unofficial mirror of emacs-devel@gnu.org 
 help / color / mirror / code / Atom feed
blob 694d4529b97333f48f9deb60dc2d6a1d2f5caadb 58929 bytes (raw)
name: lisp/vc/smerge-mode.el 	 # note: path name is non-authoritative(*)

   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
 464
 465
 466
 467
 468
 469
 470
 471
 472
 473
 474
 475
 476
 477
 478
 479
 480
 481
 482
 483
 484
 485
 486
 487
 488
 489
 490
 491
 492
 493
 494
 495
 496
 497
 498
 499
 500
 501
 502
 503
 504
 505
 506
 507
 508
 509
 510
 511
 512
 513
 514
 515
 516
 517
 518
 519
 520
 521
 522
 523
 524
 525
 526
 527
 528
 529
 530
 531
 532
 533
 534
 535
 536
 537
 538
 539
 540
 541
 542
 543
 544
 545
 546
 547
 548
 549
 550
 551
 552
 553
 554
 555
 556
 557
 558
 559
 560
 561
 562
 563
 564
 565
 566
 567
 568
 569
 570
 571
 572
 573
 574
 575
 576
 577
 578
 579
 580
 581
 582
 583
 584
 585
 586
 587
 588
 589
 590
 591
 592
 593
 594
 595
 596
 597
 598
 599
 600
 601
 602
 603
 604
 605
 606
 607
 608
 609
 610
 611
 612
 613
 614
 615
 616
 617
 618
 619
 620
 621
 622
 623
 624
 625
 626
 627
 628
 629
 630
 631
 632
 633
 634
 635
 636
 637
 638
 639
 640
 641
 642
 643
 644
 645
 646
 647
 648
 649
 650
 651
 652
 653
 654
 655
 656
 657
 658
 659
 660
 661
 662
 663
 664
 665
 666
 667
 668
 669
 670
 671
 672
 673
 674
 675
 676
 677
 678
 679
 680
 681
 682
 683
 684
 685
 686
 687
 688
 689
 690
 691
 692
 693
 694
 695
 696
 697
 698
 699
 700
 701
 702
 703
 704
 705
 706
 707
 708
 709
 710
 711
 712
 713
 714
 715
 716
 717
 718
 719
 720
 721
 722
 723
 724
 725
 726
 727
 728
 729
 730
 731
 732
 733
 734
 735
 736
 737
 738
 739
 740
 741
 742
 743
 744
 745
 746
 747
 748
 749
 750
 751
 752
 753
 754
 755
 756
 757
 758
 759
 760
 761
 762
 763
 764
 765
 766
 767
 768
 769
 770
 771
 772
 773
 774
 775
 776
 777
 778
 779
 780
 781
 782
 783
 784
 785
 786
 787
 788
 789
 790
 791
 792
 793
 794
 795
 796
 797
 798
 799
 800
 801
 802
 803
 804
 805
 806
 807
 808
 809
 810
 811
 812
 813
 814
 815
 816
 817
 818
 819
 820
 821
 822
 823
 824
 825
 826
 827
 828
 829
 830
 831
 832
 833
 834
 835
 836
 837
 838
 839
 840
 841
 842
 843
 844
 845
 846
 847
 848
 849
 850
 851
 852
 853
 854
 855
 856
 857
 858
 859
 860
 861
 862
 863
 864
 865
 866
 867
 868
 869
 870
 871
 872
 873
 874
 875
 876
 877
 878
 879
 880
 881
 882
 883
 884
 885
 886
 887
 888
 889
 890
 891
 892
 893
 894
 895
 896
 897
 898
 899
 900
 901
 902
 903
 904
 905
 906
 907
 908
 909
 910
 911
 912
 913
 914
 915
 916
 917
 918
 919
 920
 921
 922
 923
 924
 925
 926
 927
 928
 929
 930
 931
 932
 933
 934
 935
 936
 937
 938
 939
 940
 941
 942
 943
 944
 945
 946
 947
 948
 949
 950
 951
 952
 953
 954
 955
 956
 957
 958
 959
 960
 961
 962
 963
 964
 965
 966
 967
 968
 969
 970
 971
 972
 973
 974
 975
 976
 977
 978
 979
 980
 981
 982
 983
 984
 985
 986
 987
 988
 989
 990
 991
 992
 993
 994
 995
 996
 997
 998
 999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
 
;;; smerge-mode.el --- Minor mode to resolve diff3 conflicts -*- lexical-binding: t -*-

;; Copyright (C) 1999-2021 Free Software Foundation, Inc.

;; Author: Stefan Monnier <monnier@iro.umontreal.ca>
;; Keywords: vc, tools, revision control, merge, diff3, cvs, conflict

;; This file is part of GNU Emacs.

;; GNU Emacs is free software: you can redistribute it and/or modify
;; it under the terms of the GNU General Public License as published by
;; the Free Software Foundation, either version 3 of the License, or
;; (at your option) any later version.

;; GNU Emacs is distributed in the hope that it will be useful,
;; but WITHOUT ANY WARRANTY; without even the implied warranty of
;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
;; GNU General Public License for more details.

;; You should have received a copy of the GNU General Public License
;; along with GNU Emacs.  If not, see <https://www.gnu.org/licenses/>.

;;; Commentary:

;; Provides a lightweight alternative to emerge/ediff.
;; To use it, simply add to your .emacs the following lines:
;;
;;   (autoload 'smerge-mode "smerge-mode" nil t)
;;
;; you can even have it turned on automatically with the following
;; piece of code in your .emacs:
;;
;;   (defun sm-try-smerge ()
;;     (save-excursion
;;   	 (goto-char (point-min))
;;   	 (when (re-search-forward "^<<<<<<< " nil t)
;;   	   (smerge-mode 1))))
;;   (add-hook 'find-file-hook 'sm-try-smerge t)

;;; Todo:

;; - if requested, ask the user whether he wants to call ediff right away

;;; Code:

(eval-when-compile (require 'cl-lib))
(require 'diff)				;For diff-check-labels.
(require 'diff-mode)                    ;For diff-refine.
(require 'newcomment)

;;; The real definition comes later.
(defvar smerge-mode)

(defgroup smerge ()
  "Minor mode to highlight and resolve diff3 conflicts."
  :group 'tools
  :prefix "smerge-")

(defcustom smerge-diff-buffer-name "*vc-diff*"
  "Buffer name to use for displaying diffs."
  :type '(choice
	  (const "*vc-diff*")
	  (const "*cvs-diff*")
	  (const "*smerge-diff*")
	  string))

(defcustom smerge-diff-switches
  (append '("-d" "-b")
	  (if (listp diff-switches) diff-switches (list diff-switches)))
  "A list of strings specifying switches to be passed to diff.
Used in `smerge-diff-base-upper' and related functions."
  :type '(repeat string))

(defcustom smerge-auto-leave t
  "Non-nil means to leave `smerge-mode' when the last conflict is resolved."
  :type 'boolean)

(defface smerge-upper
  '((((class color) (min-colors 88) (background light))
     :background "#ffdddd" :extend t)
    (((class color) (min-colors 88) (background dark))
     :background "#553333" :extend t)
    (((class color))
     :foreground "red" :extend))
  "Face for the `upper' version of a conflict.")
(define-obsolete-face-alias 'smerge-mine 'smerge-upper "26.1")
(defvar smerge-upper-face 'smerge-upper)

(defface smerge-lower
  '((((class color) (min-colors 88) (background light))
     :background "#ddffdd" :extend t)
    (((class color) (min-colors 88) (background dark))
     :background "#335533" :extend t)
    (((class color))
     :foreground "green" :extend))
  "Face for the `lower' version of a conflict.")
(define-obsolete-face-alias 'smerge-other 'smerge-lower "26.1")
(defvar smerge-lower-face 'smerge-lower)

(defface smerge-base
  '((((class color) (min-colors 88) (background light))
     :background "#ffffaa" :extend t)
    (((class color) (min-colors 88) (background dark))
     :background "#888833" :extend t)
    (((class color))
     :foreground "yellow" :extend t))
  "Face for the base code.")
(defvar smerge-base-face 'smerge-base)

