vim-patch:8.1.0347: some tests fail on Solaris

Problem:    Some tests fail on Solaris.
Solution:   Skip writefile test. Fix path to libc.so. Improve test for Turkish
            case change. (Libor Bukata, Bjorn Linse, closes vim/vim#3403)
f1c118be93

src/nvim/testdir/test_functions.vim

@@ -1,4 +1,5 @@
 " Tests for various functions.
+source shared.vim
 
 " Must be done first, since the alternate buffer must be unset.
 func Test_00_bufexists()
@@ -1150,6 +1151,17 @@ func Test_libcall_libcallnr()
     let libc = 'msvcrt.dll'
   elseif has('mac')
     let libc = 'libSystem.B.dylib'
+  elseif system('uname -s') =~ 'SunOS'
+    " Set the path to libc.so according to the architecture.
+    let test_bits = system('file ' . GetVimProg())
+    let test_arch = system('uname -p')
+    if test_bits =~ '64-bit' && test_arch =~ 'sparc'
+      let libc = '/usr/lib/sparcv9/libc.so'
+    elseif test_bits =~ '64-bit' && test_arch =~ 'i386'
+      let libc = '/usr/lib/amd64/libc.so'
+    else
+      let libc = '/usr/lib/libc.so'
+    endif
   else
     " On Unix, libc.so can be in various places.
     " Interestingly, using an empty string for the 1st argument of libcall

src/nvim/testdir/test_writefile.vim

@@ -33,7 +33,7 @@ func Test_writefile_fails_gently()
 endfunc
 
 func Test_writefile_fails_conversion()
-  if !has('multi_byte') || !has('iconv')
+  if !has('multi_byte') || !has('iconv') || system('uname -s') =~ 'SunOS'
     return
   endif
   " Without a backup file the write won't happen if there is a conversion