git-gui: Refactor our ui_status_value update technique

I'm really starting to dislike global variables.  The ui_status_value
global varible is just one of those that seems to appear in a lot of
code and in many cases we didn't even declare it "global" within the
proc that updates it so we haven't always been getting all of the
updates we expected to see.

This change introduces two new global procs:

  ui_status $msg;   # Sets the status bar to show $msg.
  ui_ready;         # Changes the status bar to show "Ready."

The second (special) form is used because we often update the area
with this message once we are done processing a block of work and
want the user to know we have completed it.

I'm not fixing the cases that appear in lib/branch.tcl right now
as I'm actually in the middle of a huge refactoring of that code
to support making a detached HEAD checkout.

Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

git-gui.sh

@@ -527,7 +527,7 @@ proc PARENT {} {
 
 proc rescan {after {honor_trustmtime 1}} {
 	global HEAD PARENT MERGE_HEAD commit_type
-	global ui_index ui_workdir ui_status_value ui_comm
+	global ui_index ui_workdir ui_comm
 	global rescan_active file_states
 	global repo_config
 
@@ -566,7 +566,7 @@ proc rescan {after {honor_trustmtime 1}} {
 		rescan_stage2 {} $after
 	} else {
 		set rescan_active 1
-		set ui_status_value {Refreshing file status...}
+		ui_status {Refreshing file status...}
 		set cmd [list git update-index]
 		lappend cmd -q
 		lappend cmd --unmerged
@@ -580,7 +580,6 @@ proc rescan {after {honor_trustmtime 1}} {
 }
 
 proc rescan_stage2 {fd after} {
-	global ui_status_value
 	global rescan_active buf_rdi buf_rdf buf_rlo
 
 	if {$fd ne {}} {
@@ -601,7 +600,7 @@ proc rescan_stage2 {fd after} {
 	set buf_rlo {}
 
 	set rescan_active 3
-	set ui_status_value {Scanning for modified files ...}
+	ui_status {Scanning for modified files ...}
 	set fd_di [open "| git diff-index --cached -z [PARENT]" r]
 	set fd_df [open "| git diff-files -z" r]
 	set fd_lo [open $ls_others r]
@@ -761,6 +760,16 @@ proc mapdesc {state path} {
 	return $r
 }
 
+proc ui_status {msg} {
+	set ::ui_status_value $msg
+}
+
+proc ui_ready {{test {}}} {
+	if {$test eq {} || $::ui_status_value eq $test} {
+		ui_status Ready.
+	}
+}
+
 proc escape_path {path} {
 	regsub -all {\\} $path "\\\\" path
 	regsub -all "\n" $path "\\n" path
@@ -1112,7 +1121,7 @@ proc incr_font_size {font {amt 1}} {
 set starting_gitk_msg {Starting gitk... please wait...}
 
 proc do_gitk {revs} {
-	global env ui_status_value starting_gitk_msg
+	global env starting_gitk_msg
 
 	# -- Always start gitk through whatever we were loaded with.  This
 	#    lets us bypass using shell process on Windows systems.
@@ -1129,11 +1138,9 @@ proc do_gitk {revs} {
 		error_popup "Unable to start gitk:\n\n$exe does not exist"
 	} else {
 		eval exec $cmd &
-		set ui_status_value $starting_gitk_msg
+		ui_status $starting_gitk_msg
 		after 10000 {
-			if {$ui_status_value eq $starting_gitk_msg} {
-				set ui_status_value {Ready.}
-			}
+			ui_ready $starting_gitk_msg
 		}
 	}
 }
@@ -1182,7 +1189,7 @@ proc do_quit {} {
 }
 
