raco pkg remove: check for all named packages before removing any

Closes #3846

pkgs/racket-test/tests/pkg/tests-remove.rkt

@@ -34,6 +34,10 @@
    (shelly-install "remove test with immediately redundant package name"
                    "test-pkgs/pkg-test1.zip"
                    "pkg-test1 pkg-test1")
+   (shelly-install "remove test where second in given list does not exist"
+                   "test-pkgs/pkg-test1.zip"
+                   $ "raco pkg remove pkg-test1 not-there" =exit> 1 =stderr> #rx"not currently installed"
+                   $ "racket -e '(require pkg-test1)'" =exit> 0)
    (shelly-install "remove of dep fails"
                    "test-pkgs/pkg-test1.zip"
                    $ "raco pkg show -l -u -a" =stdout> #rx"Package +Checksum +Source\npkg-test1 +[a-f0-9.]+ +\\(file .+/test-pkgs/pkg-test1.zip\"\\)\n"

racket/collects/pkg/private/pkg-db.rkt

@@ -25,7 +25,8 @@
          update-auto
          scope->links-file
          installed-pkg-table
-         installed-pkg-names)
+         installed-pkg-names
+         pkg-not-installed)
 
 (define (read-pkg-db)
   (unless (pkg-lock-held)

racket/collects/pkg/private/remove.rkt

@@ -85,6 +85,13 @@
     (list->set all-pkgs))
   (define metadata-ns (make-metadata-namespace))
   (define in-pkgs (remove-duplicates given-pkgs))
+
+  ;; Check that all packages are installed, so we don't remove half of
+  ;; them and leave things in an potentialy inconsistent state:
+  (for ([pkg (in-list in-pkgs)])
+    (unless (set-member? all-pkgs pkg)
+      (pkg-not-installed pkg db)))
+
   (define remove-pkgs
     (if auto?
         ;; compute fixpoint: