; Add files missing in ab351d442d7scratch/org-mode-merge

4 files changed, 631 insertions, 114 deletions

diff --git a/lisp/org/ob-hledger.el b/lisp/org/ob-hledger.el
new file mode 100644
index 00000000000..86276aad810
--- /dev/null
+++ b/lisp/org/ob-hledger.el
@@ -0,0 +1,70 @@
+;;  ob-ledger.el --- Babel Functions for hledger      -*- lexical-binding: t; -*-
+
+;; Copyright (C) 2010-2017 Free Software Foundation, Inc.
+
+;; Author: Simon Michael
+;; Keywords: literate programming, reproducible research, plain text accounting
+;; Homepage: http://orgmode.org
+
+;; This file is part of GNU Emacs.
+
+;; GNU Emacs is free software: you can redistribute it and/or modify
+;; it under the terms of the GNU General Public License as published by
+;; the Free Software Foundation, either version 3 of the License, or
+;; (at your option) any later version.
+
+;; GNU Emacs is distributed in the hope that it will be useful,
+;; but WITHOUT ANY WARRANTY; without even the implied warranty of
+;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+;; GNU General Public License for more details.
+
+;; You should have received a copy of the GNU General Public License
+;; along with GNU Emacs.  If not, see <https://www.gnu.org/licenses/>.
+
+;;; Commentary:
+
+;; Babel support for evaluating hledger entries.
+;;
+;; Based on ob-ledger.el.
+;; If the source block is empty, hledger will use a default journal file,
+;; probably ~/.hledger.journal (it may not notice your $LEDGER_FILE env var).
+;; So make ~/.hledger.journal a symbolic link to the real file if necessary.
+
+;;; Code:
+(require 'ob)
+
+(defvar org-babel-default-header-args:hledger
+  '((:results . "output") (:exports . "results") (:cmdline . "bal"))
+  "Default arguments to use when evaluating a hledger source block.")
+
+(defun org-babel-execute:hledger (body params)
+  "Execute a block of hledger entries with org-babel.
+This function is called by `org-babel-execute-src-block'."
+  (message "executing hledger source code block")
+  (letrec ( ;(result-params (split-string (or (cdr (assq :results params)) "")))
+           (cmdline (cdr (assq :cmdline params)))
+           (in-file (org-babel-temp-file "hledger-"))
+           (out-file (org-babel-temp-file "hledger-output-"))
+           (hledgercmd (concat "hledger"
+                               (if (> (length body) 0)
+                                   (concat " -f " (org-babel-process-file-name in-file))
+                                 "")
+                               " " cmdline)))
+    (with-temp-file in-file (insert body))
+;; TODO This is calling for some refactoring:
+;;  (concat "hledger" (if ...) " " cmdline)
+;; could be built only once and bound to a symbol.
+    (message "%s" hledgercmd)
+    (with-output-to-string
+      (shell-command (concat hledgercmd " > " (org-babel-process-file-name out-file))))
+    (with-temp-buffer (insert-file-contents out-file) (buffer-string))))
+
+(defun org-babel-prep-session:hledger (_session _params)
+  (error "hledger does not support sessions"))
+
+(provide 'ob-hledger)
+
+
+
+;;; ob-hledger.el ends here
+;; TODO Unit tests are more than welcome, too.
diff --git a/lisp/org/ob-scala.el b/lisp/org/ob-scala.el
deleted file mode 100644
index d00b97c3db4..00000000000
--- a/lisp/org/ob-scala.el
+++ /dev/null
@@ -1,114 +0,0 @@
-;;; ob-scala.el --- Babel Functions for Scala        -*- lexical-binding: t; -*-
-
-;; Copyright (C) 2012-2017 Free Software Foundation, Inc.
-
-;; Author: Andrzej Lichnerowicz
-;; Keywords: literate programming, reproducible research
-;; Homepage: http://orgmode.org
-
-;; This file is part of GNU Emacs.
-
-;; GNU Emacs is free software: you can redistribute it and/or modify
-;; it under the terms of the GNU General Public License as published by
-;; the Free Software Foundation, either version 3 of the License, or
-;; (at your option) any later version.
-
-;; GNU Emacs is distributed in the hope that it will be useful,
-;; but WITHOUT ANY WARRANTY; without even the implied warranty of
-;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-;; GNU General Public License for more details.
