git-gui: Simplify error case for unsupported merge types

[git.git] / lib / checkout_op.tcl

diff --git a/lib/checkout_op.tcl b/lib/checkout_op.tcl
index 5d02daac6f910e465cee271971ff799c0cc38b97..554c107032458f3b9585b58d7920924acf0ecb69 100644 (file)
--- a/lib/checkout_op.tcl
+++ b/lib/checkout_op.tcl
@@ -12,6 +12,7 @@ field new_ref    ; # ref we are updating/creating
 
 field parent_w      .; # window that started us
 field merge_type none; # type of merge to apply to existing branch
+field merge_base   {}; # merge base if we have another ref involved
 field fetch_spec   {}; # refetch tracking branch if used?
 field checkout      1; # actually checkout the branch?
 field create        0; # create the branch if it doesn't exist?
@@ -180,29 +181,24 @@ method _update_ref {} {
                # No merge would be required, don't compute anything.
                #
        } else {
-               set mrb {}
-               catch {set mrb [git merge-base $new $cur]}
-               switch -- $merge_type {
-               ff {
-                       if {$mrb eq $new} {
-                               # The current branch is actually newer.
-                               #
-                               set new $cur
-                       } elseif {$mrb eq $cur} {
-                               # The current branch is older.
-                               #
-                               set reflog_msg "merge $new_expr: Fast-forward"
-                       } else {
-                               _error $this "Branch '$newbranch' already exists.\n\nIt cannot fast-forward to $new_expr.\nA merge is required."
-                               return 0
+               catch {set merge_base [git merge-base $new $cur]}
+               if {$merge_base eq $cur} {
+                       # The current branch is older.
+                       #
+                       set reflog_msg "merge $new_expr: Fast-forward"
+               } else {
+                       switch -- $merge_type {
+                       ff {
+                               if {$merge_base eq $new} {
+                                       # The current branch is actually newer.
+                                       #
+                                       set new $cur
+                               } else {
+                                       _error $this "Branch '$newbranch' already exists.\n\nIt cannot fast-forward to $new_expr.\nA merge is required."
+                                       return 0
+                               }
                        }
-               }
-               reset {
-                       if {$mrb eq $cur} {
-                               # The current branch is older.
-                               #
-                               set reflog_msg "merge $new_expr: Fast-forward"
-                       } else {
+                       reset {
                                # The current branch will lose things.
                                #
                                if {[_confirm_reset $this $cur]} {
@@ -211,11 +207,11 @@ method _update_ref {} {
                                        return 0
                                }
                        }
-               }
-               default {
-                       _error $this "Only 'ff' and 'reset' merge is currently supported."
-                       return 0
-               }
+                       default {
+                               _error $this "Merge strategy '$merge_type' not supported."
+                               return 0
+                       }
+                       }
                }
        }
 
@@ -274,12 +270,12 @@ The rescan will be automatically started now.
                _readtree $this
        } else {
                ui_status {Refreshing file status...}
-               set cmd [list git update-index]
-               lappend cmd -q
-               lappend cmd --unmerged
-               lappend cmd --ignore-missing
-               lappend cmd --refresh
-               set fd [open "| $cmd" r]
+               set fd [git_read update-index \
+                       -q \
+                       --unmerged \
+                       --ignore-missing \
+                       --refresh \
+                       ]
                fconfigure $fd -blocking 0 -translation binary
                fileevent $fd readable [cb _refresh_wait $fd]
        }
@@ -315,23 +311,14 @@ method _readtree {} {
                "Updating working directory to '[_name $this]'..." \
                {files checked out}
 
-       set cmd [list git read-tree]
-       lappend cmd -m
-       lappend cmd -u
-       lappend cmd -v
-       lappend cmd --exclude-per-directory=.gitignore
-       lappend cmd $HEAD
-       lappend cmd $new_hash
-
-       if {[catch {
-                       set fd [open "| $cmd 2>@1" r]
-               } err]} {
-               # Older versions of Tcl 8.4 don't have this 2>@1 IO
-               # redirect operator.  Fallback to |& cat for those.
-               #
-               set fd [open "| $cmd |& cat" r]
-       }
-
+       set fd [git_read --stderr read-tree \
+               -m \
+               -u \
+               -v \
+               --exclude-per-directory=.gitignore \
+               $HEAD \
+               $new_hash \
+               ]
        fconfigure $fd -blocking 0 -translation binary
        fileevent $fd readable [cb _readtree_wait $fd]
 }
@@ -524,7 +511,7 @@ method _confirm_reset {cur} {
        pack $w.buttons.cancel -side right -padx 5
        pack $w.buttons -side bottom -fill x -pady 10 -padx 10
 
-       set fd [open "| git rev-list --pretty=oneline $cur ^$new_hash" r]
+       set fd [git_read rev-list --pretty=oneline $cur ^$new_hash]
        while {[gets $fd line] > 0} {
                set abbr [string range $line 0 7]
                set subj [string range $line 41 end]