lt="Parse a CSS declaration block">Parse</a> the given value and, if the return value is not the empty list, insert the items in the list
@@ -2234,7 +2237,7 @@ value would be "<code>important</code>".</div>
 
 The <dfn method for=CSSStyleDeclaration>setProperty(<var>property</var>, <var>value</var>, <var>priority</var>)</dfn> method must run these steps:
 <ol>
- <li>If the <a for="CSSStyleDeclaration">readonly flag</a> is set,
+ <li>If the <a for="CSSStyleDeclaration">computed flag</a> is set,
  then <a>throw</a> a {{NoModificationAllowedError}} exception.
  <li>If <var>property</var> is not a <a>custom property</a>, follow these substeps:
   <ol>
@@ -2349,7 +2352,7 @@ use different algorithms as long as the constraints above hold.
 
 The <dfn method for=CSSStyleDeclaration>removeProperty(<var>property</var>)</dfn> method must run these steps:
 <ol>
- <li>If the <a for="CSSStyleDeclaration">readonly flag</a> is set,
+ <li>If the <a for="CSSStyleDeclaration">computed flag</a> is set,
  then <a>throw</a> a {{NoModificationAllowedError}} exception.
  <li>If <var>property</var> is not a <a>custom property</a>,
  let <var>property</var> be <var>property</var> <a lt="ASCII lowercase">converted to ASCII lowercase</a>.
@@ -2801,7 +2804,7 @@ interface mixin ElementCSSInlineStyle {
 </pre>
 
 The <dfn attribute for=ElementCSSInlineStyle>style</dfn> attribute must return a <a>CSS declaration block</a> object whose
-<a for="CSSStyleDeclaration">readonly flag</a> is unset, whose <a for="CSSStyleDeclaration">parent CSS rule</a> is null, and
+<a for="CSSStyleDeclaration">computed flag</a> is unset, whose <a for="CSSStyleDeclaration">parent CSS rule</a> is null, and
 whose <a for="CSSStyleDeclaration">owner node</a> is the <a>context object</a>.
 
 If the user agent supports HTML, the following IDL applies: [[HTML]]
@@ -2859,7 +2862,7 @@ steps:
  <li>
   Return a live <a>CSS declaration block</a> with the following properties:
   <dl>
-   <dt><a for="CSSStyleDeclaration">readonly flag</a>
+   <dt><a for="CSSStyleDeclaration">computed flag</a>
    <dd>Set.
    <dt><a for="CSSStyleDeclaration">declarations</a>
    <dd><var>decls</var>.

-Original file line number
+Diff line change
 The style attribute must return a CSSStyleDeclaration object for the style rule, with the
 following properties:
 - readonly flag
 + computed flag
  Unset.
  declarations
  The declared declarations in the rule, in specified order.
 The style attribute must return a CSSStyleDeclaration object for the
 @page at-rule, with the following properties:
 - readonly flag
 + computed flag
  Unset.
  declarations
  The declared declarations in the rule, in specified order.
 The style attribute must return a CSSStyleDeclaration object for the
 margin at-rule, with the following properties:
 - readonly flag
 + computed flag
  Unset.
  declarations
  The declared declarations in the rule, in specified order.
 CSS declaration block has the following associated properties:
 - readonly flag
 - Unset if the object can be manipulated. Set if it can not be
 - manipulated. Unless otherwise stated it is unset.
 + computed flag
 + Set if the object is a computed style declaration, rather than a specified
 +     style. Unless otherwise stated it is unset.
  declarations
  The CSS declarations associated with the object.
 with localName, value, and namespace:
 - If the readonly flag is set, then return.
 + If the computed flag is set, then return.
  If the updating flag is set, then return.
  If localName is not "style", or namespace is not null, then return.
  If value is null, empty the declarations.
  Let owner node be the owner node.
 - If owner node is null, or the readonly flag is set, then return.
 + If owner node is null, or the computed flag is set, then return.
  Let value be the result of getting an attribute
  given null, "style", and owner node.
  If value is not null, let the declarations be the result of
 To update style attribute for declaration block means to run the steps below:
 - Assert: declaration block's readonly flag is unset.
 + Assert: declaration block's computed flag is unset.
  Let owner node be declaration block's owner node.
  If owner node is null, then return.
  Set declaration block's updating flag.
 CSS declarations in the declarations. If there are no such
 CSS declarations, then there are no supported property indices.
 -The cssText attribute must return the result of
 -serializing the declarations.
 +Getting the cssText attribute must run these steps:
++
 +1. If the computed flag is set, then return the empty string.
 +2. Return the result of serializing the declarations.
++
 Setting the {{CSSStyleDeclaration/cssText}} attribute must run these steps:
 - If the readonly flag is set,
 + If the computed flag is set,
  then throw a {{NoModificationAllowedError}} exception.
  Empty the declarations.
  Parse the given value and, if the return value is not the empty list, insert the items in the list
 The setProperty(property, value, priority) method must run these steps:
 - If the readonly flag is set,
 + If the computed flag is set,
  then throw a {{NoModificationAllowedError}} exception.
  If property is not a custom property, follow these substeps:
 The removeProperty(property) method must run these steps:
 - If the readonly flag is set,
 + If the computed flag is set,
  then throw a {{NoModificationAllowedError}} exception.
  If property is not a custom property,
  let property be property converted to ASCII lowercase.
 The style attribute must return a CSS declaration block object whose
 -readonly flag is unset, whose parent CSS rule is null, and
 +computed flag is unset, whose parent CSS rule is null, and
 whose owner node is the context object.
 If the user agent supports HTML, the following IDL applies: [[HTML]]
   Return a live CSS declaration block with the following properties:
 -   readonly flag
 +   computed flag
    Set.
    declarations
    decls.