Emacs: fix logging when merlin call is interrupted

Currently, "interrupted" is only logged when the result parsing is
interrupted (by C-g), but it seems pretty clear that the original
intent (and more useful behavior) was to log "interrupted" when the
actual merlin call was interrupted.

We do this by setting up separate condition handlers for (1) the
result parse failing; and (2) the merlin call or result parse being
interrupted.

CHANGES.md

@@ -2,6 +2,10 @@ unreleased
 ==========
   + merlin binary
     - Handle concurrent server start (#1622)
+  + editor modes
+    - emacs: call merlin-client-logger with "interrupted" if the
+      merlin binary itself is interrupted, not just the parsing of the
+      result (#1626).
 
 
 merlin 4.9

emacs/merlin.el

@@ -565,16 +565,19 @@ argument (lookup appropriate binary, setup logging, pass global settings)"
 
 (defun merlin-call (command &rest args)
   "Execute a command and parse output: return an sexp on success or throw an error"
-  (let* ((binary (merlin-command))
-         (result (merlin--call-merlin command args)))
+  (let ((binary (merlin-command)) result)
     (condition-case err
-        (setq result (car (read-from-string result)))
-      (error
-        (merlin-client-logger binary command -1 "failure")
-        (error "merlin: error %s trying to parse answer: %s"
-               err result))
+        (progn
+          (setq result (merlin--call-merlin command args))
+          (condition-case err
+              (setq result (car (read-from-string result)))
+            (error
+             (merlin-client-logger binary command -1 "failure")
+             (error "merlin: error %s trying to parse answer: %s"
+                    err result))))
       (quit
-        (merlin-client-logger binary command -1 "interrupted")))
+       (merlin-client-logger binary command -1 "interrupted")
+       (signal (car err) (cdr err))))
     (let* ((notifications (cdr-safe (assoc 'notifications result)))
            (timing (cdr-safe (assoc 'timing result)))
            (class (cdr-safe (assoc 'class result)))