[PATCH] common: Avoid unnecessary ambiguity in argparse.

[Daniel Kahn Gillmor]

* common/argparse.c (find_long_option): Avoid unnecessary ambiguity.

If two struct ARGPARSE_OPTS share a prefix in their long_opt name, but
have the exact same short_opt and flags, they are aliases and not
distinct options.  Avoid reporting this as an ambiguity, so that (for
example) both --clearsign and --clear-sign can be invoked as --clear.

Signed-off-by: Daniel Kahn Gillmor <dkg at fifthhorseman.net>
Debian-Bug-Id: 850475
---
 common/argparse.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/common/argparse.c b/common/argparse.c
index dce725af9..d395229ad 100644
--- a/common/argparse.c
+++ b/common/argparse.c
@@ -898,7 +898,9 @@ find_long_option( ARGPARSE_ARGS *arg,
 	    int j;
 	    for(j=i+1; opts[j].short_opt; j++ ) {
 		if( opts[j].long_opt
-		    && !strncmp( opts[j].long_opt, keyword, n ) )
+		    && !strncmp( opts[j].long_opt, keyword, n )
+                    && !(opts[j].short_opt == opts[i].short_opt
+                         && opts[j].flags == opts[i].flags ) )
 		    return -2;	/* abbreviation is ambiguous */
 	    }
 	    return i;
-- 
2.11.0