Support the <slot> tag (#848)

* Support the <slot> tag

<slot> was added to the WHATWG HTML5 Living Standard on April 20, 2016.

* Also support the slot= attribute

Given that the <slot> tag by itself is not too useful, this commit also
introduces support for the global slot attribute.

* Using ParseBlock for <slot>

This is still suboptimal since ParseBlock will make it so that <slot>
always expects "Flow content", whereas the spec says that it should
have a Transparent content model.

In practice, it should allow all the cases that the spec allows for, but
it will also allow some cases that the spec does not allow. Notably, if
a <slot> tag is found in a Phrasing content (an inline context in
libtidy lingo), it will wrongly let Flow content (block tags in libtidy
lingo), whereas it shouldn't. But all in all, it's a good compromise.

Author: lhchavez

include/tidyenum.h

@@ -988,6 +988,7 @@ typedef enum
   TidyTag_OUTPUT,        /**< OUTPUT */
   TidyTag_PROGRESS,      /**< PROGRESS */
   TidyTag_SECTION,       /**< SECTION */
+  TidyTag_SLOT,          /**< SLOT */
   TidyTag_SOURCE,        /**< SOURCE */
   TidyTag_SUMMARY,       /**< SUMMARY */
   TidyTag_TEMPLATE,      /**< TEMPLATE */
@@ -1143,6 +1144,7 @@ typedef enum
   TidyAttr_SHOWGRIDX,              /**< SHOWGRIDX= */
   TidyAttr_SHOWGRIDY,              /**< SHOWGRIDY= */
   TidyAttr_SIZE,                   /**< SIZE= */
+  TidyAttr_SLOT,                   /**< SLOT= */
   TidyAttr_SPAN,                   /**< SPAN= */
   TidyAttr_SRC,                    /**< SRC= */
   TidyAttr_SRCSET,                 /**< SRCSET= (HTML5) */

src/attrdict.c

@@ -95,6 +95,7 @@
   { TidyAttr_IS,                    xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|HT50|XH50 }, \
   { TidyAttr_LANG,                  xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|HT50|XH50 }, \
   { TidyAttr_ROLE,                  xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|HT50|XH50 }, \
+  { TidyAttr_SLOT,                  xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|HT50|XH50 }, \
   { TidyAttr_SPELLCHECK,            xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|HT50|XH50 }, \
   { TidyAttr_STYLE,                 xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|HT50|XH50 }, \
   { TidyAttr_TABINDEX,              xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|HT50|XH50 }, \
@@ -2880,6 +2881,17 @@ const AttrVersion TY_(W3CAttrsFor_SMALL)[] =
   { TidyAttr_UNKNOWN,               0                                                                          },
 };
 
+const AttrVersion TY_(W3CAttrsFor_SLOT)[] =
+{
+  INCLUDE_ARIA
+  INCLUDE_MICRODATA
+  { TidyAttr_NAME,                  xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|HT50|XH50 },
+  INCLUDE_CORE_ATTRIBS
+  INCLUDE_CORE_EVENTS
+  INCLUDE_RDFA
+  { TidyAttr_UNKNOWN,               0                                                                          },
+};
+
 const AttrVersion TY_(W3CAttrsFor_SOURCE)[] = 
 {
   INCLUDE_ARIA

src/attrdict.h

@@ -142,6 +142,7 @@ extern const AttrVersion TY_(W3CAttrsFor_OUTPUT)[];
 extern const AttrVersion TY_(W3CAttrsFor_MENUITEM)[];
 extern const AttrVersion TY_(W3CAttrsFor_METER)[];
 extern const AttrVersion TY_(W3CAttrsFor_PROGRESS)[];
+extern const AttrVersion TY_(W3CAttrsFor_SLOT)[];
 extern const AttrVersion TY_(W3CAttrsFor_TEMPLATE)[];
 extern const AttrVersion TY_(W3CAttrsFor_TIME)[];
 extern const AttrVersion TY_(W3CAttrsFor_DATA)[];

