[PATCH v2 03/13] emacs: make "+" and "-" tagging operations in notmuch-search more robust

[Austin Clements]

Looking good.  Just a few small points below.

Quoth Dmitry Kurochkin on Jan 30 at  6:26 am:
> Before the change, "+" and "-" tagging operations in notmuch-search
> view accepted only a single tag.  The patch makes them use the
> recently added `notmuch-read-tag-changes' function (renamed
> `notmuch-select-tags-with-completion'), which allows to enter multiple
> tags with "+" and "-" prefixes.  So after the change, "+" and "-"
> bindings in notmuch-search view allow to both add and remove multiple
> tags.  The only difference between "+" and "-" is the minibuffer
> initial input ("+" and "-" respectively).
> ---
>  emacs/notmuch.el |  164 +++++++++++++++++++++++++++---------------------------
>  1 files changed, 82 insertions(+), 82 deletions(-)
> 
> diff --git a/emacs/notmuch.el b/emacs/notmuch.el
> index ff46617..90b594c 100644
> --- a/emacs/notmuch.el
> +++ b/emacs/notmuch.el
> @@ -76,38 +76,57 @@ For example:
>  (defvar notmuch-query-history nil
>    "Variable to store minibuffer history for notmuch queries")
>  
> -(defun notmuch-tag-completions (&optional prefixes search-terms)
> -  (let ((tag-list
> -	 (split-string
> -	  (with-output-to-string
> -	    (with-current-buffer standard-output
> -	      (apply 'call-process notmuch-command nil t
> -		     nil "search-tags" search-terms)))
> -	  "\n+" t)))
> -    (if (null prefixes)
> -	tag-list
> -      (apply #'append
> -	     (mapcar (lambda (tag)
> -		       (mapcar (lambda (prefix)
> -				 (concat prefix tag)) prefixes))
> -		     tag-list)))))
> +(defun notmuch-tag-completions (&optional search-terms)
> +  (split-string
> +   (with-output-to-string
> +     (with-current-buffer standard-output
> +       (apply 'call-process notmuch-command nil t
> +	      nil "search-tags" search-terms)))
> +   "\n+" t))
>  
>  (defun notmuch-select-tag-with-completion (prompt &rest search-terms)
> -  (let ((tag-list (notmuch-tag-completions nil search-terms)))
> +  (let ((tag-list (notmuch-tag-completions search-terms)))
>      (completing-read prompt tag-list)))
>  
> -(defun notmuch-select-tags-with-completion (prompt &optional prefixes &rest search-terms)
> -  (let ((tag-list (notmuch-tag-completions prefixes search-terms))
> -	(crm-separator " ")
> -	;; By default, space is bound to "complete word" function.
> -	;; Re-bind it to insert a space instead.  Note that <tab>
> -	;; still does the completion.
> -	(crm-local-completion-map
> -	 (let ((map (make-sparse-keymap)))
> -	   (set-keymap-parent map crm-local-completion-map)
> -	   (define-key map " " 'self-insert-command)
> -	   map)))
> -    (delete "" (completing-read-multiple prompt tag-list))))
> +(defun notmuch-read-tag-changes (&optional initial-input &rest search-terms)
> +  (let* ((all-tag-list (notmuch-tag-completions))
> +	 (add-tag-list (mapcar (apply-partially 'concat "+") all-tag-list))
> +	 (remove-tag-list (mapcar (apply-partially 'concat "-")
> +				  (if (null search-terms)
> +				      all-tag-list
> +				    (notmuch-tag-completions search-terms))))
> +	 (tag-list (append add-tag-list remove-tag-list))
> +	 (crm-separator " ")
> +	 ;; By default, space is bound to "complete word" function.
> +	 ;; Re-bind it to insert a space instead.  Note that <tab>
> +	 ;; still does the completion.
> +	 (crm-local-completion-map
> +	  (let ((map (make-sparse-keymap)))
> +	    (set-keymap-parent map crm-local-completion-map)
> +	    (define-key map " " 'self-insert-command)
> +	    map)))
> +    (delete "" (completing-read-multiple "Tags (+add -drop): "
> +		tag-list nil nil initial-input))))
> +
> +(defun notmuch-update-tags (tags tag-changes)
> +  "Return a copy of TAGS with additions and removals from TAG-CHANGES.
> +
> +TAG-CHANGES must be a list of tags names, each prefixed with
> +either a \"+\" to indicate the tag should be added to TAGS if not
> +present or a \"-\" to indicate that the tag should be removed
> +from TAGS if present."
> +  (let ((result-tags (copy-sequence tags)))
> +    (dolist (tag-change tag-changes)
> +      (unless (string= tag-change "")