(defface smerge-markers
  '((((background light))
     (:background "grey85" :extend t))
    (((background dark))
     (:background "grey30" :extend t)))
  "Face for the conflict markers.")
(defvar smerge-markers-face 'smerge-markers)

(defface smerge-refined-changed
  '((t nil))
  "Face used for char-based changes shown by `smerge-refine'.")
(define-obsolete-face-alias 'smerge-refined-change 'smerge-refined-changed "24.5")

(defface smerge-refined-removed
  '((default
     :inherit smerge-refined-change)
    (((class color) (min-colors 88) (background light))
     :background "#ffbbbb")
    (((class color) (min-colors 88) (background dark))
     :background "#aa2222")
    (t :inverse-video t))
  "Face used for removed characters shown by `smerge-refine'."
  :version "24.3")

(defface smerge-refined-added
  '((default
     :inherit smerge-refined-change)
    (((class color) (min-colors 88) (background light))
     :background "#aaffaa")
    (((class color) (min-colors 88) (background dark))
     :background "#22aa22")
    (t :inverse-video t))
  "Face used for added characters shown by `smerge-refine'."
  :version "24.3")

(easy-mmode-defmap smerge-basic-map
  `(("n" . smerge-next)
    ("p" . smerge-prev)
    ("r" . smerge-resolve)
    ("a" . smerge-keep-all)
    ("b" . smerge-keep-base)
    ("o" . smerge-keep-lower)           ; for the obsolete keep-other
    ("l" . smerge-keep-lower)
    ("m" . smerge-keep-upper)           ; for the obsolete keep-mine
    ("u" . smerge-keep-upper)
    ("E" . smerge-ediff)
    ("C" . smerge-combine-with-next)
    ("R" . smerge-refine)
    ("\C-m" . smerge-keep-current)
    ("=" . ,(make-sparse-keymap "Diff"))
    ("=<" "base-upper" . smerge-diff-base-upper)
    ("=>" "base-lower" . smerge-diff-base-lower)
    ("==" "upper-lower" . smerge-diff-upper-lower))
  "The base keymap for `smerge-mode'.")

(defcustom smerge-command-prefix "\C-c^"
  "Prefix for `smerge-mode' commands."
  :type '(choice (const :tag "ESC"   "\e")
		 (const :tag "C-c ^" "\C-c^" )
		 (const :tag "none"  "")
		 string))

(easy-mmode-defmap smerge-mode-map
  `((,smerge-command-prefix . ,smerge-basic-map))
  "Keymap for `smerge-mode'.")

(defvar-local smerge-check-cache nil)
(defun smerge-check (n)
  (condition-case nil
      (let ((state (cons (point) (buffer-modified-tick))))
	(unless (equal (cdr smerge-check-cache) state)
	  (smerge-match-conflict)
	  (setq smerge-check-cache (cons (match-data) state)))
	(nth (* 2 n) (car smerge-check-cache)))
    (error nil)))

(easy-menu-define smerge-mode-menu smerge-mode-map
  "Menu for `smerge-mode'."
  '("SMerge"
    ["Next" smerge-next :help "Go to next conflict"]
    ["Previous" smerge-prev :help "Go to previous conflict"]
    "--"
    ["Keep All" smerge-keep-all :help "Keep all three versions"
     :active (smerge-check 1)]
    ["Keep Current" smerge-keep-current :help "Use current (at point) version"
     :active (and (smerge-check 1) (> (smerge-get-current) 0))]
    "--"
    ["Revert to Base" smerge-keep-base :help "Revert to base version"
     :active (smerge-check 2)]
    ["Keep Upper" smerge-keep-upper :help "Keep `upper' version"
     :active (smerge-check 1)]
    ["Keep Lower" smerge-keep-lower :help "Keep `lower' version"
     :active (smerge-check 3)]
    "--"
    ["Diff Base/Upper" smerge-diff-base-upper
     :help "Diff `base' and `upper' for current conflict"
     :active (smerge-check 2)]
    ["Diff Base/Lower" smerge-diff-base-lower
     :help "Diff `base' and `lower' for current conflict"
     :active (smerge-check 2)]
    ["Diff Upper/Lower" smerge-diff-upper-lower
     :help "Diff `upper' and `lower' for current conflict"
     :active (smerge-check 1)]
    "--"
    ["Invoke Ediff" smerge-ediff
     :help "Use Ediff to resolve the conflicts"
     :active (smerge-check 1)]
    ["Auto Resolve" smerge-resolve
     :help "Try auto-resolution heuristics"
     :active (smerge-check 1)]
    ["Combine" smerge-combine-with-next
     :help "Combine current conflict with next"
     :active (smerge-check 1)]
    ))

(easy-menu-define smerge-context-menu nil
  "Context menu for upper area in `smerge-mode'."
  '(nil
    ["Keep Current" smerge-keep-current :help "Use current (at point) version"]
    ["Kill Current" smerge-kill-current :help "Remove current (at point) version"]
    ["Keep All" smerge-keep-all :help "Keep all three versions"]
    "---"
    ["More..." (popup-menu smerge-mode-menu) :help "Show full SMerge mode menu"]
    ))

(defconst smerge-font-lock-keywords
  '((smerge-find-conflict
     (1 smerge-upper-face prepend t)
     (2 smerge-base-face prepend t)
     (3 smerge-lower-face prepend t)
     ;; FIXME: `keep' doesn't work right with syntactic fontification.
     (0 smerge-markers-face keep)
     (4 nil t t)
     (5 nil t t)))
  "Font lock patterns for `smerge-mode'.")

(defconst smerge-begin-re "^<<<<<<< \\(.*\\)\n")
(defconst smerge-end-re "^>>>>>>> \\(.*\\)\n")
(defconst smerge-base-re "^||||||| \\(.*\\)\n")
(defconst smerge-lower-re "^=======\n")

(defvar smerge-conflict-style nil
  "Keep track of which style of conflict is in use.
Can be nil if the style is undecided, or else:
- `diff3-E'
- `diff3-A'")

;; Compiler pacifiers
(defvar font-lock-mode)
(defvar font-lock-keywords)

;;;;
;;;; Actual code
;;;;

;; Define smerge-next and smerge-prev
(easy-mmode-define-navigation smerge smerge-begin-re "conflict" nil nil
  (if diff-refine
      (condition-case nil (smerge-refine) (error nil))))

(defconst smerge-match-names ["conflict" "upper" "base" "lower"])

(defun smerge-ensure-match (n)
  (unless (match-end n)
    (error "No `%s'" (aref smerge-match-names n))))

(defun smerge-auto-leave ()
  (when (and smerge-auto-leave
	     (save-excursion (goto-char (point-min))
			     (not (re-search-forward smerge-begin-re nil t))))
    (when (and (listp buffer-undo-list) smerge-mode)
      (push (list 'apply 'smerge-mode 1) buffer-undo-list))
    (smerge-mode -1)))


(defun smerge-keep-all ()
  "Concatenate all versions."
  (interactive)
  (smerge-match-conflict)
  (let ((mb2 (or (match-beginning 2) (point-max)))
	(me2 (or (match-end 2) (point-min))))
    (delete-region (match-end 3) (match-end 0))
    (delete-region (max me2 (match-end 1)) (match-beginning 3))
    (if (and (match-end 2) (/= (match-end 1) (match-end 3)))
	(delete-region (match-end 1) (match-beginning 2)))
    (delete-region (match-beginning 0) (min (match-beginning 1) mb2))
    (smerge-auto-leave)))

(defun smerge-keep-n (n)
  (smerge-remove-props (match-beginning 0) (match-end 0))
  ;; We used to use replace-match, but that did not preserve markers so well.
  (delete-region (match-end n) (match-end 0))
  (delete-region (match-beginning 0) (match-beginning n)))

