Index: usr.bin/diff3/diff3.1
===================================================================
--- usr.bin/diff3/diff3.1
+++ usr.bin/diff3/diff3.1
@@ -30,7 +30,7 @@
 .\"     @(#)diff3.1	8.2 (Berkeley) 4/18/94
 .\" $FreeBSD$
 .\"
-.Dd August 23, 2021
+.Dd March 2, 2022
 .Dt DIFF3 1
 .Os
 .Sh NAME
@@ -38,7 +38,7 @@
 .Nd 3-way differential file comparison
 .Sh SYNOPSIS
 .Nm diff3
-.Op Fl 3aEeiTXx
+.Op Fl 3aAEeimTXx
 .Op Fl Fl diff-program Ar program
 .Op Fl Fl strip-trailing-cr
 .Op Fl L | Fl Fl label Ar label1
@@ -73,6 +73,8 @@
 .Ar file3 .
 .It Fl a , Fl Fl text
 Treat all files as ASCII.
+.It Fl A Fl Fl show-all
+Output all changes, bracketing conflicts.
 .It Fl E , Fl Fl show-overlap
 .It Fl X
 Similar to
@@ -115,6 +117,8 @@
 .Ar file2
 and
 .Ar file3 .
+.It Fl m, Fl Fl merge
+Merge output instead of generating ed script (default .FL A)
 .It Fl T, Fl Fl initial-tab
 In the normal listing,
 use a tab instead of two spaces
Index: usr.bin/diff3/diff3.c
===================================================================
--- usr.bin/diff3/diff3.c
+++ usr.bin/diff3/diff3.c
@@ -100,6 +100,12 @@
 };
 
 struct diff {
+#define DIFF_TYPE2 2
+#define DIFF_TYPE3 3
+	int type;
+	char *line;		// REMOVE: helps with debugging 
+
+	/* Ranges as lines */
 	struct range old;
 	struct range new;
 };
@@ -110,10 +116,9 @@
 static struct diff *d23;
 /*
  * "de" is used to gather editing scripts.  These are later spewed out in
- * reverse order.  Its first element must be all zero, the "new" component
- * of "de" contains line positions or byte positions depending on when you
- * look (!?).  Array overlap indicates which sections in "de" correspond to
- * lines that are different in all three files.
+ * reverse order.  Its first element must be all zero, the "old" and "new"
+ * components1 of "de" contain line positions. Array overlap indicates which
+ * sections in "de" correspond to lines that are different in all three files.
  */
 static struct diff *de;
 static char *overlap;
@@ -129,9 +134,12 @@
 static int oflag;		/* indicates whether to mark overlaps (-E or -X) */
 static int strip_cr;
 static char *f1mark, *f2mark, *f3mark;
+static const char *oldmark = "<<<<<<<";
+static const char *orgmark = "|||||||";
+static const char *newmark = ">>>>>>>";
 
 static bool duplicate(struct range *, struct range *);
-static int edit(struct diff *, bool, int);
+static int edit(struct diff *, bool, int, int);
 static char *getchange(FILE *);
 static char *get_line(FILE *, size_t *);
 static int readin(int fd, struct diff **);
@@ -139,11 +147,14 @@
 static void change(int, struct range *, bool);
 static void keep(int, struct range *);
 static void merge(int, int);
-static void prange(struct range *);
+static void prange(struct range *, int);
 static void repos(int);
 static void edscript(int) __dead2;
+static void Ascript(int) __dead2;
+static void mergescript(int) __dead2;
 static void increase(void);
 static void usage(void) __dead2;
+static void printrange(FILE *, struct range *);
 
