patch 8.2.0156: various typos in source files and tests

Problem:    Various typos in source files and tests.
Solution:   Fix the typos. (Emir Sari, closes #5532)
diff --git a/src/testdir/test_breakindent.vim b/src/testdir/test_breakindent.vim
index f7cfb4e..6e4e090 100644
--- a/src/testdir/test_breakindent.vim
+++ b/src/testdir/test_breakindent.vim
@@ -1,7 +1,7 @@
 " Test for breakindent
 "
 " Note: if you get strange failures when adding new tests, it might be that
-" while the test is run, the breakindent cacheing gets in its way.
+" while the test is run, the breakindent caching gets in its way.
 " It helps to change the tabstop setting and force a redraw (e.g. see
 " Test_breakindent08())
 source check.vim
diff --git a/src/testdir/test_channel.vim b/src/testdir/test_channel.vim
index dace45b..bd442c2 100644
--- a/src/testdir/test_channel.vim
+++ b/src/testdir/test_channel.vim
@@ -20,7 +20,7 @@
 
 let s:chopt = {}
 
-" Run "testfunc" after sarting the server and stop the server afterwards.
+" Run "testfunc" after starting the server and stop the server afterwards.
 func s:run_server(testfunc, ...)
   call RunServer('test_channel.py', a:testfunc, a:000)
 endfunc
@@ -425,7 +425,7 @@
 
   " We intend to use a socket that doesn't exist and wait for half a second
   " before giving up.  If the socket does exist it can fail in various ways.
-  " Check for "Connection reset by peer" to avoid flakyness.
+  " Check for "Connection reset by peer" to avoid flakiness.
   let start = reltime()
   try
     let handle = ch_open('localhost:9867', {'waittime': 500})
diff --git a/src/testdir/test_cindent.vim b/src/testdir/test_cindent.vim
index 2d78be1..dfafd01 100644
--- a/src/testdir/test_cindent.vim
+++ b/src/testdir/test_cindent.vim
@@ -815,7 +815,7 @@
         }
      }
 
-  public: // <-- this was incorectly indented before!!
+  public: // <-- this was incorrectly indented before!!
      void testfall();
   protected:
      void testfall();
@@ -1780,7 +1780,7 @@
   		}
   	}
 
-  	public: // <-- this was incorectly indented before!!
+  	public: // <-- this was incorrectly indented before!!
   	void testfall();
   	protected:
   	void testfall();
@@ -5254,9 +5254,12 @@
 " this was going beyond the end of the line.
 func Test_cindent_case()
   new
-  call setline(1, "case x: // x")
+  call setline(1, 'case x: // x')
   set cindent
   norm! f:a:
+  call assert_equal('case x:: // x', getline(1))
+
+  set cindent&
   bwipe!
 endfunc
 
diff --git a/src/testdir/test_digraph.vim b/src/testdir/test_digraph.vim
index 6435c86..e66663b 100644
--- a/src/testdir/test_digraph.vim
+++ b/src/testdir/test_digraph.vim
@@ -80,7 +80,7 @@
   call Put_Dig(".e")
   call Put_Dig("a.") " not defined
   call assert_equal(['ḃ', 'ė', '.'], getline(line('.')-2,line('.')))
-  " Diaresis
+  " Diaeresis
   call Put_Dig("a:")
   call Put_Dig(":u")
   call Put_Dig("b:") " not defined
@@ -285,7 +285,7 @@
   call Put_Dig_BS(".","e")
   call Put_Dig_BS("a",".") " not defined
   call assert_equal(['ḃ', 'ė', '.'], getline(line('.')-2,line('.')))
-  " Diaresis
+  " Diaeresis
   call Put_Dig_BS("a",":")
   call Put_Dig_BS(":","u")
   call Put_Dig_BS("b",":") " not defined
diff --git a/src/testdir/test_edit.vim b/src/testdir/test_edit.vim
index 4e29e7f..1a37146 100644
--- a/src/testdir/test_edit.vim
+++ b/src/testdir/test_edit.vim
@@ -589,7 +589,7 @@
   call feedkeys("A\<c-x>\<c-k>\<down>\<down>\<down>\<down>\<cr>\<esc>", 'tnix')
   call assert_equal(['AA'], getline(1, '$'))
 
-  " press an unexecpted key after dictionary completion
+  " press an unexpected key after dictionary completion
   %d
   call setline(1, 'A')
   call cursor(1, 1)
diff --git a/src/testdir/test_netbeans.vim b/src/testdir/test_netbeans.vim
index 690ac67..61da44d 100644
--- a/src/testdir/test_netbeans.vim
+++ b/src/testdir/test_netbeans.vim
@@ -10,7 +10,7 @@
   throw 'Skipped: python program missing'
 endif
 
-" Run "testfunc" after sarting the server and stop the server afterwards.
+" Run "testfunc" after starting the server and stop the server afterwards.
 func s:run_server(testfunc, ...)
   call RunServer('test_netbeans.py', a:testfunc, a:000)
 endfunc
diff --git a/src/testdir/test_quickfix.vim b/src/testdir/test_quickfix.vim
index b7b4281..129b1cf 100644
--- a/src/testdir/test_quickfix.vim
+++ b/src/testdir/test_quickfix.vim
@@ -2629,7 +2629,7 @@
   call assert_equal('quickfix', getwinvar(1, '&buftype'))
   call assert_equal('quickfix', getwinvar(3, '&buftype'))
 
-  " Jumping to a file from the location list window should find a usuable
+  " Jumping to a file from the location list window should find a usable
   " window by wrapping around the window list.
   enew | only
   call setloclist(0, [], 'f')
diff --git a/src/testdir/test_registers.vim b/src/testdir/test_registers.vim
index b6bce46..45cf02a 100644
--- a/src/testdir/test_registers.vim
+++ b/src/testdir/test_registers.vim
@@ -274,7 +274,7 @@
   call setreg('=', 'b', 'a')
   call assert_equal('regwrite', getreg('='))
 
-  " Test for settting a list of lines to special registers
+  " Test for setting a list of lines to special registers
   call setreg('/', [])
   call assert_equal('', @/)
   call setreg('=', [])
diff --git a/src/testdir/test_stat.vim b/src/testdir/test_stat.vim
index c8830d1..ccd5950 100644
--- a/src/testdir/test_stat.vim
+++ b/src/testdir/test_stat.vim
@@ -5,7 +5,7 @@
   let times = []
   let result = 0
 
-  " Use three files istead of localtim(), with a network filesystem the file
+  " Use three files instead of localtim(), with a network filesystem the file
   " times may differ at bit
   let fl = ['Hello World!']
   for fname in fnames