-
-;; You should have received a copy of the GNU General Public License
-;; along with GNU Emacs.  If not, see <https://www.gnu.org/licenses/>.
-
-;;; Commentary:
-;; Currently only supports the external execution.  No session support yet.
-
-;;; Requirements:
-;; - Scala language :: http://www.scala-lang.org/
-;; - Scala major mode :: Can be installed from Scala sources
-;;  https://github.com/scala/scala-dist/blob/master/tool-support/src/emacs/scala-mode.el
-
-;;; Code:
-(require 'ob)
-
-(defvar org-babel-tangle-lang-exts) ;; Autoloaded
-(add-to-list 'org-babel-tangle-lang-exts '("scala" . "scala"))
-(defvar org-babel-default-header-args:scala '())
-(defvar org-babel-scala-command "scala"
-  "Name of the command to use for executing Scala code.")
-
-(defun org-babel-execute:scala (body params)
-  "Execute a block of Scala code with org-babel.  This function is
-called by `org-babel-execute-src-block'"
-  (message "executing Scala source code block")
-  (let* ((processed-params (org-babel-process-params params))
-         (session (org-babel-scala-initiate-session (nth 0 processed-params)))
-         (result-params (nth 2 processed-params))
-         (result-type (cdr (assq :result-type params)))
-         (full-body (org-babel-expand-body:generic
-                     body params))
-         (result (org-babel-scala-evaluate
-                  session full-body result-type result-params)))
-
-    (org-babel-reassemble-table
-     result
-     (org-babel-pick-name
-      (cdr (assq :colname-names params)) (cdr (assq :colnames params)))
-     (org-babel-pick-name
-      (cdr (assq :rowname-names params)) (cdr (assq :rownames params))))))
-
-(defvar org-babel-scala-wrapper-method
-
-"var str_result :String = null;
-
-Console.withOut(new java.io.OutputStream() {def write(b: Int){
-}}) {
-  str_result = {
-%s
-  }.toString
-}
-
-print(str_result)
-")
-
-
-(defun org-babel-scala-evaluate
-    (session body &optional result-type result-params)
-  "Evaluate BODY in external Scala process.
-If RESULT-TYPE equals `output' then return standard output as a string.
-If RESULT-TYPE equals `value' then return the value of the last statement
-in BODY as elisp."
-  (when session (error "Sessions are not (yet) supported for Scala"))
-  (pcase result-type
-    (`output
-     (let ((src-file (org-babel-temp-file "scala-")))
-       (with-temp-file src-file (insert body))
-       (org-babel-eval
-        (concat org-babel-scala-command " " src-file) "")))
-    (`value
-     (let* ((src-file (org-babel-temp-file "scala-"))
-            (wrapper (format org-babel-scala-wrapper-method body)))
-       (with-temp-file src-file (insert wrapper))
-       (let ((raw (org-babel-eval
-                   (concat org-babel-scala-command " " src-file) "")))
-         (org-babel-result-cond result-params
-           raw
-           (org-babel-script-escape raw)))))))
-
-
-(defun org-babel-prep-session:scala (_session _params)
-  "Prepare SESSION according to the header arguments specified in PARAMS."
-  (error "Sessions are not (yet) supported for Scala"))
-
-(defun org-babel-scala-initiate-session (&optional _session)
-  "If there is not a current inferior-process-buffer in SESSION
-then create.  Return the initialized session.  Sessions are not
-supported in Scala."
-  nil)
-
-(provide 'ob-scala)
-
-
-
-;;; ob-scala.el ends here
diff --git a/lisp/org/ob-vala.el b/lisp/org/ob-vala.el
new file mode 100644
index 00000000000..3998e2d4e28
--- /dev/null
+++ b/lisp/org/ob-vala.el
@@ -0,0 +1,115 @@
+;;; ob-vala.el --- Babel functions for Vala evaluation -*- lexical-binding: t; -*-
+
+;; Copyright (C) 2017 Free Software Foundation, Inc.
+
+;; Author: Christian Garbs <mitch@cgarbs.de>
+;; Keywords: literate programming, reproducible research
+;; Homepage: http://orgmode.org
+
+;;; License:
+
+;; GNU Emacs is free software: you can redistribute it and/or modify
+;; it under the terms of the GNU General Public License as published by
+;; the Free Software Foundation, either version 3 of the License, or
+;; (at your option) any later version.
