[nongnu] elpa/racket-mode 3536288c55 1/2: racket-expand-file: Improve behavior when no steps

[ELPA Syncer]

branch: elpa/racket-mode
commit 3536288c55f1b61182fe58740ec685990c471a52
Author: Greg Hendershott <git@greghendershott.com>
Commit: Greg Hendershott <git@greghendershott.com>

    racket-expand-file: Improve behavior when no steps
    
    When no steps at all, still show "Final" output.
    
    When no steps left, show simple message there is nothing left to
    expand (as opposed to having the back end raise an exception).
    
    Although I noticed this when investigating #697, it is adjacent not
    strictly related.
---
 racket-stepper.el         | 30 ++++++++++++++++--------------
 racket/commands/macro.rkt | 10 +++++-----
 test/racket-tests.el      |  2 +-
 3 files changed, 22 insertions(+), 20 deletions(-)

diff --git a/racket-stepper.el b/racket-stepper.el
index b9ce42af16..25dd4d7c82 100644
--- a/racket-stepper.el
+++ b/racket-stepper.el
@@ -160,20 +160,22 @@ INTO-BASE is treated as a raw command prefix arg and 
converted to boolp."
                                        ,(and into-base t))
                        #'racket-stepper--insert)))
 
-(defun racket-stepper--insert (steps)
-  (with-current-buffer (racket--stepper-buffer-name)
-    (let ((inhibit-read-only t))
-      (goto-char (point-max))
-      (dolist (step steps)
-        (pcase step
-          (`(original . ,text)
-           (delete-region (point-min) (point-max))
-           (insert "Original\n" text "\n" "\n"))
-          (`(final    . ,text) (insert "Final\n" text "\n"))
-          (`(,label   . ,diff) (insert label "\n" diff "\n"))))
-      (racket-stepper-previous-item)
-      (when (equal (selected-window) (get-buffer-window (current-buffer)))
-        (recenter)))))
+(defun racket-stepper--insert (nothing-or-steps)
+  (if (eq nothing-or-steps 'nothing)
+      (message "Nothing to expand")
+    (with-current-buffer (racket--stepper-buffer-name)
+      (let ((inhibit-read-only t))
+        (goto-char (point-max))
+        (dolist (step nothing-or-steps)
+          (pcase step
+            (`(original . ,text)
+             (delete-region (point-min) (point-max))
+             (insert "Original\n" text "\n" "\n"))
+            (`(final  . ,text) (insert "Final\n" text "\n"))
+            (`(,label . ,diff) (insert label "\n" diff "\n"))))
+        (racket-stepper-previous-item)
+        (when (equal (selected-window) (get-buffer-window (current-buffer)))
+          (recenter))))))
 
 (defun racket-stepper-step (prefix)
   (interactive "P")
diff --git a/racket/commands/macro.rkt b/racket/commands/macro.rkt
index 613c474ac5..8de37d196b 100644
--- a/racket/commands/macro.rkt
+++ b/racket/commands/macro.rkt
@@ -22,8 +22,10 @@
          macro-stepper/next)
 
 (define step/c (cons/c (or/c 'original string? 'final) string?))
-(define step-proc/c (-> (or/c 'next 'all) (listof step/c)))
+(define step-proc/c (-> (or/c 'next 'all)
+                        (or/c 'nothing (listof step/c))))
 (define step-proc #f)
+(define (nothing-step-proc _) 'nothing)
 
 (define/contract (make-expr-stepper str)
   (-> string? step-proc/c)
@@ -73,7 +75,7 @@
                      (stepper-text stx
                                    (if into-base? (λ _ #t) (not-in-base)))))
   (define step-num #f)
-  (define step-last-after "")
+  (define step-last-after (pretty-format-syntax stx))
   (log-racket-mode-debug "~v ~v ~v" path into-base? raw-step)
   (define/contract (step what) step-proc/c
     (cond [(not step-num)
@@ -131,11 +133,9 @@
   (macro-stepper/next 'next))
 
 (define/contract (macro-stepper/next what) step-proc/c
-  (unless step-proc
-    (error 'macro-stepper "Nothing to expand"))
   (define v (step-proc what))
   (match v
-    [(list (cons 'final _)) (set! step-proc #f)]
+    [(list (cons 'final _)) (set! step-proc nothing-step-proc)]
     [_ (void)])
   v)
 
diff --git a/test/racket-tests.el b/test/racket-tests.el
index 08fd33f11e..f302bc16e9 100644
--- a/test/racket-tests.el
+++ b/test/racket-tests.el
@@ -417,7 +417,7 @@ want to use the value of `racket-program' at run time."
 (module foo racket/base (#%module-begin (define x 42) x))
 
 «f:Final»
-
+(module foo racket/base (#%module-begin (define x 42) x))
 ")
 
 (ert-deftest racket-tests/expand-file-shallow ()