For all you darcs lovers: git-hunk-commit

For all you darcs lovers: git-hunk-commit

[Johannes Schindelin]

[-- Attachment #1: Type: TEXT/PLAIN, Size: 926 bytes --]

Hi,

I was inspired by Han-Wen. This script allows you to commit selected hunks 
from the current modifications.

It has two modes: darcs mode (--darcs) and normal mode (without 
arguments).

In darcs mode, all hunks are presented one by one, and you are asked if 
you want to commit this or not. If you make a mistake: ^C and back to 
start. I do not really know darcs, so this might not be how it works -- I 
did not find any good documentation how a "darcs record" looks like.

Normal mode shows you the list of modified files, and lets you choose one. 
Then it shows you how many hunks there are, and lets you pick one for 
inspection, after which you are asked if you want it or not.

Normal mode is chattier, but if you know which (of those thousands) hunk 
you want to commit, it is faster. Besides, it was easier to debug.

Note that this script uses no temporary files, but rather bash array 
variables.

Ciao,
Dscho

[-- Attachment #2: Type: TEXT/PLAIN, Size: 5604 bytes --]

#!/bin/bash

# Copyright (C) 2006 Johannes E. Schindelin
# Distributed under the same license as git.

# Use this command to commit just a few hunks of the current output
# of "git diff". For your security, it only works when the index matches
# HEAD.

# ensure that this is a git repository
. git-sh-setup

# the index must match the HEAD
if [ -n "$(git diff --index --name-only HEAD)" ]; then
	echo "The staging area (AKA index) is already dirty."
	exit 1
fi

# read the names of all modified files into the array "modified"

declare -a modified
filenr=1
while read -d $'\0' file; do
	modified[$filenr]="$file"
	filenr=$(($filenr+1))
done < <(git ls-files --modified -z)

if [ ${#modified[*]} = 0 ]; then
	echo "No modified files."
	exit 1
fi

declare -a hunks

# interactively show the hunks of a file and ask if they should be committed.
# 1st parameter is the index into the modified file list.
# 2nd parameter should be "true" for darcs mode, empty otherwise.
#	Darcs mode means that all hunks are presented one after another.
#	Normal mode means user can specify hunks interactively.

select_hunks () {
	local index=$1
	local darcs_mode=$2
	local filename=${modified[$index]}
	local -a diff
	local -a hunk_start
	local current_hunks=${hunks[$index]}
	local lineno
	local hunkno
	local action
	local i
	local active

	lineno=1
	hunkno=0
	while read line; do
		diff[$lineno]="$line"
		case "$line" in
		@@*)
			hunk_start[$hunkno]=$lineno
			hunkno=$(($hunkno+1))
			;;
		esac
		lineno=$(($lineno+1))
	done < <(git diff "$filename")

	hunk_start[$hunkno]=$lineno

	action=""
	while [ "$action" != commit -a "$action" != abort ]; do
		case "$darcs_mode" in
		'')
			echo
			echo "Current hunks: ($current_hunks) of $hunkno hunks"
			echo "To show (and decide on) a hunk type in the number."
			echo "To commit the current hunks, say 'commit', else 'abort'."
			echo
			echo -n "Your choice? "
			read action
			;;
		[1-9]*)
			darcs_mode=$(($darcs_mode+1))
			if [ $darcs_mode -gt $hunkno ]; then
				action=commit
			else
				action=$darcs_mode
			fi
			;;
		*)
			darcs_mode=1
			action=1
			;;
		esac
		case "$action" in
		c) action=commit;;
		q|a) action=abort;;
		commit|abort) ;;
		[1-9]*)
			echo
			for ((i=${hunk_start[$(($action-1))]}; i<${hunk_start[$action]}; i++)); do
				if [ -n "$darcs_mode" -a $i = ${hunk_start[0]} ]; then
					echo "File: $filename"
				fi
				echo ${diff[$i]}
			done | less -FS
			active=$(echo $current_hunks,$action | tr , '\n' | sort | uniq -u | tr '\n' , | sed -e "s/^,//" -e "s/,$//")
			if [ ${#active} -lt ${#current_hunks} ]; then
				i=yes
			else
				i=no
			fi
			echo
			while [ -n "$action" -a "$action" != yes -a "$action" != no -a -n "$action" ]; do
				echo -n "Commit this hunk (default is $i)? "
				read action
				case "$action" in
				y) action=yes;;
				n) action=no;;
				esac
			done
			if [ -n "$action" -a $i != "$action" ]; then
				current_hunks=$active
			fi
			;;
		*) echo "Unknown command: $action";;
		esac
	done

	if [ "$action" = commit ]; then
		hunks[$index]=$current_hunks
	fi
}

# Apply the hunks saved in the array hunks for the specified file.
# This means that the diff is rewritten to skip the unwanted hunks.