+
+;; GNU Emacs is distributed in the hope that it will be useful,
+;; but WITHOUT ANY WARRANTY; without even the implied warranty of
+;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+;; GNU General Public License for more details.
+
+;; You should have received a copy of the GNU General Public License
+;; along with GNU Emacs.  If not, see <https://www.gnu.org/licenses/>.
+
+;;; Commentary:
+
+;; ob-vala.el provides Babel support for the Vala language
+;; (see http://live.gnome.org/Vala for details)
+
+;;; Requirements:
+
+;; - Vala compiler binary (valac)
+;; - Vala development environment (Vala libraries etc.)
+;;
+;; vala-mode.el is nice to have for code formatting, but is not needed
+;; for ob-vala.el
+
+;;; Code:
+
+(require 'ob)
+
+(declare-function org-trim "org" (s &optional keep-lead))
+
+;; File extension.
+(add-to-list 'org-babel-tangle-lang-exts '("vala" . "vala"))
+
+;; Header arguments empty by default.
+(defvar org-babel-default-header-args:vala '())
+
+(defcustom org-babel-vala-compiler "valac"
+  "Command used to compile a C source code file into an executable.
+May be either a command in the path, like \"valac\"
+or an absolute path name, like \"/usr/local/bin/valac\".
+Parameters may be used like this: \"valac -v\""
+  :group 'org-babel
+  :version "26.1"
+  :package-version '(Org . "9.1")
+  :type 'string)
+
+;; This is the main function which is called to evaluate a code
+;; block.
+;;
+;; - run Vala compiler and create a binary in a temporary file
+;;   - compiler/linker flags can be set via :flags header argument
+;; - if compilation succeeded, run the binary
+;;   - commandline parameters to the binary can be set via :cmdline
+;;     header argument
+;;   - stdout will be parsed as RESULT (control via :result-params
+;;     header argument)
+;;
+;; There is no session support because Vala is a compiled language.
+;;
+;; This function is heavily based on ob-C.el
+(defun org-babel-execute:vala (body params)
+  "Execute a block of Vala code with Babel.
+This function is called by `org-babel-execute-src-block'."
+  (message "executing Vala source code block")
+  (let* ((tmp-src-file (org-babel-temp-file
+                        "vala-src-"
+                        ".vala"))
+         (tmp-bin-file (org-babel-temp-file "vala-bin-" org-babel-exeext))
+         (cmdline (cdr (assq :cmdline params)))
+         (flags (cdr (assq :flags params))))
+    (with-temp-file tmp-src-file (insert body))
+    (org-babel-eval
+     (format "%s %s -o %s %s"
+             org-babel-vala-compiler
+             (mapconcat #'identity
+                        (if (listp flags) flags (list flags)) " ")
+             (org-babel-process-file-name tmp-bin-file)
+             (org-babel-process-file-name tmp-src-file)) "")
+    (when (file-executable-p tmp-bin-file)
+        (let ((results
+               (org-trim
+                (org-babel-eval
+                 (concat tmp-bin-file (if cmdline (concat " " cmdline) "")) ""))))
+          (org-babel-reassemble-table
+           (org-babel-result-cond (cdr (assq :result-params params))
+             (org-babel-read results)
+             (let ((tmp-file (org-babel-temp-file "vala-")))
+               (with-temp-file tmp-file (insert results))
+               (org-babel-import-elisp-from-file tmp-file)))
+           (org-babel-pick-name
+            (cdr (assq :colname-names params)) (cdr (assq :colnames params)))
+           (org-babel-pick-name
+            (cdr (assq :rowname-names params)) (cdr (assq :rownames params))))))))
+
+(defun org-babel-prep-session:vala (_session _params)
+  "Prepare a session.
+This function does nothing as Vala is a compiled language with no
+support for sessions."
+  (error "Vala is a compiled language -- no support for sessions"))
+
+(provide 'ob-vala)
+
+;;; ob-vala.el ends here
diff --git a/lisp/org/org-duration.el b/lisp/org/org-duration.el
new file mode 100644
index 00000000000..3e5f0f56a5b
--- /dev/null
+++ b/lisp/org/org-duration.el
@@ -0,0 +1,446 @@
+;;; org-duration.el --- Library handling durations   -*- lexical-binding: t; -*-
+
+;; Copyright (C) 2017  Free Software Foundation, Inc.