This function should give the "must be of the form" error for empty
strings, rather than silently ignoring them.  It turns out
`string-to-char' on an empty string is fine (it returns 0, which will
trigger the error), but `substring' isn't.  Perhaps move the unless
into the let before, like
 (let ((op (string-to-char tag-change))
       (tag (unless (string= tag-change "") (substring tag-change 1))))

> +	(let ((op (string-to-char tag-change))
> +	      (tag (substring tag-change 1)))
> +	  (case op
> +	    (?+ (unless (member tag result-tags)
> +		  (push tag result-tags)))
> +	    (?- (setq result-tags (delete tag result-tags)))
> +	    (otherwise
> +	     (error "Changed tag must be of the form `+this_tag' or `-that_tag'"))))))
> +    (sort result-tags 'string<)))
>  
>  (defun notmuch-foreach-mime-part (function mm-handle)
>    (cond ((stringp (car mm-handle))
> @@ -447,6 +466,10 @@ Complete list of currently available key bindings:
>    "Return a list of threads for the current region"
>    (notmuch-search-properties-in-region 'notmuch-search-thread-id beg end))
>  
> +(defun notmuch-search-find-thread-id-region-search (beg end)
> +  "Return a search string for threads for the current region"
> +  (mapconcat 'identity (notmuch-search-find-thread-id-region beg end) " or "))
> +
>  (defun notmuch-search-find-authors ()
>    "Return the authors for the current thread"
>    (get-text-property (point) 'notmuch-search-authors))
> @@ -590,74 +613,53 @@ the messages that were tagged"
>  	(forward-line 1))
>        output)))
>  
> -(defun notmuch-search-add-tag-thread (tag)
> -  (notmuch-search-add-tag-region tag (point) (point)))
> +(defun notmuch-search-tag-thread (&rest tags)

Maybe "tag-changes" instead of "tags" for this and
notmuch-search-tag-region?

