git-tools/hooks/commit-msg


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

#!/bin/sh
#
# A hook to check syntax of a phpBB3 commit message, per:
# * <http://wiki.phpbb.com/display/DEV/Git>
# * <http://area51.phpbb.com/phpBB/viewtopic.php?p=209919#p209919>
#
# This is a commit-msg hook.
#
# To install this you can either copy or symlink it to
# $GIT_DIR/hooks, example:
#
# ln -s ../../git-tools/hooks/commit-msg \\
#   .git/hooks/commit-msg
#
# You can configure whether invalid commit messages abort commits:
#
# git config phpbb.hooks.commit-msg.fatal true	(abort)
# git config phpbb.hooks.commit-msg.fatal false (warn only, do not abort)
#
# The default is to warn only.
#
# Warning/error messages use color by default if the output is a terminal
# ("output" here is normally standard error when you run git commit).
# To force or disable the use of color:
#
# git config phpbb.hooks.commit-msg.color true	(force color output)
# git config phpbb.hooks.commit-msg.color false (disable color output)

config_ns="phpbb.hooks.commit-msg";

if [ "$(git config --bool $config_ns.fatal)" = "true" ]
then
	fatal=1;
	severity=Error;
else
	fatal=0;
	severity=Warning;
fi

debug_level=$(git config --int $config_ns.debug || echo 0);

# Error codes
ERR_LENGTH=1;
ERR_HEADER=2;
ERR_EMPTY=3;
ERR_DESCRIPTION=4;
ERR_FOOTER=5;
ERR_EOF=6;
ERR_UNKNOWN=42;

debug()
{
	local level;

	level=$1;
	shift;

	if [ $debug_level -ge $level ]
	then
		echo $@;
	fi
}

quit()
{
	if [ $1 -eq 0 ] || [ $1 -eq $ERR_UNKNOWN ]
	then
		# success
		exit 0;
	elif [ $fatal -eq 0 ]
	then
		# problems found but fatal is false
		complain 'Please run `git commit --amend` and fix the problems mentioned.' 1>&2
		exit 0;
	else
		complain "Aborting commit." 1>&2
		exit $1;
	fi
}

use_color()
{
	if [ -z "$use_color_cached" ]
	then
		case $(git config --bool $config_ns.color)
		in
		false)
			use_color_cached=1
			;;
		true)
			use_color_cached=0
			;;
		*)
			# tty detection in shell:
			# http://hwi.ath.cx/jsh/list/shext/isatty.sh.html
			tty 0>/dev/stdout >/dev/null 2>&1
			use_color_cached=$?
			;;
		esac
	fi
	# return value is the flag inverted -
	# if return value is 0, this means use color
	return $use_color_cached
}

complain()
{
	if use_color
	then
		# Careful: our argument may include arguments to echo like -n
		# ANSI color codes:
		# http://pueblo.sourceforge.net/doc/manual/ansi_color_codes.html
		printf "\033[31m\033[1m"
		if [ "$1" = "-n" ]
		then
			echo "$@"
			printf "\033[0m"
		else
			# This will print one trailing space.
			# Not sure how to avoid this at the moment.
			echo "$@" $(printf "\033[0m")
		fi
	else
		echo "$@"
	fi
}

# Check for empty commit message
if ! grep -qv '^#' "$1"
then
	# Commit message is empty (or contains only comments).
	# Let git handle this.
	# It will abort with a message like so:
	#
	# Aborting commit due to empty commit message.
	exit 0
fi

msg=$(grep -v '^#' "$1" |grep -nE '.{81,}')

if [ $? -eq 0 ]
then
	complain "The following lines are greater than 80 characters long:" >&2;
	complain >&2
	complain "$msg" >&2;

	quit $ERR_LENGTH;
fi

lines=$(wc -l "$1" | awk '{ print $1; }');
expecting=header;
in_description=0;
in_empty=0;
ticket=0;
branch_regex="[a-z]+[a-z0-9-]*[a-z0-9]+";
i=1;
tickets="";

while [ $i -le $lines ]
do
	# Grab the line we are studying
	line=$(head -n$i "$1" | tail -n1);

	debug 1 "==> [$i] $line (description: $in_description, empty: $in_empty)";

	err=$ERR_UNKNOWN;

	if [ -z "$expecting" ]
	then
		quit $err;
	fi

	if [ "${expecting#comment}" = "$expecting" ]
	then
		# Prefix comments to the expected tokens list
		expecting="comment $expecting";
	fi

	debug 2 "Expecting: $expecting";

	# Loop over each of the expected line formats
	for expect in $expecting
	do
		# Reset the error code each iteration
		err=$ERR_UNKNOWN;