(defun smerge-combine-with-next ()
  "Combine the current conflict with the next one."
  ;; `smerge-auto-combine' relies on the finish position (at the beginning
  ;; of the closing marker).
  (interactive)
  (smerge-match-conflict)
  (let ((ends nil))
    (dolist (i '(3 2 1 0))
      (push (if (match-end i) (copy-marker (match-end i) t)) ends))
    (setq ends (apply 'vector ends))
    (goto-char (aref ends 0))
    (if (not (re-search-forward smerge-begin-re nil t))
	(error "No next conflict")
      (smerge-match-conflict)
      (let ((match-data (mapcar (lambda (m) (if m (copy-marker m)))
				(match-data))))
	;; First copy the in-between text in each alternative.
	(dolist (i '(1 2 3))
	  (when (aref ends i)
	    (goto-char (aref ends i))
	    (insert-buffer-substring (current-buffer)
				     (aref ends 0) (car match-data))))
	(delete-region (aref ends 0) (car match-data))
	;; Then move the second conflict's alternatives into the first.
	(dolist (i '(1 2 3))
	  (set-match-data match-data)
	  (when (and (aref ends i) (match-end i))
	    (goto-char (aref ends i))
	    (insert-buffer-substring (current-buffer)
				     (match-beginning i) (match-end i))))
	(delete-region (car match-data) (cadr match-data))
	;; Free the markers.
	(dolist (m match-data) (if m (move-marker m nil)))
	(mapc (lambda (m) (if m (move-marker m nil))) ends)))))

(defvar smerge-auto-combine-max-separation 2
  "Max number of lines between conflicts that should be combined.")

(defun smerge-auto-combine ()
  "Automatically combine conflicts that are near each other."
  (interactive)
  (save-excursion
    (goto-char (point-min))
    (while (smerge-find-conflict)
      ;; 2 is 1 (default) + 1 (the begin markers).
      (while (save-excursion
               (smerge-find-conflict
                (line-beginning-position
                 (+ 2 smerge-auto-combine-max-separation))))
        (forward-line -1)               ;Go back inside the conflict.
        (smerge-combine-with-next)
        (forward-line 1)                ;Move past the end of the conflict.
        ))))

(defvar smerge-resolve-function
  (lambda () (user-error "Don't know how to resolve"))
  "Mode-specific merge function.
The function is called with zero or one argument (non-nil if the resolution
function should only apply safe heuristics) and with the match data set
according to `smerge-match-conflict'.")

(defvar smerge-text-properties
  '(help-echo "merge conflict: mouse-3 shows a menu"
              ;; mouse-face highlight
              keymap (keymap (down-mouse-3 . smerge-popup-context-menu))))

(defun smerge-remove-props (beg end)
  (remove-overlays beg end 'smerge 'refine)
  (remove-overlays beg end 'smerge 'conflict)
  ;; Now that we use overlays rather than text-properties, this function
  ;; does not cause refontification any more.  It can be seen very clearly
  ;; in buffers where jit-lock-contextually is not t, in which case deleting
  ;; the "<<<<<<< foobar" leading line leaves the rest of the conflict
  ;; highlighted as if it were still a valid conflict.  Note that in many
  ;; important cases (such as the previous example) we're actually called
  ;; during font-locking so inhibit-modification-hooks is non-nil, so we
  ;; can't just modify the buffer and expect font-lock to be triggered as in:
  ;; (put-text-property beg end 'smerge-force-highlighting nil)
  (with-silent-modifications
    (remove-text-properties beg end '(fontified nil))))

(defun smerge-popup-context-menu (event)
  "Pop up the Smerge mode context menu under mouse."
  (interactive "e")
  (if (and smerge-mode
	   (save-excursion (posn-set-point (event-end event)) (smerge-check 1)))
      (progn
	(posn-set-point (event-end event))
	(smerge-match-conflict)
	(let ((i (smerge-get-current))
	      o)
	  (if (<= i 0)
	      ;; Out of range
	      (popup-menu smerge-mode-menu)
	    ;; Install overlay.
	    (setq o (make-overlay (match-beginning i) (match-end i)))
	    (unwind-protect
		(progn
		  (overlay-put o 'face 'highlight)
		  (sit-for 0)		;Display the new highlighting.
		  (popup-menu smerge-context-menu))
	      ;; Delete overlay.
	      (delete-overlay o)))))
    ;; There's no conflict at point, the text-props are just obsolete.
    (save-excursion
      (let ((beg (re-search-backward smerge-end-re nil t))
	    (end (re-search-forward smerge-begin-re nil t)))
	(smerge-remove-props (or beg (point-min)) (or end (point-max)))
	(push event unread-command-events)))))

(defun smerge-apply-resolution-patch (buf m0b m0e m3b m3e &optional m2b)
  "Replace the conflict with a bunch of subconflicts.
BUF contains a plain diff between match-1 and match-3."
  (let ((line 1)
        (textbuf (current-buffer))
        (name1 (progn (goto-char m0b)
                      (buffer-substring (+ (point) 8) (line-end-position))))
        (name2 (when m2b (goto-char m2b) (forward-line -1)
                     (buffer-substring (+ (point) 8) (line-end-position))))
        (name3 (progn (goto-char m0e) (forward-line -1)
                      (buffer-substring (+ (point) 8) (line-end-position)))))
    (smerge-remove-props m0b m0e)
    (delete-region m3e m0e)
    (delete-region m0b m3b)
    (setq m3b m0b)
    (setq m3e (- m3e (- m3b m0b)))
    (goto-char m3b)
    (with-current-buffer buf
      (goto-char (point-min))
      (while (not (eobp))
        (if (not (looking-at "\\([0-9]+\\)\\(?:,\\([0-9]+\\)\\)?\\([acd]\\)\\([0-9]+\\)\\(?:,\\([0-9]+\\)\\)?$"))
            (error "Unexpected patch hunk header: %s"
                   (buffer-substring (point) (line-end-position)))
          (let* ((op (char-after (match-beginning 3)))
                 (startline (+ (string-to-number (match-string 1))
                               ;; No clue why this is the way it is, but line
                               ;; numbers seem to be off-by-one for `a' ops.
                               (if (eq op ?a) 1 0)))
                 (endline (if (eq op ?a) startline
                            (1+ (if (match-end 2)
                                    (string-to-number (match-string 2))
                                  startline))))
                 (lines (- endline startline))
                 (otherlines (cond
                              ((eq op ?d) nil)
                              ((null (match-end 5)) 1)
                              (t (- (string-to-number (match-string 5))
                                    (string-to-number (match-string 4)) -1))))
                 othertext)
            (forward-line 1)                             ;Skip header.
            (forward-line lines)                         ;Skip deleted text.
            (if (eq op ?c) (forward-line 1))             ;Skip separator.
            (setq othertext
                  (if (null otherlines) ""
                    (let ((pos (point)))
                      (dotimes (_i otherlines) (delete-char 2) (forward-line 1))
                      (buffer-substring pos (point)))))
            (with-current-buffer textbuf
              (forward-line (- startline line))
              (insert "<<<<<<< " name1 "\n" othertext
                      (if name2 (concat "||||||| " name2 "\n") "")
                      "=======\n")
              (forward-line lines)
              (insert ">>>>>>> " name3 "\n")
              (setq line endline))))))))

(defconst smerge-resolve--normalize-re "[\n\t][ \t\n]*\\| [ \t\n]+")

(defun smerge-resolve--extract-comment (beg end)
  "Extract the text within the comments that span BEG..END."
  (save-excursion
    (let ((comments ())
          combeg)
      (goto-char beg)
      (while (and (< (point) end)
                  (setq combeg (comment-search-forward end t)))
        (let ((beg (point)))
          (goto-char combeg)
          (comment-forward 1)
          (save-excursion
            (comment-enter-backward)
            (push " " comments)
            (push (buffer-substring-no-properties beg (point)) comments))))
      (push " " comments)
      (with-temp-buffer
        (apply #'insert (nreverse comments))
        (goto-char (point-min))
        (while (re-search-forward smerge-resolve--normalize-re
                                  nil t)
          (replace-match " "))
        (buffer-string)))))

(defun smerge-resolve--normalize (beg end)
  (replace-regexp-in-string
   smerge-resolve--normalize-re " "
   (concat " " (buffer-substring-no-properties beg end) " ")))

