Use curly underlines for errors in default themes

Given that this curly underline will also be red, it should be widely understood as error. Since fish always renders immediately (and synchronously), typing "echo" will briefly show an intermediate curly line. Maybe fish should redraw after a timer elapses? This is probably unrelated to this patch. As mentioned in cc9849c279 (Curly underlines in set_color and fish_color_*, 2025-04-13), there are still some terminals that interpret "\e[4:3m" as something other than curly underline. Some of them interpret it as background/foreground color, and some terminal multiplexers downgrade it to straight underlines (which often happens due to a false positive). I want to change this in multiplexers where possible (see https://github.com/orgs/tmux/discussions/4477) but for now, disable this feature in multiplexers (there are just a handful). In a few years, those terminals will maybe agree with XTerm. Until then, use XTGETTCAP as a temporary stepping stone. We could also read the terminfo database but that will give only very few true positives, and lots of false negatives. Better implement XTGETTCAP in the relevant terminals. Note that if the universal variables use the "--track" flag (from the grandparent commit), then rm -rf /tmp/newhome foot -e env $HOME=/tmp/newhome fish xterm -e env $HOME=/tmp/newhome fish will "magically work". For foot, $fish_color_error will have --underline=curly. For xterm, it will not, due to the call to "fish_config theme update". But of course since it's a universal variable, running fish in xterm would also downgrade the fish running in other terminals. Add a "fish_config theme save --yes" flag because "status xtgettcap" requires stdin to be a terminal. I'd probably drop this requirement, and make "status xtgettcap" always use fish's stdin and not its own. That'd be cheating because an external command can't do that but I don't think this change would be hurting anyone.
2026-06-04 15:41:12 -03:00 · 2025-04-13 15:55:21 +02:00
parent 3453565a41
commit ba2ad33a81
32 changed files with 81 additions and 39 deletions
--- a/CHANGELOG.rst
+++ b/CHANGELOG.rst
@@ -69,6 +69,9 @@ Improved terminal support
 ^^^^^^^^^^^^^^^^^^^^^^^^^
 - Support for curly underlines in `fish_color_*` variables and :doc:`set_color <cmds/set_color>` (:issue:`10957`).
 - Underlines can now be colored independent of text (:issue:`7619`).
+- Errors are now highlighted with curly underlines in the default themes.
+  For compatibility with terminals that interpret the curly-underline escape sequence in an unexpected way,
+  the default themes enable this only if the terminal advertises support for the ``Su`` capability via XTGETTCAP.
 - New documentation page `Terminal Compatibility <terminal-compatibility.html>`_ (also accessible via ``man fish-terminal-compatibility``) lists required and optional terminal control sequences used by fish.
 - :doc:`status <cmds/status>` learned the ``xtgettcap`` subcommand, to query terminfo capabilities via XTGETTCAP commands.
 - :doc:`status <cmds/status>` learned the ``xtversion`` subcommand, to show the terminal's name and version (as reported by via the XTVERSION command).
--- a/share/functions/__fish_config_interactive.fish
+++ b/share/functions/__fish_config_interactive.fish
@@ -30,7 +30,7 @@ if status is-interactive
    # Commands to run in interactive sessions can go here
 end" >$__fish_config_dir/config.fish

