about summary refs log tree commit diff
path: root/git-mergetool--lib.sh
blob: 204a5acd66f5444412f0088b8df6cb0ae2fd6b41 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
# git-mergetool--lib is a shell library for common merge tool functions

: ${MERGE_TOOLS_DIR=$(git --exec-path)/mergetools}

IFS='
'

mode_ok () {
	if diff_mode
	then
		can_diff
	elif merge_mode
	then
		can_merge
	else
		false
	fi
}

is_available () {
	merge_tool_path=$(translate_merge_tool_path "$1") &&
	type "$merge_tool_path" >/dev/null 2>&1
}

list_config_tools () {
	section=$1
	line_prefix=${2:-}

	git config --get-regexp $section'\..*\.cmd' |
	while read -r key value
	do
		toolname=${key#$section.}
		toolname=${toolname%.cmd}

		printf "%s%s\n" "$line_prefix" "$toolname"
	done
}

show_tool_names () {
	condition=${1:-true} per_line_prefix=${2:-} preamble=${3:-}
	not_found_msg=${4:-}
	extra_content=${5:-}

	shown_any=
	( cd "$MERGE_TOOLS_DIR" && ls ) | {
		while read toolname
		do
			if setup_tool "$toolname" 2>/dev/null &&
				(eval "$condition" "$toolname")
			then
				if test -n "$preamble"
				then
					printf "%s\n" "$preamble"
					preamble=
				fi
				shown_any=yes
				printf "%s%s\n" "$per_line_prefix" "$toolname"
			fi
		done

		if test -n "$extra_content"
		then
			if test -n "$preamble"
			then
				# Note: no '\n' here since we don't want a
				# blank line if there is no initial content.
				printf "%s" "$preamble"
				preamble=
			fi
			shown_any=yes
			printf "\n%s\n" "$extra_content"
		fi

		if test -n "$preamble" && test -n "$not_found_msg"
		then
			printf "%s\n" "$not_found_msg"
		fi

		test -n "$shown_any"
	}
}

diff_mode () {
	test "$TOOL_MODE" = diff
}

merge_mode () {
	test "$TOOL_MODE" = merge
}

gui_mode () {
	test "$GIT_MERGETOOL_GUI" = true
}

translate_merge_tool_path () {
	echo "$1"
}

check_unchanged () {
	if test "$MERGED" -nt "$BACKUP"
	then
		return 0
	else
		while true
		do
			echo "$MERGED seems unchanged."
			printf "Was the merge successful [y/n]? "
			read answer || return 1
			case "$answer" in
			y*|Y*) return 0 ;;
			n*|N*) return 1 ;;
			esac
		done
	fi
}

valid_tool () {
	setup_tool "$1" && return 0
	cmd=$(get_merge_tool_cmd "$1")
	test -n "$cmd"
}

setup_user_tool () {
	merge_tool_cmd=$(get_merge_tool_cmd "$tool")
	test -n "$merge_tool_cmd" || return 1

	diff_cmd () {
		( eval $merge_tool_cmd )
	}

	merge_cmd () {
		( eval $merge_tool_cmd )
	}
}

setup_tool () {
	tool="$1"

	# Fallback definitions, to be overridden by tools.
	can_merge () {
		return 0
	}

	can_diff () {
		return 0
	}

	diff_cmd () {
		return 1
	}

	merge_cmd () {
		return 1
	}

	translate_merge_tool_path () {
		echo "$1"
	}

	# Most tools' exit codes cannot be trusted, so By default we ignore
	# their exit code and check the merged file's modification time in
	# check_unchanged() to determine whether or not the merge was
	# successful.  The return value from run_merge_cmd, by default, is
	# determined by check_unchanged().
	#
	# When a tool's exit code can be trusted then the return value from
	# run_merge_cmd is simply the tool's exit code, and check_unchanged()
	# is not called.
	#
	# The return value of exit_code_trustable() tells us whether or not we
	# can trust the tool's exit code.
	#
	# User-defined and built-in tools default to false.
	# Built-in tools advertise that their exit code is trustable by
	# redefining exit_code_trustable() to true.