+
+;; Author: Nicolas Goaziou <mail@nicolasgoaziou.fr>
+;; Keywords: outlines, hypermedia, calendar, wp
+
+;; This program is free software; you can redistribute it and/or modify
+;; it under the terms of the GNU General Public License as published by
+;; the Free Software Foundation, either version 3 of the License, or
+;; (at your option) any later version.
+
+;; This program is distributed in the hope that it will be useful,
+;; but WITHOUT ANY WARRANTY; without even the implied warranty of
+;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+;; GNU General Public License for more details.
+
+;; You should have received a copy of the GNU General Public License
+;; along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+;;; Commentary:
+
+;; This library provides tools to manipulate durations.  A duration
+;; can have multiple formats:
+;;
+;;   - 3:12
+;;   - 1:23:45
+;;   - 1y 3d 3h 4min
+;;   - 3d 13:35
+;;   - 2.35h
+;;
+;; More accurately, it consists of numbers and units, as defined in
+;; variable `org-duration-units', separated with white spaces, and
+;; a "H:MM" or "H:MM:SS" part.  White spaces are tolerated between the
+;; number and its relative unit.  Variable `org-duration-format'
+;; controls durations default representation.
+;;
+;; The library provides functions allowing to convert a duration to,
+;; and from, a number of minutes: `org-duration-to-minutes' and
+;; `org-duration-from-minutes'.  It also provides two lesser tools:
+;; `org-duration-p', and `org-duration-h:mm-only-p'.
+;;
+;; Users can set the number of minutes per unit, or define new units,
+;; in `org-duration-units'.  The library also supports canonical
+;; duration, i.e., a duration that doesn't depend on user's settings,
+;; through optional arguments.
+
+;;; Code:
+
+(require 'cl-lib)
+(require 'org-macs)
+(declare-function org-trim "org-trim" (s &optional keep-lead))
+
+
+;;; Public variables
+
+(defconst org-duration-canonical-units
+  `(("min" . 1)
+    ("h" . 60)
+    ("d" . ,(* 60 24)))
+  "Canonical time duration units.
+See `org-duration-units' for details.")
+
+(defcustom org-duration-units
+  `(("min" . 1)
+    ("h" . 60)
+    ("d" . ,(* 60 24))
+    ("w" . ,(* 60 24 7))
+    ("m" . ,(* 60 24 30))
+    ("y" . ,(* 60 24 365.25)))
+  "Conversion factor to minutes for a duration.
+
+Each entry has the form (UNIT . MODIFIER).
+
+In a duration string, a number followed by UNIT is multiplied by
+the specified number of MODIFIER to obtain a duration in minutes.
+
+For example, the following value
+
+  \\=`((\"min\" . 1)
+    (\"h\" . 60)
+    (\"d\" . ,(* 60 8))
+    (\"w\" . ,(* 60 8 5))
+    (\"m\" . ,(* 60 8 5 4))
+    (\"y\" . ,(* 60 8 5 4 10)))
+
+is meaningful if you work an average of 8 hours per day, 5 days
+a week, 4 weeks a month and 10 months a year.
+
+When setting this variable outside the Customize interface, make
+sure to call the following command:
+
+  \\[org-duration-set-regexps]"
+  :group 'org-agenda
+  :version "26.1"
+  :package-version '(Org . "9.1")
+  :set (lambda (var val) (set-default var val) (org-duration-set-regexps))
+  :initialize 'custom-initialize-changed
+  :type '(choice
+          (const :tag "H:MM" 'h:mm)
+          (const :tag "H:MM:SS" 'h:mm:ss)
+          (alist :key-type (string :tag "Unit")
+                 :value-type (number :tag "Modifier"))))
+
+(defcustom org-duration-format '(("d" . nil) (special . h:mm))
+  "Format definition for a duration.
+
+The value can be set to, respectively, the symbols `h:mm:ss' or
+`h:mm', which means a duration is expressed as, respectively,
+a \"H:MM:SS\" or \"H:MM\" string.
+
+Alternatively, the value can be a list of entries following the
+pattern:
+
+  (UNIT . REQUIRED?)
+
+UNIT is a unit string, as defined in `org-duration-units'.  The
+time duration is formatted using only the time components that
+are specified here.
+
+Units with a zero value are skipped, unless REQUIRED? is non-nil.
+In that case, the unit is always used.
