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 00a994be120edaa1024733cb94e3f1fe4e494039..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
+                       }
+                       }
                }
        }