-        echo yes | fish_config theme save "fish default" --track
+        fish_config theme save "fish default" --yes --track
        set -Ue fish_color_keyword fish_color_option
    end
    if test $__fish_initialized -lt 3800 && test "$fish_color_search_match[1]" = bryellow
--- a/share/functions/__fish_in_gnu_screen.fish
+++ b/share/functions/__fish_in_gnu_screen.fish
@@ -0,0 +1,3 @@
+function __fish_in_gnu_screen
+    test -n "$STY" || contains -- $TERM screen screen-256color
+end
--- a/share/functions/__fish_in_terminal_multiplexer.fish
+++ b/share/functions/__fish_in_terminal_multiplexer.fish
@@ -0,0 +1,9 @@
+function __fish_in_terminal_multiplexer
+    set -l terminal_name "(status xtversion | string match -r '^\S*')"
+    string match -q -- tmux $terminal_name ||
+        __fish_in_gnu_screen ||
+        # Emacs does probably not support multiplexing between multiple parent
+        # terminals, but it is affected by the same issues.  Same for Vim's
+        # :terminal TODO detect that before they implement XTGETTCAP.
+        contains -- $TERM dvtm-256color eterm eterm-color
+end
--- a/share/functions/__fish_shared_key_bindings.fish
+++ b/share/functions/__fish_shared_key_bindings.fish
@@ -78,9 +78,7 @@ function __fish_shared_key_bindings -d "Bindings shared between emacs and vi mod
    bind --preset $argv alt-o __fish_preview_current_file
    bind --preset $argv alt-w __fish_whatis_current_token
    bind --preset $argv ctrl-l (
-        if test -z "$STY"
-            and not string match -qr -- '^(screen|screen-256color)$' $TERM
-            and __fish_xtgettcap indn
+        if not __fish_in_gnu_screen && and __fish_xtgettcap indn
            echo scrollback-push
        end
    ) clear-screen
--- a/share/functions/fish_config.fish
+++ b/share/functions/fish_config.fish
@@ -5,7 +5,7 @@ function fish_config --description "Launch fish's web based configuration" \
    --inherit-variable theme_var_filter

    set -l _flag_track
-    argparse h/help track -- $argv
+    argparse h/help track yes -- $argv
    or return

    if set -q _flag_help
@@ -20,6 +20,10 @@ function fish_config --description "Launch fish's web based configuration" \
        echo >&2 fish_config: --track: unknown option
        return 1
    end
+    if set -q _flag_yes[1] && not { contains "$cmd" prompt theme && test "$argv[1]" = save }
+        echo >&2 fish_config: --yes: unknown option
+        return 1
+    end

    set -q cmd[1]
    or set cmd browse
@@ -152,8 +156,8 @@ function fish_config --description "Launch fish's web based configuration" \
                        functions --erase fish_right_prompt
                    end
                case save
-                    read -P"Overwrite prompt? [y/N]" -l yesno
-                    if string match -riq 'y(es)?' -- $yesno
+                    if set -q _flag_yes[1] ||
+                            { read -P"Overwrite prompt? [y/N]" -l yesno; string match -riq 'y(es)?' -- $yesno }
                        echo Overwriting
                        # Skip the cp if unnecessary,
                        # or we'd throw an error on a stock fish.
@@ -282,8 +286,10 @@ function fish_config --description "Launch fish's web based configuration" \
                    set -l have_colors

                    if contains -- $cmd save
-                        read -P"Overwrite your current theme? [y/N] " -l yesno
-                        if not string match -riq 'y(es)?' -- $yesno
+                        if not set -q _flag_yes &&
+                                { read -P"Overwrite your current theme? [y/N] " -l yesno
+                                    not string match -riq 'y(es)?' -- $yesno
+                                }
                            echo Not overwriting >&2
                            return 1
                        end
@@ -362,10 +368,14 @@ function __fish_config_theme_get
    set -l dirs $__fish_config_dir/themes $__fish_data_dir/tools/web_config/themes
    set -l files $dirs/$argv[1].theme
    set -l file
+    set -l is_default_theme false

    for f in $files
        if test -e "$f"
            set file $f
+            if test $f = $__fish_data_dir/tools/web_config/themes/$argv[1].theme
+                set is_default_theme true
+            end
            break
        end
    end
@@ -373,6 +383,7 @@ function __fish_config_theme_get
    if not set -q file[1]
        if status list-files tools/web_config/themes/$argv[1].theme &>/dev/null
            set file tools/web_config/themes/$argv[1].theme
+            set is_default_theme true
        else
            echo "No such theme: $argv[1]" >&2
            echo "Searched directories: $dirs" >&2
@@ -380,11 +391,18 @@ function __fish_config_theme_get
        end
    end