 enum {
 	DIFFPROG_OPT,
@@ -187,6 +198,8 @@
 	if (f == NULL)
 		err(2, "fdopen");
 	for (i = 0; (p = getchange(f)); i++) {
+		(*dd)[i].line = strdup(p);	//REMOVE helps with debugging 
+
 		if (i >= szchanges - 1)
 			increase();
 		a = b = (int)strtoimax(p, &p, 10);
@@ -300,6 +313,7 @@
 			d1++;
 			continue;
 		}
+
 		/* second file is different from others */
 		if (!t1 || (t2 && d2->new.to < d1->new.from)) {
 			if (eflag == 0) {
@@ -307,6 +321,9 @@
 				keep(1, &d2->new);
 				change(3, &d2->new, false);
 				change(2, &d2->old, false);
+			} else if (Aflag || mflag) {
+				// TODO What does it mean for the second file to differ?
+				j = edit(d2, dup, j, DIFF_TYPE2);
 			}
 			d2++;
 			continue;
@@ -342,8 +359,10 @@
 				change(2, &d2->old, false);
 				d3 = d1->old.to > d1->old.from ? d1 : d2;
 				change(3, &d3->new, false);
-			} else
-				j = edit(d1, dup, j);
+			} else {
+				j = edit(d1, dup, j, DIFF_TYPE3);
+			}
+			dup = false;
 			d1++;
 			d2++;
 			continue;
@@ -367,7 +386,12 @@
 			d1->new.to = d2->new.to;
 		}
 	}
-	if (eflag)
+
+	if (mflag)
+		mergescript(j);
+	else if (Aflag)
+		Ascript(j);
+	else if (eflag)
 		edscript(j);
 }
 
@@ -382,7 +406,7 @@
 
 	printf("%d:", i);
 	last[i] = rold->to;
-	prange(rold);
+	prange(rold, 0);
 	if (dup)
 		return;
 	i--;
@@ -395,7 +419,7 @@
  * n1.
  */
 static void
-prange(struct range *rold)
+prange(struct range *rold, int delete)
 {
 
 	if (rold->to <= rold->from)
@@ -404,7 +428,10 @@
 		printf("%d", rold->from);
 		if (rold->to > rold->from + 1)
 			printf(",%d", rold->to - 1);
-		printf("c\n");
+		if (delete)
+			printf("d\n");
+		else
+			printf("c\n");
 	}
 }
 
@@ -432,7 +459,7 @@
 static int
 skip(int i, int from, const char *pr)
 {
-	size_t j, n;
+	size_t j = 0, n;
 	char *line;
 
 	for (n = 0; cline[i] < from - 1; n += j) {
@@ -493,68 +520,77 @@
  * collect an editing script for later regurgitation
  */
 static int
-edit(struct diff *diff, bool dup, int j)
+edit(struct diff *diff, bool dup, int j, int difftype)
 {
-
 	if (((dup + 1) & eflag) == 0)
 		return (j);
 	j++;
 	overlap[j] = !dup;
 	if (!dup)
 		overlapcnt++;
+
+	de[j].type = difftype;
+	de[j].line = diff->line;		// REMOVE 
+
 	de[j].old.from = diff->old.from;
 	de[j].old.to = diff->old.to;
-	de[j].new.from = de[j-1].new.to + skip(2, diff->new.from, NULL);
-	de[j].new.to = de[j].new.from + skip(2, diff->new.to, NULL);
+	de[j].new.from = diff->new.from;
+	de[j].new.to = diff->new.to;
+
 	return (j);
 }
 