 proc do_rescan {} {
-	rescan {set ui_status_value {Ready.}}
+	rescan ui_ready
 }
 
 proc do_commit {} {
@@ -1217,12 +1224,12 @@ proc toggle_or_diff {w x y} {
 			update_indexinfo \
 				"Unstaging [short_path $path] from commit" \
 				[list $path] \
-				[concat $after {set ui_status_value {Ready.}}]
+				[concat $after [list ui_ready]]
 		} elseif {$w eq $ui_workdir} {
 			update_index \
 				"Adding [short_path $path]" \
 				[list $path] \
-				[concat $after {set ui_status_value {Ready.}}]
+				[concat $after [list ui_ready]]
 		}
 	} else {
 		show_diff $path $w $lno
@@ -1640,20 +1647,19 @@ if {[is_MacOSX]} {
 	#
 	if {[is_Cygwin] && [file exists /usr/local/miga/lib/gui-miga]} {
 	proc do_miga {} {
-		global ui_status_value
 		if {![lock_index update]} return
 		set cmd [list sh --login -c "/usr/local/miga/lib/gui-miga \"[pwd]\""]
 		set miga_fd [open "|$cmd" r]
 		fconfigure $miga_fd -blocking 0
 		fileevent $miga_fd readable [list miga_done $miga_fd]
-		set ui_status_value {Running miga...}
+		ui_status {Running miga...}
 	}
 	proc miga_done {fd} {
 		read $fd 512
 		if {[eof $fd]} {
 			close $fd
 			unlock_index
-			rescan [list set ui_status_value {Ready.}]
+			rescan ui_ready
 		}
 	}
 	.mbar add cascade -label Tools -menu .mbar.tools

lib/commit.tcl

@@ -58,7 +58,7 @@ You are currently in the middle of a merge that has not been fully completed.  Y
 	$ui_comm insert end $msg
 	$ui_comm edit reset
 	$ui_comm edit modified false
-	rescan {set ui_status_value {Ready.}}
+	rescan ui_ready
 }
 
 set GIT_COMMITTER_IDENT {}
@@ -108,12 +108,12 @@ proc create_new_commit {} {
 	$ui_comm delete 0.0 end
 	$ui_comm edit reset
 	$ui_comm edit modified false
-	rescan {set ui_status_value {Ready.}}
+	rescan ui_ready
 }
 
 proc commit_tree {} {
 	global HEAD commit_type file_states ui_comm repo_config
-	global ui_status_value pch_error
+	global pch_error
 
 	if {[committer_ident] eq {}} return
 	if {![lock_index update]} return
@@ -132,7 +132,7 @@ Another Git program has modified this repository since the last scan.  A rescan
 The rescan will be automatically started now.
 }
 		unlock_index
-		rescan {set ui_status_value {Ready.}}
+		rescan ui_ready
 		return
 	}
 
@@ -206,7 +206,7 @@ A good commit message has the following format:
 		return
 	}
 
-	set ui_status_value {Calling pre-commit hook...}
+	ui_status {Calling pre-commit hook...}
 	set pch_error {}
 	set fd_ph [open "| $pchook" r]
 	fconfigure $fd_ph -blocking 0 -translation binary
@@ -215,13 +215,13 @@ A good commit message has the following format:
 }
 
 proc commit_prehook_wait {fd_ph curHEAD msg} {
-	global pch_error ui_status_value
+	global pch_error
 
 	append pch_error [read $fd_ph]
 	fconfigure $fd_ph -blocking 1
 	if {[eof $fd_ph]} {
 		if {[catch {close $fd_ph}]} {
-			set ui_status_value {Commit declined by pre-commit hook.}
+			ui_status {Commit declined by pre-commit hook.}
 			hook_failed_popup pre-commit $pch_error
 			unlock_index
 		} else {
@@ -234,9 +234,7 @@ proc commit_prehook_wait {fd_ph curHEAD msg} {
 }
 
 proc commit_writetree {curHEAD msg} {
-	global ui_status_value
-
-	set ui_status_value {Committing changes...}
+	ui_status {Committing changes...}
 	set fd_wt [open "| git write-tree" r]
 	fileevent $fd_wt readable \
 		[list commit_committree $fd_wt $curHEAD $msg]
@@ -244,15 +242,15 @@ proc commit_writetree {curHEAD msg} {
 