-    if string match -qr '^tools/' -- $file
-        status get-file $file
-    else
-        string join \n <$file
+    set -l content (
+        if string match -qr '^tools/' -- $file
+            status get-file $file
+        else
+            string join \n <$file
+        end
+    )
+    if $is_default_theme && not __fish_in_gnu_screen && not __fish_xtgettcap Su && not __fish_in_terminal_multiplexer
+        set content (string replace -- --underline=curly "" $content)
    end
+
+    string join \n $content
 end

 function __fish_config_show_tracked_color_vars
--- a/share/tools/web_config/themes/Base16
+++ b/share/tools/web_config/themes/Base16
@@ -10,7 +10,7 @@ fish_color_comment f7ca88
 fish_color_cwd green
 fish_color_cwd_root red
 fish_color_end ba8baf
-fish_color_error ab4642
+fish_color_error ab4642 --underline=curly
 fish_color_escape 86c1b9
 fish_color_history_current --bold
 fish_color_host normal
--- a/share/tools/web_config/themes/Base16
+++ b/share/tools/web_config/themes/Base16
@@ -10,7 +10,7 @@ fish_color_comment f7ca88
 fish_color_cwd green
 fish_color_cwd_root red
 fish_color_end ba8baf
-fish_color_error ab4642
+fish_color_error ab4642 --underline=curly
 fish_color_escape 86c1b9
 fish_color_history_current --bold
 fish_color_host normal
--- a/share/tools/web_config/themes/Base16
+++ b/share/tools/web_config/themes/Base16
@@ -10,7 +10,7 @@ fish_color_comment ffcc66
 fish_color_cwd green
 fish_color_cwd_root red
 fish_color_end cc99cc
-fish_color_error f2777a
+fish_color_error f2777a --underline=curly
 fish_color_escape 66cccc
 fish_color_history_current --bold
 fish_color_host normal
--- a/share/tools/web_config/themes/Bay
+++ b/share/tools/web_config/themes/Bay
@@ -9,7 +9,7 @@ fish_color_comment FF9640
 fish_color_cwd green
 fish_color_cwd_root red
 fish_color_end FFB273
-fish_color_error FF7400
+fish_color_error FF7400 --underline=curly
 fish_color_escape 00a6b2
 fish_color_history_current --bold
 fish_color_host normal
--- a/share/tools/web_config/themes/Dracula.theme
+++ b/share/tools/web_config/themes/Dracula.theme
@@ -21,7 +21,7 @@ fish_color_comment 6272a4
 fish_color_cwd 50fa7b
 fish_color_cwd_root red
 fish_color_end ffb86c
-fish_color_error ff5555
+fish_color_error ff5555 --underline=curly
 fish_color_escape ff79c6
 fish_color_history_current --bold
 fish_color_host bd93f9
--- a/share/tools/web_config/themes/Fairground.theme
+++ b/share/tools/web_config/themes/Fairground.theme
@@ -9,7 +9,7 @@ fish_color_comment FFE100
 fish_color_cwd green
 fish_color_cwd_root red
 fish_color_end 8D003B
-fish_color_error EC3B86
+fish_color_error EC3B86 --underline=curly
 fish_color_escape 00a6b2
 fish_color_history_current --bold
 fish_color_host normal
--- a/share/tools/web_config/themes/Just
+++ b/share/tools/web_config/themes/Just
@@ -9,7 +9,7 @@ fish_color_comment B0B0B0
 fish_color_cwd green
 fish_color_cwd_root red
 fish_color_end 969696
-fish_color_error FFA779
+fish_color_error FFA779 --underline=curly
 fish_color_escape 00a6b2
 fish_color_history_current --bold
 fish_color_host normal
--- a/share/tools/web_config/themes/Lava.theme
+++ b/share/tools/web_config/themes/Lava.theme
@@ -6,7 +6,7 @@ fish_color_command FF9400
 fish_color_quote BF9C30
 fish_color_redirection BF5B30
 fish_color_end FF4C00
-fish_color_error FFDD73
+fish_color_error FFDD73 --underline=curly
 fish_color_param FFC000
 fish_color_comment A63100
 fish_color_selection white --background=brblack --bold
--- a/share/tools/web_config/themes/Mono
+++ b/share/tools/web_config/themes/Mono
