diff --git a/src/testdir/test_increment.vim b/src/testdir/test_increment.vim
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+" Tests for using Ctrl-A/Ctrl-X on visual selections
+
+func SetUp()
+  new dummy
+  set nrformats&vim
+endfunc
+
+func TearDown()
+  bwipe!
+endfunc
+
+" 1) Ctrl-A on visually selected number
+" Text:
+" foobar-10
+"     Expected:
+"     1)    Ctrl-A on start of line:
+"     foobar-9
+"     2)    Ctrl-A on visually selected "-10":
+"     foobar-9
+"     3)    Ctrl-A on visually selected "10":
+"     foobar-11
+"     4)    Ctrl-X on visually selected "-10"
+"     foobar-11
+"     5)    Ctrl-X on visually selected "10"
+"     foobar-9
+func Test_visual_increment_01()
+  call setline(1, repeat(["foobaar-10"], 5))
+
+  call cursor(1, 1)
+  exec "norm! \<C-A>"
+  call assert_equal("foobaar-9", getline('.'))
+  call assert_equal([0, 1, 9, 0], getpos('.'))
+
+  call cursor(2, 1)
+  exec "norm! f-v$\<C-A>"
+  call assert_equal("foobaar-9", getline('.'))
+  call assert_equal([0, 2, 8, 0], getpos('.'))
+
+  call cursor(3, 1)
+  exec "norm! f1v$\<C-A>"
+  call assert_equal("foobaar-11", getline('.'))
+  call assert_equal([0, 3, 9, 0], getpos('.'))
+
+  call cursor(4, 1)
+  exec "norm! f-v$\<C-X>"
+  call assert_equal("foobaar-11", getline('.'))
+  call assert_equal([0, 4, 8, 0], getpos('.'))
+
+  call cursor(5, 1)
+  exec "norm! f1v$\<C-X>"
+  call assert_equal("foobaar-9", getline('.'))
+  call assert_equal([0, 5, 9, 0], getpos('.'))
+endfunc
+
+" 2) Ctrl-A on visually selected lines
+" Text:
+" 10
+" 20
+" 30
+" 40
+"
+"     Expected:
+"     1) Ctrl-A on visually selected lines:
+" 11
+" 21
+" 31
+" 41
+"
+"     2) Ctrl-X on visually selected lines:
+" 9
+" 19
+" 29
+" 39
+func Test_visual_increment_02()
+  call setline(1, ["10", "20", "30", "40"])
+  exec "norm! GV3k$\<C-A>"
+  call assert_equal(["11", "21", "31", "41"], getline(1, '$'))
+  call assert_equal([0, 1, 1, 0], getpos('.'))
+
+  call setline(1, ["10", "20", "30", "40"])
+  exec "norm! GV3k$\<C-X>"
+  call assert_equal(["9", "19", "29", "39"], getline(1, '$'))
+  call assert_equal([0, 1, 1, 0], getpos('.'))
+endfunc
+
+" 3) g Ctrl-A on visually selected lines, with non-numbers in between
+" Text:
+" 10
+"
+" 20
+"
+" 30
+"
+" 40
+"
+"     Expected:
+"     1) 2 g Ctrl-A on visually selected lines:
+" 12
+"
+" 24
+"
+" 36
+"
+" 48
+"     2) 2 g Ctrl-X on visually selected lines
+" 8
+"
+" 16
+"
+" 24
+"
+" 32
+func Test_visual_increment_03()
+  call setline(1, ["10", "", "20", "", "30", "", "40"])
+  exec "norm! GV6k2g\<C-A>"
+  call assert_equal(["12", "", "24", "", "36", "", "48"], getline(1, '$'))
+  call assert_equal([0, 1, 1, 0], getpos('.'))
+
+  call setline(1, ["10", "", "20", "", "30", "", "40"])
+  exec "norm! GV6k2g\<C-X>"
+  call assert_equal(["8", "", "16", "", "24", "", "32"], getline(1, '$'))
+  call assert_equal([0, 1, 1, 0], getpos('.'))
+endfunc
+
+" 4) Ctrl-A on non-number
+" Text:
+" foobar-10
+"     Expected:
+"     1) visually select foobar:
+"     foobar-10
+func Test_visual_increment_04()
+  call setline(1, ["foobar-10"])
+  exec "norm! vf-\<C-A>"
+  call assert_equal(["foobar-10"], getline(1, '$'))
+  " NOTE: I think this is correct behavior...
+  "call assert_equal([0, 1, 1, 0], getpos('.'))
