patch 9.0.1617: charidx() result is not consistent with byteidx()
Problem: charidx() and utf16idx() result is not consistent with byteidx().
Solution: When the index is equal to the length of the text return the
lenght of the text instead of -1. (Yegappan Lakshmanan,
closes #12503)
diff --git a/runtime/doc/builtin.txt b/runtime/doc/builtin.txt
index 0cbfe21..5fd401c 100644
--- a/runtime/doc/builtin.txt
+++ b/runtime/doc/builtin.txt
@@ -1528,11 +1528,13 @@
When {utf16} is present and TRUE, {idx} is used as the UTF-16
index in the String {expr} instead of as the byte index.
- Returns -1 if the arguments are invalid or if {idx} is greater
- than the index of the last byte in {string}. An error is
- given if the first argument is not a string, the second
- argument is not a number or when the third argument is present
- and is not zero or one.
+ Returns -1 if the arguments are invalid or if there are less
+ than {idx} bytes. If there are exactly {idx} bytes the length
+ of the string in characters is returned.
+
+ An error is given and -1 is returned if the first argument is
+ not a string, the second argument is not a number or when the
+ third argument is present and is not zero or one.
See |byteidx()| and |byteidxcomp()| for getting the byte index
from the character index and |utf16idx()| for getting the
@@ -10119,8 +10121,8 @@
<
*utf16idx()*
utf16idx({string}, {idx} [, {countcc} [, {charidx}]])
- Same as |charidx()| but returns the UTF-16 index of the byte
- at {idx} in {string} (after converting it to UTF-16).
+ Same as |charidx()| but returns the UTF-16 code unit index of
+ the byte at {idx} in {string} (after converting it to UTF-16).
When {charidx} is present and TRUE, {idx} is used as the
character index in the String {string} instead of as the byte
@@ -10128,6 +10130,10 @@
An {idx} in the middle of a UTF-8 sequence is rounded upwards
to the end of that sequence.
+ Returns -1 if the arguments are invalid or if there are less
+ than {idx} bytes in {string}. If there are exactly {idx} bytes
+ the length of the string in UTF-16 code units is returned.
+
See |byteidx()| and |byteidxcomp()| for getting the byte index
from the UTF-16 index and |charidx()| for getting the
character index from the UTF-16 index.