patch 8.0.1514: getting the list of changes is not easy

Problem:    Getting the list of changes is not easy.
Solution:   Add the getchangelist() function. (Yegappan Lakshmanan,
            closes #2634)
diff --git a/src/testdir/Make_all.mak b/src/testdir/Make_all.mak
index 2d98fa6..e3230c5 100644
--- a/src/testdir/Make_all.mak
+++ b/src/testdir/Make_all.mak
@@ -75,6 +75,7 @@
 	    test_breakindent.res \
 	    test_bufwintabinfo.res \
 	    test_cdo.res \
+	    test_changelist.res \
 	    test_channel.res \
 	    test_charsearch.res \
 	    test_cindent.res \
diff --git a/src/testdir/test_changelist.vim b/src/testdir/test_changelist.vim
new file mode 100644
index 0000000..0880fce
--- /dev/null
+++ b/src/testdir/test_changelist.vim
@@ -0,0 +1,48 @@
+" Tests for the changelist functionality
+
+" Tests for the getchangelist() function
+func Test_getchangelist()
+  if !has("jumplist")
+    return
+  endif
+
+  bwipe!
+  enew
+  call assert_equal([], getchangelist(10))
+  call assert_equal([[], 0], getchangelist(bufnr('%')))
+
+  call writefile(['line1', 'line2', 'line3'], 'Xfile1.txt')
+  call writefile(['line1', 'line2', 'line3'], 'Xfile2.txt')
+
+  edit Xfile1.txt
+  exe "normal 1Goline\<C-G>u1.1"
+  exe "normal 3Goline\<C-G>u2.1"
+  exe "normal 5Goline\<C-G>u3.1"
+  normal g;
+  call assert_equal([[
+	      \ {'lnum' : 2, 'col' : 4, 'coladd' : 0},
+	      \ {'lnum' : 4, 'col' : 4, 'coladd' : 0},
+	      \ {'lnum' : 6, 'col' : 4, 'coladd' : 0}], 2],
+	      \ getchangelist(bufnr('%')))
+
+  hide edit Xfile2.txt
+  exe "normal 1GOline\<C-G>u1.0"
+  exe "normal 2Goline\<C-G>u2.0"
+  call assert_equal([[
+	      \ {'lnum' : 1, 'col' : 6, 'coladd' : 0},
+	      \ {'lnum' : 3, 'col' : 6, 'coladd' : 0}], 2],
+	      \ getchangelist(bufnr('%')))
+  hide enew
+
+  call assert_equal([[
+	      \ {'lnum' : 2, 'col' : 4, 'coladd' : 0},
+	      \ {'lnum' : 4, 'col' : 4, 'coladd' : 0},
+	      \ {'lnum' : 6, 'col' : 4, 'coladd' : 0}], 3], getchangelist(2))
+  call assert_equal([[
+	      \ {'lnum' : 1, 'col' : 6, 'coladd' : 0},
+	      \ {'lnum' : 3, 'col' : 6, 'coladd' : 0}], 2], getchangelist(3))
+
+  bwipe!
+  call delete('Xfile1.txt')
+  call delete('Xfile2.txt')
+endfunc