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Merged
dnouri merged 1 commit into from
Mar 18, 2026
Merged

Display tables with box-drawing characters #173

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88 changes: 53 additions & 35 deletions pi-coding-agent-table.el
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Original file line number Diff line number Diff line change
Expand Up @@ -246,41 +246,52 @@ Returns (PREFIX . BARE), where PREFIX is everything before the first `|'."
(md-ts--set-hide-markup t)))
pi-coding-agent--visible-string-buffer)

(defconst pi-coding-agent--markdown-inline-chars-re "[*_`~\\[]"
"Regexp matching characters that can start markdown inline syntax.
Cells without any of these characters have identical visible rendering
and can skip the fontification buffer entirely.")

(defun pi-coding-agent--markdown-visible-string (markdown)
"Return the visible chat-buffer rendering of MARKDOWN.
This hides markdown delimiters the same way `pi-coding-agent-chat-mode'
does, so wrapped table overlays match ordinary visible-copy semantics.
Uses a persistent fontification buffer to avoid per-call mode setup."
(with-current-buffer (pi-coding-agent--visible-string-buffer)
(let ((inhibit-read-only t))
(erase-buffer)
(insert markdown))
(font-lock-ensure)
(pi-coding-agent--visible-text (point-min) (point-max))))
Uses a persistent fontification buffer to avoid per-call mode setup.
Cells with no inline syntax characters are returned as-is."
(if (not (string-match-p pi-coding-agent--markdown-inline-chars-re markdown))
markdown
(with-current-buffer (pi-coding-agent--visible-string-buffer)
(let ((inhibit-read-only t))
(erase-buffer)
(insert markdown))
(font-lock-ensure)
(pi-coding-agent--visible-text (point-min) (point-max)))))

;;;; Cell Rendering

(defun pi-coding-agent--render-table-row-lines (cells col-widths aligns)
"Render table CELLS into display lines using COL-WIDTHS and ALIGNS.
Builds each line with a flat string accumulator to reduce intermediate
consing: padding and cell fragments are pushed individually, then
joined with a single `apply concat'."
When `pi-coding-agent-prettify-tables' is non-nil, emits Unicode
box-drawing verticals instead of markdown pipes."
(let* ((num-cols (length col-widths))
(padded (append cells (make-list (max 0 (- num-cols (length cells))) "")))
(wrapped-cells
(cl-mapcar (lambda (cell column-width)
(markdown-table-wrap-cell (or cell "") column-width))
padded col-widths))
(max-height (apply #'max (mapcar #'length wrapped-cells))))
(max-height (apply #'max (mapcar #'length wrapped-cells)))
(pretty pi-coding-agent-prettify-tables)
(delim-open (if pretty "│ " "| "))
(delim-mid (if pretty " │ " " | "))
(delim-close (if pretty " │" " |")))
(cl-loop for line-index below max-height
collect
(let ((acc (list "| ")))
(let ((acc (list delim-open)))
(cl-loop for cell-lines in wrapped-cells
for column-width in col-widths
for align in aligns
for first = t then nil
do
(unless first (push " | " acc))
(unless first (push delim-mid acc))
(let* ((cell (or (nth line-index cell-lines) ""))
(empty (string-empty-p cell))
(pad (if empty
Expand All @@ -301,31 +312,37 @@ joined with a single `apply concat'."
(t
(push cell acc)
(push (make-string pad ?\s) acc)))))
(push " |" acc)
(push delim-close acc)
(apply #'concat (nreverse acc))))))

(defun pi-coding-agent--render-table-separator-line (col-widths aligns)
"Render the markdown separator line for COL-WIDTHS and ALIGNS."
(let ((parts
(cl-mapcar
(lambda (column-width align)
(let ((dashes (make-string (max 1 column-width) ?-)))
(pcase align
('left
(if (>= column-width 2)
(concat ":" (substring dashes 1))
":"))
('right
(if (>= column-width 2)
(concat (substring dashes 1) ":")
":"))
('center
(if (>= column-width 3)
(concat ":" (substring dashes 2) ":")
(if (>= column-width 2) "::" ":")))
(_ dashes))))
col-widths aligns)))
(concat "| " (mapconcat #'identity parts " | ") " |")))
"Render the separator line for COL-WIDTHS and ALIGNS.
When `pi-coding-agent-prettify-tables' is non-nil, emits a box-drawing
rule (├─┼─┤) directly; otherwise emits standard markdown syntax."
(if pi-coding-agent-prettify-tables
(concat "├─" (mapconcat (lambda (w) (make-string (max 1 w) ?─))
col-widths "─┼─")
"─┤")
(let ((parts
(cl-mapcar
(lambda (column-width align)
(let ((dashes (make-string (max 1 column-width) ?-)))
(pcase align
('left
(if (>= column-width 2)
(concat ":" (substring dashes 1))
":"))
('right
(if (>= column-width 2)
(concat (substring dashes 1) ":")
":"))
('center
(if (>= column-width 3)
(concat ":" (substring dashes 2) ":")
(if (>= column-width 2) "::" ":")))
(_ dashes))))
col-widths aligns)))
(concat "| " (mapconcat #'identity parts " | ") " |"))))

(defun pi-coding-agent--table-alignments (separator-line)
"Return column alignment symbols parsed from SEPARATOR-LINE."
Expand Down Expand Up @@ -560,6 +577,7 @@ blank-line spacing between a table and following text is not collapsed."
(ov (make-overlay line-beg line-end nil nil nil)))
(overlay-put ov 'display
(pi-coding-agent--neutralize-fonts display-str))
(overlay-put ov 'face 'default)
(overlay-put ov 'pi-coding-agent-table-display t)
(overlay-put ov 'evaporate t))
(forward-line 1))))
Expand Down
9 changes: 9 additions & 0 deletions pi-coding-agent-ui.el
View file
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Original file line number Diff line number Diff line change
Expand Up @@ -174,6 +174,15 @@ inside that suffix; older history stays frozen until explicitly rebuilt."
:type 'natnum
:group 'pi-coding-agent)