+endfunc
+
+" 5) g<Ctrl-A> on letter
+" Test:
+" a
+" a
+" a
+" a
+"     Expected:
+"     1) g Ctrl-A on visually selected lines
+"     b
+"     c
+"     d
+"     e
+func Test_visual_increment_05()
+  set nrformats+=alpha
+  call setline(1, repeat(["a"], 4))
+  exec "norm! GV3kg\<C-A>"
+  call assert_equal(["b", "c", "d", "e"], getline(1, '$'))
+  call assert_equal([0, 1, 1, 0], getpos('.'))
+endfunc
+
+" 6) g<Ctrl-A> on letter
+" Test:
+" z
+" z
+" z
+" z
+"     Expected:
+"     1) g Ctrl-X on visually selected lines
+"     y
+"     x
+"     w
+"     v
+func Test_visual_increment_06()
+  set nrformats+=alpha
+  call setline(1, repeat(["z"], 4))
+  exec "norm! GV3kg\<C-X>"
+  call assert_equal(["y", "x", "w", "v"], getline(1, '$'))
+  call assert_equal([0, 1, 1, 0], getpos('.'))
+endfunc
+
+" 7) <Ctrl-A> on letter
+" Test:
+" 2
+" 1
+" 0
+" -1
+" -2
+"
+"     Expected:
+"     1) Ctrl-A on visually selected lines
+"     3
+"     2
+"     1
+"     0
+"     -1
+"
+"     2) Ctrl-X on visually selected lines
+"     1
+"     0
+"     -1
+"     -2
+"     -3
+func Test_visual_increment_07()
+  call setline(1, ["2", "1", "0", "-1", "-2"])
+  exec "norm! GV4k\<C-A>"
+  call assert_equal(["3", "2", "1", "0", "-1"], getline(1, '$'))
+  call assert_equal([0, 1, 1, 0], getpos('.'))
+
+  call setline(1, ["2", "1", "0", "-1", "-2"])
+  exec "norm! GV4k\<C-X>"
+  call assert_equal(["1", "0", "-1", "-2", "-3"], getline(1, '$'))
+  call assert_equal([0, 1, 1, 0], getpos('.'))
+endfunc
+
+" 8) Block increment on 0x9
+" Text:
+" 0x9
+" 0x9
+"     Expected:
+"     1) Ctrl-A on visually block selected region (cursor at beginning):
+"     0xa
+"     0xa
+"     2) Ctrl-A on visually block selected region (cursor at end)
+"     0xa
+"     0xa
+func Test_visual_increment_08()
+  call setline(1, repeat(["0x9"], 2))
+  exec "norm! \<C-V>j$\<C-A>"
+  call assert_equal(["0xa", "0xa"], getline(1, '$'))
+  call assert_equal([0, 1, 1, 0], getpos('.'))
+
+  call setline(1, repeat(["0x9"], 2))
+  exec "norm! gg$\<C-V>+\<C-A>"
+  call assert_equal(["0xa", "0xa"], getline(1, '$'))
+  call assert_equal([0, 1, 1, 0], getpos('.'))
+endfunc
+
+" 9) Increment and redo
+" Text:
+" 2
+" 2
+"
+" 3
+" 3
+"
+"     Expected:
+"     1) 2 Ctrl-A on first 2 visually selected lines
+"     4
+"     4
+"     2) redo (.) on 3
+"     5
+"     5
+func Test_visual_increment_09()
+  call setline(1, ["2", "2", "", "3", "3", ""])
+  exec "norm! ggVj2\<C-A>"
+  call assert_equal(["4", "4", "", "3", "3", ""], getline(1, '$'))
+  call assert_equal([0, 1, 1, 0], getpos('.'))
+
+  exec "norm! 3j."
+  call assert_equal(["4", "4", "", "5", "5", ""], getline(1, '$'))
+  call assert_equal([0, 4, 1, 0], getpos('.'))
+endfunc
+
+" 10) sequentially decrement 1
+" Text:
+" 1
+" 1
+" 1
+" 1
+"     Expected:
+"     1) g Ctrl-X on visually selected lines
+"     0
+"     -1
+"     -2
+"     -3
+func Test_visual_increment_10()
+  call setline(1, repeat(["1"], 4))
+  exec "norm! GV3kg\<C-X>"
+  call assert_equal(["0", "-1", "-2", "-3"], getline(1, '$'))
+  call assert_equal([0, 1, 1, 0], getpos('.'))
