the_excerpt() - <!--more--> handling

[wpweaver]

If a post has a manually inserted <!--more--> before the default break at the excerpt length, then the_excerpt() fails to generate any [...] or call the "excerpt_more" filter. Thus, there is no indication that there is more content to the post.

[kawauso]

The issue can be traced back to using get_the_content() in wp_trim_excerpt() which cuts off at <!--more--> regardless of the caller function and doesn't have a more text provided for it.

Following patch splices in a minimal version of the_content() rather than trying to bend the existing code or use a hacky workaround such as $more = 1

Cut:

• <!--noteaser--> checks which sets $stripteaser: isn't used unless $more is true

• if ( count($content) > 1 ): only invokes force_balance_tags() since $more is false and $more_link_text is empty, which is unnecessary since we strip_tags()

Not cut:

• post_password_required() check, though it's overridden by the_excerpt()

• $preview check: is this needed?

[kawauso]

wp_trim_excerpt() isn't fired if post_password_required() is true, so drop internal check

[kawauso]

Last patch does have the slight difference that if it's called by a function other than get_the_excerpt() that fails to replicate the password required check, it will return the actual excerpt rather than a mangled excerptified password form.

[nacin]

This was noticed during Twenty Ten development. See #13361 for relevant conversation.

[nacin]

See also #25349, somewhat related to the weirdness here.