Add support for multiple provides of the same identifier in TR.

Closes PR 12807.

original commit: 735b84b08310c44933cd5235719cb7f4a647a1c6

collects/tests/typed-racket/succeed/pr12807.rkt

@@ -0,0 +1,13 @@
+#lang racket/load
+(module a typed/racket
+  (define (foo x) (list x))
+  (provide
+    (rename-out (foo foo2))
+    foo))
+
+(module b racket
+  (require 'a)
+  (foo 2)
+  (foo2 3))
+
+(require 'b)

collects/typed-racket/typecheck/provide-handling.rkt

@@ -31,7 +31,7 @@
   (cond [(s:member i vd (lambda (i j) (free-identifier=? i (binding-name j)))) => car]
         [else #f]))
 
-;; generate-contract-defs : dict[id -> def-binding] dict[id -> id] id -> syntax
+;; generate-contract-defs : dict[id -> def-binding] dict[id -> list[id]] id -> syntax
 ;; defs: defines in this module
 ;; provs: provides in this module
 ;; pos-blame-id: a #%variable-reference for the module
@@ -118,7 +118,10 @@
              new-id))])]
       ;; otherwise, not defined in this module, not our problem
       [else (values #'(begin) internal-id)]))
-  ;; do-one : id id -> syntax
-  (for/list ([(internal-id external-id) (in-dict provs)])
+  ;; Build the final provide with auxilliary definitions
+  (for/list ([(internal-id external-ids) (in-dict provs)])
     (define-values (defs id) (mk internal-id))
-    #`(begin #,defs (provide (rename-out [#,id #,external-id])))))
+    (define provide-forms
+      (for/list ([external-id (in-list external-ids)])
+        #`(rename-out [#,id #,external-id])))
+    #`(begin #,defs (provide #,@provide-forms))))

collects/typed-racket/typecheck/tc-toplevel.rkt

@@ -305,11 +305,11 @@
                [i:id
                 (when (def-stx-binding? (dict-ref def-tbl #'i #f))
                   (set! syntax-provide? #t))
-                (dict-set h #'i #'i)]
+                (dict-update h #'i (lambda (tail) (cons #'i tail)) '())]
                [((~datum rename) in out)
                 (when (def-stx-binding? (dict-ref def-tbl #'in #f))
                   (set! syntax-provide? #t))
-                (dict-set h #'in #'out)]
+                (dict-update h #'in (lambda (tail) (cons #'out tail)) '())]
                [(name:unknown-provide-form . _)
                 (tc-error "provide: ~a not supported by Typed Racket" (syntax-e #'name.name))]
                [_ (int-err "unknown provide form")])))]