	exit_code_trustable () {
		false
	}


	if ! test -f "$MERGE_TOOLS_DIR/$tool"
	then
		setup_user_tool
		return $?
	fi

	# Load the redefined functions
	. "$MERGE_TOOLS_DIR/$tool"
	# Now let the user override the default command for the tool.  If
	# they have not done so then this will return 1 which we ignore.
	setup_user_tool

	if merge_mode && ! can_merge
	then
		echo "error: '$tool' can not be used to resolve merges" >&2
		return 1
	elif diff_mode && ! can_diff
	then
		echo "error: '$tool' can only be used to resolve merges" >&2
		return 1
	fi
	return 0
}

get_merge_tool_cmd () {
	merge_tool="$1"
	if diff_mode
	then
		git config "difftool.$merge_tool.cmd" ||
		git config "mergetool.$merge_tool.cmd"
	else
		git config "mergetool.$merge_tool.cmd"
	fi
}

trust_exit_code () {
	if git config --bool "mergetool.$1.trustExitCode"
	then
		:; # OK
	elif exit_code_trustable
	then
		echo true
	else
		echo false
	fi
}


# Entry point for running tools
run_merge_tool () {
	# If GIT_PREFIX is empty then we cannot use it in tools
	# that expect to be able to chdir() to its value.
	GIT_PREFIX=${GIT_PREFIX:-.}
	export GIT_PREFIX

	merge_tool_path=$(get_merge_tool_path "$1") || exit
	base_present="$2"

	# Bring tool-specific functions into scope
	setup_tool "$1" || return 1

	if merge_mode
	then
		run_merge_cmd "$1"
	else
		run_diff_cmd "$1"
	fi
}

# Run a either a configured or built-in diff tool
run_diff_cmd () {
	diff_cmd "$1"
}

# Run a either a configured or built-in merge tool
run_merge_cmd () {
	mergetool_trust_exit_code=$(trust_exit_code "$1")
	if test "$mergetool_trust_exit_code" = "true"
	then
		merge_cmd "$1"
	else
		touch "$BACKUP"
		merge_cmd "$1"
		check_unchanged
	fi
}

list_merge_tool_candidates () {
	if merge_mode
	then
		tools="tortoisemerge"
	else
		tools="kompare"
	fi
	if test -n "$DISPLAY"
	then
		if test -n "$GNOME_DESKTOP_SESSION_ID"
		then
			tools="meld opendiff kdiff3 tkdiff xxdiff $tools"
		else
			tools="opendiff kdiff3 tkdiff xxdiff meld $tools"
		fi
		tools="$tools gvimdiff diffuse diffmerge ecmerge"
		tools="$tools p4merge araxis bc codecompare"
		tools="$tools smerge"
	fi
	case "${VISUAL:-$EDITOR}" in
	*vim*)
		tools="$tools vimdiff emerge"
		;;
	*)
		tools="$tools emerge vimdiff"
		;;
	esac
}

show_tool_help () {
	tool_opt="'git ${TOOL_MODE}tool --tool=<tool>'"

	tab='	'
	LF='
'
	any_shown=no

	cmd_name=${TOOL_MODE}tool
	config_tools=$({
		diff_mode && list_config_tools difftool "$tab$tab"
		list_config_tools mergetool "$tab$tab"
	} | sort)
	extra_content=
	if test -n "$config_tools"
	then
		extra_content="${tab}user-defined:${LF}$config_tools"
	fi

	show_tool_names 'mode_ok && is_available' "$tab$tab" \
		"$tool_opt may be set to one of the following:" \
		"No suitable tool for 'git $cmd_name --tool=<tool>' found." \
		"$extra_content" &&
		any_shown=yes