		# Test for validity of each line format
		# This is done first so $? contains the result
		case $expect in
			"header")
				err=$ERR_HEADER;
				echo "$line" | grep -Eq "^\[(ticket/[0-9]+|feature/$branch_regex|task/$branch_regex)\] .+$"
				result=$?
				if ! echo "$line" | grep -Eq "^\[(ticket/[0-9]+|feature/$branch_regex|task/$branch_regex)\] [A-Z].+$"
				then
					# Don't be too strict.
					# Commits may be temporary, intended to be squashed later.
					# Just issue a warning here.
					complain "$severity: heading should be a sentence beginning with a capital letter." 1>&2
					complain "You entered:" 1>&2
					complain "$line" 1>&2
				fi
				# restore exit code
				(exit $result)
			;;
			"empty")
				err=$ERR_EMPTY;
				echo "$line" | grep -Eq "^$"
			;;
			"description")
				err=$ERR_DESCRIPTION;
				# Free flow text, the line length was constrained by the initial check
				echo "$line" | grep -Eq "^.+$";
			;;
			"footer")
				err=$ERR_FOOTER;
				# Each ticket is on its own line
				echo "$line" | grep -Eq "^PHPBB3-[0-9]+$";
			;;
			"eof")
				err=$ERR_EOF;
				# Should not end up here
				false
			;;
			"possibly-eof")
				# Allow empty and/or comment lines at the end
				! tail -n +"$i" "$1" |grep -qvE '^($|#)'
			;;
			"comment")
				echo "$line" | grep -Eq "^#";
			;;
			*)
				complain "Unrecognised token $expect" >&2;
				quit $err;
			;;
		esac

		# Preserve the result of the line check
		result=$?;

		debug 2 "$expect - '$line' - $result";

		if [ $result -eq 0 ]
		then
			# Break out the loop on success
			# otherwise roll on round and keep looking for a match
			break;
		fi
	done

	if [ $result -eq 0 ]
	then
		# Have we switched out of description mode?
		if [ $in_description -eq 1 ] && [ "$expect" != "description" ] && [ "$expect" != "empty" ] && [ "$expect" != "comment" ]
		then
			# Yes, okay we need to backtrace one line and reanalyse
			in_description=0;
			i=$(( $i - $in_empty ));

			# Reset the empty counter
			in_empty=0;
			continue;
		fi

		# Successful match, but on which line format
		case $expect in
			"header")
				expecting="empty";

				echo "$line" | grep -Eq "^\[ticket/[0-9]+\]$" && (
					ticket=$(echo "$line" | sed 's,\[ticket/\([0-9]*\)\].*,\1,');
				)
			;;
			"empty")
				# Description might have empty lines as spacing
				expecting="footer description";
				in_empty=$(($in_empty + 1));

				if [ $in_description -eq 1 ]
				then
					expecting="$expecting empty";
				fi
			;;
			"description")
				expecting="description empty";
				in_description=1;
			;;
			"footer")
				expecting="footer possibly-eof";
				if [ "$tickets" = "" ]
				then
					tickets="$line";
				else
					tickets="$tickets $line";
				fi
			;;
			"comment")
				# Comments should expect the same thing again
			;;
			"possibly-eof")
				expecting="eof";
			;;
			*)
				complain "Unrecognised token $expect" >&2;
				quit 254;
			;;
		esac

		if [ "$expect" != "empty" ]
		then
			in_empty=0;
		fi

		debug 3 "Now expecting: $expecting";
	else
		# None of the expected line formats matched
		# Guess we'll call it a day here then
		complain "Syntax error on line $i:" >&2;
		complain ">> $line" >&2;
		complain -n "Expecting: " >&2;
		complain "$expecting" | sed 's/ /, /g' >&2;
		quit $err;
	fi

	i=$(( $i + 1 ));
done

# If EOF is expected exit cleanly
echo "$expecting" | grep -q "eof" || (
	# Unexpected EOF, error
	complain "Unexpected EOF encountered" >&2;
	quit $ERR_EOF;
) && (
	# Do post scan checks
	if [ ! -z "$tickets" ]
	then
		# Check for duplicate tickets
		dupes=$(echo "$tickets" | sed 's/ /\n/g' | sort | uniq -d);

		if [ ! -z "$dupes" ]
		then
			complain "The following tickets are repeated:" >&2;
			complain "$dupes" | sed 's/ /\n/g;s/^/* /g' >&2;
			quit $ERR_FOOTER;
		fi
	fi
	# Check the branch ticket is mentioned, doesn't make sense otherwise
	if [ $ticket -gt 0 ]
	then
		echo "$tickets" | grep -Eq "\bPHPBB3-$ticket\b" || (
			complain "Ticket ID [$ticket] of branch missing from list of tickets:" >&2;
			complain "$tickets" | sed 's/ /\n/g;s/^/* /g' >&2;
			quit $ERR_FOOTER;
		) || exit $?;
	fi
	# Got here okay exit to reality
	exit 0;
);
exit $?;