git-gui: remove HEAD detachment implementation for git < 1.5.3

git-gui provides an implementation to detach HEAD on Git versions prior
to 1.5.3.  Nobody should be using such an old version anymore.
(Moreover, since 0730a5a3a, git-gui requires git v2.36 or later).
Keep only the code for modern Git.

Signed-off-by: Mark Levedahl <mlevedahl@gmail.com>
[j6t: message tweaked]
Signed-off-by: Johannes Sixt <j6t@kdbg.org>
Signed-off-by: Taylor Blau <me@ttaylorr.com>

diff --git a/lib/checkout_op.tcl b/lib/checkout_op.tcl
index 21ea768d8036c0ae2ba6bd430c6c667b5ac30c4f..5f7011078abbcf96a61e30eb1049c1b4d0a26a43 100644 (file)
--- a/lib/checkout_op.tcl
+++ b/lib/checkout_op.tcl
@@ -510,18 +510,8 @@ method _update_repo_state {} {
        delete_this
 }
 
-git-version proc _detach_HEAD {log new} {
-       >= 1.5.3 {
-               git update-ref --no-deref -m $log HEAD $new
-       }
-       default {
-               set p [gitdir HEAD]
-               file delete $p
-               set fd [open $p w]
-               fconfigure $fd -translation lf -encoding utf-8
-               puts $fd $new
-               close $fd
-       }
+proc _detach_HEAD {log new} {
+       git update-ref --no-deref -m $log HEAD $new
 }
 
 method _confirm_reset {cur} {