Consolidate 'widen' calls

* lisp/progmodes/prog-mode.el (prog-indentation-context):
Un-document all elements but the first.
(prog-widen): Remove.
(http://lists.gnu.org/archive/html/emacs-devel/2017-12/msg00321.html)

* doc/lispref/text.texi (Mode-Specific Indent): Update.

* lisp/progmodes/ruby-mode.el (ruby-calculate-indent):
Don't call widen.

* lisp/progmodes/python.el
(python-indent-guess-indent-offset)
(python-info-current-defun): Replace prog-widen with widen;
these functions are not called during indentation.
(python-indent-context)
(python-indent--calculate-indentation)
(python-info-dedenter-opening-block-message)
(python-info-line-ends-backslash-p)
(python-info-beginning-of-backslash)
(python-info-continuation-line-p)
(python-info-current-defun): Remove 'widen' calls.

* lisp/indent.el (indent-according-to-mode)
(indent-for-tab-command, indent-region): Move them here.

* lisp/textmodes/mhtml-mode.el (mhtml-indent-line):
Bind prog-indentation-context to one-element list.

1 files changed, 9 insertions, 3 deletions

diff --git a/lisp/indent.el b/lisp/indent.el
index d5ba0bd8491..ccf0e99c08b 100644
--- a/lisp/indent.el
+++ b/lisp/indent.el
@@ -69,6 +69,8 @@ variable is `indent-relative' or `indent-relative-maybe', handle
 it specially (since those functions are used for tabbing); in
 that case, indent by aligning to the previous non-blank line."
   (interactive)
+  (save-restriction
+    (widen)
   (syntax-propertize (line-end-position))
   (if (memq indent-line-function
 	    '(indent-relative indent-relative-maybe))
@@ -84,7 +86,7 @@ that case, indent by aligning to the previous non-blank line."
 	    (indent-line-to column)
 	  (save-excursion (indent-line-to column))))
     ;; The normal case.
-    (funcall indent-line-function)))
+    (funcall indent-line-function))))
 
 (defun indent--default-inside-comment ()
   (unless (or (> (current-column) (current-indentation))
@@ -144,7 +146,9 @@ prefix argument is ignored."
           (indent--default-inside-comment)
           (when (or (<= (current-column) (current-indentation))
                     (not (eq tab-always-indent 'complete)))
-            (funcall (default-value 'indent-line-function))))
+            (save-restriction
+              (widen)
+              (funcall (default-value 'indent-line-function)))))
 
       (cond
        ;; If the text was already indented right, try completion.
@@ -538,7 +542,9 @@ column to indent to; if it is nil, use one of the three methods above."
 	  (forward-line 1)))))
    ;; Use indent-region-function is available.
    (indent-region-function
-    (funcall indent-region-function start end))
+    (save-restriction
+      (widen)
+      (funcall indent-region-function start end)))
    ;; Else, use a default implementation that calls indent-line-function on
    ;; each line.
    (t (indent-region-line-by-line start end)))