+static void
+printrange(FILE *p, struct range *r)
+{
+	char *line = NULL;
+	size_t len = 0;
+	int i = 1;
+	ssize_t rlen = 0;
+
+	/* We haven't been asked to print anything */
+	if (r->from == r->to)
+		return;
+
+	if (r->from > r->to)
+			errx(EXIT_FAILURE, "invalid print range");
+
+	/*
+	 * XXXTHHXXX: We are read through all of each file for each range
+	 * printed which is less than optimal.
+	 */
+	fseek(p, 0L, SEEK_SET);
+	while((rlen = getline(&line, &len, p)) > 0) {
+		if (i >= r->from)
+			printf("%s", line);
+		free(line);
+		line = NULL;
+		len = 0;
+		if (++i > r->to-1)
+			break;
+	}
+}
+
 /* regurgitate */
 static void
 edscript(int n)
 {
-	int k;
-	size_t j;
-	char block[BUFSIZ];
-
 	for (; n > 0; n--) {
+		int delete = (de[n].new.from == de[n].new.to);
 		if (!oflag || !overlap[n]) {
-			prange(&de[n].old);
+			prange(&de[n].old, delete);
 		} else {
 			printf("%da\n", de[n].old.to - 1);
-			if (Aflag) {
-				printf("%s\n", f2mark);
-				fseek(fp[1], de[n].old.from, SEEK_SET);
-				for (k = de[n].old.to - de[n].old.from; k > 0; k -= j) {
-					j = k > BUFSIZ ? BUFSIZ : k;
-					if (fread(block, 1, j, fp[1]) != j)
-						errx(2, "logic error");
-					fwrite(block, 1, j, stdout);
-				}
-				printf("\n");
-			}
 			printf("=======\n");
 		}
-		fseek(fp[2], (long)de[n].new.from, SEEK_SET);
-		for (k = de[n].new.to - de[n].new.from; k > 0; k -= j) {
-			size_t r;
-
-			j = k > BUFSIZ ? BUFSIZ : k;
-			r = fread(block, 1, j, fp[2]);
-			if (r == 0) {
-				if (feof(fp[2]))
-					break;
-				errx(2, "logic error");
-			}
-			if (r != j)
-				j = r;
-			(void)fwrite(block, 1, j, stdout);
-		}
-		if (!oflag || !overlap[n])
-			printf(".\n");
-		else {
-			printf("%s\n.\n", f3mark);
-			printf("%da\n%s\n.\n", de[n].old.from - 1, f1mark);
+		printrange(fp[2], &de[n].new);
+		if (!oflag || !overlap[n]) {
+			if (!delete)
+				printf(".\n");
+		} else {
+			printf("%s %s\n.\n", newmark, f3mark);
+			printf("%da\n%s %s\n.\n", de[n].old.from - 1,
+				oldmark, f1mark);
 		}
 	}
 	if (iflag)
@@ -563,6 +599,171 @@
 	exit(eflag == 0 ? overlapcnt : 0);
 }
 
+/*
+ * Output an edit script to turn mine into yours, when there is a conflict
+ * between the 3 files bracket the changes. Regurgitate the diffs in reverse
+ * order to allow the ed script to track down where the lines are as changes
+ * are made.
+ */
+static void
+Ascript(int n)
+{
+	int deletenew = 0;
+	int deleteold = 0;
+	int startmark;
+
+	for (; n > 0; n--) {
+
+		deletenew = (de[n].new.from == de[n].new.to);
+		deleteold = (de[n].old.from == de[n].old.to);
+		startmark = de[n].old.from + (de[n].old.to - de[n].old.from) - 1;
+
+		if (de[n].type == DIFF_TYPE2) {
+			if (!oflag || !overlap[n]) {
+				prange(&de[n].old, deletenew);
+				printrange(fp[2], &de[n].new);
+			} else {
+				startmark = de[n].new.from +
+					(de[n].new.to - de[n].new.from);
+
+				if (!deletenew)
+					startmark--;
+
+				printf("%da\n", startmark);
+				printf("%s %s\n", newmark, f3mark);
+
+				printf(".\n");
+
+				printf("%da\n", startmark -
+					(de[n].new.to - de[n].new.from));
+				printf("%s %s\n", oldmark, f2mark);
+				if (!deleteold)
+					printrange(fp[1], &de[n].old);
+				printf("=======\n.\n");
+			}
+
+		} else if (de[n].type == DIFF_TYPE3) {
+			if (!oflag || !overlap[n]) {
+				prange(&de[n].old, deletenew);
+				printrange(fp[2], &de[n].new);
+			} else {
+				printf("%da\n", startmark);
+				printf("%s %s\n", orgmark, f2mark);
+
+				if (deleteold) {
+					struct range r;
+					r.from = de[n].old.from-1;
+					r.to = de[n].new.to;
+					printrange(fp[1], &r);
+				} else
+					printrange(fp[1], &de[n].old);
+
+				printf("=======\n");
+				printrange(fp[2], &de[n].new);
+			}
+
+			if (!oflag || !overlap[n]) {
+				if (!deletenew)
+					printf(".\n");
+			} else {
+				printf("%s %s\n.\n", newmark, f3mark);
+
+				/*
+				 * Go to the start of the conflict in original
+				 * file and append lines
+				 */
+				printf("%da\n%s %s\n.\n",
+					startmark - (de[n].old.to - de[n].old.from),
+					oldmark, f1mark);
+			}
+		}
+	}
+	if (iflag)
+		printf("w\nq\n");
+
+	exit(overlapcnt > 0);
+}
+
+/*
+ * Output the merged file directly (don't generate an ed script). When
+ * regurgitating diffs we need to walk forward through the file and print any
+ * inbetween lines.
+ */
+static void
+mergescript(int i)
+{
+	struct range r;
+	int n;
+
+	r.from = 1;
+	r.to = 1;
+
+	for (n = 1; n < i+1; n++) {
+		/* print any lines leading up to here */
+		r.to = de[n].old.from;
+		printrange(fp[0], &r);
+
+		if (de[n].type == DIFF_TYPE2) {
+			printf("%s %s\n", oldmark, f2mark);
+			printrange(fp[1], &de[n].old);
+			printf("=======\n");
+			printrange(fp[2], &de[n].new);
+			printf("%s %s\n", newmark, f3mark);
+		} else if (de[n].type == DIFF_TYPE3) {
+			if (!oflag || !overlap[n]) {
+				printrange(fp[2], &de[n].new);
+			} else {
+
+				printf("%s %s\n", oldmark, f1mark);
+				printrange(fp[0], &de[n].old);
+
+				printf("%s %s\n", orgmark, f2mark);
+				if (de[n].old.from == de[n].old.to) {
+					struct range or;
+					or.from = de[n].old.from -1;
+					or.to = de[n].new.to;
+					printrange(fp[1], &or);
+				} else
+					printrange(fp[1], &de[n].old);
+
+				printf("=======\n");
+
+				printrange(fp[2], &de[n].new);
+				printf("%s %s\n", newmark, f3mark);
+			}
+		}
+
+		if (de[n].old.from == de[n].old.to)
+			r.from = de[n].new.to;
+		else
+			r.from = de[n].old.to;
+	}
+	/*
+	 * Print from the final range to the end of 'myfile'. Any deletions or
+	 * additions to this file should have been handled by now.
+	 *
+	 * If the ranges are the same we need to rewind a line.
+	 * If the new range is 0 length (from == to), we need to use the old
+	 * range.
+	 */
+	if ((de[n-1].old.from == de[n-1].new.from) &&
+		(de[n-1].old.to == de[n-1].new.to))
+		r.from--;
+	else if (de[n-1].new.from == de[n-1].new.to)
+		r.from = de[n-1].old.from;
+
+	/*
+	 * If the range is a 3 way merge then we need to skip a line in the
+	 * trailing output.
+	 */
+	if (de[n-1].type == DIFF_TYPE3)
+		r.from++;
+
+	r.to = INT_MAX;
+	printrange(fp[0], &r);
+	exit(overlapcnt > 0);
+}
+
 static void
 increase(void)
 {
@@ -697,15 +898,15 @@
 	file3 = argv[2];
 
