[elpa] master b180abf 087/399: counsel.el (counsel-compile): clean-up get-make-targets

[Oleh Krehel]

branch: master
commit b180abf2cb8149047245df8b35ac8ae2f9c5b9f0
Author: Alex Bennée <address@hidden>
Commit: Oleh Krehel <address@hidden>

    counsel.el (counsel-compile): clean-up get-make-targets
    
    The original code called a pipeline of shell functions to get the list
    of PHONY targets. One of the consequence of this is we picked up a
    bunch of noise if the make crapped out with an error. To avoid this we
    bring all the text extraction into emacs with a temp buffer and only
    process it if make is happy.
    
    This is also a first step towards what we would need if we wanted to
    use counsel--async-command to gather stuff and update the targets
    dynamically.
    
    ---
    v2
      - use bare form of (rx) for phony macro
      - tweak wording in comments
      - push/nconc/sort the results
      - revert de-hyphenating
      - let*->let
    
    Fixes #1972
---
 counsel.el | 46 +++++++++++++++++++++++++++++++---------------
 1 file changed, 31 insertions(+), 15 deletions(-)

diff --git a/counsel.el b/counsel.el
index 27eeb1e..bbe6884 100644
--- a/counsel.el
+++ b/counsel.el
@@ -5196,32 +5196,48 @@ N in your system."
   "List of potential build subdirectory names to check for."
   :type '(repeat directory))
 
+(defvar counsel-compile-phony-pattern
+  (rx bol ".PHONY:" space (group (+ print)) eol)
+  "Regexp for extracting phony targets from Makefiles.")
+
 ;; This is loosely based on the Bash Make completion code
+(defun counsel-compile--probe-make-targets (dir)
+  "Return a list of Make targets for DIR.
+
+Return an empty list is Make exits with an error.  This might
+happen because some sort of configuration needs to be done first
+or the source tree is pristine and being used for multiple build
+trees."
+  (let ((default-directory dir)
+        (targets))
+    (with-temp-buffer
+      ;; 0 = no-rebuild, -q & 1 needs rebuild, 2 error (for GNUMake at
+      ;; least)
+      (when (> 2 (call-process "make" nil t nil "-nqp"))
+        (goto-char (point-min))
+        (while (re-search-forward counsel-compile-phony-pattern nil t)
+          (push (split-string (match-string-no-properties 1))
+                targets))))
+    (sort (apply #'nconc targets) 'string-lessp)))
+
 (defun counsel--compile-get-make-targets (srcdir &optional blddir)
   "Return a list of Make targets for a given SRCDIR/BLDDIR combination.
 
 We search the Makefile for a list of phony targets which are
-generally the top-level targets a Make system provides.
+generally the top level targets a Make system provides.
 The resulting strings are tagged with properties that
 `counsel-compile-history' can use for filtering results."
-  (let* ((default-directory (or blddir srcdir))
-         (fmt (format (propertize "make %s %%s" 'cmd t)
-                      counsel-compile-make-args))
-         (suffix (and blddir
-                      (concat (propertize " in " 'face 'font-lock-warning-face)
-                              (propertize blddir 'face 'dired-directory))))
-         (props `(srcdir ,srcdir blddir ,default-directory)))
+  (let ((fmt (format (propertize "make %s %%s" 'cmd t)
+                     counsel-compile-make-args))
+        (suffix (and blddir
+                     (concat (propertize " in " 'face 'font-lock-warning-face)
+                             (propertize blddir 'face 'dired-directory))))
+        (props `(srcdir ,srcdir blddir ,default-directory)))
     (mapcar (lambda (target)
               (setq target (concat (format fmt target) suffix))
               (add-text-properties 0 (length target) props target)
               target)
-            (split-string (shell-command-to-string "\
-make -nqp |\
- grep -B 1 PHONY |\
- grep ':' |\
- cut -d ':' -f 1 |\
- sort")
-                          "\n"))))
+            (counsel-compile--probe-make-targets (or blddir srcdir)))))
 
 (defun counsel-compile-get-make-invocation (&optional blddir)
   "Have a look in the root directory for any build control files.