+
+Eventually, the list can contain one of the following special
+entries:
+
+  (special . h:mm)
+  (special . h:mm:ss)
+
+    Units shorter than an hour are ignored.  The hours and
+    minutes part of the duration is expressed unconditionally
+    with H:MM, or H:MM:SS, pattern.
+
+  (special . PRECISION)
+
+    A duration is expressed with a single unit, PRECISION being
+    the number of decimal places to show.  The unit chosen is the
+    first one required or with a non-zero integer part.  If there
+    is no such unit, the smallest one is used.
+
+For example,
+
+   ((\"d\" . nil) (\"h\" . t) (\"min\" . t))
+
+means a duration longer than a day is expressed in days, hours
+and minutes, whereas a duration shorter than a day is always
+expressed in hours and minutes, even when shorter than an hour.
+
+On the other hand, the value
+
+  ((\"d\" . nil) (\"min\" . nil))
+
+means a duration longer than a day is expressed in days and
+minutes, whereas a duration shorter than a day is expressed
+entirely in minutes, even when longer than an hour.
+
+The following format
+
+  ((\"d\" . nil) (special . h:mm))
+
+means that any duration longer than a day is expressed with both
+a \"d\" unit and a \"H:MM\" part, whereas a duration shorter than
+a day is expressed only as a \"H:MM\" string.
+
+Eventually,
+
+  ((\"d\" . nil) (\"h\" . nil) (special . 2))
+
+expresses a duration longer than a day as a decimal number, with
+a 2-digits fractional part, of \"d\" unit.  A duration shorter
+than a day uses \"h\" unit instead."
+  :group 'org-time
+  :group 'org-clock
+  :version "26.1"
+  :package-version '(Org . "9.1")
+  :type '(choice
+          (const :tag "Use H:MM" h:mm)
+          (const :tag "Use H:MM:SS" h:mm:ss)
+          (repeat :tag "Use units"
+                  (choice
+                   (cons :tag "Use units"
+                         (string :tag "Unit")
+                         (choice (const :tag "Skip when zero" nil)
+                                 (const :tag "Always used" t)))
+                   (cons :tag "Use a single decimal unit"
+                         (const special)
+                         (integer :tag "Number of decimals"))
+                   (cons :tag "Use both units and H:MM"
+                         (const special)
+                         (const h:mm))
+                   (cons :tag "Use both units and H:MM:SS"
+                         (const special)
+                         (const h:mm:ss))))))
+
+
+;;; Internal variables and functions
+
+(defconst org-duration--h:mm-re
+  "\\`[ \t]*[0-9]+\\(?::[0-9]\\{2\\}\\)\\{1,2\\}[ \t]*\\'"
+  "Regexp matching a duration expressed with H:MM or H:MM:SS format.
+See `org-duration--h:mm:ss-re' to only match the latter.  Hours
+can use any number of digits.")
+
+(defconst org-duration--h:mm:ss-re
+  "\\`[ \t]*[0-9]+\\(?::[0-9]\\{2\\}\\)\\{2\\}[ \t]*\\'"
+  "Regexp matching a duration expressed H:MM:SS format.
+See `org-duration--h:mm-re' to also support H:MM format.  Hours
+can use any number of digits.")
+
+(defvar org-duration--unit-re nil
+  "Regexp matching a duration with an unit.
+Allowed units are defined in `org-duration-units'.  Match group
+1 contains the bare number.  Match group 2 contains the unit.")
+
+(defvar org-duration--full-re nil
+  "Regexp matching a duration expressed with units.
+Allowed units are defined in `org-duration-units'.")
+
+(defvar org-duration--mixed-re nil
+  "Regexp matching a duration expressed with units and H:MM or H:MM:SS format.
+Allowed units are defined in `org-duration-units'.  Match group
+1 contains units part.  Match group 2 contains H:MM or H:MM:SS
+part.")
+
+(defun org-duration--modifier (unit &optional canonical)
+  "Return modifier associated to string UNIT.
+When optional argument CANONICAL is non-nil, refer to
+`org-duration-canonical-units' instead of `org-duration-units'."
+  (or (cdr (assoc unit (if canonical
+                           org-duration-canonical-units
+                         org-duration-units)))
+      (error "Unknown unit: %S" unit)))
+
+
+;;; Public functions
+
+;;;###autoload
+(defun org-duration-set-regexps ()
+  "Set duration related regexps."