 	if (oflag) {
-		asprintf(&f1mark, "<<<<<<< %s",
+		asprintf(&f1mark, "%s",
 		    labels[0] != NULL ? labels[0] : file1);
 		if (f1mark == NULL)
 			err(2, "asprintf");
-		asprintf(&f2mark, "||||||| %s",
+		asprintf(&f2mark, "%s",
 		    labels[1] != NULL ? labels[1] : file2);
 		if (f2mark == NULL)
 			err(2, "asprintf");
-		asprintf(&f3mark, ">>>>>>> %s",
+		asprintf(&f3mark, "%s",
 		    labels[2] != NULL ? labels[2] : file3);
 		if (f3mark == NULL)
 			err(2, "asprintf");
Index: usr.bin/diff3/tests/Makefile
===================================================================
--- usr.bin/diff3/tests/Makefile
+++ usr.bin/diff3/tests/Makefile
@@ -9,6 +9,12 @@
 	1cr.txt \
 	2.txt \
 	3.txt \
+	lao.txt \
+	tzu.txt \
+	tao.txt \
+	long-m.txt \
+	long-o.txt \
+	long-y.txt \
 	1.out \
 	1t.out \
 	2.out \
@@ -18,6 +24,12 @@
 	6.out \
 	7.out \
 	8.out \
-	9.out
+	9.out \
+	long-A.out \
+	long-ed.out \
+	long-merge.out \
+	tao-A.out \
+	tao-ed.out \
+	tao-merge.out
 