(defcustom pi-coding-agent-prettify-tables t
"Whether display-only markdown tables use prettier visible separators.
When non-nil, table overlays replace raw markdown pipes and separator rows
with Unicode box-drawing characters in the visible display. The underlying
buffer text stays canonical markdown, so copy, search, and session history
still operate on the raw table source."
:type 'boolean
:group 'pi-coding-agent)

;;;; Faces

(defface pi-coding-agent-timestamp
Expand Down
79 changes: 79 additions & 0 deletions test/pi-coding-agent-table-test.el
View file
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Original file line number Diff line number Diff line change
Expand Up @@ -379,6 +379,76 @@ so visible text still needs consistent alignment across all display lines."
(let ((widths (mapcar #'string-width (nreverse all-lines))))
(should (= (length (delete-dups (copy-sequence widths))) 1))))))

(ert-deftest pi-coding-agent-test-decorate-table-prettifies-visible-separators ()
"Rendered table display uses box-drawing separators instead of raw pipes."
(with-temp-buffer
(pi-coding-agent-chat-mode)
(let ((inhibit-read-only t))
(insert "| Name | Value |\n|------|-------|\n| Alpha | Beta |\n"))
(font-lock-ensure)
(pi-coding-agent--decorate-tables-in-region (point-min) (point-max) 40)
(let ((all-display (mapconcat #'identity
(pi-coding-agent-test--table-overlay-displays-in-region
(point-min) (point-max))
"\n")))
;; Rows use box-drawing verticals, not raw markdown pipes
(should (string-match-p "^│ " all-display))
(should-not (string-match-p "^| " all-display))
;; Separator uses box-drawing horizontals
(should (string-match-p "├.*┼.*┤" all-display))
;; Table content preserved
(should (string-match-p "Name" all-display))
(should (string-match-p "Alpha" all-display)))))

(ert-deftest pi-coding-agent-test-decorate-table-preserves-pipes-when-prettify-off ()
"With prettify disabled, rendered tables use standard markdown pipes."
(with-temp-buffer
(pi-coding-agent-chat-mode)
(let ((pi-coding-agent-prettify-tables nil)
(inhibit-read-only t))
(insert "| Name | Value |\n|------|-------|\n| Alpha | Beta |\n")
(font-lock-ensure)
(pi-coding-agent--decorate-tables-in-region (point-min) (point-max) 40)
(let ((all-display (mapconcat #'identity
(pi-coding-agent-test--table-overlay-displays-in-region
(point-min) (point-max))
"\n")))
;; Standard markdown pipe delimiters
(should (string-match-p "^| " all-display))
;; No box-drawing characters
(should-not (string-match-p "│" all-display))
(should-not (string-match-p "├" all-display))
;; Separator uses dashes
(should (string-match-p "---" all-display))
;; Table content preserved
(should (string-match-p "Name" all-display))
(should (string-match-p "Alpha" all-display))))))

(ert-deftest pi-coding-agent-test-table-overlay-suppresses-buffer-face ()
"Table overlays suppress tree-sitter buffer faces without losing inline formatting.
Tree-sitter applies `md-ts-delimiter' (shadow) to separator rows and `bold'
to headers. The overlay must suppress these while preserving inline markdown
formatting (bold, italic) in the display string's text properties."
(with-temp-buffer
(pi-coding-agent-chat-mode)
(let ((inhibit-read-only t))
(insert "| Name | Note |\n|------|------|\n| **bold** | text |\n"))
(font-lock-ensure)
(pi-coding-agent--decorate-tables-in-region (point-min) (point-max) 40)
(let ((ovs (sort (seq-filter
(lambda (ov) (overlay-get ov 'pi-coding-agent-table-display))
(overlays-in (point-min) (point-max)))
(lambda (a b) (< (overlay-start a) (overlay-start b))))))
;; Every overlay has an explicit face to block buffer face bleed-through
(should (cl-every (lambda (ov) (overlay-get ov 'face)) ovs))
;; Separator overlay does not inherit shadow
(let ((sep-face (overlay-get (nth 1 ovs) 'face)))
(should-not (eq sep-face 'md-ts-delimiter))
(should-not (eq sep-face 'shadow)))
;; Inline bold from **bold** survives in the data row display string
(should (pi-coding-agent-test--string-has-face-attr-p
(overlay-get (nth 2 ovs) 'display) :weight 'bold)))))

(ert-deftest pi-coding-agent-test-decorate-table-hides-inline-markup-in-display ()
"Wrapped table display hides markdown delimiters like the chat buffer does."
(with-temp-buffer
Expand Down Expand Up @@ -515,6 +585,15 @@ what the parser recognizes as a `pipe_table'."
1))
(should (= (pi-coding-agent-test--table-overlay-count) 0))))

(defun pi-coding-agent-test--string-has-face-attr-p (str attr value)
"Return non-nil if STR has face ATTR equal to VALUE at any position."
(let ((pos 0)
(len (length str)))
(cl-loop while (< pos len)
for face = (get-text-property pos 'face str)
thereis (and (consp face) (eq (plist-get face attr) value))
do (setq pos (next-single-property-change pos 'face str len)))))

(defun pi-coding-agent-test--table-overlay-count ()
"Count table display overlays in the current buffer."
(length (seq-filter
Expand Down
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