patch 8.2.2233: cannot convert a byte index into a character index
Problem: Cannot convert a byte index into a character index.
Solution: Add charidx(). (Yegappan Lakshmanan, closes #7561)
diff --git a/src/testdir/test_functions.vim b/src/testdir/test_functions.vim
index dd4429e..89db161 100644
--- a/src/testdir/test_functions.vim
+++ b/src/testdir/test_functions.vim
@@ -1132,6 +1132,31 @@
call assert_fails("call byteidxcomp([], 0)", 'E730:')
endfunc
+" Test for charidx()
+func Test_charidx()
+ let a = 'xáb́y'
+ call assert_equal(0, charidx(a, 0))
+ call assert_equal(1, charidx(a, 3))
+ call assert_equal(2, charidx(a, 4))
+ call assert_equal(3, charidx(a, 7))
+ call assert_equal(-1, charidx(a, 8))
+ call assert_equal(-1, charidx('', 0))
+
+ " count composing characters
+ call assert_equal(0, charidx(a, 0, 1))
+ call assert_equal(2, charidx(a, 2, 1))
+ call assert_equal(3, charidx(a, 4, 1))
+ call assert_equal(5, charidx(a, 7, 1))
+ call assert_equal(-1, charidx(a, 8, 1))
+ call assert_equal(-1, charidx('', 0, 1))
+
+ call assert_fails('let x = charidx([], 1)', 'E474:')
+ call assert_fails('let x = charidx("abc", [])', 'E474:')
+ call assert_fails('let x = charidx("abc", 1, [])', 'E474:')
+ call assert_fails('let x = charidx("abc", 1, -1)', 'E1023:')
+ call assert_fails('let x = charidx("abc", 1, 2)', 'E1023:')
+endfunc
+
func Test_count()
let l = ['a', 'a', 'A', 'b']
call assert_equal(2, count(l, 'a'))