diff options
| author | zverok <[email protected]> | 2024-08-25 20:58:47 +0300 |
|---|---|---|
| committer | Akinori Musha <[email protected]> | 2024-09-03 16:21:42 +0900 |
| commit | 245ed2fc890f7f33526e1c0f42b79c30366493e6 (patch) | |
| tree | 8879a308984a12dcb53580543fa1a20c638f026f /range.c | |
| parent | 452eb24b1566f3fd8319e9eeb0ece6758eace08d (diff) | |
Range#step: restore legacy behavior for String ranges
Notes
Notes:
Merged: https://github.com/ruby/ruby/pull/11454
Diffstat (limited to 'range.c')
| -rw-r--r-- | range.c | 60 |
1 files changed, 56 insertions, 4 deletions
@@ -309,6 +309,34 @@ range_each_func(VALUE range, int (*func)(VALUE, VALUE), VALUE arg) } } +// NB: Two functions below (step_i_iter and step_i) are used only to maintain the +// backward-compatible behavior for string ranges with integer steps. If that branch +// will be removed from range_step, these two can go, too. +static bool +step_i_iter(VALUE arg) +{ + VALUE *iter = (VALUE *)arg; + + if (FIXNUM_P(iter[0])) { + iter[0] -= INT2FIX(1) & ~FIXNUM_FLAG; + } + else { + iter[0] = rb_funcall(iter[0], '-', 1, INT2FIX(1)); + } + if (iter[0] != INT2FIX(0)) return false; + iter[0] = iter[1]; + return true; +} + +static int +step_i(VALUE i, VALUE arg) +{ + if (step_i_iter(arg)) { + rb_yield(i); + } + return 0; +} + static int discrete_object_p(VALUE obj) { @@ -430,9 +458,18 @@ range_step_size(VALUE range, VALUE args, VALUE eobj) * * For non-Numeric ranges, step absence is an error: * - * ('a'..'z').step { p _1 } + * (Time.utc(2022, 3, 1)..Time.utc(2022, 2, 24)).step { p _1 } * # raises: step is required for non-numeric ranges (ArgumentError) * + * For backward compatibility reasons, String ranges support the iteration both with + * string step and with integer step. In the latter case, the iteration is performed + * by calculating the next values with String#succ: + * + * ('a'..'e').step(2) { p _1 } + * # Prints: a, c, e + * ('a'..'e').step { p _1 } + * # Default step 1; prints: a, b, c, d, e + * */ static VALUE range_step(int argc, VALUE *argv, VALUE range) @@ -445,11 +482,15 @@ range_step(int argc, VALUE *argv, VALUE range) const VALUE b_num_p = rb_obj_is_kind_of(b, rb_cNumeric); const VALUE e_num_p = rb_obj_is_kind_of(e, rb_cNumeric); + // For backward compatibility reasons (conforming to behavior before 3.4), String supports + // both old behavior ('a'..).step(1) and new behavior ('a'..).step('a') + // Hence the additional conversion/addional checks. + const VALUE sb = rb_check_string_type(b); if (rb_check_arity(argc, 0, 1)) step = argv[0]; else { - if (b_num_p || (NIL_P(b) && e_num_p)) + if (b_num_p || !NIL_P(sb) || (NIL_P(b) && e_num_p)) step = INT2FIX(1); else rb_raise(rb_eArgError, "step is required for non-numeric ranges"); @@ -520,8 +561,19 @@ range_step(int argc, VALUE *argv, VALUE range) } else if (b_num_p && step_num_p && ruby_float_step(b, e, step, EXCL(range), TRUE)) { /* done */ - } - else { + } else if (!NIL_P(sb) && FIXNUM_P(step)) { + // backwards compatibility behavior for String only, when no step/Integer step is passed + // See discussion in https://bugs.ruby-lang.org/issues/18368 + + VALUE iter[2] = {INT2FIX(1), step}; + + if (NIL_P(e)) { + rb_str_upto_endless_each(sb, step_i, (VALUE)iter); + } + else { + rb_str_upto_each(sb, e, EXCL(range), step_i, (VALUE)iter); + } + } else { v = b; if (!NIL_P(e)) { if (b_num_p && step_num_p && r_less(step, INT2FIX(0)) < 0) { |