Fix axzsh_is_widechar_terminal() logic

[ax-zsh.git] / core / 11_terminal / 11_terminal.zshrc

diff --git a/core/11_terminal/11_terminal.zshrc b/core/11_terminal/11_terminal.zshrc
index 3990129368f10b44c800fbb280b9e49f5cfabef8..a15c1d4137ca54a1dcfed630d5a8efa6b5b8a366 100644 (file)
--- a/core/11_terminal/11_terminal.zshrc
+++ b/core/11_terminal/11_terminal.zshrc
@@ -21,7 +21,21 @@ function axzsh_is_utf_terminal {
 }
 alias isutfenv=axzsh_is_utf_terminal
 
-# Check if terminal supports "wide" characters.
+# Get the length of a string when shown on the terminal. The return code of the
+# function is the length in "cells". Note: Echo'ing the length to the terminal,
+# which looks cleaner at first, doesn't work: this command can't be called with
+# its stdin and/or stdout redirected, as it it must be able to interact with the
+# terminal (write to and read from it).
+function axzsh_get_displayed_length {
+       echo -ne "$*\033[6n"
+       read -s -d\[ garbage
+       read -s -d R pos
+       echo -ne "\033[1K\r"
+       return $((${pos#*;} - 1))
+}
+
+# Check if terminal correctly handles "wide" characters, which means, displays
+# them with the correct width (>1).
 # <https://unix.stackexchange.com/questions/184345/detect-how-much-of-unicode-my-terminal-supports-even-through-screen>
 typeset -g _axzsh_is_widechar_terminal_cache
 function axzsh_is_widechar_terminal {
@@ -36,12 +50,8 @@ function _axzsh_is_widechar_terminal {
        [[ -t 1 ]] || return 1
        [[ -z "$AXZSH_PLUGIN_CHECK" ]] || return 1
        axzsh_is_utf_terminal || return 1
-       echo -ne "🍀\033[6n"
-       read -s -d\[ garbage
-       read -s -d R pos
-       echo -ne "\033[1K\r"
-       [[ "${pos#*;}" -eq 2 ]] || return 1
-       return 0
+       axzsh_get_displayed_length "🍀"
+       [[ $? -eq 2 ]] && return 0 || return 1
 }
 
 # Test for "modern" terminal