	show_tool_names 'mode_ok && ! is_available' "$tab$tab" \
		"${LF}The following tools are valid, but not currently available:" &&
		any_shown=yes

	if test "$any_shown" = yes
	then
		echo
		echo "Some of the tools listed above only work in a windowed"
		echo "environment. If run in a terminal-only session, they will fail."
	fi
	exit 0
}

guess_merge_tool () {
	list_merge_tool_candidates
	cat >&2 <<-EOF

	This message is displayed because '$TOOL_MODE.tool' is not configured.
	See 'git ${TOOL_MODE}tool --tool-help' or 'git help config' for more details.
	'git ${TOOL_MODE}tool' will now attempt to use one of the following tools:
	$tools
	EOF

	# Loop over each candidate and stop when a valid merge tool is found.
	IFS=' '
	for tool in $tools
	do
		is_available "$tool" && echo "$tool" && return 0
	done

	echo >&2 "No known ${TOOL_MODE} tool is available."
	return 1
}

get_configured_merge_tool () {
	keys=
	if diff_mode
	then
		if gui_mode
		then
			keys="diff.guitool merge.guitool diff.tool merge.tool"
		else
			keys="diff.tool merge.tool"
		fi
	else
		if gui_mode
		then
			keys="merge.guitool merge.tool"
		else
			keys="merge.tool"
		fi
	fi

	merge_tool=$(
		IFS=' '
		for key in $keys
		do
			selected=$(git config $key)
			if test -n "$selected"
			then
				echo "$selected"
				return
			fi
		done)

	if test -n "$merge_tool" && ! valid_tool "$merge_tool"
	then
		echo >&2 "git config option $TOOL_MODE.${gui_prefix}tool set to unknown tool: $merge_tool"
		echo >&2 "Resetting to default..."
		return 1
	fi
	echo "$merge_tool"
}

get_merge_tool_path () {
	# A merge tool has been set, so verify that it's valid.
	merge_tool="$1"
	if ! valid_tool "$merge_tool"
	then
		echo >&2 "Unknown merge tool $merge_tool"
		exit 1
	fi
	if diff_mode
	then
		merge_tool_path=$(git config difftool."$merge_tool".path ||
				  git config mergetool."$merge_tool".path)
	else
		merge_tool_path=$(git config mergetool."$merge_tool".path)
	fi
	if test -z "$merge_tool_path"
	then
		merge_tool_path=$(translate_merge_tool_path "$merge_tool")
	fi
	if test -z "$(get_merge_tool_cmd "$merge_tool")" &&
		! type "$merge_tool_path" >/dev/null 2>&1
	then
		echo >&2 "The $TOOL_MODE tool $merge_tool is not available as"\
			 "'$merge_tool_path'"
		exit 1
	fi
	echo "$merge_tool_path"
}

get_merge_tool () {
	is_guessed=false
	# Check if a merge tool has been configured
	merge_tool=$(get_configured_merge_tool)
	# Try to guess an appropriate merge tool if no tool has been set.
	if test -z "$merge_tool"
	then
		merge_tool=$(guess_merge_tool) || exit
		is_guessed=true
	fi
	echo "$merge_tool"
	test "$is_guessed" = false
}

mergetool_find_win32_cmd () {
	executable=$1
	sub_directory=$2

	# Use $executable if it exists in $PATH
	if type -p "$executable" >/dev/null 2>&1
	then
		printf '%s' "$executable"
		return
	fi

	# Look for executable in the typical locations
	for directory in $(env | grep -Ei '^PROGRAM(FILES(\(X86\))?|W6432)=' |
		cut -d '=' -f 2- | sort -u)
	do
		if test -n "$directory" && test -x "$directory/$sub_directory/$executable"
		then
			printf '%s' "$directory/$sub_directory/$executable"
			return
		fi
	done

	printf '%s' "$executable"
}