 proc commit_committree {fd_wt curHEAD msg} {
 	global HEAD PARENT MERGE_HEAD commit_type
-	global all_heads current_branch
-	global ui_status_value ui_comm selected_commit_type
+	global current_branch
+	global ui_comm selected_commit_type
 	global file_states selected_paths rescan_active
 	global repo_config
 
 	gets $fd_wt tree_id
 	if {$tree_id eq {} || [catch {close $fd_wt} err]} {
 		error_popup "write-tree failed:\n\n$err"
-		set ui_status_value {Commit failed.}
+		ui_status {Commit failed.}
 		unlock_index
 		return
 	}
@@ -269,7 +267,7 @@ No files were modified by this commit and it was not a merge commit.
 A rescan will be automatically started now.
 }
 			unlock_index
-			rescan {set ui_status_value {No changes to commit.}}
+			rescan {ui_status {No changes to commit.}}
 			return
 		}
 	}
@@ -294,7 +292,7 @@ A rescan will be automatically started now.
 	lappend cmd <$msg_p
 	if {[catch {set cmt_id [eval git $cmd]} err]} {
 		error_popup "commit-tree failed:\n\n$err"
-		set ui_status_value {Commit failed.}
+		ui_status {Commit failed.}
 		unlock_index
 		return
 	}
@@ -316,7 +314,7 @@ A rescan will be automatically started now.
 			git update-ref -m $reflogm HEAD $cmt_id $curHEAD
 		} err]} {
 		error_popup "update-ref failed:\n\n$err"
-		set ui_status_value {Commit failed.}
+		ui_status {Commit failed.}
 		unlock_index
 		return
 	}
@@ -410,6 +408,5 @@ A rescan will be automatically started now.
 	display_all_files
 	unlock_index
 	reshow_diff
-	set ui_status_value \
-		"Created commit [string range $cmt_id 0 7]: $subject"
+	ui_status "Created commit [string range $cmt_id 0 7]: $subject"
 }

lib/diff.tcl

@@ -17,7 +17,7 @@ proc clear_diff {} {
 }
 
 proc reshow_diff {} {
-	global ui_status_value file_states file_lists
+	global file_states file_lists
 	global current_diff_path current_diff_side
 
 	set p $current_diff_path
@@ -49,13 +49,13 @@ A rescan will be automatically started to find other files which may have the sa
 
 	clear_diff
 	display_file $path __
-	rescan {set ui_status_value {Ready.}} 0
+	rescan ui_ready 0
 }
 
 proc show_diff {path w {lno {}}} {
 	global file_states file_lists
 	global is_3way_diff diff_active repo_config
-	global ui_diff ui_status_value ui_index ui_workdir
+	global ui_diff ui_index ui_workdir
 	global current_diff_path current_diff_side current_diff_header
 
 	if {$diff_active || ![lock_index read]} return
@@ -78,7 +78,7 @@ proc show_diff {path w {lno {}}} {
 	set current_diff_path $path
 	set current_diff_side $w
 	set current_diff_header {}
-	set ui_status_value "Loading diff of [escape_path $path]..."
+	ui_status "Loading diff of [escape_path $path]..."
 
 	# - Git won't give us the diff, there's nothing to compare to!
 	#
@@ -92,7 +92,7 @@ proc show_diff {path w {lno {}}} {
 			} err ]} {
 			set diff_active 0
 			unlock_index
-			set ui_status_value "Unable to display [escape_path $path]"
+			ui_status "Unable to display [escape_path $path]"
 			error_popup "Error loading file:\n\n$err"
 			return
 		}
@@ -127,7 +127,7 @@ proc show_diff {path w {lno {}}} {
 		$ui_diff conf -state disabled
 		set diff_active 0
 		unlock_index
-		set ui_status_value {Ready.}
+		ui_ready
 		return
 	}
 