(defun smerge-resolve (&optional safe)
  "Resolve the conflict at point intelligently.
This relies on mode-specific knowledge and thus only works in some
major modes.  Uses `smerge-resolve-function' to do the actual work."
  (interactive)
  (smerge-match-conflict)
  (smerge-remove-props (match-beginning 0) (match-end 0))
  (let ((md (match-data))
	(m0b (match-beginning 0))
	(m1b (match-beginning 1))
	(m2b (match-beginning 2))
	(m3b (match-beginning 3))
	(m0e (match-end 0))
	(m1e (match-end 1))
	(m2e (match-end 2))
	(m3e (match-end 3))
	(buf (generate-new-buffer " *smerge*"))
        m b o
        choice)
    (unwind-protect
	(progn
          (cond
           ;; Trivial diff3 -A non-conflicts.
           ((and (eq (match-end 1) (match-end 3))
                 (eq (match-beginning 1) (match-beginning 3)))
            (smerge-keep-n 3))
           ;; Mode-specific conflict resolution.
           ((condition-case nil
                (atomic-change-group
                  (if safe
                      (funcall smerge-resolve-function safe)
                    (funcall smerge-resolve-function))
                  t)
              (error nil))
            ;; Nothing to do: the resolution function has done it already.
            nil)
           ;; Non-conflict.
	   ((and (eq m1e m3e) (eq m1b m3b))
	    (set-match-data md) (smerge-keep-n 3))
           ;; Refine a 2-way conflict using "diff -b".
           ;; In case of a 3-way conflict with an empty base
           ;; (i.e. 2 conflicting additions), we do the same, presuming
           ;; that the 2 additions should be somehow merged rather
           ;; than concatenated.
	   ((let ((lines (count-lines m3b m3e)))
              (setq m (make-temp-file "smm"))
              (write-region m1b m1e m nil 'silent)
              (setq o (make-temp-file "smo"))
              (write-region m3b m3e o nil 'silent)
              (not (or (eq m1b m1e) (eq m3b m3e)
                       (and (not (zerop (call-process diff-command
                                                      nil buf nil "-b" o m)))
                            ;; TODO: We don't know how to do the refinement
                            ;; if there's a non-empty ancestor and m1 and m3
                            ;; aren't just plain equal.
                            m2b (not (eq m2b m2e)))
                       (with-current-buffer buf
                         (goto-char (point-min))
                         ;; Make sure there's some refinement.
                         (looking-at
                          (concat "1," (number-to-string lines) "c"))))))
            (smerge-apply-resolution-patch buf m0b m0e m3b m3e m2b))
	   ;; "Mere whitespace changes" conflicts.
           ((when m2e
              (setq b (make-temp-file "smb"))
              (write-region m2b m2e b nil 'silent)
              (with-current-buffer buf (erase-buffer))
              ;; Only minor whitespace changes made locally.
              ;; BEWARE: pass "-c" 'cause the output is reused in the next test.
              (zerop (call-process diff-command nil buf nil "-bc" b m)))
            (set-match-data md)
	    (smerge-keep-n 3))
	   ;; Try "diff -b BASE UPPER | patch LOWER".
	   ((when (and (not safe) m2e b
                       ;; If the BASE is empty, this would just concatenate
                       ;; the two, which is rarely right.
                       (not (eq m2b m2e)))
              ;; BEWARE: we're using here the patch of the previous test.
	      (with-current-buffer buf
		(zerop (call-process-region
			(point-min) (point-max) "patch" t nil nil
			"-r" null-device "--no-backup-if-mismatch"
			"-fl" o))))
	    (save-restriction
	      (narrow-to-region m0b m0e)
              (smerge-remove-props m0b m0e)
	      (insert-file-contents o nil nil nil t)))
	   ;; Try "diff -b BASE LOWER | patch UPPER".
	   ((when (and (not safe) m2e b
                       ;; If the BASE is empty, this would just concatenate
                       ;; the two, which is rarely right.
                       (not (eq m2b m2e)))
	      (write-region m3b m3e o nil 'silent)
	      (call-process diff-command nil buf nil "-bc" b o)
	      (with-current-buffer buf
		(zerop (call-process-region
			(point-min) (point-max) "patch" t nil nil
			"-r" null-device "--no-backup-if-mismatch"
			"-fl" m))))
	    (save-restriction
	      (narrow-to-region m0b m0e)
              (smerge-remove-props m0b m0e)
	      (insert-file-contents m nil nil nil t)))
           ;; If the conflict is only made of comments, and one of the two
           ;; changes is only rearranging spaces (e.g. reflowing text) while
           ;; the other is a real change, drop the space-rearrangement.
           ((and m2e
                 (comment-only-p m1b m1e)
                 (comment-only-p m2b m2e)
                 (comment-only-p m3b m3e)
                 (let ((t1 (smerge-resolve--extract-comment m1b m1e))
                       (t2 (smerge-resolve--extract-comment m2b m2e))
                       (t3 (smerge-resolve--extract-comment m3b m3e)))
                   (cond
                    ((and (equal t1 t2) (not (equal t2 t3)))
                     (setq choice 3))
                    ((and (not (equal t1 t2)) (equal t2 t3))
                     (setq choice 1)))))
            (set-match-data md)
	    (smerge-keep-n choice))
           ;; Idem, when the conflict is contained within a single comment.
           ((save-excursion
              (and m2e
                   (nth 4 (syntax-ppss m0b))
                   ;; If there's a conflict earlier in the file,
                   ;; syntax-ppss is not reliable.
                   (not (re-search-backward smerge-begin-re nil t))
                   (progn (goto-char (nth 8 (syntax-ppss m0b)))
                          (forward-comment 1)
                          (> (point) m0e))
                   (let ((t1 (smerge-resolve--normalize m1b m1e))
                         (t2 (smerge-resolve--normalize m2b m2e))
                         (t3 (smerge-resolve--normalize m3b m3e)))
                     (cond
                    ((and (equal t1 t2) (not (equal t2 t3)))
                     (setq choice 3))
                    ((and (not (equal t1 t2)) (equal t2 t3))
                     (setq choice 1))))))
            (set-match-data md)
	    (smerge-keep-n choice))
           (t
            (user-error "Don't know how to resolve"))))
      (if (buffer-name buf) (kill-buffer buf))
      (if m (delete-file m))
      (if b (delete-file b))
      (if o (delete-file o))))
  (smerge-auto-leave))

(defun smerge-resolve-all ()
  "Perform automatic resolution on all conflicts."
  (interactive)
  (save-excursion
    (goto-char (point-min))
    (while (re-search-forward smerge-begin-re nil t)
      (condition-case nil
          (progn
            (smerge-match-conflict)
            (smerge-resolve 'safe))
        (error nil)))))

(defun smerge-batch-resolve ()
  ;; command-line-args-left is what is left of the command line.
  (if (not noninteractive)
      (error "`smerge-batch-resolve' is to be used only with -batch"))
  (while command-line-args-left
    (let ((file (pop command-line-args-left)))
      (if (string-match "\\.rej\\'" file)
          ;; .rej files should never contain diff3 markers, on the other hand,
          ;; in Arch, .rej files are sometimes used to indicate that the
          ;; main file has diff3 markers.  So you can pass **/*.rej and
          ;; it will DTRT.
          (setq file (substring file 0 (match-beginning 0))))
      (message "Resolving conflicts in %s..." file)
      (when (file-readable-p file)
        (with-current-buffer (find-file-noselect file)
          (smerge-resolve-all)
          (save-buffer)
          (kill-buffer (current-buffer)))))))

(defun smerge-keep-base ()
  "Revert to the base version."
  (interactive)
  (smerge-match-conflict)
  (smerge-ensure-match 2)
  (smerge-keep-n 2)
  (smerge-auto-leave))

(defun smerge-keep-lower ()
  "Keep the \"lower\" version of a merge conflict.
In a conflict that looks like:
  <<<<<<<
  UUU
  =======
  LLL
  >>>>>>>
this keeps \"LLL\"."
  (interactive)
  (smerge-match-conflict)
  ;;(smerge-ensure-match 3)
  (smerge-keep-n 3)
  (smerge-auto-leave))