 .include <bsd.test.mk>
Index: usr.bin/diff3/tests/diff3_test.sh
===================================================================
--- usr.bin/diff3/tests/diff3_test.sh
+++ usr.bin/diff3/tests/diff3_test.sh
@@ -2,6 +2,9 @@
 
 atf_test_case diff3
 atf_test_case diff3_lesssimple
+atf_test_case diff3_ed
+atf_test_case diff3_A
+atf_test_case diff3_merge
 
 diff3_body()
 {
@@ -31,12 +34,6 @@
 
 	atf_check -o file:$(atf_get_srcdir)/7.out \
 		diff3 -i $(atf_get_srcdir)/1.txt $(atf_get_srcdir)/2.txt $(atf_get_srcdir)/3.txt
-
-#	atf_check -o file:$(atf_get_srcdir)/8.out \
-#		diff3 -A -L 1 -L 2 -L 3 $(atf_get_srcdir)/1.txt $(atf_get_srcdir)/2.txt $(atf_get_srcdir)/3.txt
-
-#	atf_check -s exit:1 -o file:$(atf_get_srcdir)/9.out \
-#		diff3 -m -L 1 -L 2 -L 3 $(atf_get_srcdir)/1.txt $(atf_get_srcdir)/2.txt $(atf_get_srcdir)/3.txt
 }
 
 diff3_lesssimple_body()
@@ -45,8 +42,43 @@
 		diff3 -m -L 1 -L 2 -L 3 $(atf_get_srcdir)/4.txt $(atf_get_srcdir)/5.txt $(atf_get_srcdir)/6.txt
 }
 