@@ -157,7 +157,7 @@ proc show_diff {path w {lno {}}} {
 	if {[catch {set fd [open $cmd r]} err]} {
 		set diff_active 0
 		unlock_index
-		set ui_status_value "Unable to display [escape_path $path]"
+		ui_status "Unable to display [escape_path $path]"
 		error_popup "Error loading diff:\n\n$err"
 		return
 	}
@@ -170,7 +170,7 @@ proc show_diff {path w {lno {}}} {
 }
 
 proc read_diff {fd} {
-	global ui_diff ui_status_value diff_active
+	global ui_diff diff_active
 	global is_3way_diff current_diff_header
 
 	$ui_diff conf -state normal
@@ -256,7 +256,7 @@ proc read_diff {fd} {
 		close $fd
 		set diff_active 0
 		unlock_index
-		set ui_status_value {Ready.}
+		ui_ready
 
 		if {[$ui_diff index end] eq {2.0}} {
 			handle_empty_diff

lib/index.tcl

@@ -2,7 +2,7 @@
 # Copyright (C) 2006, 2007 Shawn Pearce
 
 proc update_indexinfo {msg pathList after} {
-	global update_index_cp ui_status_value
+	global update_index_cp
 
 	if {![lock_index update]} return
 
@@ -12,7 +12,7 @@ proc update_indexinfo {msg pathList after} {
 	set batch [expr {int($totalCnt * .01) + 1}]
 	if {$batch > 25} {set batch 25}
 
-	set ui_status_value [format \
+	ui_status [format \
 		"$msg... %i/%i files (%.2f%%)" \
 		$update_index_cp \
 		$totalCnt \
@@ -36,7 +36,7 @@ proc update_indexinfo {msg pathList after} {
 }
 
 proc write_update_indexinfo {fd pathList totalCnt batch msg after} {
-	global update_index_cp ui_status_value
+	global update_index_cp
 	global file_states current_diff_path
 
 	if {$update_index_cp >= $totalCnt} {
@@ -67,7 +67,7 @@ proc write_update_indexinfo {fd pathList totalCnt batch msg after} {
 		display_file $path $new
 	}
 
-	set ui_status_value [format \
+	ui_status [format \
 		"$msg... %i/%i files (%.2f%%)" \
 		$update_index_cp \
 		$totalCnt \
@@ -75,7 +75,7 @@ proc write_update_indexinfo {fd pathList totalCnt batch msg after} {
 }
 
 proc update_index {msg pathList after} {
-	global update_index_cp ui_status_value
+	global update_index_cp
 
 	if {![lock_index update]} return
 
@@ -85,7 +85,7 @@ proc update_index {msg pathList after} {
 	set batch [expr {int($totalCnt * .01) + 1}]
 	if {$batch > 25} {set batch 25}
 
-	set ui_status_value [format \
+	ui_status [format \
 		"$msg... %i/%i files (%.2f%%)" \
 		$update_index_cp \
 		$totalCnt \
@@ -109,7 +109,7 @@ proc update_index {msg pathList after} {
 }
 
 proc write_update_index {fd pathList totalCnt batch msg after} {
-	global update_index_cp ui_status_value
+	global update_index_cp
 	global file_states current_diff_path
 
 	if {$update_index_cp >= $totalCnt} {
@@ -144,7 +144,7 @@ proc write_update_index {fd pathList totalCnt batch msg after} {
 		display_file $path $new
 	}
 
-	set ui_status_value [format \
+	ui_status [format \
 		"$msg... %i/%i files (%.2f%%)" \
 		$update_index_cp \
 		$totalCnt \
@@ -152,7 +152,7 @@ proc write_update_index {fd pathList totalCnt batch msg after} {
 }
 
 proc checkout_index {msg pathList after} {
-	global update_index_cp ui_status_value
+	global update_index_cp
 
 	if {![lock_index update]} return
 
@@ -162,7 +162,7 @@ proc checkout_index {msg pathList after} {
 	set batch [expr {int($totalCnt * .01) + 1}]
 	if {$batch > 25} {set batch 25}
 
