port-info: output fields in the order given on the command line (#103)

* port-info: output fields in the order given on the command line

Currently due to the use of 'array names', the output of
'port info --multiple-fields' are displayed in a random order.
Now, the fields are kept in a list which preserves their order they
were given on the command line.
This has the effect of also allowing duplicate fields to be displayed.

Also, the order of arguments given on the command line are available
for any action (not just info).

Closes: https://trac.macports.org/ticket/57003

src/port/port.tcl

@@ -1912,7 +1912,8 @@ proc action_log { action portlist opts } {
 
 
 proc action_info { action portlist opts } {
-    global global_variations
+    global global_options global_variations
+
     set status 0
     if {[require_portlist portlist]} {
         return 1
@@ -2094,7 +2095,20 @@ proc action_info { action portlist opts } {
 
         # Spin through action options, emitting information for any found
         set fields {}
-        set opts_todo [array names options ports_info_*]
+
+        # This contains the display fields in random order
+        set opts_info [array names options ports_info_*]
+        # This contains all parameters in order given on command line
+        set opts_action $global_options(options_${action}_order)
+        # Get the display fields in order provided on command line
+        #  ::struct::set intersect does not keep order of items
+        set opts_todo {}
+        foreach elem $opts_action {
+            if {$elem in $opts_info} {
+                lappend opts_todo $elem
+            }
+        }
+
         set fields_tried {}
         if {![llength $opts_todo]} {
             set opts_todo {ports_info_heading
@@ -4468,6 +4482,8 @@ proc parse_options { action ui_options_name global_options_name } {
     upvar $ui_options_name ui_options
     upvar $global_options_name global_options
 
+    set options_order(${action}) {}
+
     while {[moreargs]} {
         set arg [lookahead]
 
@@ -4495,6 +4511,7 @@ proc parse_options { action ui_options_name global_options_name } {
                     set kargc [lindex $kopts 0 1]
                     if {$kargc == 0} {
                         set global_options(ports_${action}_${key}) yes
+                        lappend options_order(${action}) ports_${action}_${key}
                     } else {
                         set args {}
                         while {[moreargs] && $kargc > 0} {
@@ -4591,6 +4608,7 @@ proc parse_options { action ui_options_name global_options_name } {
 
         advance
     }
+    set global_options(options_${action}_order) $options_order(${action})
 }
 
 # acquire exclusive registry lock for actions that need it