+  (interactive)
+  (setq org-duration--unit-re
+        (concat "\\([0-9]+\\(?:\\.[0-9]*\\)?\\)[ \t]*"
+                ;; Since user-defined units in `org-duration-units'
+                ;; can differ from canonical units in
+                ;; `org-duration-canonical-units', include both in
+                ;; regexp.
+                (regexp-opt (mapcar #'car (append org-duration-canonical-units
+                                                  org-duration-units))
+                            t)))
+  (setq org-duration--full-re
+        (format "\\`[ \t]*%s\\(?:[ \t]+%s\\)*[ \t]*\\'"
+                org-duration--unit-re
+                org-duration--unit-re))
+  (setq org-duration--mixed-re
+        (format "\\`[ \t]*\\(?1:%s\\(?:[ \t]+%s\\)*\\)[ \t]+\
+\\(?2:[0-9]+\\(?::[0-9][0-9]\\)\\{1,2\\}\\)[ \t]*\\'"
+                org-duration--unit-re
+                org-duration--unit-re)))
+
+;;;###autoload
+(defun org-duration-p (s)
+  "Non-nil when string S is a time duration."
+  (and (stringp s)
+       (or (string-match-p org-duration--full-re s)
+           (string-match-p org-duration--mixed-re s)
+           (string-match-p org-duration--h:mm-re s))))
+
+;;;###autoload
+(defun org-duration-to-minutes (duration &optional canonical)
+  "Return number of minutes of DURATION string.
+
+When optional argument CANONICAL is non-nil, ignore
+`org-duration-units' and use standard time units value.
+
+A bare number is translated into minutes.  The empty string is
+translated into 0.0.
+
+Return value as a float.  Raise an error if duration format is
+not recognized."
+  (cond
+   ((equal duration "") 0.0)
+   ((numberp duration) (float duration))
+   ((string-match-p org-duration--h:mm-re duration)
+    (pcase-let ((`(,hours ,minutes ,seconds)
+                 (mapcar #'string-to-number (split-string duration ":"))))
+      (+ (/ (or seconds 0) 60.0) minutes (* 60 hours))))
+   ((string-match-p org-duration--full-re duration)
+    (let ((minutes 0)
+          (s 0))
+      (while (string-match org-duration--unit-re duration s)
+        (setq s (match-end 0))
+        (let ((value (string-to-number (match-string 1 duration)))
+              (unit (match-string 2 duration)))
+          (cl-incf minutes (* value (org-duration--modifier unit canonical)))))
+      (float minutes)))
+   ((string-match org-duration--mixed-re duration)
+    (let ((units-part (match-string 1 duration))
+          (hms-part (match-string 2 duration)))
+      (+ (org-duration-to-minutes units-part)
+         (org-duration-to-minutes hms-part))))
+   ((string-match-p "\\`[0-9]+\\(\\.[0-9]*\\)?\\'" duration)
+    (float (string-to-number duration)))
+   (t (error "Invalid duration format: %S" duration))))
+
+;;;###autoload
+(defun org-duration-from-minutes (minutes &optional fmt canonical)
+  "Return duration string for a given number of MINUTES.
+
+Format duration according to `org-duration-format' or FMT, when
+non-nil.
+
+When optional argument CANONICAL is non-nil, ignore
+`org-duration-units' and use standard time units value.
+
+Raise an error if expected format is unknown."
+  (pcase (or fmt org-duration-format)
+    (`h:mm
+     (let ((minutes (floor minutes)))
+       (format "%d:%02d" (/ minutes 60) (mod minutes 60))))
+    (`h:mm:ss
+     (let* ((whole-minutes (floor minutes))
+            (seconds (floor (* 60 (- minutes whole-minutes)))))
+       (format "%s:%02d"
+               (org-duration-from-minutes whole-minutes 'h:mm)
+               seconds)))
+    ((pred atom) (error "Invalid duration format specification: %S" fmt))
+    ;; Mixed format.  Call recursively the function on both parts.
+    ((and duration-format
+          (let `(special . ,(and mode (or `h:mm:ss `h:mm)))
+            (assq 'special duration-format)))
+     (let* ((truncated-format
+             ;; Remove "special" mode from duration format in order to
+             ;; recurse properly.  Also remove units smaller or equal
+             ;; to an hour since H:MM part takes care of it.