(define-obsolete-function-alias 'smerge-keep-other 'smerge-keep-lower "26.1")

(defun smerge-keep-upper ()
  "Keep the \"upper\" version of a merge conflict.
In a conflict that looks like:
  <<<<<<<
  UUU
  =======
  LLL
  >>>>>>>
this keeps \"UUU\"."
  (interactive)
  (smerge-match-conflict)
  ;;(smerge-ensure-match 1)
  (smerge-keep-n 1)
  (smerge-auto-leave))

(define-obsolete-function-alias 'smerge-keep-mine 'smerge-keep-upper "26.1")

(defun smerge-get-current ()
  (let ((i 3))
    (while (or (not (match-end i))
	       (< (point) (match-beginning i))
	       (> (point) (match-end i)))
      (cl-decf i))
    i))

(defun smerge-keep-current ()
  "Use the current (under the cursor) version."
  (interactive)
  (smerge-match-conflict)
  (let ((i (smerge-get-current)))
    (if (<= i 0) (error "Not inside a version")
      (smerge-keep-n i)
      (smerge-auto-leave))))

(defun smerge-kill-current ()
  "Remove the current (under the cursor) version."
  (interactive)
  (smerge-match-conflict)
  (let ((i (smerge-get-current)))
    (if (<= i 0) (error "Not inside a version")
      (let ((left nil))
	(dolist (n '(3 2 1))
	  (if (and (match-end n) (/= (match-end n) (match-end i)))
	      (push n left)))
	(if (and (cdr left)
		 (/= (match-end (car left)) (match-end (cadr left))))
	    (ding)			;We don't know how to do that.
	  (smerge-keep-n (car left))
	  (smerge-auto-leave))))))

(defun smerge-diff-base-upper ()
  "Diff `base' and `upper' version in current conflict region."
  (interactive)
  (smerge-diff 2 1))

(define-obsolete-function-alias 'smerge-diff-base-mine
  'smerge-diff-base-upper "26.1")

(defun smerge-diff-base-lower ()
  "Diff `base' and `lower' version in current conflict region."
  (interactive)
  (smerge-diff 2 3))

(define-obsolete-function-alias 'smerge-diff-base-other
  'smerge-diff-base-lower "26.1")

(defun smerge-diff-upper-lower ()
  "Diff `upper' and `lower' version in current conflict region."
  (interactive)
  (smerge-diff 1 3))

(define-obsolete-function-alias 'smerge-diff-mine-other
  'smerge-diff-upper-lower "26.1")

(defun smerge-match-conflict ()
  "Get info about the conflict.  Puts the info in the `match-data'.
The submatches contain:
 0:  the whole conflict.
 1:  upper version of the code.
 2:  base version of the code.
 3:  lower version of the code.
An error is raised if not inside a conflict."
  (save-excursion
    (condition-case nil
	(let* ((orig-point (point))

	       (_ (forward-line 1))
	       (_ (re-search-backward smerge-begin-re))

	       (start (match-beginning 0))
	       (upper-start (match-end 0))
	       (filename (or (match-string 1) ""))

	       (_ (re-search-forward smerge-end-re))
	       (_ (when (< (match-end 0) orig-point)
	            ;; Point is not within the conflict we found,
                    ;; so this conflict is not ours.
	            (signal 'search-failed (list smerge-begin-re))))

	       (lower-end (match-beginning 0))
	       (end (match-end 0))

	       (_ (re-search-backward smerge-lower-re start))

	       (upper-end (match-beginning 0))
	       (lower-start (match-end 0))

	       base-start base-end)

	  ;; handle the various conflict styles
	  (cond
	   ((save-excursion
	      (goto-char upper-start)
	      (re-search-forward smerge-begin-re end t))
	    ;; There's a nested conflict and we're after the beginning
	    ;; of the outer one but before the beginning of the inner one.
	    ;; Of course, maybe this is not a nested conflict but in that
	    ;; case it can only be something nastier that we don't know how
	    ;; to handle, so may as well arbitrarily decide to treat it as
	    ;; a nested conflict.  --Stef
	    (error "There is a nested conflict"))

	   ((re-search-backward smerge-base-re start t)
	    ;; a 3-parts conflict
            (setq-local smerge-conflict-style 'diff3-A)
	    (setq base-end upper-end)
	    (setq upper-end (match-beginning 0))
	    (setq base-start (match-end 0)))

	   ((string= filename (file-name-nondirectory
			       (or buffer-file-name "")))
	    ;; a 2-parts conflict
            (setq-local smerge-conflict-style 'diff3-E))

	   ((and (not base-start)
		 (or (eq smerge-conflict-style 'diff3-A)
		     (equal filename "ANCESTOR")
		     (string-match "\\`[.0-9]+\\'" filename)))
	    ;; a same-diff conflict
	    (setq base-start upper-start)
	    (setq base-end   upper-end)
	    (setq upper-start lower-start)
	    (setq upper-end   lower-end)))

	  (store-match-data (list start end
				  upper-start upper-end
				  base-start base-end
				  lower-start lower-end
				  (when base-start (1- base-start)) base-start
				  (1- lower-start) lower-start))
	  t)
      (search-failed (user-error "Point not in conflict region")))))

(defun smerge-conflict-overlay (pos)
  "Return the conflict overlay at POS if any."
  (let ((ols (overlays-at pos))
        conflict)
    (dolist (ol ols)
      (if (and (eq (overlay-get ol 'smerge) 'conflict)
               (> (overlay-end ol) pos))
          (setq conflict ol)))
    conflict))

(defun smerge-find-conflict (&optional limit)
  "Find and match a conflict region.  Intended as a font-lock MATCHER.
The submatches are the same as in `smerge-match-conflict'.
Returns non-nil if a match is found between point and LIMIT.
Point is moved to the end of the conflict."
  (let ((found nil)
        (pos (point))
        conflict)
    ;; First check to see if point is already inside a conflict, using
    ;; the conflict overlays.
    (while (and (not found) (setq conflict (smerge-conflict-overlay pos)))
      ;; Check the overlay's validity and kill it if it's out of date.
      (condition-case nil
          (progn
            (goto-char (overlay-start conflict))
            (smerge-match-conflict)
            (goto-char (match-end 0))
            (if (<= (point) pos)
                (error "Matching backward!")
              (setq found t)))
        (error (smerge-remove-props
                (overlay-start conflict) (overlay-end conflict))
               (goto-char pos))))
    ;; If we're not already inside a conflict, look for the next conflict
    ;; and add/update its overlay.
    (while (and (not found) (re-search-forward smerge-begin-re limit t))
      (condition-case nil
          (progn
            (smerge-match-conflict)
            (goto-char (match-end 0))
            (let ((conflict (smerge-conflict-overlay (1- (point)))))
              (if conflict
                  ;; Update its location, just in case it got messed up.
                  (move-overlay conflict (match-beginning 0) (match-end 0))
                (setq conflict (make-overlay (match-beginning 0) (match-end 0)
                                             nil 'front-advance nil))
                (overlay-put conflict 'evaporate t)
                (overlay-put conflict 'smerge 'conflict)
                (let ((props smerge-text-properties))
                  (while props
                    (overlay-put conflict (pop props) (pop props))))))
            (setq found t))
        (error nil)))
    found))

;;; Refined change highlighting

(defvar smerge-refine-forward-function #'smerge--refine-forward
  "Function used to determine an \"atomic\" element.
You can set it to `forward-char' to get char-level granularity.
Its behavior has mainly two restrictions:
- if this function encounters a newline, it's important that it stops right
  after the newline.
  This only matters if `smerge-refine-ignore-whitespace' is nil.
- it needs to be unaffected by changes performed by the `preproc' argument
  to `smerge-refine-regions'.
  This only matters if `smerge-refine-weight-hack' is nil.")

(defvar smerge-refine-ignore-whitespace t
  "If non-nil, `smerge-refine' should try to ignore change in whitespace.")

