existing lazy stepper tests passing

in tests/stepper/
test-engine.rkt
- add racket/private/promise to test-namespace using namespace-attach-module

automatic-tests.rkt
- add lazy tests

through-tests.rkt
- fix existing lazy tests lazy1, lazy2, lazy3

language-level-model.rkt
- fix lazy ll-model

in stepper/private/model-settings.rkt
- edit settings for lazy racket

collects/stepper/private/model-settings.rkt

@@ -97,14 +97,15 @@
                           #t))
   
   (define fake-lazy-render-settings
-    (make-render-settings (booleans-as-true/false) 
-                          (constructor-style-printing) 
-                          (abbreviate-cons-as-list) 
-                          print-convert
-                          #f
-                          #t
-			  #f
-                          #f))
+    (make-render-settings (booleans-as-true/false)     ; true-false-printed?
+                          (constructor-style-printing) ; constructor-style-printing?
+                          (abbreviate-cons-as-list)    ; abbreviate-cons-as-list?
+                          (make-fake-render-to-sexp #t #t #t) ; render-to-sexp
+                          #f   ; lifting?
+                          #t   ; show-and/or-clauses-consumed?
+                          #f   ; all-bindings-mutable?
+                          #f)) ; show-lambdas-as-lambdas?
+
   
   (define-struct test-struct () (make-inspector))
   

collects/stepper/private/model.rkt

@@ -227,7 +227,8 @@
         
         ; sends a step to the stepper, except if
         ;  - lhs = rhs
-        ;  - lhs = ellipses, rhs = last-rhs
+        ;  - lhs = ellipses, last-rhs-exps = null (ie, this is first step)
+        ;  - lhs = ellipses, rhs = last-rhs-exps
         (define (send-step lhs-exps lhs-finished-exps 
                            rhs-exps rhs-finished-exps
                            step-kind lhs-posn-info rhs-posn-info)
@@ -238,7 +239,8 @@
           (unless (or (and (step=? lhs-exps rhs-exps)
                            (when DEBUG (printf "LHS = RHS, so skipping\n")))
                       (and (step=? lhs-exps (list #'(... ...)))
-                           (step=? rhs-exps last-rhs-exps)
+                           (or (step=? rhs-exps last-rhs-exps)
+                               (null? last-rhs-exps))
                            (when DEBUG 
                              (printf "LHS = ..., RHS = last RHS, so skipping\n"))))
             (receive-result

collects/tests/stepper/automatic-tests.rkt

@@ -3,6 +3,8 @@
 (require "through-tests.ss" 
          "test-engine.ss")
 
+(define lazy-tests '(lazy1 lazy2 lazy3))
+
 (let ((outer-namespace (current-namespace)))
   (parameterize ([display-only-errors #t]
                  ;; display-only-errors is insufficient, because the evals
@@ -12,7 +14,10 @@
     ;; make sure the tests' print-convert sees the teaching languages' properties
     #;(namespace-attach-module outer-namespace 'mzlib/pconvert-prop (current-namespace))
     (namespace-require 'test-engine/racket-tests)
-    (if (run-all-tests-except '(bad-and bad-cons check-error begin-let-bug prims qq-splice time set! local-set! lazy1 lazy2 lazy3
-                                        local-struct/i local-struct/ilam))
+    (if (and (run-all-tests-except 
+              (append '(bad-and bad-cons check-error begin-let-bug prims qq-splice time 
+                                set! local-set! local-struct/i local-struct/ilam)
+                      lazy-tests))
+             (run-tests lazy-tests))
 	(exit 0)
 	(exit 1))))

collects/tests/stepper/language-level-model.rkt

@@ -29,7 +29,7 @@
   (make-ll-model `(lib "htdp-advanced.ss" "lang") fake-advanced-render-settings #t))
 
 (define lazy
-  (make-ll-model `(lib "lazy.ss" "lazy") fake-lazy-render-settings #f))
+  (make-ll-model `(lib "lazy.rkt" "lazy") fake-lazy-render-settings #f))
 
 
 ;; unsure about the render-settings, here: 

collects/tests/stepper/test-engine.rkt

@@ -180,6 +180,9 @@
 (namespace-attach-module (namespace-anchor->empty-namespace n-anchor)
                          'mzlib/pconvert-prop
                          test-namespace)
+(namespace-attach-module (namespace-anchor->empty-namespace n-anchor)
+                         'racket/private/promise
+                         test-namespace)
 (parameterize ([current-namespace test-namespace])
     (namespace-require 'test-engine/racket-tests)
     ;; make the test engine happy by adding a binding for test~object:

collects/tests/stepper/through-tests.rkt

@@ -1449,10 +1449,7 @@
 
   (t 'lazy1 m:lazy
      (! (+ 3 4))
-     :: 3 -> 3
-     :: 3 -> 3
-     :: 3 -> 3
-     :: {(! (+ 3 4))} -> {7})
+     :: {(force (+ 3 4))} -> {(+ 3 4)} -> {7})
 
   (t 'lazy2 m:lazy
      (+ (+ 3 4) 5)