> +  "Change tags for the currently selected thread.
>  
> -(defun notmuch-search-add-tag-region (tag beg end)
> -  (let ((search-id-string (mapconcat 'identity (notmuch-search-find-thread-id-region beg end) " or ")))
> -    (notmuch-tag search-id-string (concat "+" tag))
> -    (save-excursion
> -      (let ((last-line (line-number-at-pos end))
> -	    (max-line (- (line-number-at-pos (point-max)) 2)))
> -	(goto-char beg)
> -	(while (<= (line-number-at-pos) (min last-line max-line))
> -	  (notmuch-search-set-tags (delete-dups (sort (cons tag (notmuch-search-get-tags)) 'string<)))
> -	  (forward-line))))))
> +See `notmuch-search-tag-region' for details."
> +  (apply 'notmuch-search-tag-region (point) (point) tags))
>  
> -(defun notmuch-search-remove-tag-thread (tag)
> -  (notmuch-search-remove-tag-region tag (point) (point)))
> +(defun notmuch-search-tag-region (beg end &rest tags)
> +  "Change tags for threads in the given region.
>  
> -(defun notmuch-search-remove-tag-region (tag beg end)
> -  (let ((search-id-string (mapconcat 'identity (notmuch-search-find-thread-id-region beg end) " or ")))
> -    (notmuch-tag search-id-string (concat "-" tag))
> +TAGS is a list of tag operations for `notmuch-tag'.  The tags are
> +added or removed for all threads in the region from BEG to END."
> +  (let ((search-string (notmuch-search-find-thread-id-region-search beg end)))
> +    (apply 'notmuch-tag search-string tags)
>      (save-excursion
>        (let ((last-line (line-number-at-pos end))
>  	    (max-line (- (line-number-at-pos (point-max)) 2)))
>  	(goto-char beg)
>  	(while (<= (line-number-at-pos) (min last-line max-line))
> -	  (notmuch-search-set-tags (delete tag (notmuch-search-get-tags)))
> +	  (notmuch-search-set-tags
> +	   (notmuch-update-tags (notmuch-search-get-tags) tags))
>  	  (forward-line))))))
>  
> -(defun notmuch-search-add-tag (tag)
> -  "Add a tag to the currently selected thread or region.
> -
> -The tag is added to all messages in the currently selected thread
> -or threads in the current region."
> -  (interactive
> -   (list (notmuch-select-tag-with-completion "Tag to add: ")))
> -  (save-excursion
> -    (if (region-active-p)
> -	(let* ((beg (region-beginning))
> -	       (end (region-end)))
> -	  (notmuch-search-add-tag-region tag beg end))
> -      (notmuch-search-add-tag-thread tag))))
> -
> -(defun notmuch-search-remove-tag (tag)
> -  "Remove a tag from the currently selected thread or region.

It's great to see all of this old copy-pasted code go away!

> +(defun notmuch-search-tag (&optional initial-input)
> +  "Change tags for the currently selected thread or region."
> +  (interactive)
> +  (let* ((beg (if (region-active-p) (region-beginning) (point)))
> +	 (end (if (region-active-p) (region-end) (point)))
> +	 (search-string (notmuch-search-find-thread-id-region-search beg end))
> +	 (tags (notmuch-read-tag-changes initial-input search-string)))
> +    (apply 'notmuch-search-tag-region beg end tags)))
> +
> +(defun notmuch-search-add-tag ()
> +  "Same as `notmuch-search-tag' but sets initial input to '+'."
> +  (interactive)
> +  (notmuch-search-tag "+"))
>  
> -The tag is removed from all messages in the currently selected
> -thread or threads in the current region."
> -  (interactive
> -   (list (notmuch-select-tag-with-completion
> -	  "Tag to remove: "
> -	  (if (region-active-p)
> -	      (mapconcat 'identity
> -			 (notmuch-search-find-thread-id-region (region-beginning) (region-end))
> -			 " ")
> -	    (notmuch-search-find-thread-id)))))
> -  (save-excursion
> -    (if (region-active-p)
> -	(let* ((beg (region-beginning))
> -	       (end (region-end)))
> -	  (notmuch-search-remove-tag-region tag beg end))
> -      (notmuch-search-remove-tag-thread tag))))
> +(defun notmuch-search-remove-tag ()
> +  "Same as `notmuch-search-tag' but sets initial input to '-'."
> +  (interactive)
> +  (notmuch-search-tag "-"))
>  
>  (defun notmuch-search-archive-thread ()
>    "Archive the currently selected thread (remove its \"inbox\" tag).
>  
>  This function advances the next thread when finished."
>    (interactive)
> -  (notmuch-search-remove-tag-thread "inbox")
> +  (notmuch-search-tag-thread "-inbox")
>    (notmuch-search-next-thread))
>  
>  (defvar notmuch-search-process-filter-data nil
> @@ -893,9 +895,7 @@ will prompt for tags to be added or removed. Tags prefixed with
>  Each character of the tag name may consist of alphanumeric
>  characters as well as `_.+-'.
>  "
> -  (interactive (notmuch-select-tags-with-completion
> -		"Operations (+add -drop): notmuch tag "
> -		'("+" "-")))
> +  (interactive (notmuch-read-tag-changes))
>    (apply 'notmuch-tag notmuch-search-query-string actions))
>  
>  (defun notmuch-search-buffer-title (query)