Allow with-*-group/user to be a no-op if first parameter is f

basis/unix/groups/groups-docs.factor

@@ -65,8 +65,8 @@ HELP: user-groups
 
 HELP: with-effective-group
 { $values
-     { "string/id" "a string or a group id" } { "quot" quotation } }
+     { "string/id/f" "a string, a group id, or f" } { "quot" quotation } }
-{ $description "Sets the effective group name and calls the quotation. Restors the effective group name on success or on error after the call." } ;
+{ $description "Sets the effective group name and calls the quotation. Restors the effective group name on success or on error after the call. If the first parameter is " { $link f } ", the quotation is called as the current user." } ;
 
 HELP: with-group-cache
 { $values
@@ -75,8 +75,8 @@ HELP: with-group-cache
 
 HELP: with-real-group
 { $values
-     { "string/id" "a string or a group id" } { "quot" quotation } }
+     { "string/id/f" "a string or a group id" } { "quot" quotation } }
-{ $description "Sets the real group name and calls the quotation. Restores the current group name on success or on error after the call." } ;
+{ $description "Sets the real group name and calls the quotation. Restores the current group name on success or on error after the call. If the first parameter is " { $link f } ", the quotation is called as the current user." } ;
 
 ARTICLE: "unix.groups" "Unix groups"
 "The " { $vocab-link "unix.groups" } " vocabulary contains words that return information about Unix groups."

basis/unix/groups/groups-tests.factor

@@ -28,3 +28,6 @@ IN: unix.groups.tests
 [ f ]
 [ "please-oh-please-don't-have-a-group-named-this123lalala" group-struct ] unit-test
 [ "please-oh-please-don't-have-a-group-named-this123lalala" ?group-id ] must-fail
+
+[ 3 ] [ f [ 3 ] with-effective-group ] unit-test
+[ 3 ] [ f [ 3 ] with-real-group ] unit-test

basis/unix/groups/groups.factor

@@ -109,14 +109,20 @@ GENERIC: set-real-group ( obj -- )
 
 GENERIC: set-effective-group ( obj -- )
 
-: with-real-group ( string/id quot -- )
+: (with-real-group) ( string/id quot -- )
     '[ _ set-real-group @ ]
     real-group-id '[ _ set-real-group ] [ ] cleanup ; inline
 
-: with-effective-group ( string/id quot -- )
+: with-real-group ( string/id/f quot -- )
+    over [ (with-real-group) ] [ nip call ] if ; inline
+
+: (with-effective-group) ( string/id quot -- )
     '[ _ set-effective-group @ ]
     effective-group-id '[ _ set-effective-group ] [ ] cleanup ; inline
 
+: with-effective-group ( string/id/f quot -- )
+    over [ (with-effective-group) ] [ nip call ] if ; inline
+
 <PRIVATE
 
 : (set-real-group) ( id -- )

basis/unix/users/users-docs.factor

@@ -67,8 +67,8 @@ HELP: user-id
 
 HELP: with-effective-user
 { $values
-     { "string/id" "a string or a uid" } { "quot" quotation } }
+     { "string/id/f" "a string, a uid, or f" } { "quot" quotation } }
-{ $description "Sets the effective user-name and calls the quotation. Restores the current user-name on success or on error after the call." } ;
+{ $description "Sets the effective user-name and calls the quotation. Restores the current user-name on success or on error after the call. If the first parameter is " { $link f } ", the quotation is called as the current user." } ;
 
 HELP: with-user-cache
 { $values
@@ -77,8 +77,8 @@ HELP: with-user-cache
 
 HELP: with-real-user
 { $values
-     { "string/id" "a string or a uid" } { "quot" quotation } }
+     { "string/id/f" "a string, a uid, or f" } { "quot" quotation } }
-{ $description "Sets the real user-name and calls the quotation. Restores the current user-name on success or on error after the call." } ;
+{ $description "Sets the real user-name and calls the quotation. Restores the current user-name on success or on error after the call. If the first parameter is " { $link f } ", the quotation is called as the current user." } ;
 
 {
     real-user-name real-user-id set-real-user

basis/unix/users/users-tests.factor

@@ -28,3 +28,6 @@ IN: unix.users.tests
 
 [ f ] [ "thisusershouldnotexistabcdefg12345asdfasdfasdfasdfasdfasdfasdf" user-id ] unit-test
 [ "thisusershouldnotexistabcdefg12345asdfasdfasdfasdfasdfasdfasdf" ?user-id ] must-fail
+
+[ 3 ] [ f [ 3 ] with-effective-user ] unit-test
+[ 3 ] [ f [ 3 ] with-real-user ] unit-test

basis/unix/users/users.factor

@@ -85,16 +85,22 @@ GENERIC: set-real-user ( string/id -- )
 
 GENERIC: set-effective-user ( string/id -- )
 
-: with-real-user ( string/id quot -- )
+: (with-real-user) ( string/id quot -- )
     '[ _ set-real-user @ ]
     real-user-id '[ _ set-real-user ]
     [ ] cleanup ; inline
 
-: with-effective-user ( string/id quot -- )
+: with-real-user ( string/id/f quot -- )
+    over [ (with-real-user) ] [ nip call ] if ; inline
+
+: (with-effective-user) ( string/id quot -- )
     '[ _ set-effective-user @ ]
     effective-user-id '[ _ set-effective-user ]
     [ ] cleanup ; inline
 
+: with-effective-user ( string/id/f quot -- )
+    over [ (with-effective-user) ] [ nip call ] if ; inline
+
 <PRIVATE
 
 : (set-real-user) ( id -- )