@@ -9,7 +9,7 @@ fish_color_comment 4e4e4e
 fish_color_cwd green
 fish_color_cwd_root red
 fish_color_end 767676
-fish_color_error b2b2b2
+fish_color_error b2b2b2 --underline=curly
 fish_color_escape 00a6b2
 fish_color_history_current --bold
 fish_color_host normal
--- a/share/tools/web_config/themes/Mono
+++ b/share/tools/web_config/themes/Mono
@@ -6,7 +6,7 @@ fish_color_command ffffff
 fish_color_quote a8a8a8
 fish_color_redirection 808080
 fish_color_end 949494
-fish_color_error 585858
+fish_color_error 585858 --underline=curly
 fish_color_param d7d7d7
 fish_color_comment bcbcbc
 fish_color_selection white --background=brblack --bold
--- a/share/tools/web_config/themes/None.theme
+++ b/share/tools/web_config/themes/None.theme
@@ -9,7 +9,7 @@ fish_color_comment
 fish_color_cwd normal
 fish_color_cwd_root normal
 fish_color_end
-fish_color_error
+fish_color_error --underline=curly
 fish_color_escape
 fish_color_history_current
 fish_color_host normal
--- a/share/tools/web_config/themes/Nord.theme
+++ b/share/tools/web_config/themes/Nord.theme
@@ -11,7 +11,7 @@ fish_color_comment 4c566a --italics
 fish_color_cwd 5e81ac
 fish_color_cwd_root bf616a
 fish_color_end 81a1c1
-fish_color_error bf616a
+fish_color_error bf616a --underline=curly
 fish_color_escape ebcb8b
 fish_color_history_current e5e9f0 --bold
 fish_color_host a3be8c
--- a/share/tools/web_config/themes/Old
+++ b/share/tools/web_config/themes/Old
@@ -9,7 +9,7 @@ fish_color_comment 30BE30
 fish_color_cwd green
 fish_color_cwd_root red
 fish_color_end FF7B7B
-fish_color_error A40000
+fish_color_error A40000 --underline=curly
 fish_color_escape 00a6b2
 fish_color_history_current --bold
 fish_color_host normal
--- a/share/tools/web_config/themes/Seaweed.theme
+++ b/share/tools/web_config/themes/Seaweed.theme
@@ -9,7 +9,7 @@ fish_color_comment 5C9900
 fish_color_cwd green
 fish_color_cwd_root red
 fish_color_end 8EEB00
-fish_color_error 60B9CE
+fish_color_error 60B9CE --underline=curly
 fish_color_escape 00a6b2
 fish_color_history_current --bold
 fish_color_host normal
--- a/share/tools/web_config/themes/Snow
+++ b/share/tools/web_config/themes/Snow
@@ -6,7 +6,7 @@ fish_color_command 164CC9
 fish_color_quote 4C3499
 fish_color_redirection 248E8E
 fish_color_end 02BDBD
-fish_color_error 9177E5
+fish_color_error 9177E5 --underline=curly
 fish_color_param 4319CC
 fish_color_comment 007B7B
 fish_color_selection white --background=brblack --bold
--- a/share/tools/web_config/themes/Solarized
+++ b/share/tools/web_config/themes/Solarized
@@ -10,7 +10,7 @@ fish_color_comment 586e75
 fish_color_cwd green
 fish_color_cwd_root red
 fish_color_end 268bd2
-fish_color_error dc322f
+fish_color_error dc322f --underline=curly
 fish_color_escape 00a6b2
 fish_color_history_current --bold
 fish_color_host normal
--- a/share/tools/web_config/themes/Solarized
+++ b/share/tools/web_config/themes/Solarized
@@ -7,7 +7,7 @@ fish_color_command 586e75
 fish_color_quote 839496
 fish_color_redirection 6c71c4
 fish_color_end 268bd2
-fish_color_error dc322f
+fish_color_error dc322f --underline=curly
 fish_color_param 657b83
 fish_color_comment 93a1a1
 fish_color_selection white --background=brblack --bold
--- a/share/tools/web_config/themes/Tomorrow
+++ b/share/tools/web_config/themes/Tomorrow
@@ -10,7 +10,7 @@ fish_color_comment e7c547
 fish_color_cwd green
 fish_color_cwd_root red
 fish_color_end c397d8
-fish_color_error d54e53
+fish_color_error d54e53 --underline=curly
 fish_color_escape 00a6b2
 fish_color_history_current --bold
 fish_color_host normal
--- a/share/tools/web_config/themes/Tomorrow
