Merge updated git-gui and gitk that call each other

Merge git://repo.or.cz/git-gui and git://git.kernel.org/pub/scm/gitk/gitk

    * git://repo.or.cz/git-gui:
      git-gui: Show special diffs for complex conflict cases.
      git-gui: Make F5 reselect a diff, if an untracked file is selected.
      git-gui: Reimplement and enhance auto-selection of diffs.
      git-gui: Support conflict states _U & UT.
      git-gui: Support more merge tools.
      git-gui: Don't allow staging files with conflicts.
      git-gui: Support calling merge tools.
      git-gui: Support resolving conflicts via the diff context menu.
      git-gui: Mark forgotten strings for translation.
      git-gui: Allow specifying an initial line for git gui blame.
      git-gui: Better positioning in Blame Parent Commit
      git-gui: Support passing blame to a parent commit.
      git-gui: Support starting gitk from Gui Blame
      git-gui: Teach git gui about file type changes

    * git://git.kernel.org/pub/scm/gitk/gitk:
      gitk: Add menu item for calling git gui blame
      gitk: Add option to specify the default commit on command line

git-gui/lib/blame.tcl

@@ -58,7 +58,7 @@ field tooltip_t         {} ; # Text widget in $tooltip_wm
 field tooltip_timer     {} ; # Current timer event for our tooltip
 field tooltip_commit    {} ; # Commit(s) in tooltip
 
-constructor new {i_commit i_path} {
+constructor new {i_commit i_path i_jump} {
 	global cursor_ptr
 	variable active_color
 	variable group_colors
@@ -259,6 +259,12 @@ constructor new {i_commit i_path} {
 	$w.ctxm add command \
 		-label [mc "Do Full Copy Detection"] \
 		-command [cb _fullcopyblame]
+	$w.ctxm add command \
+		-label [mc "Show History Context"] \
+		-command [cb _gitkcommit]
+	$w.ctxm add command \
+		-label [mc "Blame Parent Commit"] \
+		-command [cb _blameparent]
 
 	foreach i $w_columns {
 		for {set g 0} {$g < [llength $group_colors]} {incr g} {
@@ -332,7 +338,7 @@ constructor new {i_commit i_path} {
 	wm protocol $top WM_DELETE_WINDOW "destroy $top"
 	bind $top <Destroy> [cb _kill]
 
-	_load $this {}
+	_load $this $i_jump
 }
 
 method _kill {} {
@@ -787,19 +793,27 @@ method _load_commit {cur_w cur_d pos} {
 	set lno [lindex [split [$cur_w index $pos] .] 0]
 	set dat [lindex $line_data $lno]
 	if {$dat ne {}} {
-		lappend history [list \
-			$commit $path \
-			$highlight_column \
-			$highlight_line \
-			[lindex [$w_file xview] 0] \
-			[lindex [$w_file yview] 0] \
-			]
-		set commit [lindex $dat 0]
-		set path   [lindex $dat 1]
-		_load $this [list [lindex $dat 2]]
+		_load_new_commit $this  \
+			[lindex $dat 0] \
+			[lindex $dat 1] \
+			[list [lindex $dat 2]]
 	}
 }
 
+method _load_new_commit {new_commit new_path jump} {
+	lappend history [list \
+		$commit $path \
+		$highlight_column \
+		$highlight_line \
+		[lindex [$w_file xview] 0] \
+		[lindex [$w_file yview] 0] \
+		]
+
+	set commit $new_commit
+	set path   $new_path
+	_load $this $jump
+}
+
 method _showcommit {cur_w lno} {
 	global repo_config
 	variable active_color
@@ -905,10 +919,14 @@ method _showcommit {cur_w lno} {
 	}
 }
 
-method _copycommit {} {
+method _get_click_amov_info {} {
 	set pos @$::cursorX,$::cursorY
 	set lno [lindex [split [$::cursorW index $pos] .] 0]
-	set dat [lindex $amov_data $lno]
+	return [lindex $amov_data $lno]
+}
+
+method _copycommit {} {
+	set dat [_get_click_amov_info $this]
 	if {$dat ne {}} {
 		clipboard clear
 		clipboard append \
@@ -918,6 +936,124 @@ method _copycommit {} {
 	}
 }
 