+endfunc
+
+" 11) visually block selected indented lines
+" Text:
+"     1
+" 1
+"     1
+"     1
+"     Expexted:
+"     1) g Ctrl-A on block selected indented lines
+"     2
+" 1
+"     3
+"     4
+func Test_visual_increment_11()
+  call setline(1, ["    1", "1", "    1", "    1"])
+  exec "norm! f1\<C-V>3jg\<C-A>"
+  call assert_equal(["    2", "1", "    3", "    4"], getline(1, '$'))
+  call assert_equal([0, 1, 5, 0], getpos('.'))
+endfunc
+
+" 12) visually selected several columns
+" Text:
+" 0 0
+" 0 0
+" 0 0
+"     Expected:
+"     1) 'v' select last zero and first zeroes
+"     0 1
+"     1 0
+"     1 0
+func Test_visual_increment_12()
+  call setline(1, repeat(["0 0"], 3))
+  exec "norm! $v++\<C-A>"
+  call assert_equal(["0 1", "1 0", "1 0"], getline(1, '$'))
+  call assert_equal([0, 1, 3, 0], getpos('.'))
+endfunc
+
+" 13) visually selected part of columns
+" Text:
+" max: 100px
+" max: 200px
+" max: 300px
+" max: 400px
+"     Expected:
+"     1) 'v' on first two numbers Ctrl-A
+"     max: 110px
+"     max: 220px
+"     max: 330px
+"     max: 400px
+"     2) 'v' on first two numbers Ctrl-X
+"     max: 90px
+"     max: 190px
+"     max: 290px
+"     max: 400px
+func Test_visual_increment_13()
+  call setline(1, ["max: 100px", "max: 200px", "max: 300px", "max: 400px"])
+  exec "norm! f1\<C-V>l2j\<C-A>"
+  call assert_equal(["max: 110px", "max: 210px", "max: 310px", "max: 400px"], getline(1, '$'))
+  call assert_equal([0, 1, 6, 0], getpos('.'))
+
+  call setline(1, ["max: 100px", "max: 200px", "max: 300px", "max: 400px"])
+  exec "norm! ggf1\<C-V>l2j\<C-X>"
+  call assert_equal(["max: 90px", "max: 190px", "max: 290px", "max: 400px"], getline(1, '$'))
+  call assert_equal([0, 1, 6, 0], getpos('.'))
+endfunc
+
+" 14) redo in block mode
+" Text:
+" 1 1
+" 1 1
+"     Expected:
+"     1) Ctrl-a on first column, redo on second column
+"     2 2
+"     2 2
+func Test_visual_increment_14()
+  call setline(1, repeat(["1 1"], 2))
+  exec "norm! G\<C-V>k\<C-A>w."
+  call assert_equal(["2 2", "2 2"], getline(1, '$'))
+  call assert_equal([0, 1, 3, 0], getpos('.'))
+endfunc
+
+" 15) block select single numbers
+" Text:
+" 101
+"     Expected:
+"     1) Ctrl-a on visually selected zero
+"     111
+func Test_visual_increment_15()
+  call setline(1, ["101"])
+  exec "norm! lv\<C-A>"
+  call assert_equal(["111"], getline(1, '$'))
+  call assert_equal([0, 1, 2, 0], getpos('.'))
+endfunc
+
+" 16) increment right aligned numbers
+" Text:
+"    1
+"   19
+"  119
+"     Expected:
+"     1) Ctrl-a on line selected region
+"        2
+"       20
+"      120
+func Test_visual_increment_16()
+  call setline(1, ["   1", "  19", " 119"])
+  exec "norm! VG\<C-A>"
+  call assert_equal(["   2", "  20", " 120"], getline(1, '$'))
+  call assert_equal([0, 1, 1, 0], getpos('.'))
+endfunc
+
+" 17) block-wise increment and redo
+" Text:
+"   100
+"   1
+"
+"   100
+"   1
+"
+"   Expected:
+"   1) Ctrl-V j $ on first block, afterwards '.' on second
+"   101
+"   2
+"
+"   101
+"   2
+func Test_visual_increment_17()
+  call setline(1, [" 100", " 1", "", " 100", " 1"])
+  exec "norm! \<C-V>j$\<C-A>2j."
+  call assert_equal([" 101", " 2", "", " 101", " 1"], getline(1, '$'))
+  call assert_equal([0, 3, 1, 0], getpos('.'))
+endfunc
+
+" 18) repeat of g<Ctrl-a>
+" Text:
+"   0
+"   0
+"   0
+"   0
+"
+"   Expected:
+"   1) V 4j g<ctrl-a>, repeat twice afterwards with .
+"   3
+"   6
+"   9
+"   12
+func Test_visual_increment_18()
+  call setline(1, repeat(["0"], 4))
+  exec "norm! GV3kg\<C-A>"
+  exec "norm! .."
