runtests: skip disabled tests unless -f is used

To make it easier to write ranges like '115 to 229' without that
explicitly enabling tests that are listed in DISABLED, this makes
runtests always skip disabled tests unless the -f command line option is
used.

Previously the code attempted to not run such tests, but didn't do it
correctly.

Closes #7212

tests/runtests.1

@@ -72,6 +72,8 @@ The exclusion types are \fkeyword\fP, \ftest\fP, and \ftool\fP.
 Run the test event-based (if possible). This will make runtests invoke curl
 with --test-event option. This option only works if both curl and libcurl were
 built debug-enabled.
+.IP "-f"
+Force the test to run even if mentioned in DISABLED.
 .IP "-g"
 Run the given test(s) with gdb. This is best used on a single test case and
 curl built --disable-shared. This then fires up gdb with command line set to

tests/runtests.pl

@@ -341,6 +341,7 @@ my $clearlocks;   # force removal of files by killing locking processes
 my $listonly;     # only list the tests
 my $postmortem;   # display detailed info about failed tests
 my $run_event_based; # run curl with --test-event to test the event API
+my $run_disabeled; # run the specific tests even if listed in DISABLED
 
 my %run;          # running server
 my %doesntrun;    # servers that don't work, identified by pidfile
@@ -3559,7 +3560,12 @@ sub singletest {
         logmsg "Warning: test$testnum not present in tests/data/Makefile.inc\n";
     }
     if($disabled{$testnum}) {
-        logmsg "Warning: test$testnum is explicitly disabled\n";
+        if(!$run_disabeled) {
+            $why = "listed in DISABLED";
+        }
+        else {
+            logmsg "Warning: test$testnum is explicitly disabled\n";
+        }
     }
     if($ignored{$testnum}) {
         logmsg "Warning: test$testnum result is ignored\n";
@@ -5401,6 +5407,10 @@ while(@ARGV) {
         # run the tests cases event based if possible
         $run_event_based=1;
     }
+    elsif($ARGV[0] eq "-f") {
+        # force - run the test case even if listed in DISABLED
+        $run_disabeled=1;
+    }
     elsif($ARGV[0] eq "-E") {
         # load additional reasons to skip tests
         shift @ARGV;
@@ -5548,6 +5558,7 @@ Usage: runtests.pl [options] [test selection(s)]
   -d       display server debug info
   -e       event-based execution
   -E file  load the specified file to exclude certain tests
+  -f       forcibly run even if disabled
   -g       run the test case with gdb
   -gw      run the test case with gdb as a windowed application
   -h       this help text
@@ -5582,16 +5593,7 @@ EOHELP
         $number = $1;
         if($fromnum >= 0) {
             for my $n ($fromnum .. $number) {
-                if($disabled{$n}) {
-                    # skip disabled test cases
-                    my $why = "configured as DISABLED";
-                    $skipped++;
-                    $skipped{$why}++;
-                    $teststat[$n]=$why; # store reason for this test case
-                }
-                else {
-                    push @testthis, $n;
-                }
+                push @testthis, $n;
             }
             $fromnum = -1;
         }