In the attached file "test.org", I want to capture new headings above
"Projects" always.  To achieve this, I used a file+function target to
move the point above "Projects" like below

    (let* ((heading "test")
           (file "tttt.pdf")
           (org-capture-templates
        `(("n" "blah"
               entry
               (file+function "/tmp/test.org"
                              ,(lambda ()
                     (goto-char (point-min))
                     (re-search-forward "^\\* Projects")
                     (goto-char (match-beginning 0))
                     (insert "\n")
                     (forward-char -1)))
           ,(concat "* " heading "\n"
                ":PROPERTIES:\n"
                ":NOTER_DOCUMENT: " file "\n"
                ":END:\n\n")
           :immediate-finish t
           :empty-lines-before 1))))
      (org-capture nil "n"))

However, when evaluating this sexp, the heading "test" is always
appended to the end of file contrary to what the docstring says:

    (file+function "path/to/file" function-finding-location)
        A function to find the right location in the file

This is because of the 'else' clause in the cond form in
org-capture-place-entry:

    (when exact-position (goto-char exact-position))
    (cond
     ;; Force insertion at point.
     (insert-here?
      ....)
     ;; Insert as a child of the current entry.
     ((org-capture-get :target-entry-p)
      ...)
     ;; Insert as a top-level entry at the beginning of the file.
     (reversed?
      ...)
     ;; Otherwise, insert as a top-level entry at the end of the file.
     (t (goto-char (point-max))
        ^^^^^^^^^^^^^^^^^^^^^^^
        ;; Make sure that last point is not folded.
        (org-fold-core-cycle-over-indirect-buffers
          (org-fold-region (max 1 (1- (point-max))) (point-max) nil))))

Should this be here?  Am I misunderstanding the documentation?  After
all, it is too terse (the same text is in the Info manual too).  The
documentation for the 'entry' type does not mention this quirk either:

    entry       an Org node, with a headline.  Will be filed
                as the child of the target entry or as a  
                top-level entry.  Its default template is:
                  "* %?\n%a"

The documentation for :prepend does mention that entries will be
inserted at the end if it is nil but I would think that using a function
would rule this out.

Changing the type to 'plain' from 'entry' works as expected though.