git-gui: add support for filenames starting with tilde

From: =?UTF-8?q?Matthias=20A=C3=9Fhauer?= <[email protected]>

When git-gui encounters a file name starting with a tilde character (~), TCL "helpfully" expands that tilde into a (probably non-existing) users home directory. But in git-gui we're often not dealing with user supplied paths, where such an expansion might be expected, but actual names of files.

Prevent TCL from doing tilde expansion on these literal filenames.

This fixes https://github.com/git-for-windows/git/issues/4349

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git-gui: add support for filenames starting with tilde

I've originally submitted this patch as a pull request to Pratyush's git-gui repository [1] on March 23rd, but that hasn't received any feedback in almost seven months, so I'm resubmitting it on the mailing list, with an improved patch description.

[1] https://github.com/prati0100/git-gui/pull/96

Published-As: https://github.com/gitgitgadget/git/releases/tag/pr-1599%2Frimrul%2Fgit-gui-tilde-filenames-v1
Fetch-It-Via: git fetch https://github.com/gitgitgadget/git pr-1599/rimrul/git-gui-tilde-filenames-v1
Pull-Request: https://github.com/gitgitgadget/git/pull/1599

 git-gui/git-gui.sh    | 1 +
 git-gui/lib/diff.tcl  | 1 +
 git-gui/lib/index.tcl | 2 +-
 3 files changed, 3 insertions(+), 1 deletion(-)

index 3e5907a4609..e8d60cf3324 100755
@@ -2273,6 +2273,7 @@ proc do_explore {} {
 # Open file relative to the working tree by the default associated app.
 proc do_file_open {file} {
 	global _gitworktree
+	if {[string index $file 0] eq {~}} {set file ./$file}
 	set explorer [get_explorer]
 	set full_file_path [file join $_gitworktree $file]
 	exec $explorer [file nativename $full_file_path] &

index 871ad488c2a..b7686caa962 100644
@@ -190,6 +190,7 @@ proc show_other_diff {path w m cont_info} {
 		set max_sz 100000
 		set type unknown
 		if {[catch {
+				if {[string index $path 0] eq {~}} {set path ./$path}
 				set type [file type $path]
 				switch -- $type {
 				directory {

index d2ec24bd80e..2fbe1447975 100644
@@ -617,7 +617,7 @@ proc delete_helper {path_list path_index deletion_errors batch_size \
 
 		set path [lindex $path_list $path_index]
 
-		set deletion_failed [catch {file delete -- $path} deletion_error]
+		set deletion_failed [catch {file delete -- ./$path} deletion_error]
 
 		if {$deletion_failed} {
 			lappend deletion_errors [list "$deletion_error"]

base-commit: a9ecda2788e229afc9b611acaa26d0d9d4da53ed

gitgitgadget

I do not have stake in git-gui (or gitk) and take the changes the subsystem owners have decided to take from them, but I have to wonder if this is merely robbing Peter to pay Paul?

If the above description were not "we're often not" but "the only paths we use are repository relative, and a path that begin with a tilde NEVER refers to somebody's home directory", then I would buy into the change (but again, I am not even a user of git-gui, so take this with a moderate grains of salt).

Thanks.