(defvar smerge-refine-weight-hack t
  "If non-nil, pass to diff as many lines as there are chars in the region.
I.e. each atomic element (e.g. word) will be copied as many times (on different
lines) as it has chars.  This has two advantages:
- if `diff' tries to minimize the number *lines* (rather than chars)
  added/removed, this adjust the weights so that adding/removing long
  symbols is considered correspondingly more costly.
- `smerge-refine-forward-function' only needs to be called when chopping up
  the regions, and `forward-char' can be used afterwards.
It has the following disadvantages:
- cannot use `diff -w' because the weighting causes added spaces in a line
  to be represented as added copies of some line, so `diff -w' can't do the
  right thing any more.
- Is a bit more costly (may in degenerate cases use temp files that are 10x
  larger than the refined regions).")

(defun smerge--refine-forward (n)
  (let ((case-fold-search nil)
        (re "[[:upper:]]?[[:lower:]]+\\|[[:upper:]]+\\|[[:digit:]]+\\|.\\|\n"))
    (when (and smerge-refine-ignore-whitespace
               ;; smerge-refine-weight-hack causes additional spaces to
               ;; appear as additional lines as well, so even if diff ignores
               ;; whitespace changes, it'll report added/removed lines :-(
               (not smerge-refine-weight-hack))
      (setq re (concat "[ \t]*\\(?:" re "\\)")))
    (dotimes (_i n)
      (unless (looking-at re) (error "Smerge refine internal error"))
      (goto-char (match-end 0)))))

(defvar smerge--refine-long-words)

(defun smerge--refine-chopup-region (beg end file &optional preproc)
  "Chopup the region into small elements, one per line.
Save the result into FILE.
If non-nil, PREPROC is called with no argument in a buffer that contains
a copy of the text, just before chopping it up.  It can be used to replace
chars to try and eliminate some spurious differences."
  ;; We used to chop up char-by-char rather than word-by-word like ediff
  ;; does.  It had the benefit of simplicity and very fine results, but it
  ;; often suffered from problem that diff would find correlations where
  ;; there aren't any, so the resulting "change" didn't make much sense.
  ;; You can still get this behavior by setting
  ;; `smerge-refine-forward-function' to `forward-char'.
  (with-temp-buffer
    (insert-buffer-substring (marker-buffer beg) beg end)
    (when preproc (goto-char (point-min)) (funcall preproc))
    (when smerge-refine-ignore-whitespace
      ;; It doesn't make much of a difference for diff-fine-highlight
      ;; because we still have the _/+/</>/! prefix anyway.  Can still be
      ;; useful in other circumstances.
      (subst-char-in-region (point-min) (point-max) ?\n ?\s))
    (goto-char (point-min))
    (while (not (eobp))
      (cl-assert (bolp))
      (let ((start (point)))
        (funcall smerge-refine-forward-function 1)
        (let ((len (- (point) start)))
          (cl-assert (>= len 1))
          ;; We add \n after each chunk except after \n, so we get
          ;; one line per text chunk, where each line contains
          ;; just one chunk, except for \n chars which are
          ;; represented by the empty line.
          (unless (bolp) (insert ?\n))
          (when (and smerge-refine-weight-hack (> len 1))
            (let ((s (buffer-substring-no-properties start (point))))
              ;; The weight-hack inserts N copies of words of size N,
              ;; so it naturally suffers from an O(N²) blow up.
              ;; To circumvent this, we map each long word
              ;; to a shorter (but still unique) replacement.
              ;; Another option would be to change smerge--refine-forward
              ;; so it chops up long words into smaller ones.
              (when (> len 8)
                (let ((short (gethash s smerge--refine-long-words)))
                  (unless short
                    ;; To avoid accidental conflicts with ≤8 words,
                    ;; we make sure the replacement is >8 chars.  Overall,
                    ;; this should bound the blowup factor to ~10x,
                    ;; tho if those chars end up encoded as multiple bytes
                    ;; each, it could probably still reach ~30x in
                    ;; pathological cases.
                    (setq short
                          (concat (substring s 0 7)
                                  " "
                                  (string
                                   (+ ?0
                                      (hash-table-count
                                       smerge--refine-long-words)))
                                  "\n"))
                    (puthash s short smerge--refine-long-words))
                  (delete-region start (point))
                  (insert short)
                  (setq s short)))
              (dotimes (_i (1- len)) (insert s)))))))
    (unless (bolp) (error "Smerge refine internal error"))
    (let ((coding-system-for-write 'utf-8-emacs-unix))
      (write-region (point-min) (point-max) file nil 'nomessage))))

(defun smerge--refine-highlight-change (beg match-num1 match-num2 props)
  ;; TODO: Add a property pointing to the corresponding text in the
  ;; other region.
  (with-current-buffer (marker-buffer beg)
    (goto-char beg)
    (let* ((startline (- (string-to-number match-num1) 1))
           (beg (progn (funcall (if smerge-refine-weight-hack
                                    #'forward-char
                                  smerge-refine-forward-function)
                                startline)
                       (point)))
           (end (progn (funcall (if smerge-refine-weight-hack
                                    #'forward-char
                                  smerge-refine-forward-function)
                          (if match-num2
                              (- (string-to-number match-num2)
                                 startline)
                            1))
                       (point))))
      (when smerge-refine-ignore-whitespace
        (skip-chars-backward " \t\n" beg) (setq end (point))
        (goto-char beg)
        (skip-chars-forward " \t\n" end)  (setq beg (point)))
      (when (> end beg)
        (let ((ol (make-overlay
                   beg end nil
                   ;; Make them tend to shrink rather than spread when editing.
                   'front-advance nil)))
          (overlay-put ol 'evaporate t)
          (dolist (x props) (overlay-put ol (car x) (cdr x)))
          ol)))))

;;;###autoload
(defun smerge-refine-regions (beg1 end1 beg2 end2 props-c &optional preproc props-r props-a)
  "Show fine differences in the two regions BEG1..END1 and BEG2..END2.
PROPS-C is an alist of properties to put (via overlays) on the changes.
PROPS-R is an alist of properties to put on removed characters.
PROPS-A is an alist of properties to put on added characters.
If PROPS-R and PROPS-A are nil, put PROPS-C on all changes.
If PROPS-C is nil, but PROPS-R and PROPS-A are non-nil,
put PROPS-A on added characters, PROPS-R on removed characters.
If PROPS-C, PROPS-R and PROPS-A are non-nil, put PROPS-C on changed characters,
PROPS-A on added characters, and PROPS-R on removed characters.

If non-nil, PREPROC is called with no argument in a buffer that contains
a copy of a region, just before preparing it to for `diff'.  It can be
used to replace chars to try and eliminate some spurious differences."
  (let* ((pos (point))
         deactivate-mark         ; The code does not modify any visible buffer.
         (file1 (make-temp-file "diff1"))
         (file2 (make-temp-file "diff2"))
         (smerge--refine-long-words
          (if smerge-refine-weight-hack (make-hash-table :test #'equal))))
    (unless (markerp beg1) (setq beg1 (copy-marker beg1)))
    (unless (markerp beg2) (setq beg2 (copy-marker beg2)))
    (let ((write-region-inhibit-fsync t)) ; Don't fsync temp files (Bug#12747).
      ;; Chop up regions into smaller elements and save into files.
      (smerge--refine-chopup-region beg1 end1 file1 preproc)
      (smerge--refine-chopup-region beg2 end2 file2 preproc))

