Raise TypeError for endless non-numeric range include?

Beginless ranges previously raised TypeError for this case,
except for string ranges, which had unexpected behavior:

  ('a'..'z').include?('ww') # false
  (..'z').include?('ww') # previously true, now TypeError

Use of include? with endless ranges could previously result
in an infinite loop.

This splits off a range_string_cover_internal function from
range_include_internal.

Fixes [Bug #18580]

1 files changed, 37 insertions, 12 deletions

diff --git a/range.c b/range.c
index 0c3dc51c73..94b6e5a560 100644
--- a/range.c
+++ b/range.c
@@ -1679,7 +1679,9 @@ range_inspect(VALUE range)
     return rb_exec_recursive(inspect_range, range, 0);
 }
 
-static VALUE range_include_internal(VALUE range, VALUE val, int string_use_cover);
+static VALUE range_include_internal(VALUE range, VALUE val);
+static VALUE range_string_cover_internal(VALUE range, VALUE val);
+VALUE rb_str_include_range_p(VALUE beg, VALUE end, VALUE val, VALUE exclusive);
 
 /*
  *  call-seq:
@@ -1723,7 +1725,7 @@ static VALUE range_include_internal(VALUE range, VALUE val, int string_use_cover
 static VALUE
 range_eqq(VALUE range, VALUE val)
 {
-    VALUE ret = range_include_internal(range, val, 1);
+    VALUE ret = range_string_cover_internal(range, val);
     if (!UNDEF_P(ret)) return ret;
     return r_cover_p(range, RANGE_BEG(range), RANGE_END(range), val);
 }
@@ -1763,13 +1765,13 @@ range_eqq(VALUE range, VALUE val)
 static VALUE
 range_include(VALUE range, VALUE val)
 {
-    VALUE ret = range_include_internal(range, val, 0);
+    VALUE ret = range_include_internal(range, val);
     if (!UNDEF_P(ret)) return ret;
     return rb_call_super(1, &val);
 }
 
 static VALUE
-range_include_internal(VALUE range, VALUE val, int string_use_cover)
+range_string_cover_internal(VALUE range, VALUE val)
 {
     VALUE beg = RANGE_BEG(range);
     VALUE end = RANGE_END(range);
@@ -1783,15 +1785,9 @@ range_include_internal(VALUE range, VALUE val, int string_use_cover)
     }
     else if (RB_TYPE_P(beg, T_STRING) || RB_TYPE_P(end, T_STRING)) {
         if (RB_TYPE_P(beg, T_STRING) && RB_TYPE_P(end, T_STRING)) {
-            if (string_use_cover) {
-                return r_cover_p(range, beg, end, val);
-            }
-            else {
-                VALUE rb_str_include_range_p(VALUE beg, VALUE end, VALUE val, VALUE exclusive);
-                return rb_str_include_range_p(beg, end, val, RANGE_EXCL(range));
-            }
+            return r_cover_p(range, beg, end, val);
         }
-        else if (NIL_P(beg)) {
+        if (NIL_P(beg)) {
             VALUE r = rb_funcall(val, id_cmp, 1, end);
             if (NIL_P(r)) return Qfalse;
             if (RANGE_EXCL(range)) {
@@ -1805,6 +1801,35 @@ range_include_internal(VALUE range, VALUE val, int string_use_cover)
             return RBOOL(rb_cmpint(r, beg, val) <= 0);
         }
     }
+
+    if (NIL_P(beg) || NIL_P(end)) {
+        rb_raise(rb_eTypeError, "cannot determine inclusion in beginless/endless ranges");
+    }
+
+    return Qundef;
+}
+
+static VALUE
+range_include_internal(VALUE range, VALUE val)
+{
+    VALUE beg = RANGE_BEG(range);
+    VALUE end = RANGE_END(range);
+    int nv = FIXNUM_P(beg) || FIXNUM_P(end) ||
+             linear_object_p(beg) || linear_object_p(end);
+
+    if (nv ||
+        !NIL_P(rb_check_to_integer(beg, "to_int")) ||
+        !NIL_P(rb_check_to_integer(end, "to_int"))) {
+        return r_cover_p(range, beg, end, val);
+    }
+    else if (RB_TYPE_P(beg, T_STRING) && RB_TYPE_P(end, T_STRING)) {
+        return rb_str_include_range_p(beg, end, val, RANGE_EXCL(range));
+    }
+
+    if (NIL_P(beg) || NIL_P(end)) {
+        rb_raise(rb_eTypeError, "cannot determine inclusion in beginless/endless ranges");
+    }
+
     return Qundef;
 }