From fef7cffd021f26d6881872c20a18191c3c2968d1 Mon Sep 17 00:00:00 2001
From: Ming Zhao <ming.zhao@databricks.com>
Date: Tue, 26 Oct 2021 04:36:45 +0000
Subject: [PATCH] Introduce `scala-indent:defition-parameter-scaling-factor`
config to control whether the parameter list of function/class should have a
different indentation level.
See discussion in #172
---
scala-mode-indent.el | 11 +++++++++++
scala-mode-syntax.el | 19 +++++++++++++++++++
2 files changed, 30 insertions(+)
diff --git a/scala-mode-indent.el b/scala-mode-indent.el
index 486ae65..69f6fcf 100644
--- a/scala-mode-indent.el
+++ b/scala-mode-indent.el
@@ -16,6 +16,14 @@ indentation will be one or two steps depending on context."
:safe #'integerp
:group 'scala)
+(defcustom scala-indent:defition-parameter-scaling-factor 1
+ "Scale the number of spaces used to indent the parameter list
+of class/function definitions. See also
+https://github.com/hvesalai/emacs-scala-mode/issues/172"
+ :type 'integer
+ :safe #'integerp
+ :group 'scala)
+
(defcustom scala-indent:indent-value-expression nil
"Whether or not to indent multi-line value expressions, with
one extra step. When true, indenting will be
@@ -629,6 +637,9 @@ anchor for calculating block indent for current point (or point
(> (line-number-at-pos) (line-number-at-pos anchor))
(> start (match-beginning 0))))
(+ (* 2 scala-indent:step) lead))
+ ;; optionally double the step for parameter list
+ ((scala-syntax:in-definition-parameter-list anchor start)
+ (+ (* scala-indent:defition-parameter-scaling-factor scala-indent:step) lead))
;; normal block line
(t (+ scala-indent:step lead)))))
diff --git a/scala-mode-syntax.el b/scala-mode-syntax.el
index edab1ab..6801d48 100644
--- a/scala-mode-syntax.el
+++ b/scala-mode-syntax.el
@@ -1018,6 +1018,25 @@ val a, b = (1, 2)
(scala-syntax:find-brace-equals-or-next)
(scala-syntax:handle-brace-equals-or-next))
+(defun scala-syntax:in-definition-parameter-list (anchor start)
+ "Return t if the (anchor, start) region is the parameter list
+of a definition(class, def, etc.)"
+ (save-excursion
+ (goto-char anchor)
+ (when
+ (or (string= "class" (current-word))
+ (string= "def" (current-word)))
+ ;; try to find (
+ (while (and (< (point) start)
+ (/= (char-after) ?\())
+ (forward-char))
+ (when (< (point) start)
+ ;; And we haven't see ) yet.
+ (while (and (< (point) start)
+ (/= (char-after) ?\)))
+ (forward-char))
+ (= (point) start)))))
+
(defun scala-syntax:find-brace-equals-or-next ()
(scala-syntax:go-to-pos
(save-excursion