fzy

commit 91bffd5a1c6002c66109f16c9b3ebd94cdb38442
parent f635fc53a3900ce75d01ea26e8eb97411718049f
Author: John Hawthorn <john.hawthorn@gmail.com>
Date:   Sun, 14 Sep 2014 20:26:09 -0700

Fix divide by zero on empty choices list

Diffstat:
M
Makefile
 | 
2
+-
M
choices.c
 | 
6
++++--
M
fzytest.c
 | 
21
+++++++++++++++++++++

3 files changed, 26 insertions(+), 3 deletions(-)
diff --git a/Makefile b/Makefile
@@ -10,7 +10,7 @@ INSTALL_DATA=${INSTALL} -m 644
 
 all: fzy fzytest
 
-fzytest: fzytest.o match.o
+fzytest: fzytest.o match.o choices.o
 	$(CC) $(CFLAGS) $(CCFLAGS) -o $@ $^
 
 test: fzytest
diff --git a/choices.c b/choices.c
@@ -80,10 +80,12 @@ double choices_getscore(choices_t *c, size_t n){
 }
 
 void choices_prev(choices_t *c){
-	c->selection = (c->selection + c->available - 1) % c->available;
+	if(c->available)
+		c->selection = (c->selection + c->available - 1) % c->available;
 }
 
 void choices_next(choices_t *c){
-	c->selection = (c->selection + 1) % c->available;
+	if(c->available)
+		c->selection = (c->selection + 1) % c->available;
 }
 
diff --git a/fzytest.c b/fzytest.c
@@ -1,5 +1,7 @@
 #include <stdio.h>
+
 #include "match.h"
+#include "choices.h"
 
 int testsrun = 0, testsfailed = 0, assertionsrun = 0;
 
@@ -109,6 +111,23 @@ int test_positions_exact(){
 	return 0;
 }
 
+int test_empty_choices(){
+	choices_t choices;
+	choices_init(&choices);
+	assert(choices.size == 0);
+	assert(choices.available == 0);
+	assert(choices.selection == 0);
+
+	choices_prev(&choices);
+	assert(choices.selection == 0);
+
+	choices_next(&choices);
+	assert(choices.selection == 0);
+
+	choices_free(&choices);
+	return 0;
+}
+
 void summary(){
 	printf("%i tests, %i assertions, %i failures\n", testsrun, assertionsrun, testsfailed);
 }
@@ -125,6 +144,8 @@ int main(int argc, char *argv[]){
 	runtest(test_positions_4);
 	runtest(test_positions_exact);
 
+	runtest(test_empty_choices);
+
 	summary();
 
 	/* exit 0 if all tests pass */