Implement `String#count`; ref
mruby restriction:
In mruby, `String#count` does not take multiple pattern arguments,
but only one pattern.
MODIFY
mrbgems/mruby-string-ext/src/string.c
mrbgems/mruby-string-ext/src/string.c
@@ -632,6 +632,39 @@ mrb_str_squeeze_bang(mrb_state *mrb, mrb_value str)
return mrb_nil_value();
}
+/*
+ * call_seq:
+ * str.count([other_str]) -> integer
+ *
+ * Each other_str parameter defines a set of characters to count. The
+ * intersection of these sets defines the characters to count in str. Any
+ * other_str that starts with a caret ^ is negated. The sequence c1-c2
+ * means all characters between c1 and c2. The backslash character \ can
+ * be used to escape ^ or - and is otherwise ignored unless it appears at
+ * the end of a sequence or the end of a other_str.
+ */
+static mrb_value
+mrb_str_count(mrb_state *mrb, mrb_value str)
+{
+ mrb_value v_pat = mrb_nil_value();
+ struct tr_pattern *pat = NULL;
+ mrb_int i;
+ char *s;
+ mrb_int len;
+ mrb_int count = 0;
+
+ mrb_get_args(mrb, "S", &v_pat);
+ pat = tr_parse_pattern(mrb, pat, v_pat, TRUE);
+ s = RSTRING_PTR(str);
+ len = RSTRING_LEN(str);
+ for (i = 0; i < len; i++) {
+ mrb_int n = tr_find_character(pat, s[i]);
+
+ if (n >= 0) count++;
+ }
+ return mrb_fixnum_value(count);
+}
+
static mrb_value
mrb_str_hex(mrb_state *mrb, mrb_value self)
{
@@ -1017,6 +1050,7 @@ mrb_mruby_string_ext_gem_init(mrb_state* mrb)
mrb_define_method(mrb, s, "swapcase", mrb_str_swapcase, MRB_ARGS_NONE());
mrb_define_method(mrb, s, "concat", mrb_str_concat_m, MRB_ARGS_REQ(1));
mrb_define_method(mrb, s, "<<", mrb_str_concat_m, MRB_ARGS_REQ(1));
+ mrb_define_method(mrb, s, "count", mrb_str_count, MRB_ARGS_REQ(1));
mrb_define_method(mrb, s, "tr", mrb_str_tr, MRB_ARGS_REQ(2));
mrb_define_method(mrb, s, "tr!", mrb_str_tr_bang, MRB_ARGS_REQ(2));
mrb_define_method(mrb, s, "tr_s", mrb_str_tr_s, MRB_ARGS_REQ(2));

MODIFY
mrbgems/mruby-string-ext/test/string.rb
mrbgems/mruby-string-ext/test/string.rb
@@ -147,6 +147,15 @@ assert('String#casecmp') do
assert_equal 0, "abcdef".casecmp(o)
end
+assert('String#count') do
+ s = "abccdeff123"
+ assert_equal 1, s.count("a")
+ assert_equal 2, s.count("ab")
+ assert_equal 9, s.count("^c")
+ assert_equal 8, s.count("a-z")
+ assert_equal 4, s.count("a0-9")
+end
+
assert('String#tr') do
assert_equal "ABC", "abc".tr('a-z', 'A-Z')
assert_equal "hippo", "hello".tr('el', 'ip')

Implement `String#count`; ref #4086

mruby restriction:
In mruby, `String#count` does not take multiple pattern arguments,
but only one pattern.