apply_hunks () {
	local index=$1
	local filename=${modified[$index]}
	local -a current_hunks
	local lineno
	local lineno2
	local linediff
	local hunkno
	local i
	local active

	i=0
	while read hunkno; do
		current_hunks[$i]=$hunkno
		i=$(($i+1))
	done < <(echo ${hunks[$index]} | tr , '\n')

	linediff=0
	hunkno=0
	i=0
	active=true
	while read line
	do
		case "$line" in
		@@*)
			hunkno=$(($hunkno+1))
			if [ $hunkno = "${current_hunks[$i]}" ]; then
				active=true
				i=$(($i+1))
				if [ $linediff -ne 0 ]; then
					lineno=$(echo "$line" | sed "s/^.*+\([0-9]*\)[, ].*$/\1/")
					lineno2=$(($lineno+$linediff))
					line="$(echo "$line" | sed "s/+$lineno/+$lineno2/")"
				fi
			else
				active=
				lineno=$(echo "$line" | sed -n "s/^.*-[0-9]*,\([0-9]*\) .*$/\1/p")
				if [ -z "$lineno" ]; then
					lineno=1
				fi
				lineno2=$(echo "$line" | sed -n "s/^.*+[0-9]*,\([0-9]*\) .*$/\1/p")
				if [ -z "$lineno2" ]; then
					lineno2=1
				fi
				linediff=$(($linediff+$lineno-$lineno2))
			fi
			;;
		esac
		if [ -n "$active" ]; then
			echo "$line"
		fi
	done < <(git diff "$filename")
}

darcs_mode=
case "$1" in
--darcs) darcs_mode=true;;
esac

IFS=''
action=
i=
while [ "$action" != commit -a "$action" != abort ]; do
	case "$darcs_mode" in
	'')
		echo
		for ((i=1; i<$filenr; i++)); do
			echo -n "$i ${modified[$i]}"
			if [ -n "${hunks[$i]}" ]; then
				echo " (${hunks[$i]})"
			else
				echo
			fi
		done | less -FS
		echo
		echo "To put one or more hunks of a file into the staging area (AKA"
		echo "index), type in the number of the file."
		echo "To commit, say 'commit', to abort, say 'abort'."
		echo
		echo -n "Your choice? "
		read action
		;;
	true)
		if [ -z "$i" ]; then
			i=1
		else
			i=$(($i+1))
		fi
		if [ $i -ge $filenr ]; then
			action=commit
		else
			action=$i
		fi
		;;
	esac
	case "$action" in
	c) action=commit;;
	q|a) action=abort;;
	commit|abort) ;;
	[0-9]*) select_hunks "$action" "$darcs_mode";;
	*) echo "Unknown command." ;;
	esac
done

if [ "$action" = commit ]; then
	for ((i=1; i<$filenr; i++)); do
		if [ -n "${hunks[$i]}" ]; then
			apply_hunks $i
		fi
	done | tee a123 | git apply --cached
	git commit
fi

Re: For all you darcs lovers: git-hunk-commit

[Han-Wen Nienhuys]

Johannes Schindelin escreveu:
> I was inspired by Han-Wen. This script allows you to commit selected hunks 

Wow!

> In darcs mode, all hunks are presented one by one, and you are asked if 
> you want to commit this or not. If you make a mistake: ^C and back to 
> start. I do not really know darcs, so this might not be how it works -- I 
> did not find any good documentation how a "darcs record" looks like.


This is the interactive interface for commits in Darcs. It uses the
same interface for pushing and pulling, where I mostly use y/n/a/d but
sometimes the other letters too.


