#!/bin/sh

setglobal test_description = ''common tail optimization''

source ./test-lib.sh

setglobal z = 'zzzzzzzz' ;# 8
setglobal z = ""$z$z$z$z$z$z$z$z"" ;# 64
setglobal z = ""$z$z$z$z$z$z$z$z"" ;# 512
setglobal z = ""$z$z$z$z"" ;# 2048
setglobal z2047 = $[expr $z : '.\(.*\)] ; #2047

setglobal x = 'zzzzzzzzzz'			;# 10
setglobal y = ""$x$x$x$x$x$x$x$x$x$x""	;# 100
setglobal z = ""$y$y$y$y$y$y$y$y$y$y""	;# 1000
setglobal z1000 = $z
setglobal z100 = $y
setglobal z10 = $x

proc zs {
	setglobal count = $1
	while test "$count" -ge 1000
	{
		setglobal count = $shExpr('$count - 1000')
		printf "%s" $z1000
	}
	while test "$count" -ge 100
	{
		setglobal count = $shExpr('$count - 100')
		printf "%s" $z100
	}
	while test "$count" -ge 10
	{
		setglobal count = $shExpr('$count - 10')
		printf "%s" $z10
	}
	while test "$count" -ge 1
	{
		setglobal count = $shExpr('$count - 1')
		printf "z"
	}
}

proc zc {
	sed -e "/^index/d" \
		-e "s/$z1000/Q/g" \
		-e "s/QQQQQQQQQ/Z9000/g" \
		-e "s/QQQQQQQQ/Z8000/g" \
		-e "s/QQQQQQQ/Z7000/g" \
		-e "s/QQQQQQ/Z6000/g" \
		-e "s/QQQQQ/Z5000/g" \
		-e "s/QQQQ/Z4000/g" \
		-e "s/QQQ/Z3000/g" \
		-e "s/QQ/Z2000/g" \
		-e "s/Q/Z1000/g" \
		-e "s/$z100/Q/g" \
		-e "s/QQQQQQQQQ/Z900/g" \
		-e "s/QQQQQQQQ/Z800/g" \
		-e "s/QQQQQQQ/Z700/g" \
		-e "s/QQQQQQ/Z600/g" \
		-e "s/QQQQQ/Z500/g" \
		-e "s/QQQQ/Z400/g" \
		-e "s/QQQ/Z300/g" \
		-e "s/QQ/Z200/g" \
		-e "s/Q/Z100/g" \
		-e "s/000Z//g" \
		-e "s/$z10/Q/g" \
		-e "s/QQQQQQQQQ/Z90/g" \
		-e "s/QQQQQQQQ/Z80/g" \
		-e "s/QQQQQQQ/Z70/g" \
		-e "s/QQQQQQ/Z60/g" \
		-e "s/QQQQQ/Z50/g" \
		-e "s/QQQQ/Z40/g" \
		-e "s/QQQ/Z30/g" \
		-e "s/QQ/Z20/g" \
		-e "s/Q/Z10/g" \
		-e "s/00Z//g" \
		-e "s/z/Q/g" \
		-e "s/QQQQQQQQQ/Z9/g" \
		-e "s/QQQQQQQQ/Z8/g" \
		-e "s/QQQQQQQ/Z7/g" \
		-e "s/QQQQQQ/Z6/g" \
		-e "s/QQQQQ/Z5/g" \
		-e "s/QQQQ/Z4/g" \
		-e "s/QQQ/Z3/g" \
		-e "s/QQ/Z2/g" \
		-e "s/Q/Z1/g" \
		-e "s/0Z//g" \
	;
}

proc expect_pattern {
	setglobal cnt = $1
	cat << """
diff --git a/file-a$cnt b/file-a$cnt
--- a/file-a$cnt
+++ b/file-a$cnt
@@ -1 +1 @@
-Z$(cnt)a
+Z$(cnt)A
diff --git a/file-b$cnt b/file-b$cnt
--- a/file-b$cnt
+++ b/file-b$cnt
@@ -1 +1 @@
-b
+B
diff --git a/file-c$cnt b/file-c$cnt
--- a/file-c$cnt
+++ b/file-c$cnt
@@ -1 +1 @@
-cZ$cnt
\ No newline at end of file
+CZ$cnt
\ No newline at end of file
diff --git a/file-d$cnt b/file-d$cnt
--- a/file-d$cnt
+++ b/file-d$cnt
@@ -1 +1 @@
-d
+D
"""
}

setglobal sample = ''1023 1024 1025 2047 4095''

test_expect_success setup '

	for n in $sample
	do
		( zs $n ; echo a ) >file-a$n &&
		( echo b; zs $n; echo ) >file-b$n &&
		( printf c; zs $n ) >file-c$n &&
		( echo d; zs $n ) >file-d$n &&

		git add file-a$n file-b$n file-c$n file-d$n &&

		( zs $n ; echo A ) >file-a$n &&
		( echo B; zs $n; echo ) >file-b$n &&
		( printf C; zs $n ) >file-c$n &&
		( echo D; zs $n ) >file-d$n &&

		expect_pattern $n || return 1

	done >expect
'

test_expect_success 'diff -U0' '

	for n in $sample
	do
		git diff -U0 file-?$n
	done | zc >actual &&
	test_cmp expect actual

'

test_done