+++ b/share/tools/web_config/themes/Tomorrow
@@ -7,7 +7,7 @@ fish_color_command b294bb
 fish_color_quote b5bd68
 fish_color_redirection 8abeb7
 fish_color_end b294bb
-fish_color_error cc6666
+fish_color_error cc6666 --underline=curly
 fish_color_param 81a2be
 fish_color_comment f0c674
 fish_color_selection white --background=brblack --bold
--- a/share/tools/web_config/themes/Tomorrow.theme
+++ b/share/tools/web_config/themes/Tomorrow.theme
@@ -10,7 +10,7 @@ fish_color_comment eab700
 fish_color_cwd green
 fish_color_cwd_root red
 fish_color_end 8959a8
-fish_color_error c82829
+fish_color_error c82829 --underline=curly
 fish_color_escape 00a6b2
 fish_color_history_current --bold
 fish_color_host normal
--- a/share/tools/web_config/themes/ayu
+++ b/share/tools/web_config/themes/ayu
@@ -7,7 +7,7 @@ fish_color_command 39BAE6
 fish_color_quote C2D94C
 fish_color_redirection FFEE99
 fish_color_end F29668
-fish_color_error FF3333
+fish_color_error FF3333 --underline=curly
 fish_color_param B3B1AD
 fish_color_comment 626A73
 fish_color_selection --background=E6B450 --bold
--- a/share/tools/web_config/themes/ayu
+++ b/share/tools/web_config/themes/ayu
@@ -10,7 +10,7 @@ fish_color_comment ABB0B6
 fish_color_cwd 399EE6
 fish_color_cwd_root red
 fish_color_end ED9366
-fish_color_error F51818
+fish_color_error F51818 --underline=curly
 fish_color_escape 4CBF99
 fish_color_history_current --bold
 fish_color_host normal
--- a/share/tools/web_config/themes/ayu
+++ b/share/tools/web_config/themes/ayu
@@ -10,7 +10,7 @@ fish_color_comment 5C6773
 fish_color_cwd 73D0FF
 fish_color_cwd_root red
 fish_color_end F29E74
-fish_color_error FF3333
+fish_color_error FF3333 --underline=curly
 fish_color_escape 95E6CB
 fish_color_history_current --bold
 fish_color_host normal
--- a/share/tools/web_config/themes/coolbeans.theme
+++ b/share/tools/web_config/themes/coolbeans.theme
@@ -9,7 +9,7 @@ fish_color_comment '888'  '--italics'
 fish_color_cwd 0A0
 fish_color_cwd_root A00
 fish_color_end 009900
-fish_color_error F22
+fish_color_error F22 --underline=curly
 fish_color_escape 0AA
 fish_color_history_current 0AA
 fish_color_host normal
--- a/share/tools/web_config/themes/fish
+++ b/share/tools/web_config/themes/fish
@@ -11,7 +11,7 @@ fish_color_comment red
 fish_color_cwd green
 fish_color_cwd_root red
 fish_color_end green
-fish_color_error brred
+fish_color_error brred --underline=curly
 fish_color_escape brcyan
 fish_color_history_current --bold
 fish_color_host normal
--- a/tests/checks/fish_config.fish
+++ b/tests/checks/fish_config.fish
@@ -1,7 +1,10 @@
 #RUN: %fish %s

 mkdir $__fish_config_dir/themes
-echo >$__fish_config_dir/themes/foo.theme 'fish_color_normal cyan'
+echo >$__fish_config_dir/themes/foo.theme '
+fish_color_normal cyan
+fish_color_error brred --underline=curly
+'

 set -g fish_pager_color_secondary_background custom-value
 fish_config theme choose foo
@@ -12,6 +15,14 @@ set -S fish_color_normal
 set -S fish_pager_color_secondary_background
 # CHECK: $fish_pager_color_secondary_background: set in global scope, unexported, with 0 elements

+# Not a default theme, so we allow --underline=curly even if we don't run inside a terminal that
+# advertises support via XTGETTCAP.
+set -S fish_color_error
+# CHECK: $fish_color_error: set in global scope, unexported, with 2 elements
+# CHECK: $fish_color_error[1]: |brred|
+# CHECK: $fish_color_error[2]: |--underline=curly|
+
+
 function change-theme
    echo >$__fish_config_dir/themes/fake-default.theme 'fish_color_command' $argv
 end