[PATCH v1 11/11] git-gui: add gui and pick as explicit subcommands

[Mark Levedahl <mlevedahl@gmail.com>]

git-gui accepts subcommands blame | browser | citool, and assumes the
subcommand is 'gui' if none is actually given, But, git gui also has a
repository picker (choose_repository::pick) that can create a new
repository + worktree, or choose an existing one, switch to that, and
the run the gui. The user has no direct control over invoking the
picker, instead the picker is triggered by failure in the repository /
worktree discover process: this includes being started in a directory
not controlled by git, which is probably the intended use case.

The picker can appear when the user has no intention of creating a new
worktree, and the user cannot use the picker to create a new worktree
inside another.

So, add two new explicit subcommands:
    gui  - Run the gui if repository/worktree discovery succeeds, or die
           with an error message, but never run the picker.
    pick - First run the picker, regardless, then start the gui in
           the chosen worktree.

Nothing in this changes the prior behavior, the alternates above must be
explicitly selected to see any change.

Signed-off-by: Mark Levedahl <mlevedahl@gmail.com>
---
 git-gui.sh | 22 ++++++++++++++++++++--
 1 file changed, 20 insertions(+), 2 deletions(-)

diff --git a/git-gui.sh b/git-gui.sh
index 3a83dd5..c56aeef 100755
--- a/git-gui.sh
+++ b/git-gui.sh
@@ -1021,6 +1021,7 @@ proc load_config {include_global} {
 ##
 ## feature option selection
 
+set run_picker_on_error 1
 if {[regexp {^git-(.+)$} [file tail $argv0] _junk subcommand]} {
 	unset _junk
 } else {
@@ -1030,6 +1031,7 @@ if {$subcommand eq {gui.sh}} {
 	set subcommand gui
 }
 if {$subcommand eq {gui} && [llength $argv] > 0} {
+	set run_picker_on_error 0
 	set subcommand [lindex $argv 0]
 	set argv [lrange $argv 1 end]
 }
@@ -1047,6 +1049,7 @@ blame {
 	disable_option multicommit
 	disable_option branch
 	disable_option transport
+	set run_picker_on_error 0
 }
 citool {
 	enable_option singlecommit
@@ -1055,6 +1058,7 @@ citool {
 	disable_option multicommit
 	disable_option branch
 	disable_option transport
+	set run_picker_on_error 0
 
 	while {[llength $argv] > 0} {
 		set a [lindex $argv 0]
@@ -1162,14 +1166,28 @@ proc pick_repo {} {
 	set picked 1
 }
 
+# run repository picker if explicitly requested
+switch -- $subcommand {
+	pick {
+		pick_repo
+		set subcommand gui
+		set run_picker_on_error 0
+	}
+}
+
 # find repository.
 if {[catch {
 	set _gitdir [git rev-parse --absolute-git-dir]
 } err]} {
 	if {[is_gitvars_error $err]} {
 		exit 1
-	} else {
+	}
+	if {$run_picker_on_error} {
 		pick_repo
+	} else {
+		catch {wm withdraw .}
+		error_popup [strcat [mc "Git directory not found:"] "\n\n$err"]
+		exit 1
 	}
 }
 
@@ -3051,7 +3069,7 @@ gui {
 	# fall through to setup UI for commits
 }
 default {
-	set err "[mc usage:] $argv0 \[{blame|browser|citool}\]"
+	set err "[mc usage:] $argv0 \[{blame|browser|citool|gui|pick}\]"
 	if {[tk windowingsystem] eq "win32"} {
 		wm withdraw .
 		tk_messageBox -icon error -message $err \
-- 
2.54.0.99.14