Increase test coverage and improve completion commenting

src/complete.cpp

@@ -920,6 +920,8 @@ bool completer_t::complete_param(const wcstring &scmd_orig, const wcstring &spop
                 }
             } else if (popt[0] == L'-') {
                 // Set to true if we found a matching old-style switch.
+                // Here we are testing the previous argument,
+                // to see how we should complete the current argument
                 bool old_style_match = false;
 
                 // If we are using old style long options, check for them first.
@@ -943,6 +945,8 @@ bool completer_t::complete_param(const wcstring &scmd_orig, const wcstring &spop
                         const complete_entry_opt_t *o = &*oiter;
                         // Gnu-style options with _optional_ arguments must be specified as a single
                         // token, so that it can be differed from a regular argument.
+                        // Here we are testing the previous argument for a GNU-style match,
+                        // to see how we should complete the current argument
                         if (o->type == option_type_double_long && !(o->result_mode & NO_COMMON))
                             continue;
 
@@ -960,6 +964,7 @@ bool completer_t::complete_param(const wcstring &scmd_orig, const wcstring &spop
             continue;
         }
 
+        // Now we try to complete an option itself
         for (option_list_t::const_iterator oiter = options.begin(); oiter != options.end();
              ++oiter) {
             const complete_entry_opt_t *o = &*oiter;

tests/test6.in

@@ -56,6 +56,16 @@ complete -c TestDoubleDash -l TestDoubleDashOption
 complete -C'TestDoubleDash -' | sort
 echo "Expect no output:" (complete -C'TestDoubleDash -- -' | sort)
 
+# fish seems to have always handled "exclusive" options strangely
+# It seems to treat them the same as "old-style" (single-dash) long options
+echo "Testing exclusive options"
+complete -c TestExclusive -x -s Q
+complete -c TestExclusive -x -s W
+complete -c TestExclusive -s A
+echo "Expect -A -Q -W:" (complete -C'TestExclusive -' | sort | string join ' ')
+echo "Expect -AQ -AW:" (complete -C'TestExclusive -A' | sort | string join ' ')
+echo "Expect no output 1:" (complete -C'TestExclusive -Q')
+echo "Expect no output 2:" (complete -C'TestExclusive -W')
 
 # Test that directory completions work correctly
 if begin; rm -rf test6.tmp.dir; and mkdir test6.tmp.dir; end

tests/test6.out

@@ -33,6 +33,11 @@ CCCC:
 Test that -- suppresses option completions
 --TestDoubleDashOption
 Expect no output:
+Testing exclusive options
+Expect -A -Q -W: -A -Q -W
+Expect -AQ -AW: -AQ -AW
+Expect no output 1:
+Expect no output 2:
 implicit cd complete works
 no implicit cd complete after 'command'
 PATH does not cause incorrect implicit cd