+diff3_ed_body()
+{
+
+	atf_check -s exit:0 -o file:$(atf_get_srcdir)/tao-ed.out \
+		diff3 -e $(atf_get_srcdir)/lao.txt $(atf_get_srcdir)/tzu.txt $(atf_get_srcdir)/tao.txt
+
+	atf_check -s exit:0 -o file:$(atf_get_srcdir)/long-ed.out \
+		diff3 -e $(atf_get_srcdir)/long-m.txt $(atf_get_srcdir)/long-o.txt $(atf_get_srcdir)/long-y.txt
+}
+
+diff3_A_body()
+{
+	atf_check -s exit:1 -o file:$(atf_get_srcdir)/8.out \
+		diff3 -A -L 1 -L 2 -L 3 $(atf_get_srcdir)/1.txt $(atf_get_srcdir)/2.txt $(atf_get_srcdir)/3.txt
+
+	atf_check -s exit:1 -o file:$(atf_get_srcdir)/tao-A.out \
+		diff3 -A -L lao.txt -L tzu.txt -L tao.txt $(atf_get_srcdir)/lao.txt $(atf_get_srcdir)/tzu.txt $(atf_get_srcdir)/tao.txt
+
+	atf_check -s exit:1 -o file:$(atf_get_srcdir)/long-A.out \
+		diff3 -A -L long-m.txt -L long-o.txt -L long-y.txt $(atf_get_srcdir)/long-m.txt $(atf_get_srcdir)/long-o.txt $(atf_get_srcdir)/long-y.txt
+}
+
+diff3_merge_body()
+{
+	atf_check -s exit:1 -o file:$(atf_get_srcdir)/9.out \
+		diff3 -m -L 1 -L 2 -L 3 $(atf_get_srcdir)/1.txt $(atf_get_srcdir)/2.txt $(atf_get_srcdir)/3.txt
+	atf_check -s exit:1 -o file:$(atf_get_srcdir)/tao-merge.out \
+		diff3 -m -L lao.txt -L tzu.txt -L tao.txt $(atf_get_srcdir)/lao.txt $(atf_get_srcdir)/tzu.txt $(atf_get_srcdir)/tao.txt
+	atf_check -s exit:1 -o file:$(atf_get_srcdir)/long-merge.out \
+		diff3 -m -L long-m.txt -L long-o.txt -L long-y.txt $(atf_get_srcdir)/long-m.txt $(atf_get_srcdir)/long-o.txt $(atf_get_srcdir)/long-y.txt
+}
+
 atf_init_test_cases()
 {
 	atf_add_test_case diff3
 #	atf_add_test_case diff3_lesssimple
+	atf_add_test_case diff3_ed
+	atf_add_test_case diff3_A
+	atf_add_test_case diff3_merge
 }
Index: usr.bin/diff3/tests/lao.txt
===================================================================
--- /dev/null
+++ usr.bin/diff3/tests/lao.txt
@@ -0,0 +1,11 @@
+The Way that can be told of is not the eternal Way;
+The name that can be named is not the eternal name.
+The Nameless is the origin of Heaven and Earth;
+The Named is the mother of all things.
+Therefore let there always be non-being,
+  so we may see their subtlety,
+And let there always be being,
+  so we may see their outcome.
+The two are the same,
+But after they are produced,
+  they have different names.
Index: usr.bin/diff3/tests/long-A.out
===================================================================
--- /dev/null
+++ usr.bin/diff3/tests/long-A.out
@@ -0,0 +1,22 @@
+24d
+16a
+||||||| long-o.txt
+This line is different in yours and mine, but the different in each
+=======
+This line is different in yours and mine, but the best in yours
+>>>>>>> long-y.txt
+.
+15a
+<<<<<<< long-m.txt
+.
+11a
+>>>>>>> long-y.txt
+.
+10a
+<<<<<<< long-o.txt
+This line is different in yours and mine, but the same
+=======
+.
+8c
+This line is different in yours, much butter
+.
Index: usr.bin/diff3/tests/long-ed.out
===================================================================
--- /dev/null
+++ usr.bin/diff3/tests/long-ed.out
@@ -0,0 +1,7 @@
+24d
+16c
+This line is different in yours and mine, but the best in yours
+.
+8c
+This line is different in yours, much butter
+.
Index: usr.bin/diff3/tests/long-m.txt
===================================================================
--- /dev/null
+++ usr.bin/diff3/tests/long-m.txt
@@ -0,0 +1,26 @@
+This is a long file
+These lines are the same in all three files
+These lines are the same in all three files
+This line is different in mine, not better
+These lines are the same in all three files
+These lines are the same in all three files
+These lines are the same in all three files
+This line is different in yours
+These lines are the same in all three files
+These lines are the same in all three files
+This line is different in yours and mine, the same is in both
+These lines are the same in all three files
+These lines are the same in all three files
+These lines are the same in all three files
+These lines are the same in all three files
+This line is different in yours and mine, best change in mine
+These lines are the same in all three files
+These lines are the same in all three files
+These lines are the same in all three files
+These lines are the same in all three files
+These lines are the same in all three files
+These lines are the same in all three files
+These lines are the same in all three files
+This line is deleted in yours
+These lines are the same in all three files
+These lines are the same in all three files
Index: usr.bin/diff3/tests/long-merge.out
===================================================================
--- /dev/null
+++ usr.bin/diff3/tests/long-merge.out
@@ -0,0 +1,35 @@
+This is a long file
+These lines are the same in all three files
+These lines are the same in all three files
+This line is different in mine, not better
+These lines are the same in all three files
+These lines are the same in all three files
+These lines are the same in all three files
+This line is different in yours, much butter
+These lines are the same in all three files
+These lines are the same in all three files
+<<<<<<< long-o.txt
+This line is different in yours and mine, but the same
+=======
+This line is different in yours and mine, the same is in both
+>>>>>>> long-y.txt
+These lines are the same in all three files
+These lines are the same in all three files
+These lines are the same in all three files
+These lines are the same in all three files
+<<<<<<< long-m.txt
+This line is different in yours and mine, best change in mine
+||||||| long-o.txt
+This line is different in yours and mine, but the different in each
+=======
+This line is different in yours and mine, but the best in yours
+>>>>>>> long-y.txt
+These lines are the same in all three files
+These lines are the same in all three files