-	set ui_status_value [format \
+	ui_status [format \
 		"$msg... %i/%i files (%.2f%%)" \
 		$update_index_cp \
 		$totalCnt \
@@ -192,7 +192,7 @@ proc checkout_index {msg pathList after} {
 }
 
 proc write_checkout_index {fd pathList totalCnt batch msg after} {
-	global update_index_cp ui_status_value
+	global update_index_cp
 	global file_states current_diff_path
 
 	if {$update_index_cp >= $totalCnt} {
@@ -217,7 +217,7 @@ proc write_checkout_index {fd pathList totalCnt batch msg after} {
 		}
 	}
 
-	set ui_status_value [format \
+	ui_status [format \
 		"$msg... %i/%i files (%.2f%%)" \
 		$update_index_cp \
 		$totalCnt \
@@ -249,7 +249,7 @@ proc unstage_helper {txt paths} {
 		update_indexinfo \
 			$txt \
 			$pathList \
-			[concat $after {set ui_status_value {Ready.}}]
+			[concat $after [list ui_ready]]
 	}
 }
 
@@ -293,7 +293,7 @@ proc add_helper {txt paths} {
 		update_index \
 			$txt \
 			$pathList \
-			[concat $after {set ui_status_value {Ready to commit.}}]
+			[concat $after {ui_status {Ready to commit.}}]
 	}
 }
 
@@ -370,7 +370,7 @@ Any unadded changes will be permanently lost by the revert." \
 		checkout_index \
 			$txt \
 			$pathList \
-			[concat $after {set ui_status_value {Ready.}}]
+			[concat $after [list ui_ready]]
 	} else {
 		unlock_index
 	}

lib/merge.tcl

@@ -28,7 +28,7 @@ Another Git program has modified this repository since the last scan.  A rescan
 The rescan will be automatically started now.
 }
 		unlock_index
-		rescan {set ui_status_value {Ready.}}
+		rescan ui_ready
 		return 0
 	}
 
@@ -79,7 +79,7 @@ proc _visualize {w list} {
 }
 
 proc _start {w list} {
-	global HEAD ui_status_value current_branch
+	global HEAD current_branch
 
 	set cmd [list git merge]
 	set names [_refs $w $list]
@@ -121,7 +121,7 @@ Please select fewer branches.  To merge more than 15 branches, merge the branche
 	}
 
 	set msg "Merging $current_branch, [join $names {, }]"
-	set ui_status_value "$msg..."
+	ui_status "$msg..."
 	set cons [console::new "Merge" $msg]
 	console::exec $cons $cmd \
 		[namespace code [list _finish $revcnt $cons]]
@@ -150,14 +150,14 @@ You can attempt this merge again by merging only one branch at a time." $w
 			fconfigure $fd -blocking 0 -translation binary
 			fileevent $fd readable \
 				[namespace code [list _reset_wait $fd]]
-			set ui_status_value {Aborting... please wait...}
+			ui_status {Aborting... please wait...}
 			return
 		}
 
 		set msg {Merge failed.  Conflict resolution is required.}
 	}
 	unlock_index
-	rescan [list set ui_status_value $msg]
+	rescan [list ui_status $msg]
 }
 
 proc dialog {} {
@@ -285,7 +285,7 @@ Continue with aborting the current $op?"] eq {yes}} {
 		set fd [open "| git read-tree --reset -u HEAD" r]
 		fconfigure $fd -blocking 0 -translation binary
 		fileevent $fd readable [namespace code [list _reset_wait $fd]]
-		set ui_status_value {Aborting... please wait...}
+		ui_status {Aborting... please wait...}
 	} else {
 		unlock_index
 	}
@@ -308,7 +308,7 @@ proc _reset_wait {fd} {
 		catch {file delete [gitdir MERGE_MSG]}
 		catch {file delete [gitdir GITGUI_MSG]}
 
-		rescan {set ui_status_value {Abort completed.  Ready.}}
+		rescan {ui_status {Abort completed.  Ready.}}
 	}
 }