    ;; Call diff on those files.
    (unwind-protect
        (with-temp-buffer
          ;; Allow decoding the EOL format, as on MS-Windows the Diff
          ;; utility might produce CR-LF EOLs.
          (let ((coding-system-for-read 'utf-8-emacs))
            (call-process diff-command nil t nil
                          (if (and smerge-refine-ignore-whitespace
                                   (not smerge-refine-weight-hack))
                              ;; Pass -a so diff treats it as a text file even
                              ;; if it contains \0 and such.
                              ;; Pass -d so as to get the smallest change, but
                              ;; also and more importantly because otherwise it
                              ;; may happen that diff doesn't behave like
                              ;; smerge-refine-weight-hack expects it to.
                              ;; See https://lists.gnu.org/r/emacs-devel/2007-11/msg00401.html
                              "-awd" "-ad")
                          file1 file2))
          ;; Process diff's output.
          (goto-char (point-min))
          (let ((last1 nil)
                (last2 nil))
            (while (not (eobp))
              (if (not (looking-at "\\([0-9]+\\)\\(?:,\\([0-9]+\\)\\)?\\([acd]\\)\\([0-9]+\\)\\(?:,\\([0-9]+\\)\\)?$"))
                  (error "Unexpected patch hunk header: %s"
                         (buffer-substring (point) (line-end-position))))
              (let ((op (char-after (match-beginning 3)))
                    (m1 (match-string 1))
                    (m2 (match-string 2))
                    (m4 (match-string 4))
                    (m5 (match-string 5)))
                (when (memq op '(?d ?c))
                  (setq last1
                        (smerge--refine-highlight-change
			 beg1 m1 m2
			 ;; Try to use props-c only for changed chars,
			 ;; fallback to props-r for changed/removed chars,
			 ;; but if props-r is nil then fallback to props-c.
			 (or (and (eq op '?c) props-c) props-r props-c))))
                (when (memq op '(?a ?c))
                  (setq last2
                        (smerge--refine-highlight-change
			 beg2 m4 m5
			 ;; Same logic as for removed chars above.
			 (or (and (eq op '?c) props-c) props-a props-c)))))
              (forward-line 1)                            ;Skip hunk header.
              (and (re-search-forward "^[0-9]" nil 'move) ;Skip hunk body.
                   (goto-char (match-beginning 0))))
            ;; (cl-assert (or (null last1) (< (overlay-start last1) end1)))
            ;; (cl-assert (or (null last2) (< (overlay-start last2) end2)))
            (if smerge-refine-weight-hack
                (progn
                  ;; (cl-assert (or (null last1) (<= (overlay-end last1) end1)))
                  ;; (cl-assert (or (null last2) (<= (overlay-end last2) end2)))
                  )
              ;; smerge-refine-forward-function when calling in chopup may
              ;; have stopped because it bumped into EOB whereas in
              ;; smerge-refine-weight-hack it may go a bit further.
              (if (and last1 (> (overlay-end last1) end1))
                  (move-overlay last1 (overlay-start last1) end1))
              (if (and last2 (> (overlay-end last2) end2))
                  (move-overlay last2 (overlay-start last2) end2))
              )))
      (goto-char pos)
      (delete-file file1)
      (delete-file file2))))
(define-obsolete-function-alias 'smerge-refine-subst
  #'smerge-refine-regions "26.1")

(defun smerge-refine (&optional part)
  "Highlight the words of the conflict that are different.
For 3-way conflicts, highlights only two of the three parts.
A numeric argument PART can be used to specify which two parts;
repeating the command will highlight other two parts."
  (interactive
   (if (integerp current-prefix-arg) (list current-prefix-arg)
     (smerge-match-conflict)
     (let* ((prop (get-text-property (match-beginning 0) 'smerge-refine-part))
            (part (if (and (consp prop)
                           (eq (buffer-chars-modified-tick) (car prop)))
                      (cdr prop))))
       ;; If already highlighted, cycle.
       (list (if (integerp part) (1+ (mod part 3)))))))

  (if (and (integerp part) (or (< part 1) (> part 3)))
      (error "No conflict part nb %s" part))
  (smerge-match-conflict)
  (remove-overlays (match-beginning 0) (match-end 0) 'smerge 'refine)
  ;; Ignore `part' if not applicable, and default it if not provided.
  (setq part (cond ((null (match-end 2)) 2)
                   ((eq (match-end 1) (match-end 3)) 1)
                   ((integerp part) part)
                   ;; If one of the parts is empty, any refinement using
                   ;; it will be trivial and uninteresting.
                   ((eq (match-end 1) (match-beginning 1)) 1)
                   ((eq (match-end 3) (match-beginning 3)) 3)
                   (t 2)))
  (let ((n1 (if (eq part 1) 2 1))
        (n2 (if (eq part 3) 2 3))
	(smerge-use-changed-face
	 (and (face-differs-from-default-p 'smerge-refined-change)
	      (not (face-equal 'smerge-refined-change 'smerge-refined-added))
	      (not (face-equal 'smerge-refined-change 'smerge-refined-removed)))))
    (smerge-ensure-match n1)
    (smerge-ensure-match n2)
    (with-silent-modifications
      (put-text-property (match-beginning 0) (1+ (match-beginning 0))
                         'smerge-refine-part
                         (cons (buffer-chars-modified-tick) part)))
    (smerge-refine-regions (match-beginning n1) (match-end n1)
                         (match-beginning n2)  (match-end n2)
                         (if smerge-use-changed-face
			     '((smerge . refine) (font-lock-face . smerge-refined-change)))
			 nil
			 (unless smerge-use-changed-face
			   '((smerge . refine) (font-lock-face . smerge-refined-removed)))
			 (unless smerge-use-changed-face
			   '((smerge . refine) (font-lock-face . smerge-refined-added))))))

(defun smerge-swap ()
  "Swap the \"Upper\" and the \"Lower\" chunks.
Can be used before things like `smerge-keep-all' or `smerge-resolve' where the
ordering can have some subtle influence on the result, such as preferring the
spacing of the \"Lower\" chunk."
  (interactive)
  (smerge-match-conflict)
  (goto-char (match-beginning 3))
  (let ((txt3 (delete-and-extract-region (point) (match-end 3))))
    (insert (delete-and-extract-region (match-beginning 1) (match-end 1)))
    (goto-char (match-beginning 1))
    (insert txt3)))

(defun smerge-diff (n1 n2)
  (smerge-match-conflict)
  (smerge-ensure-match n1)
  (smerge-ensure-match n2)
  (let ((name1 (aref smerge-match-names n1))
	(name2 (aref smerge-match-names n2))
	;; Read them before the match-data gets clobbered.
	(beg1 (match-beginning n1))
	(end1 (match-end n1))
	(beg2 (match-beginning n2))
	(end2 (match-end n2))
	(file1 (make-temp-file "smerge1"))
	(file2 (make-temp-file "smerge2"))
	(dir default-directory)
	(file (if buffer-file-name (file-relative-name buffer-file-name)))
        ;; We would want to use `emacs-mule-unix' for read&write, but we
        ;; bump into problems with the coding-system used by diff to write
        ;; the file names and the time stamps in the header.
        ;; `buffer-file-coding-system' is not always correct either, but if
        ;; the OS/user uses only one coding-system, then it works.
	(coding-system-for-read buffer-file-coding-system))
    (write-region beg1 end1 file1 nil 'nomessage)
    (write-region beg2 end2 file2 nil 'nomessage)
    (unwind-protect
	(with-current-buffer (get-buffer-create smerge-diff-buffer-name)
	  (setq default-directory dir)
	  (let ((inhibit-read-only t))
	    (erase-buffer)
	    (let ((status
		   (apply 'call-process diff-command nil t nil
			  (append smerge-diff-switches
				  (and (diff-check-labels)
				       (list "--label"
					     (concat name1 "/" file)
					     "--label"
					     (concat name2 "/" file)))
				  (list file1 file2)))))
	      (if (eq status 0) (insert "No differences found.\n"))))
	  (goto-char (point-min))
	  (diff-mode)
	  (display-buffer (current-buffer) t))
      (delete-file file1)
      (delete-file file2))))

;; compiler pacifiers
(defvar smerge-ediff-windows)
(defvar smerge-ediff-buf)
(defvar ediff-buffer-A)
(defvar ediff-buffer-B)
(defvar ediff-buffer-C)
(defvar ediff-ancestor-buffer)
(defvar ediff-quit-hook)
(declare-function ediff-cleanup-mess "ediff-util" nil)

(defun smerge--get-marker (regexp default)
  (save-excursion
    (goto-char (point-min))
    (if (and (search-forward-regexp regexp nil t)
	     (> (match-end 1) (match-beginning 1)))
	(concat default "=" (match-string-no-properties 1))
      default)))

