functests: Ensure different SIDs on successive source() calls

test/functional/ex_cmds/echo_spec.lua

@@ -137,7 +137,7 @@ describe(':echo', function()
     end)
 
     it('dumps references to script functions', function()
-      eq('<SNR>1_Test2', eval('String(Test2_f)'))
+      eq('<SNR>2_Test2', eval('String(Test2_f)'))
     end)
 
     it('dumps partials with self referencing a partial', function()
@@ -156,9 +156,9 @@ describe(':echo', function()
     end)
 
     it('dumps automatically created partials', function()
-      eq('function(\'<SNR>1_Test2\', {\'f\': function(\'<SNR>1_Test2\')})',
+      eq('function(\'<SNR>2_Test2\', {\'f\': function(\'<SNR>2_Test2\')})',
          eval('String({"f": Test2_f}.f)'))
-      eq('function(\'<SNR>1_Test2\', [1], {\'f\': function(\'<SNR>1_Test2\', [1])})',
+      eq('function(\'<SNR>2_Test2\', [1], {\'f\': function(\'<SNR>2_Test2\', [1])})',
          eval('String({"f": function(Test2_f, [1])}.f)'))
     end)
 
@@ -176,8 +176,8 @@ describe(':echo', function()
       meths.set_var('d', {v=true})
       eq(dedent([[
 
-          {'p': function('<SNR>1_Test2', {...@0}), 'f': function('<SNR>1_Test2'), 'v': v:true}
+          {'p': function('<SNR>2_Test2', {...@0}), 'f': function('<SNR>2_Test2'), 'v': v:true}
-          {'p': function('<SNR>1_Test2', {...@0}), 'f': function('<SNR>1_Test2'), 'v': v:true}]]),
+          {'p': function('<SNR>2_Test2', {...@0}), 'f': function('<SNR>2_Test2'), 'v': v:true}]]),
         redir_exec('echo String(extend(extend(g:d, {"f": g:Test2_f}), {"p": g:d.f}))'))
     end)
 
@@ -217,8 +217,8 @@ describe(':echo', function()
       eval('add(l, function("Test1", d))')
       eq(dedent([=[
 
-          {'p': function('<SNR>1_Test2', [[[...@3], function('Test1', [[...@3]]), function('Test1', {...@0})], function('Test1', [[[...@5], function('Test1', [[...@5]]), function('Test1', {...@0})]]), function('Test1', {...@0})], {...@0}), 'f': function('<SNR>1_Test2'), 'v': v:true}
+          {'p': function('<SNR>2_Test2', [[[...@3], function('Test1', [[...@3]]), function('Test1', {...@0})], function('Test1', [[[...@5], function('Test1', [[...@5]]), function('Test1', {...@0})]]), function('Test1', {...@0})], {...@0}), 'f': function('<SNR>2_Test2'), 'v': v:true}
-          {'p': function('<SNR>1_Test2', [[[...@3], function('Test1', [[...@3]]), function('Test1', {...@0})], function('Test1', [[[...@5], function('Test1', [[...@5]]), function('Test1', {...@0})]]), function('Test1', {...@0})], {...@0}), 'f': function('<SNR>1_Test2'), 'v': v:true}]=]),
+          {'p': function('<SNR>2_Test2', [[[...@3], function('Test1', [[...@3]]), function('Test1', {...@0})], function('Test1', [[[...@5], function('Test1', [[...@5]]), function('Test1', {...@0})]]), function('Test1', {...@0})], {...@0}), 'f': function('<SNR>2_Test2'), 'v': v:true}]=]),
         redir_exec('echo String(extend(extend(g:d, {"f": g:Test2_f}), {"p": function(g:d.f, l)}))'))
     end)
   end)

test/functional/helpers.lua

@@ -337,11 +337,23 @@ local function read_file(name)
   return ret
 end
 
+local sourced_fnames = {}
 local function source(code)
   local fname = tmpname()
   write_file(fname, code)
   nvim_command('source '..fname)
-  os.remove(fname)
+  -- DO NOT REMOVE FILE HERE.
+  -- do_source() has a habit of checking whether files are “same” by using inode
+  -- and device IDs. If you run two source() calls in quick succession there is
+  -- a good chance that underlying filesystem will reuse the inode, making files
+  -- appear as “symlinks” to do_source when it checks FileIDs. With current
+  -- setup linux machines (both QB, travis and mine(ZyX-I) with XFS) do reuse
+  -- inodes, Mac OS machines (again, both QB and travis) do not.
+  --
+  -- Files appearing as “symlinks” mean that both the first and the second
+  -- source() calls will use same SID, which may fail some tests which check for
+  -- exact numbers after `<SNR>` in e.g. function names.
+  sourced_fnames[#sourced_fnames + 1] = fname
   return fname
 end
 
@@ -673,6 +685,9 @@ local module = {
 return function(after_each)
   if after_each then
     after_each(function()
+      for _, fname in ipairs(sourced_fnames) do
+        os.remove(fname)
+      end
       check_logs()
       check_cores('build/bin/nvim')
     end)