new file mode 100644
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+++ b/src/testdir/test_cdo.vim
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+" Tests for the :cdo, :cfdo, :ldo and :lfdo commands
+
+lang mess C
+if !has('quickfix')
+  finish
+endif
+
+" Create the files used by the tests
+function SetUp()
+  call writefile(["Line1", "Line2", "Line3"], 'Xtestfile1')
+  call writefile(["Line1", "Line2", "Line3"], 'Xtestfile2')
+  call writefile(["Line1", "Line2", "Line3"], 'Xtestfile3')
+endfunction
+
+" Remove the files used by the tests
+function TearDown()
+  call delete('Xtestfile1')
+  call delete('Xtestfile2')
+  call delete('Xtestfile3')
+endfunction
+
+" Returns the current line in '<filename> <linenum>L <column>C' format
+function GetRuler()
+  return expand('%') . ' ' . line('.') . 'L' . ' ' . col('.') . 'C'
+endfunction
+
+" Tests for the :cdo and :ldo commands
+function XdoTests(cchar)
+  enew
+
+  " Shortcuts for calling the cdo and ldo commands
+  let Xdo = a:cchar . 'do'
+  let Xgetexpr = a:cchar . 'getexpr'
+  let Xprev = a:cchar. 'prev'
+  let XdoCmd = Xdo . ' call add(l, GetRuler())'
+
+  " Try with an empty list
+  let l = []
+  exe XdoCmd
+  call assert_equal([], l)
+
+  " Populate the list and then try
+  exe Xgetexpr . " ['non-error 1', 'Xtestfile1:1:3:Line1', 'non-error 2', 'Xtestfile2:2:2:Line2', 'non-error 3', 'Xtestfile3:3:1:Line3']"
+
+  let l = []
+  exe XdoCmd
+  call assert_equal(['Xtestfile1 1L 3C', 'Xtestfile2 2L 2C', 'Xtestfile3 3L 1C'], l)
+
+  " Run command only on selected error lines
+  let l = []
+  enew
+  exe "2,3" . XdoCmd
+  call assert_equal(['Xtestfile2 2L 2C', 'Xtestfile3 3L 1C'], l)
+
+  " Boundary condition tests
+  let l = []
+  enew
+  exe "1,1" . XdoCmd
+  call assert_equal(['Xtestfile1 1L 3C'], l)
+
+  let l = []
+  enew
+  exe "3" . XdoCmd
+  call assert_equal(['Xtestfile3 3L 1C'], l)
+
+  " Range test commands
+  let l = []
+  enew
+  exe "%" . XdoCmd
+  call assert_equal(['Xtestfile1 1L 3C', 'Xtestfile2 2L 2C', 'Xtestfile3 3L 1C'], l)
+
+  let l = []
+  enew
+  exe "1,$" . XdoCmd
+  call assert_equal(['Xtestfile1 1L 3C', 'Xtestfile2 2L 2C', 'Xtestfile3 3L 1C'], l)
+
+  let l = []
+  enew
+  exe Xprev
+  exe "." . XdoCmd
+  call assert_equal(['Xtestfile2 2L 2C'], l)
+
+  let l = []
+  enew
+  exe "+" . XdoCmd
+  call assert_equal(['Xtestfile3 3L 1C'], l)
+
+  " Invalid error lines test
+  let l = []
+  enew
+  exe "silent! 27" . XdoCmd
+  exe "silent! 4,5" . XdoCmd
+  call assert_equal([], l)
+
+  " Run commands from an unsaved buffer
+  let v:errmsg=''
+  let l = []
+  enew
+  setlocal modified
+  exe "silent! 2,2" . XdoCmd
+  if v:errmsg !~# 'No write since last change'
+    call add(v:errors, 'Unsaved file change test failed')
+  endif
+
+  " If the executed command fails, then the operation should be aborted
+  enew!