;;;###autoload
(defun smerge-ediff (&optional name-upper name-lower name-base)
  "Invoke ediff to resolve the conflicts.
NAME-UPPER, NAME-LOWER, and NAME-BASE, if non-nil, are used for the
buffer names."
  (interactive)
  (let* ((buf (current-buffer))
	 (mode major-mode)
	 ;;(ediff-default-variant 'default-B)
	 (config (current-window-configuration))
	 (filename (file-name-nondirectory (or buffer-file-name "-")))
	 (upper (generate-new-buffer
		(or name-upper
                    (concat "*" filename " "
                            (smerge--get-marker smerge-begin-re "UPPER")
                            "*"))))
	 (lower (generate-new-buffer
		 (or name-lower
                     (concat "*" filename " "
                             (smerge--get-marker smerge-end-re "LOWER")
                             "*"))))
	 base)
    (with-current-buffer upper
      (buffer-disable-undo)
      (insert-buffer-substring buf)
      (goto-char (point-min))
      (while (smerge-find-conflict)
	(when (match-beginning 2) (setq base t))
	(smerge-keep-n 1))
      (buffer-enable-undo)
      (set-buffer-modified-p nil)
      (funcall mode))

    (with-current-buffer lower
      (buffer-disable-undo)
      (insert-buffer-substring buf)
      (goto-char (point-min))
      (while (smerge-find-conflict)
	(smerge-keep-n 3))
      (buffer-enable-undo)
      (set-buffer-modified-p nil)
      (funcall mode))

    (when base
      (setq base (generate-new-buffer
		  (or name-base
                      (concat "*" filename " "
                              (smerge--get-marker smerge-base-re "BASE")
                              "*"))))
      (with-current-buffer base
	(buffer-disable-undo)
	(insert-buffer-substring buf)
	(goto-char (point-min))
	(while (smerge-find-conflict)
	  (if (match-end 2)
	      (smerge-keep-n 2)
	    (delete-region (match-beginning 0) (match-end 0))))
	(buffer-enable-undo)
	(set-buffer-modified-p nil)
	(funcall mode)))

    ;; the rest of the code is inspired from vc.el
    ;; Fire up ediff.
    (set-buffer
     (if base
	 (ediff-merge-buffers-with-ancestor upper lower base)
	  ;; nil 'ediff-merge-revisions-with-ancestor buffer-file-name)
       (ediff-merge-buffers upper lower)))
        ;; nil 'ediff-merge-revisions buffer-file-name)))

    ;; Ediff is now set up, and we are in the control buffer.
    ;; Do a few further adjustments and take precautions for exit.
    (setq-local smerge-ediff-windows config)
    (setq-local smerge-ediff-buf buf)
    (add-hook 'ediff-quit-hook
	      (lambda ()
		(let ((buffer-A ediff-buffer-A)
		      (buffer-B ediff-buffer-B)
		      (buffer-C ediff-buffer-C)
		      (buffer-Ancestor ediff-ancestor-buffer)
		      (buf smerge-ediff-buf)
		      (windows smerge-ediff-windows))
		  (ediff-cleanup-mess)
		  (with-current-buffer buf
		    (erase-buffer)
		    (insert-buffer-substring buffer-C)
		    (kill-buffer buffer-A)
		    (kill-buffer buffer-B)
		    (kill-buffer buffer-C)
		    (when (bufferp buffer-Ancestor)
		      (kill-buffer buffer-Ancestor))
		    (set-window-configuration windows)
		    (message "Conflict resolution finished; you may save the buffer"))))
	      nil t)
    (message "Please resolve conflicts now; exit ediff when done")))

(defun smerge-makeup-conflict (pt1 pt2 pt3 &optional pt4)
  "Insert diff3 markers to make a new conflict.
Uses point and mark for two of the relevant positions and previous marks
for the other ones.
By default, makes up a 2-way conflict,
with a \\[universal-argument] prefix, makes up a 3-way conflict."
  (interactive
   (list (point)
         (mark)
         (progn (pop-mark) (mark))
         (when current-prefix-arg (pop-mark) (mark))))
  ;; Start from the end so as to avoid problems with pos-changes.
  (pcase-let ((`(,pt1 ,pt2 ,pt3 ,pt4)
               (sort `(,pt1 ,pt2 ,pt3 ,@(if pt4 (list pt4))) '>=)))
    (goto-char pt1) (beginning-of-line)
    (insert ">>>>>>> LOWER\n")
    (goto-char pt2) (beginning-of-line)
    (insert "=======\n")
    (goto-char pt3) (beginning-of-line)
    (when pt4
      (insert "||||||| BASE\n")
      (goto-char pt4) (beginning-of-line))
    (insert "<<<<<<< UPPER\n"))
  (if smerge-mode nil (smerge-mode 1))
  (smerge-refine))


(defconst smerge-parsep-re
  (concat smerge-begin-re "\\|" smerge-end-re "\\|"
          smerge-base-re "\\|" smerge-lower-re "\\|"))

;;;###autoload
(define-minor-mode smerge-mode
  "Minor mode to simplify editing output from the diff3 program.

\\{smerge-mode-map}"
  :group 'smerge :lighter " SMerge"
  (when font-lock-mode
    (save-excursion
      (if smerge-mode
	  (font-lock-add-keywords nil smerge-font-lock-keywords 'append)
	(font-lock-remove-keywords nil smerge-font-lock-keywords))
      (goto-char (point-min))
      (while (smerge-find-conflict)
	(save-excursion
	  (font-lock-fontify-region (match-beginning 0) (match-end 0) nil)))))
  (if (string-match (regexp-quote smerge-parsep-re) paragraph-separate)
      (unless smerge-mode
        (setq-local paragraph-separate
                    (replace-match "" t t paragraph-separate)))
    (when smerge-mode
        (setq-local paragraph-separate
                    (concat smerge-parsep-re paragraph-separate))))
  (unless smerge-mode
    (smerge-remove-props (point-min) (point-max))))

;;;###autoload
(defun smerge-start-session (&optional interactively)
  "Turn on `smerge-mode' and move point to first conflict marker.
If no conflict maker is found, turn off `smerge-mode'."
  (interactive "p")
  (when (or (null smerge-mode) interactively)
    (smerge-mode 1)
    (condition-case nil
        (unless (looking-at smerge-begin-re)
          (smerge-next))
      (error (smerge-auto-leave)))))

(defcustom smerge-change-buffer-confirm t
  "If non-nil, request confirmation before moving to another buffer."
  :type 'boolean)

(defun smerge-vc-next-conflict ()
  "Go to next conflict, possibly in another file.
First tries to go to the next conflict in the current buffer, and if not
found, uses VC to try and find the next file with conflict."
  (interactive)
  (condition-case nil
      ;; FIXME: Try again from BOB before moving to the next file.
      (smerge-next)
    (error
     (if (and (or smerge-change-buffer-confirm
                  (and (buffer-modified-p) buffer-file-name))
              (not (or (eq last-command this-command)
                       (eq ?\r last-command-event)))) ;Called via M-x!?
         ;; FIXME: Don't emit this message if `vc-find-conflicted-file' won't
         ;; go to another file anyway (because there are no more conflicted
         ;; files).
         (message (if (buffer-modified-p)
                      "No more conflicts here.  Repeat to save and go to next buffer"
                    "No more conflicts here.  Repeat to go to next buffer"))
       (if (and (buffer-modified-p) buffer-file-name)
           (save-buffer))
       (vc-find-conflicted-file)
       ;; At this point, the caret will only be at a conflict marker
       ;; if the file did not correspond to an opened
       ;; buffer. Otherwise we need to jump to a marker explicitly.
       (unless (looking-at "^<<<<<<<")
         (let ((prev-pos (point)))
           (goto-char (point-min))
           (unless (ignore-errors (not (smerge-next)))
             (goto-char prev-pos))))))))

(provide 'smerge-mode)

;;; smerge-mode.el ends here

debug log:

solving 694d4529b9 ...
found 694d4529b9 in https://git.savannah.gnu.org/cgit/emacs.git

(*) Git path names are given by the tree(s) the blob belongs to.
    Blobs themselves have no identifier aside from the hash of its contents.^

Code repositories for project(s) associated with this public inbox

	https://git.savannah.gnu.org/cgit/emacs.git

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).