As most of the git-gui interface is based upon "meta-widgets"
that need to carry around a good deal of state (e.g. console
windows, browser windows, blame viewer) we have a good deal
of messy code that tries to store this meta-widget state in
global arrays, where keys into the array are formed from a
union of a unique "object instance id" and the field name.
This is a simple class system for Tcl that allows us to
hide much of that mess by making Tcl do what it does best;
process strings to manipulate its own code during startup.
Each object instance is placed into its own namespace. The
namespace is created when the object instance is created and
the namespace is destroyed when the object instance is removed
from the system. Within that namespace we place variables for
each field within the class; these variables can themselves be
scalar values or full-blown Tcl arrays.
A simple class might be defined as:
class map {
field data
field size 0
constructor {} {
return $this
}
method set {name value} {
set data($name) $value
incr size
}
method size {} {
return $size
} ifdeleted { return 0 }
}
All fields must be declared before any constructors or methods. This
allows our class to generate a list of the fields so it can properly
alter the definition of the constructor and method bodies prior to
passing them off to Tcl for definition with proc. A field may optionally
be given a default/initial value. This can only be done for non-array
type fields.
Constructors are given full access to all fields of the class, so they
can initialize the data values. The default values of fields (if any)
are set before the constructor runs, and the implicit local variable
$this is initialized to the instance identifier.
Methods are given access to fields they actually use in their body.
Every method has an implicit "this" argument inserted as its first
parameter; callers of methods must be sure they supply this value.
Some basic optimization tricks are performed (but not much). We
try to only upvar (locally bind) fields that are accessed within a
method, but we err on the side of caution and may upvar more than
we need to. If a variable is accessed only once within a method
and that access is by $foo (read) we avoid the upvar and instead
use [set foo] to obtain the value. This is slightly faster as Tcl
does not need to lookup the variable twice.
We also offer some small syntatic sugar for interacting with Tk and
the fileevent callback system in Tcl. If a field (say "foo") is used
as "@foo" we insert instead the true global variable name of that
variable into the body of the constructor or method. This allows easy
binding to Tk textvariable options, e.g.:
label $w.title -textvariable @title
Proper namespace callbacks can also be setup with the special cb proc
that is defined in each namespace. [cb _foo a] will invoke the method
_foo in the current namespace, passing it $this as the first (implied)
parameter and a as the second parameter. This makes it very simple to
connect an object instance to a -command option for a Tk widget or to
a fileevent readable or writable for a file channel.
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
I found it useful to be able to use j/k (vi-like keys) to move
up and down the list of branches to merge and shift-j/k to do
the selection, much as shift-up/down (arrow keys) would alter
the selection.
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Since we support vi-like keys for scrolling in other UI contexts
we can easily do so here too. Tk's handy little `event generate'
makes this a lot easier than I thought it would be. We may want
to go back and fix some of the other vi-like bindings to redirect
to the arrow and pageup/pagedown keys, rather than running the
view changes directly.
I've bound 'v' to visualize, as this is a somewhat common thing
to want to do in the merge dialog. Control (or Command) Return
is also bound to start the merge, much as it is bound in the
main window to activate the commit.
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
When merging branches using our local merge feature it can be
handy to know the first few digits of the commit the ref points
at as well as the short description of the branch name.
Unfortunately I'm unable to use three listboxes in a row, as Tcl
freaks out and refuses to let me have a selection in more than
one of them at any given point in time. So instead we use a
fixed width font in the existing listbox and organize the data
into three columns. Not nearly as nice looking, but users can
continue to use the listbox's features.
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Johannes Sixt pointed out that git-gui was randomly selecting
which branch (or tag!) it will show in the merge dialog when
more than one ref points at the same commit. This can be a
problem for the user if they want to merge a branch, but the
ref that git-gui selected to display was actually a tag that
points at the commit at the tip of that branch. Since the
user is looking for the branch, and not the tag, its confusing
to not find it, and worse, merging the tag causes git-merge to
generate a different message than if the branch was selected.
While I am in here and am messing around I have changed the
for-each-ref usage to take advantage of its --tcl formatting,
and to fetch the subject line of the commit (or tag) we are
looking at. This way we could present the subject line in the
UI to the user, given them an even better chance to select
the correct branch.
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Like the console procs I have moved the code related to merge
support into their own namespace, so that they are isolated
from the rest of the world.
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Users who are used to vi and recent versions of gitk may want
to scroll the diff region using vi style keybindings. Since
these aren't bound to anything else and that widget does not
accept focus for data input, we can easily support that too.
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
To help modularize git-gui better I'm isolating the code and
variables required to handle our little console windows into
their own namespace. This way we can say console::new rather
than new_console, and the hidden internal procs to create the
window and read data from our filehandle are off in their own
private little land, where most users don't see them.
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
I'm finding it difficult to work with a 6,000+ line Tcl script
and not go insane while looking for a particular block of code.
Since most of the program is organized into different units of
functionality and not all users will need all units immediately
on startup we can improve things by splitting procs out into
multiple files and let auto_load handle things for us.
This should help not only to better organize the source, but
it may also improve startup times for some users as the Tcl
parser does not need to read as much script before it can show
the UI. In many cases the user can avoid reading at least half
of git-gui now.
Unfortunately we now need a library directory in our runtime
location. This is currently assumed to be $(sharedir)/git-gui/lib
and its expected that the Makefile invoker will setup some sort of
reasonable sharedir value for us, or let us assume its going to be
$(gitexecdir)/../share.
We now also require a tclsh (in TCL_PATH) to just run the Makefile,
as we use tclsh to generate the tclIndex for our lib directory. I'm
hoping this is not an unncessary burden on end-users who are building
from source.
I haven't really made any functionality changes here, this is just a
huge migration of code from one file to many smaller files. All of
the new changes are to setup the library path and install the library
files.
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