+  let subst_count = 0
+  exe "silent!" . Xdo . " s/Line/xLine/ | let subst_count += 1"
+  if subst_count != 1 || getline('.') != 'xLine1'
+    call add(v:errors, 'Abort command on error test failed')
+  endif
+
+  let l = []
+  exe "2,2" . Xdo . "! call add(l, GetRuler())"
+  call assert_equal(['Xtestfile2 2L 2C'], l)
+
+  " List with no valid error entries
+  let l = []
+  edit! +2 Xtestfile1
+  exe Xgetexpr . " ['non-error 1', 'non-error 2', 'non-error 3']"
+  exe XdoCmd
+  call assert_equal([], l)
+  exe "silent! 2" . XdoCmd
+  call assert_equal([], l)
+  let v:errmsg=''
+  exe "%" . XdoCmd
+  exe "1,$" . XdoCmd
+  exe "." . XdoCmd
+  call assert_equal('', v:errmsg)
+
+  " List with only one valid entry
+  let l = []
+  exe Xgetexpr . " ['Xtestfile3:3:1:Line3']"
+  exe XdoCmd
+  call assert_equal(['Xtestfile3 3L 1C'], l)
+
+endfunction
+
+" Tests for the :cfdo and :lfdo commands
+function XfdoTests(cchar)
+  enew
+
+  " Shortcuts for calling the cfdo and lfdo commands
+  let Xfdo = a:cchar . 'fdo'
+  let Xgetexpr = a:cchar . 'getexpr'
+  let XfdoCmd = Xfdo . ' call add(l, GetRuler())'
+  let Xpfile = a:cchar. 'pfile'
+
+  " Clear the quickfix/location list
+  exe Xgetexpr . " []"
+
+  " Try with an empty list
+  let l = []
+  exe XfdoCmd
+  call assert_equal([], l)
+
+  " Populate the list and then try
+  exe Xgetexpr . " ['non-error 1', 'Xtestfile1:1:3:Line1', 'Xtestfile1:2:1:Line2', 'non-error 2', 'Xtestfile2:2:2:Line2', 'non-error 3', 'Xtestfile3:2:3:Line2', 'Xtestfile3:3:1:Line3']"
+
+  let l = []
+  exe XfdoCmd
+  call assert_equal(['Xtestfile1 1L 3C', 'Xtestfile2 2L 2C', 'Xtestfile3 2L 3C'], l)
+
+  " Run command only on selected error lines
+  let l = []
+  exe "2,3" . XfdoCmd
+  call assert_equal(['Xtestfile2 2L 2C', 'Xtestfile3 2L 3C'], l)
+
+  " Boundary condition tests
+  let l = []
+  exe "3" . XfdoCmd
+  call assert_equal(['Xtestfile3 2L 3C'], l)
+
+  " Range test commands
+  let l = []
+  exe "%" . XfdoCmd
+  call assert_equal(['Xtestfile1 1L 3C', 'Xtestfile2 2L 2C', 'Xtestfile3 2L 3C'], l)
+
+  let l = []
+  exe "1,$" . XfdoCmd
+  call assert_equal(['Xtestfile1 1L 3C', 'Xtestfile2 2L 2C', 'Xtestfile3 2L 3C'], l)
+
+  let l = []
+  exe Xpfile
+  exe "." . XfdoCmd
+  call assert_equal(['Xtestfile2 2L 2C'], l)
+
+  " List with only one valid entry
+  let l = []
+  exe Xgetexpr . " ['Xtestfile2:2:5:Line2']"
+  exe XfdoCmd
+  call assert_equal(['Xtestfile2 2L 5C'], l)
+
+endfunction
+
+" Tests for cdo and cfdo
+function Test_cdo()
+  call XdoTests('c')
+  call XfdoTests('c')
+endfunction
+
+" Tests for ldo and lfdo
+function Test_ldo()
+  call XdoTests('l')
+  call XfdoTests('l')
+endfunction