Fix the macro stepper commands

They didn't get updated correctly to work with possible multiple
REPLs.

racket-repl.el

@@ -57,9 +57,9 @@
 ;; variable `racket--repl-session-id'. (Note that
 ;; `racket-repl-buffer-name' only has meaning for `racket-mode'
 ;; buffers, and `racket--repl-session-id' only has meaning for
-;; `racket-repl-mode' bufers. Emacs variables _exist_ for all buffers
-;; using all major modes. All we can do is remember to ignore them in
-;; some modes.)
+;; `racket-repl-mode' buffers. Emacs variables exist for all buffers
+;; using all major modes. All we can do is remember in which buffers
+;; they mean something as opposed to being ignored..)
 
 (defvar racket-repl-buffer-name "*Racket REPL*"
   "The name of the `racket-repl-mode' buffer associated with `racket-mode' buffer.

racket-stepper.el

@@ -1,6 +1,6 @@
 ;;; racket-stepper.el -*- lexical-binding: t; -*-
 
-;; Copyright (c) 2018 by Greg Hendershott.
+;; Copyright (c) 2018-2020 by Greg Hendershott.
 ;; Portions Copyright (C) 1985-1986, 1999-2013 Free Software Foundation, Inc.
 
 ;; Author: Greg Hendershott
@@ -20,6 +20,7 @@
 (require 'rx)
 (require 'racket-cmd)
 (require 'racket-custom)
+(require 'racket-repl)
 (require 'racket-util)
 
 ;; Need to define this before racket-stepper-mode
@@ -127,11 +128,21 @@ Uses Racket's `expand-once` in the namespace from the most recent
                             (buffer-substring-no-properties beg end)
                             prefix))))
 
+(defvar racket--stepper-repl-session-id nil
+  "The REPL session used when stepping.
+May be nil for 'file stepping, but must be valid for 'expr stepping.")
+
 (defun racket-stepper--start (which str into-base)
   "Ensure buffer and issue initial command.
 WHICH should be 'expr or 'file.
 STR should be the expression or pathname.
 INTO-BASE is treated as a raw prefix arg and converted to boolp."
+  (unless (eq major-mode 'racket-mode)
+    (error "Only works from racket-mode buffers"))
+  (setq racket--stepper-repl-session-id (racket--repl-session-id))
+  (unless (or racket--stepper-repl-session-id
+              (eq which 'file))
+    (error "Only works when the racket-mode buffer has a REPL buffer, and, you should racket-run first"))
   ;; Create buffer if necessary
   (unless (get-buffer racket-stepper--buffer-name)
     (with-current-buffer (get-buffer-create racket-stepper--buffer-name)
@@ -144,7 +155,7 @@ INTO-BASE is treated as a raw prefix arg and converted to boolp."
   (let ((inhibit-read-only t))
     (delete-region (point-min) (point-max))
     (insert "Starting macro expansion stepper... please wait...\n"))
-  (racket--cmd/async nil
+  (racket--cmd/async racket--stepper-repl-session-id
                      `(macro-stepper (,which . ,str)
                                      ,(and into-base t))
                      #'racket-stepper--insert))
@@ -165,7 +176,7 @@ INTO-BASE is treated as a raw prefix arg and converted to boolp."
 
 (defun racket-stepper-step ()
   (interactive)
-  (racket--cmd/async nil
+  (racket--cmd/async racket--stepper-repl-session-id
                      `(macro-stepper/next)
                      #'racket-stepper--insert))
 

racket/commands/macro.rkt

@@ -1,12 +1,17 @@
 #lang racket/base
 
-(require racket/contract
+(require (only-in macro-debugger/stepper-text
+                  stepper-text)
+         racket/contract
          racket/file
          racket/format
          racket/match
+         (only-in racket/path
+                  path-only)
          racket/pretty
          racket/system
          "../elisp.rkt"
+         "../repl.rkt"
          "../syntax.rkt"
          "../util.rkt")
 
@@ -18,6 +23,8 @@
 
 (define/contract (make-expr-stepper str)
   (-> string? step-thunk/c)
+  (unless (current-session-id)
+    (error 'make-expr-stepper "Does not work without a running REPL"))
   (define step-num #f)
   (define last-stx (string->namespace-syntax str))
   (define (step)
@@ -40,15 +47,16 @@
 
 (define/contract (make-file-stepper path into-base?)
   (-> (and/c path-string? absolute-path?) boolean? step-thunk/c)
-  ;; If the dynamic-require fails, just let it bubble up.
-  (define stepper-text (dynamic-require 'macro-debugger/stepper-text 'stepper-text))
   (define stx (file->syntax path))
-  (define-values (dir _name _dir) (split-path path))
-  (define raw-step (parameterize ([current-load-relative-directory dir])
+  (define dir (path-only path))
+  (define ns (make-base-namespace))
+  (define raw-step (parameterize ([current-load-relative-directory dir]
+                                  [current-namespace               ns])
                      (stepper-text stx
                                    (if into-base? (λ _ #t) (not-in-base)))))
   (define step-num #f)
   (define step-last-after "")
+  (log-racket-mode-debug "~v ~v ~v" path into-base? raw-step)
   (define/contract (step) step-thunk/c
     (cond [(not step-num)
            (set! step-num 0)
@@ -59,6 +67,7 @@
            (parameterize ([current-output-port out])
              (cond [(raw-step 'next)
                     (set! step-num (add1 step-num))
+                    (log-racket-mode-debug "~v" (get-output-string out))
                     (match-define (list title before after)
                       (step-parts (get-output-string out)))
                     (set! step-last-after after)