gitk: Improve handling of -- and ambiguous arguments

This makes gitk more consistent with git rev-list and git log in its
handling of arguments that could be either a revision or a filename;
now gitk displays an error message and quits, rather than treating it
as a revision and getting an error in the underlying git log.  Now
gitk always passes "--" to git log even if no filenames are being
specified.

It also makes gitk display errors in invoking git log in a window
rather than on stderr, and makes gitk stop looking for a -d flag
when it sees a "--" argument.

Signed-off-by: Paul Mackerras <paulus@samba.org>

diff --git a/gitk b/gitk
index 468cf32228997f597f1fa1f5cb516da0e8512fa5..b9219c2c70c64ab70b29ce3f0416037af080f0fe 100755 (executable)
--- a/gitk
+++ b/gitk
@@ -87,19 +87,15 @@ proc start_rev_list {view} {
 
     set startmsecs [clock clicks -milliseconds]
     set commitidx($view) 0
-    set args $viewargs($view)
-    if {$viewfiles($view) ne {}} {
-       set args [concat $args "--" $viewfiles($view)]
-    }
     set order "--topo-order"
     if {$datemode} {
        set order "--date-order"
     }
     if {[catch {
-       set fd [open [concat | git log -z --pretty=raw $order \
-                         --parents --boundary $args] r]
+       set fd [open [concat | git log -z --pretty=raw $order --parents \
+                        --boundary $viewargs($view) "--" $viewfiles($view)] r]
     } err]} {
-       puts stderr "Error executing git rev-list: $err"
+       error_popup "Error executing git rev-list: $err"
        exit 1
     }
     set commfd($view) $fd
@@ -7471,35 +7467,48 @@ catch {source ~/.gitk}
 
 font create optionfont -family sans-serif -size -12
 
+# check that we can find a .git directory somewhere...
+set gitdir [gitdir]
+if {![file isdirectory $gitdir]} {
+    show_error {} . "Cannot find the git directory \"$gitdir\"."
+    exit 1
+}
+
 set revtreeargs {}
+set cmdline_files {}
+set i 0
 foreach arg $argv {
     switch -regexp -- $arg {
        "^$" { }
        "^-d" { set datemode 1 }
+       "--" {
+           set cmdline_files [lrange $argv [expr {$i + 1}] end]
+           break
+       }
        default {
            lappend revtreeargs $arg
        }
     }
+    incr i
 }
 
-# check that we can find a .git directory somewhere...
-set gitdir [gitdir]
-if {![file isdirectory $gitdir]} {
-    show_error {} . "Cannot find the git directory \"$gitdir\"."
-    exit 1
-}
-
-set cmdline_files {}
-set i [lsearch -exact $revtreeargs "--"]
-if {$i >= 0} {
-    set cmdline_files [lrange $revtreeargs [expr {$i + 1}] end]
-    set revtreeargs [lrange $revtreeargs 0 [expr {$i - 1}]]
-} elseif {$revtreeargs ne {}} {
+if {$i >= [llength $argv] && $revtreeargs ne {}} {
+    # no -- on command line, but some arguments (other than -d)
     if {[catch {
        set f [eval exec git rev-parse --no-revs --no-flags $revtreeargs]
        set cmdline_files [split $f "\n"]
        set n [llength $cmdline_files]
        set revtreeargs [lrange $revtreeargs 0 end-$n]
+       # Unfortunately git rev-parse doesn't produce an error when
+       # something is both a revision and a filename.  To be consistent
+       # with git log and git rev-list, check revtreeargs for filenames.
+       foreach arg $revtreeargs {
+           if {[file exists $arg]} {
+               show_error {} . "Ambiguous argument '$arg': both revision\
+                                and filename"
+               exit 1
+           }
+       }
     } err]} {
        # unfortunately we get both stdout and stderr in $err,
        # so look for "fatal:".