+These lines are the same in all three files
+These lines are the same in all three files
+These lines are the same in all three files
+These lines are the same in all three files
+These lines are the same in all three files
+These lines are the same in all three files
+These lines are the same in all three files
Index: usr.bin/diff3/tests/long-o.txt
===================================================================
--- /dev/null
+++ usr.bin/diff3/tests/long-o.txt
@@ -0,0 +1,27 @@
+This is a long file
+These lines are the same in all three files
+These lines are the same in all three files
+This line is different in mine
+These lines are the same in all three files
+These lines are the same in all three files
+These lines are the same in all three files
+This line is different in yours
+These lines are the same in all three files
+These lines are the same in all three files
+This line is different in yours and mine, but the same
+These lines are the same in all three files
+These lines are the same in all three files
+These lines are the same in all three files
+These lines are the same in all three files
+This line is different in yours and mine, but the different in each
+These lines are the same in all three files
+These lines are the same in all three files
+These lines are the same in all three files
+These lines are the same in all three files
+This line is deleted in mine
+These lines are the same in all three files
+These lines are the same in all three files
+These lines are the same in all three files
+This line is deleted in yours
+These lines are the same in all three files
+These lines are the same in all three files
Index: usr.bin/diff3/tests/long-y.txt
===================================================================
--- /dev/null
+++ usr.bin/diff3/tests/long-y.txt
@@ -0,0 +1,26 @@
+This is a long file
+These lines are the same in all three files
+These lines are the same in all three files
+This line is different in mine
+These lines are the same in all three files
+These lines are the same in all three files
+These lines are the same in all three files
+This line is different in yours, much butter
+These lines are the same in all three files
+These lines are the same in all three files
+This line is different in yours and mine, the same is in both
+These lines are the same in all three files
+These lines are the same in all three files
+These lines are the same in all three files
+These lines are the same in all three files
+This line is different in yours and mine, but the best in yours
+These lines are the same in all three files
+These lines are the same in all three files
+These lines are the same in all three files
+These lines are the same in all three files
+This line is deleted in mine
+These lines are the same in all three files
+These lines are the same in all three files
+These lines are the same in all three files
+These lines are the same in all three files
+These lines are the same in all three files
Index: usr.bin/diff3/tests/tao-A.out
===================================================================
--- /dev/null
+++ usr.bin/diff3/tests/tao-A.out
@@ -0,0 +1,23 @@
+11a
+||||||| tzu.txt
+They both may be called deep and profound.
+Deeper and more profound,
+The door of all subtleties!
+=======
+
+  -- The Way of Lao-Tzu, tr. Wing-tsit Chan
+>>>>>>> tao.txt
+.
+11a
+<<<<<<< lao.txt
+.
+8c
+  so we may see their result.
+.
+2a
+>>>>>>> tao.txt
+.
+0a
+<<<<<<< tzu.txt
+=======
+.
Index: usr.bin/diff3/tests/tao-ed.out
===================================================================
--- /dev/null
+++ usr.bin/diff3/tests/tao-ed.out
@@ -0,0 +1,7 @@
+11a
+
+  -- The Way of Lao-Tzu, tr. Wing-tsit Chan
+.
+8c
+  so we may see their result.
+.
Index: usr.bin/diff3/tests/tao-merge.out
===================================================================
--- /dev/null
+++ usr.bin/diff3/tests/tao-merge.out
@@ -0,0 +1,23 @@
+<<<<<<< tzu.txt
+=======
+The Way that can be told of is not the eternal Way;
+The name that can be named is not the eternal name.
+>>>>>>> tao.txt
+The Nameless is the origin of Heaven and Earth;
+The Named is the mother of all things.
+Therefore let there always be non-being,
+  so we may see their subtlety,
+And let there always be being,
+  so we may see their result.
+The two are the same,
+But after they are produced,
+  they have different names.
+<<<<<<< lao.txt
+||||||| tzu.txt
+They both may be called deep and profound.
+Deeper and more profound,
+The door of all subtleties!
+=======
+
+  -- The Way of Lao-Tzu, tr. Wing-tsit Chan
+>>>>>>> tao.txt
Index: usr.bin/diff3/tests/tao.txt
===================================================================
--- /dev/null
+++ usr.bin/diff3/tests/tao.txt
@@ -0,0 +1,14 @@
+The Way that can be told of is not the eternal Way;
+The name that can be named is not the eternal name.
+The Nameless is the origin of Heaven and Earth;
+The named is the mother of all things.
+
+Therefore let there always be non-being,
+  so we may see their subtlety,
+And let there always be being,
+  so we may see their result.
+The two are the same,
+But after they are produced,
+  they have different names.
+
+  -- The Way of Lao-Tzu, tr. Wing-tsit Chan
Index: usr.bin/diff3/tests/tzu.txt
===================================================================
--- /dev/null
+++ usr.bin/diff3/tests/tzu.txt
@@ -0,0 +1,13 @@
+The Nameless is the origin of Heaven and Earth;
+The named is the mother of all things.
+
+Therefore let there always be non-being,
+  so we may see their subtlety,
+And let there always be being,
+  so we may see their outcome.
+The two are the same,
+But after they are produced,
+  they have different names.
+They both may be called deep and profound.
+Deeper and more profound,
+The door of all subtleties!