+             (cl-remove-if-not
+              (lambda (pair)
+                (pcase pair
+                  (`(,(and unit (pred stringp)) . ,_)
+                   (> (org-duration--modifier unit canonical) 60))
+                  (_ nil)))
+              duration-format))
+            (min-modifier               ;smallest modifier above hour
+             (and truncated-format
+                  (apply #'min
+                         (mapcar (lambda (p)
+                                   (org-duration--modifier (car p) canonical))
+                                 truncated-format)))))
+       (if (or (null min-modifier) (< minutes min-modifier))
+           ;; There is not unit above the hour or the smallest unit
+           ;; above the hour is too large for the number of minutes we
+           ;; need to represent.  Use H:MM or H:MM:SS syntax.
+           (org-duration-from-minutes minutes mode canonical)
+         ;; Represent minutes above hour using provided units and H:MM
+         ;; or H:MM:SS below.
+         (let* ((units-part (* min-modifier (/ (floor minutes) min-modifier)))
+                (minutes-part (- minutes units-part)))
+           (concat
+            (org-duration-from-minutes units-part truncated-format canonical)
+            " "
+            (org-duration-from-minutes minutes-part mode))))))
+    ;; Units format.
+    (duration-format
+     (let* ((fractional
+             (let ((digits (cdr (assq 'special duration-format))))
+               (and digits
+                    (or (wholenump digits)
+                        (error "Unknown formatting directive: %S" digits))
+                    (format "%%.%df" digits))))
+            (selected-units
+             (sort (cl-remove-if
+                    ;; Ignore special format cells.
+                    (lambda (pair) (pcase pair (`(special . ,_) t) (_ nil)))
+                    duration-format)
+                   (lambda (a b)
+                     (> (org-duration--modifier (car a) canonical)
+                        (org-duration--modifier (car b) canonical))))))
+       (cond
+        ;; Fractional duration: use first unit that is either required
+        ;; or smaller than MINUTES.
+        (fractional
+         (let* ((unit (car
+                       (or (cl-find-if
+                            (lambda (pair)
+                              (pcase pair
+                                (`(,u . ,req?)
+                                 (or req?
+                                     (<= (org-duration--modifier u canonical)
+                                         minutes)))))
+                            selected-units)
+                           ;; Fall back to smallest unit.
+                           (org-last selected-units))))
+                (modifier (org-duration--modifier unit canonical)))
+           (concat (format fractional (/ (float minutes) modifier)) unit)))
+        ;; Otherwise build duration string according to available
+        ;; units.
+        ((org-string-nw-p
+          (org-trim
+           (mapconcat
+            (lambda (units)
+              (pcase-let* ((`(,unit . ,required?) units)
+                           (modifier (org-duration--modifier unit canonical)))
+                (cond ((<= modifier minutes)
+                       (let ((value (if (integerp modifier)
+                                        (/ (floor minutes) modifier)
+                                      (floor (/ minutes modifier)))))
+                         (cl-decf minutes (* value modifier))
+                         (format " %d%s" value unit)))
+                      (required? (concat " 0" unit))
+                      (t ""))))
+            selected-units
+            ""))))
+        ;; No unit can properly represent MINUTES.  Use the smallest
+        ;; one anyway.
+        (t
+         (pcase-let ((`((,unit . ,_)) (last selected-units)))
+           (concat "0" unit))))))))
+
+;;;###autoload
+(defun org-duration-h:mm-only-p (times)
+  "Non-nil when every duration in TIMES has \"H:MM\" or \"H:MM:SS\" format.
+
+TIMES is a list of duration strings.
+
+Return nil if any duration is expressed with units, as defined in
+`org-duration-units'.  Otherwise, if any duration is expressed
+with \"H:MM:SS\" format, return `h:mm:ss'.  Otherwise, return
+`h:mm'."
+  (let (hms-flag)
+    (catch :exit
+      (dolist (time times)
+        (cond ((string-match-p org-duration--full-re time)
+               (throw :exit nil))
+              ((string-match-p org-duration--mixed-re time)
+               (throw :exit nil))
+              (hms-flag nil)
+              ((string-match-p org-duration--h:mm:ss-re time)
+               (setq hms-flag 'h:mm:ss))))
+      (or hms-flag 'h:mm))))
+
+
+;;; Initialization
+
+(org-duration-set-regexps)
+
+(provide 'org-duration)
+;;; org-duration.el ends here