diff --git a/src/core/peg.c b/src/core/peg.c
index b3445521..93d43d0e 100644
--- a/src/core/peg.c
+++ b/src/core/peg.c
@@ -286,7 +286,7 @@ tail:
             const uint8_t *next_text;
             CapState cs = cap_save(s);
             down1(s);
-            while (text < s->text_end) {
+            while (text <= s->text_end) {
                 CapState cs2 = cap_save(s);
                 next_text = peg_rule(s, rule_a, text);
                 if (next_text) {
@@ -296,7 +296,7 @@ tail:
                 text++;
             }
             up1(s);
-            if (text >= s->text_end) {
+            if (text > s->text_end) {
                 cap_load(s, cs);
                 return NULL;
             }
diff --git a/test/suite0003.janet b/test/suite0003.janet
index 2f6c2995..02e15913 100644
--- a/test/suite0003.janet
+++ b/test/suite0003.janet
@@ -473,4 +473,12 @@
 
 (check-deep '(* (int 2) -1) "123" nil)
 
+# to/thru bug
+(check-deep '(to -1) "aaaa" @[])
+(check-deep '(thru -1) "aaaa" @[])
+(check-deep ''(to -1) "aaaa" @["aaaa"])
+(check-deep ''(thru -1) "aaaa" @["aaaa"])
+(check-deep '(to "b") "aaaa" nil)
+(check-deep '(thru "b") "aaaa" nil)
+
 (end-suite)