****
Shall I record this change? (1/?)  [ynWsfqadjkc], or ? for help: ?
How to use record...
y: record this patch
n: don't record it
w: wait and decide later, defaulting to no

s: don't record the rest of the changes to this file
f: record the rest of the changes to this file

d: record selected patches, skipping all the remaining patches
a: record all the remaining patches
q: cancel record

j: skip to next patch
k: back up to previous patch
c: calculate number of patches
h or ?: show this help

<Space>: accept the current default (which is capitalized)
****



If you want to get a feel for it, grab darcs and run

  darcs init
  echo hello > hello
  darcs add
  darcs record
  

For a really neat implementation of per-hunk commits, try running
darcsum in Emacs


> done < <(git ls-files --modified -z)

> 	done < <(git diff "$filename")

> 	done < <(echo ${hunks[$index]} | tr , '\n')

am I running the wrong bash? it barf on this. Don't you mean $(echo ... )

Frankly, I am amazed that people write things in bash at all--I vowed never
to write bash again a couple of years ago.  If you start doing arrays and
counting, wouldn't a more high-level language be suitable?

-- 
 Han-Wen Nienhuys - hanwen@xs4all.nl - http://www.xs4all.nl/~hanwen

Re: For all you darcs lovers: git-hunk-commit

[Johannes Schindelin]

Hi,

On Wed, 6 Dec 2006, Han-Wen Nienhuys wrote:

> This is the interactive interface for commits in Darcs. It uses the
> same interface for pushing and pulling, where I mostly use y/n/a/d but
> sometimes the other letters too.
> 
> 
> ****
> Shall I record this change? (1/?)  [ynWsfqadjkc], or ? for help: ?
> How to use record...
> y: record this patch
> n: don't record it
> w: wait and decide later, defaulting to no
> 
> s: don't record the rest of the changes to this file
> f: record the rest of the changes to this file
> 
> d: record selected patches, skipping all the remaining patches
> a: record all the remaining patches
> q: cancel record
> 
> j: skip to next patch
> k: back up to previous patch
> c: calculate number of patches
> h or ?: show this help
> 
> <Space>: accept the current default (which is capitalized)
> ****

All but "y" and "n" are unsupported in hunk-commit.bash... Do you use all 
of these?

> If you want to get a feel for it, grab darcs and run

I already grabbed darcs a long time ago. And run, I did.

> > done < <(git ls-files --modified -z)
> 
> > 	done < <(git diff "$filename")
> 
> > 	done < <(echo ${hunks[$index]} | tr , '\n')
> 
> am I running the wrong bash? it barf on this. Don't you mean $(echo ... )

I hoped that I did not use a too new bash. Unfortunately, I seem to have 
been wrong. These constructs redirect the output of the command as input 
to the while loop, because

	bla | while ...; do blub; done

opens a subshell, so that all changes done in "blub" are lost as soon as 
the while loop is finished.

> Frankly, I am amazed that people write things in bash at all--I vowed 
> never to write bash again a couple of years ago.  If you start doing 
> arrays and counting, wouldn't a more high-level language be suitable?

Me, being one of the loudest proponents of C builtins on this list, I 
agree fully.

But in this case, bash was faster to script and debug, and unless people 
speak up, saying "I want that feature badly!", I do not plan to do 
anything with it.

Ciao,
Dscho

Re: For all you darcs lovers: git-hunk-commit

[Matthias Kestenholz]

Hi,

On Wed, 2006-12-06 at 01:36 +0100, Johannes Schindelin wrote:
> But in this case, bash was faster to script and debug, and unless people 
> speak up, saying "I want that feature badly!", I do not plan to do 
> anything with it.

This feature is _very_ handy and I think it would be great if this
became part of the default git distribution.

Thanks for writing this tool!

Matthias

Re: For all you darcs lovers: git-hunk-commit

[Johannes Schindelin]

Hi,

On Fri, 8 Dec 2006, Matthias Kestenholz wrote:

> On Wed, 2006-12-06 at 01:36 +0100, Johannes Schindelin wrote:
> > But in this case, bash was faster to script and debug, and unless people 
> > speak up, saying "I want that feature badly!", I do not plan to do 
> > anything with it.
> 
> This feature is _very_ handy and I think it would be great if this
> became part of the default git distribution.

Note that it requires a relatively new bash version ATM, because of the 
"while read line; do ...; done < <(cmd)" construct. I have another version 
which substitutes a temporary file for that, but I keep thinking that a 
graphical tool, such as git-gui, would be more appropriate. BTW I just did 
it in bash, because I wanted to learn about these famous bash arrays.

Ciao,
Dscho