+method _format_offset_date {base offset} {
+	set exval [expr {$base + $offset*24*60*60}]
+	return [clock format $exval -format {%Y-%m-%d}]
+}
+
+method _gitkcommit {} {
+	set dat [_get_click_amov_info $this]
+	if {$dat ne {}} {
+		set cmit [lindex $dat 0]
+		set radius [get_config gui.blamehistoryctx]
+		set cmdline [list --select-commit=$cmit]
+
+                if {$radius > 0} {
+			set author_time {}
+			set committer_time {}
+
+			catch {set author_time $header($cmit,author-time)}
+			catch {set committer_time $header($cmit,committer-time)}
+
+			if {$committer_time eq {}} {
+				set committer_time $author_time
+			}
+
+			set after_time [_format_offset_date $this $committer_time [expr {-$radius}]]
+			set before_time [_format_offset_date $this $committer_time $radius]
+
+			lappend cmdline --after=$after_time --before=$before_time
+		}
+
+		lappend cmdline $cmit
+
+		set base_rev "HEAD"
+		if {$commit ne {}} {
+			set base_rev $commit
+		}
+
+		if {$base_rev ne $cmit} {
+			lappend cmdline $base_rev
+		}
+
+		do_gitk $cmdline
+	}
+}
+
+method _blameparent {} {
+	set dat [_get_click_amov_info $this]
+	if {$dat ne {}} {
+		set cmit [lindex $dat 0]
+		set new_path [lindex $dat 1]
+
+		if {[catch {set cparent [git rev-parse --verify "$cmit^"]}]} {
+			error_popup [strcat [mc "Cannot find parent commit:"] "\n\n$err"]
+			return;
+		}
+
+		_kill $this
+
+		# Generate a diff between the commit and its parent,
+		# and use the hunks to update the line number.
+		# Request zero context to simplify calculations.
+		if {[catch {set fd [eval git_read diff-tree \
+				--unified=0 $cparent $cmit $new_path]} err]} {
+			$status stop [mc "Unable to display parent"]
+			error_popup [strcat [mc "Error loading diff:"] "\n\n$err"]
+			return
+		}
+
+		set r_orig_line [lindex $dat 2]
+
+		fconfigure $fd \
+			-blocking 0 \
+			-encoding binary \
+			-translation binary
+		fileevent $fd readable [cb _read_diff_load_commit \
+			$fd $cparent $new_path $r_orig_line]
+		set current_fd $fd
+	}
+}
+
+method _read_diff_load_commit {fd cparent new_path tline} {
+	if {$fd ne $current_fd} {
+		catch {close $fd}
+		return
+	}
+
+	while {[gets $fd line] >= 0} {
+		if {[regexp {^@@ -(\d+)(,(\d+))? \+(\d+)(,(\d+))? @@} $line line \
+			old_line osz old_size new_line nsz new_size]} {
+
+			if {$osz eq {}} { set old_size 1 }
+			if {$nsz eq {}} { set new_size 1 }
+
+			if {$new_line <= $tline} {
+				if {[expr {$new_line + $new_size}] > $tline} {
+					# Target line within the hunk
+					set line_shift [expr {
+						($new_size-$old_size)*($tline-$new_line)/$new_size
+						}]
+				} else {
+					set line_shift [expr {$new_size-$old_size}]
+				}
+
+				set r_orig_line [expr {$r_orig_line - $line_shift}]
+			}
+		}
+	}
+
+	if {[eof $fd]} {
+		close $fd;
+		set current_fd {}
+
+		_load_new_commit $this  \
+			$cparent        \
+			$new_path       \
+			[list $r_orig_line]
+	}
+} ifdeleted { catch {close $fd} }
+
 method _show_tooltip {cur_w pos} {
 	if {$tooltip_wm ne {}} {
 		_open_tooltip $this $cur_w

git-gui/lib/browser.tcl

@@ -151,7 +151,7 @@ method _enter {} {
 				append p [lindex $n 1]
 			}
 			append p $name
-			blame::new $browser_commit $p
+			blame::new $browser_commit $p {}
 		}
 		}
 	}

git-gui/lib/commit.tcl

@@ -149,7 +149,9 @@ The rescan will be automatically started now.
 		_? {continue}
 		A? -
 		D? -
+		T_ -
 		M? {set files_ready 1}
+		_U -
 		U? {
 			error_popup [mc "Unmerged files cannot be committed.
 
@@ -428,6 +430,7 @@ A rescan will be automatically started now.
 		__ -
 		A_ -
 		M_ -
+		T_ -
 		D_ {
 			unset file_states($path)
 			catch {unset selected_paths($path)}