[nongnu] elpa/rust-mode 2a81393 094/486: added optional method chain indentations for emacs major mode

[ELPA Syncer]

branch: elpa/rust-mode
commit 2a81393b29fc0b133056d8a8c3cd8d0221fa7def
Author: Daniel Raloff <draloff@side2.com>
Commit: Daniel Raloff <draloff@side2.com>

    added optional method chain indentations for emacs major mode
---
 rust-mode.el | 29 ++++++++++++++++++++++++++++-
 1 file changed, 28 insertions(+), 1 deletion(-)

diff --git a/rust-mode.el b/rust-mode.el
index 6917e9e..f66df6c 100644
--- a/rust-mode.el
+++ b/rust-mode.el
@@ -49,6 +49,11 @@
   :type 'integer
   :group 'rust-mode)
 
+(defcustom rust-indent-method-chain nil
+  "Indent Rust method chains, aligned by the '.' operators"
+  :type 'boolean
+  :group 'rust-mode)
+
 (defun rust-paren-level () (nth 0 (syntax-ppss)))
 (defun rust-in-str-or-cmnt () (nth 8 (syntax-ppss)))
 (defun rust-rewind-past-str-cmnt () (goto-char (nth 8 (syntax-ppss))))
@@ -72,6 +77,15 @@
        (backward-word 1))
       (current-column))))
 
+(defun rust-align-to-method-chain ()
+  (save-excursion
+       (previous-line)
+       (end-of-line)
+       (backward-word 1)
+       (backward-char)
+       (when (looking-at "\\..+\(.*\)\n")
+         (- (current-column) rust-indent-offset))))
+
 (defun rust-rewind-to-beginning-of-current-level-expr ()
   (let ((current-level (rust-paren-level)))
     (back-to-indentation)
@@ -94,10 +108,13 @@
                    ;; the inside of it correctly relative to the outside.
                    (if (= 0 level)
                        0
+                                        (or
+                                         (when rust-indent-method-chain
+                                               (rust-align-to-method-chain))
                      (save-excursion
                        (backward-up-list)
                        (rust-rewind-to-beginning-of-current-level-expr)
-                       (+ (current-column) rust-indent-offset)))))
+                       (+ (current-column) rust-indent-offset))))))
              (cond
               ;; A function return type is indented to the corresponding 
function arguments
               ((looking-at "->")
@@ -109,6 +126,16 @@
               ;; A closing brace is 1 level unindended
               ((looking-at "}") (- baseline rust-indent-offset))
 
+                         ;;Line up method chains by their .'s
+                         ((when (and rust-indent-method-chain
+                                                 (looking-at "\..+\(.*\);?\n"))
+                                (or
+                                 (let ((method-indent 
(rust-align-to-method-chain)))
+                                       (when method-indent
+                                         (+ method-indent rust-indent-offset)))
+                                 (+ baseline rust-indent-offset))))
+
+                         
               ;; Doc comments in /** style with leading * indent to line up 
the *s
               ((and (nth 4 (syntax-ppss)) (looking-at "*"))
                (+ 1 baseline))