+  call assert_equal(["3", "6", "9", "12"], getline(1, '$'))
+  call assert_equal([0, 1, 1, 0], getpos('.'))
+endfunc
+
+" 19) increment on number with nrformat including alpha
+" Text:
+"  1
+"  1a
+"
+"  Expected:
+"  1) <Ctrl-V>j$ <ctrl-a>
+"  2
+"  2a
+func Test_visual_increment_19()
+  set nrformats+=alpha
+  call setline(1, ["1", "1a"])
+  exec "norm! \<C-V>G$\<C-A>"
+  call assert_equal(["2", "2a"], getline(1, '$'))
+  call assert_equal([0, 1, 1, 0], getpos('.'))
+endfunc
+
+" 20) increment a single letter
+" Text:
+"  a
+"
+"  Expected:
+"  1) <Ctrl-a> and cursor is on a
+"  b
+func Test_visual_increment_20()
+  set nrformats+=alpha
+  call setline(1, ["a"])
+  exec "norm! \<C-A>"
+  call assert_equal(["b"], getline(1, '$'))
+  call assert_equal([0, 1, 1, 0], getpos('.'))
+endfunc
+
+" 21) block-wise increment on part of hexadecimal
+" Text:
+" 0x123456
+"
+"   Expected:
+"   1) Ctrl-V f3 <ctrl-a>
+" 0x124456
+func Test_visual_increment_21()
+  call setline(1, ["0x123456"])
+  exec "norm! \<C-V>f3\<C-A>"
+  call assert_equal(["0x124456"], getline(1, '$'))
+  call assert_equal([0, 1, 1, 0], getpos('.'))
+endfunc
+
+" 22) Block increment on 0b0
+" Text:
+" 0b1
+" 0b1
+"     Expected:
+"     1) Ctrl-A on visually block selected region (cursor at beginning):
+"     0b10
+"     0b10
+"     2) Ctrl-A on visually block selected region (cursor at end)
+"     0b10
+"     0b10
+func Test_visual_increment_22()
+  call setline(1, repeat(["0b1"], 2))
+  exec "norm! \<C-V>j$\<C-A>"
+  call assert_equal(repeat(["0b10"], 2), getline(1, '$'))
+  call assert_equal([0, 1, 1, 0], getpos('.'))
+
+  call setline(1, repeat(["0b1"], 2))
+  exec "norm! $\<C-V>+\<C-A>"
+  call assert_equal(repeat(["0b10"], 2), getline(1, '$'))
+  call assert_equal([0, 1, 1, 0], getpos('.'))
+endfunc
+
+" 23) block-wise increment on part of binary
+" Text:
+" 0b1001
+"
+"   Expected:
+"   1) Ctrl-V 5l <ctrl-a>
+" 0b1011
+func Test_visual_increment_23()
+  call setline(1, ["0b1001"])
+  exec "norm! \<C-V>4l\<C-A>"
+  call assert_equal(["0b1011"], getline(1, '$'))
+  call assert_equal([0, 1, 1, 0], getpos('.'))
+endfunc
+
+" 24) increment hexadecimal
+" Text:
+" 0x0b1001
+"
+"   Expected:
+"   1) <ctrl-a>
+" 0x0b1002
+func Test_visual_increment_24()
+  call setline(1, ["0x0b1001"])
+  exec "norm! \<C-V>$\<C-A>"
+  call assert_equal(["0x0b1002"], getline(1, '$'))
+  call assert_equal([0, 1, 1, 0], getpos('.'))
+endfunc
+
+" 25) increment binary with nrformats including alpha
+" Text:
+" 0b1001a
+"
+"   Expected:
+"   1) <ctrl-a>
+" 0b1010a
+func Test_visual_increment_25()
+  set nrformats+=alpha
+  call setline(1, ["0b1001a"])
+  exec "norm! \<C-V>$\<C-A>"
+  call assert_equal(["0b1010a"], getline(1, '$'))
+  call assert_equal([0, 1, 1, 0], getpos('.'))
+endfunc
+
+" 26) increment binary with 32 bits
+" Text:
+" 0b11111111111111111111111111111110
+"
+"   Expected:
+"   1) <ctrl-a>
+" 0b11111111111111111111111111111111
+func Test_visual_increment_26()
+  set nrformats+=alpha
+  call setline(1, ["0b11111111111111111111111111111110"])
+  exec "norm! \<C-V>$\<C-A>"
+  call assert_equal(["0b11111111111111111111111111111111"], getline(1, '$'))
+  call assert_equal([0, 1, 1, 0], getpos('.'))
+endfunc
+
+" vim: tabstop=2 shiftwidth=2 expandtab