src/attrs.c

@@ -238,6 +238,7 @@ static const Attribute attribute_defs [] =
   { TidyAttr_SHOWGRIDX,               "showgridx",               CH_BOOL      }, /* TABLE Adobe golive*/
   { TidyAttr_SHOWGRIDY,               "showgridy",               CH_BOOL      }, /* TABLE Adobe golive*/
   { TidyAttr_SIZE,                    "size",                    CH_NUMBER    }, /* HR, FONT, BASEFONT, SELECT */
+  { TidyAttr_SLOT,                    "slot",                    CH_PCDATA    },
   { TidyAttr_SPAN,                    "span",                    CH_NUMBER    }, /* COL, COLGROUP */
   { TidyAttr_SRC,                     "src",                     CH_URL       }, /* IMG, FRAME, IFRAME */
   { TidyAttr_SRCSET,                  "srcset",                  CH_PCDATA    }, /* IMG (HTML5) */

src/attrs.h

@@ -315,6 +315,7 @@ Bool TY_(AttributeIsMismatched)(Node* node, AttVal* attval, TidyDocImpl* doc);
 #define attrIsSHOWGRIDX(av)         AttrIsId( av, TidyAttr_SHOWGRIDX  )
 #define attrIsSHOWGRIDY(av)         AttrIsId( av, TidyAttr_SHOWGRIDY  )
 #define attrIsSIZE(av)              AttrIsId( av, TidyAttr_SIZE  )
+#define attrIsSLOT(av)              AttrIsId( av, TidyAttr_SLOT  )
 #define attrIsSPAN(av)              AttrIsId( av, TidyAttr_SPAN  )
 #define attrIsSRC(av)               AttrIsId( av, TidyAttr_SRC  )
 #define attrIsSTANDBY(av)           AttrIsId( av, TidyAttr_STANDBY  )

src/tags.c

@@ -151,6 +151,7 @@ static CheckAttribs CheckHTML;
 #define VERS_ELEM_OUTPUT     (xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|HT50|XH50)
 #define VERS_ELEM_PROGRESS   (xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|HT50|XH50)
 #define VERS_ELEM_SECTION    (xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|HT50|XH50)
+#define VERS_ELEM_SLOT       (xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|HT50|XH50)
 #define VERS_ELEM_SOURCE     (xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|HT50|XH50)
 #define VERS_ELEM_SUMMARY    (xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|HT50|XH50)
 #define VERS_ELEM_TEMPLATE   (xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|xxxx|HT50|XH50)
@@ -321,6 +322,7 @@ static Dict tag_defs[] =
   { TidyTag_OUTPUT,      "output",       VERS_ELEM_OUTPUT,      &TY_(W3CAttrsFor_OUTPUT)[0],      (CM_INLINE),                   TY_(ParseInline),    NULL           },
   { TidyTag_PROGRESS,    "progress",     VERS_ELEM_PROGRESS,    &TY_(W3CAttrsFor_PROGRESS)[0],    (CM_INLINE),                   TY_(ParseInline),    NULL           },
   { TidyTag_SECTION,     "section",      VERS_ELEM_SECTION,     &TY_(W3CAttrsFor_SECTION)[0],     (CM_BLOCK),                    TY_(ParseBlock),     NULL           },
+  { TidyTag_SLOT,        "slot",         VERS_ELEM_SLOT,        &TY_(W3CAttrsFor_SLOT)[0],        (CM_BLOCK|CM_INLINE|CM_MIXED), TY_(ParseBlock),     NULL           },
   { TidyTag_SOURCE,      "source",       VERS_ELEM_SOURCE,      &TY_(W3CAttrsFor_SOURCE)[0],      (CM_BLOCK|CM_INLINE|CM_EMPTY), TY_(ParseBlock),     NULL           },
   { TidyTag_SUMMARY,     "summary",      VERS_ELEM_SUMMARY,     &TY_(W3CAttrsFor_SUMMARY)[0],     (CM_BLOCK),                    TY_(ParseBlock),     NULL           }, /* Is. #895 */
   { TidyTag_TEMPLATE,    "template",     VERS_ELEM_TEMPLATE,    &TY_(W3CAttrsFor_TEMPLATE)[0],    (CM_BLOCK),                    TY_(ParseBlock),     NULL           },