Add `String#tr_s` and `String#tr_s!`; ref
MODIFY
mrbgems/mruby-string-ext/src/string.c
mrbgems/mruby-string-ext/src/string.c
@@ -380,7 +380,7 @@ tr_get_character(const struct tr_pattern *pat, mrb_int n_th)
}
static mrb_bool
-str_tr(mrb_state *mrb, mrb_value str, mrb_value p1, mrb_value p2)
+str_tr(mrb_state *mrb, mrb_value str, mrb_value p1, mrb_value p2, mrb_bool squeeze)
{
struct tr_pattern *pat;
struct tr_pattern *rep;
@@ -388,6 +388,7 @@ str_tr(mrb_state *mrb, mrb_value str, mrb_value p1, mrb_value p2)
mrb_int len;
mrb_int i;
mrb_bool flag_changed = FALSE;
+ mrb_int lastch = -1;
mrb_str_modify(mrb, mrb_str_ptr(str));
pat = tr_parse_pattern(mrb, p1, TRUE);
@@ -401,6 +402,7 @@ str_tr(mrb_state *mrb, mrb_value str, mrb_value p1, mrb_value p2)
if (n >= 0) {
flag_changed = TRUE;
if (rep == NULL) {
+ compact:
memmove(s + i, s + i + 1, len - i);
len--;
i--;
@@ -408,11 +410,12 @@ str_tr(mrb_state *mrb, mrb_value str, mrb_value p1, mrb_value p2)
else {
mrb_int c = tr_get_character(rep, n);
+ if (squeeze && c == lastch) goto compact;
if (c < 0 || c > 0x80) {
mrb_raisef(mrb, E_ARGUMENT_ERROR, "character (%S) out of range",
mrb_fixnum_value((mrb_int)c));
}
- s[i] = c;
+ lastch = s[i] = c;
}
}
}
@@ -471,7 +474,7 @@ mrb_str_tr(mrb_state *mrb, mrb_value str)
mrb_get_args(mrb, "SS", &p1, &p2);
dup = mrb_str_dup(mrb, str);
- str_tr(mrb, dup, p1, p2);
+ str_tr(mrb, dup, p1, p2, FALSE);
return dup;
}
@@ -488,7 +491,49 @@ mrb_str_tr_bang(mrb_state *mrb, mrb_value str)
mrb_value p1, p2;
mrb_get_args(mrb, "SS", &p1, &p2);
- if (str_tr(mrb, str, p1, p2)) {
+ if (str_tr(mrb, str, p1, p2, FALSE)) {
+ return str;
+ }
+ return mrb_nil_value();
+}
+
+/*
+ * call-seq:
+ * str.tr_s(from_str, to_str) -> new_str
+ *
+ * Processes a copy of str as described under String#tr, then removes
+ * duplicate characters in regions that were affected by the translation.
+ *
+ * "hello".tr_s('l', 'r') #=> "hero"
+ * "hello".tr_s('el', '*') #=> "h*o"
+ * "hello".tr_s('el', 'hx') #=> "hhxo"
+ */
+static mrb_value
+mrb_str_tr_s(mrb_state *mrb, mrb_value str)
+{
+ mrb_value dup;
+ mrb_value p1, p2;
+
+ mrb_get_args(mrb, "SS", &p1, &p2);
+ dup = mrb_str_dup(mrb, str);
+ str_tr(mrb, dup, p1, p2, TRUE);
+ return dup;
+}
+
+/*
+ * call-seq:
+ * str.tr_s!(from_str, to_str) -> str or nil
+ *
+ * Performs String#tr_s processing on str in place, returning
+ * str, or nil if no changes were made.
+ */
+static mrb_value
+mrb_str_tr_s_bang(mrb_state *mrb, mrb_value str)
+{
+ mrb_value p1, p2;
+
+ mrb_get_args(mrb, "SS", &p1, &p2);
+ if (str_tr(mrb, str, p1, p2, TRUE)) {
return str;
}
return mrb_nil_value();
@@ -881,6 +926,8 @@ mrb_mruby_string_ext_gem_init(mrb_state* mrb)
mrb_define_method(mrb, s, "<<", mrb_str_concat_m, 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));
+ mrb_define_method(mrb, s, "tr_s!", mrb_str_tr_s_bang, MRB_ARGS_REQ(2));
mrb_define_method(mrb, s, "start_with?", mrb_str_start_with, MRB_ARGS_REST());
mrb_define_method(mrb, s, "end_with?", mrb_str_end_with, MRB_ARGS_REST());
mrb_define_method(mrb, s, "hex", mrb_str_hex, MRB_ARGS_NONE());

MODIFY
mrbgems/mruby-string-ext/test/string.rb
mrbgems/mruby-string-ext/test/string.rb
@@ -160,6 +160,19 @@ assert('String#tr!') do
assert_equal "ab12222hijklmnopqR", s
end
+assert('String#tr_s') do
+ assert_equal "hero", "hello".tr_s('l', 'r')
+ assert_equal "h*o", "hello".tr_s('el', '*')
+ assert_equal "hhxo", "hello".tr_s('el', 'hx')
+end
+
+assert('String#tr_s!') do
+ s = "hello"
+ assert_equal "hero", s.tr_s!('l', 'r')
+ assert_equal "hero", s
+ assert_nil s.tr_s!('l', 'r')
+end
+
assert('String#start_with?') do
assert_true "hello".start_with?("heaven", "hell")
assert_true !"hello".start_with?("heaven", "paradise")

Add `String#tr_s` and `String#tr_s!`; ref #4086