feat(api): nvim_exec2(), deprecate nvim_exec() #19032

Problem:
The signature of nvim_exec() is not extensible per ":help api-contract".

Solution:
Introduce nvim_exec2() and deprecate nvim_exec().

3 files changed, 8 insertions, 9 deletions

diff --git a/test/functional/core/exit_spec.lua b/test/functional/core/exit_spec.lua
index dc4b45b4d9..d474b77806 100644
--- a/test/functional/core/exit_spec.lua
+++ b/test/functional/core/exit_spec.lua
@@ -93,14 +93,14 @@ describe(':cquit', function()
   end)
 
   it('exits with redir msg for multiple exit codes after :cquit 1 2', function()
-    test_cq('cquit 1 2', nil, 'nvim_exec(): Vim(cquit):E488: Trailing characters: 2: cquit 1 2')
+    test_cq('cquit 1 2', nil, 'nvim_exec2(): Vim(cquit):E488: Trailing characters: 2: cquit 1 2')
   end)
 
   it('exits with redir msg for non-number exit code after :cquit X', function()
-    test_cq('cquit X', nil, 'nvim_exec(): Vim(cquit):E488: Trailing characters: X: cquit X')
+    test_cq('cquit X', nil, 'nvim_exec2(): Vim(cquit):E488: Trailing characters: X: cquit X')
   end)
 
   it('exits with redir msg for negative exit code after :cquit -1', function()
-    test_cq('cquit -1', nil, 'nvim_exec(): Vim(cquit):E488: Trailing characters: -1: cquit -1')
+    test_cq('cquit -1', nil, 'nvim_exec2(): Vim(cquit):E488: Trailing characters: -1: cquit -1')
   end)
 end)
diff --git a/test/functional/core/remote_spec.lua b/test/functional/core/remote_spec.lua
index 846d79abf3..b2a1679023 100644
--- a/test/functional/core/remote_spec.lua
+++ b/test/functional/core/remote_spec.lua
@@ -101,7 +101,7 @@ describe('Remote', function()
     expect(contents)
     eq(1, #funcs.getbufinfo())
     -- Since we didn't pass silent, we should get a complaint
-    neq(nil, string.find(meths.exec('messages', true), 'E247'))
+    neq(nil, string.find(meths.exec2('messages', { output = true }).output, 'E247'))
   end)
 
   it('creates server if not found with tabs', function()
@@ -110,7 +110,7 @@ describe('Remote', function()
     eq(2, #funcs.gettabinfo())
     eq(2, #funcs.getbufinfo())
     -- We passed silent, so no message should be issued about the server not being found
-    eq(nil, string.find(meths.exec('messages', true), 'E247'))
+    eq(nil, string.find(meths.exec2('messages', { output = true }).output, 'E247'))
   end)
 
   pending('exits with error on', function()
diff --git a/test/functional/core/startup_spec.lua b/test/functional/core/startup_spec.lua
index e9b47a0251..4ae8b1c95e 100644
--- a/test/functional/core/startup_spec.lua
+++ b/test/functional/core/startup_spec.lua
@@ -58,7 +58,7 @@ describe('startup', function()
       ^                                                            |
                                                                   |
       Entering Debug mode.  Type "cont" to continue.              |
-      nvim_exec()                                                 |
+      nvim_exec2()                                                |
       cmd: aunmenu *                                              |
       >                                                           |
                                                                   |
@@ -691,7 +691,6 @@ describe('sysinit', function()
     eq('loaded 1 xdg 0 vim 1',
        eval('printf("loaded %d xdg %d vim %d", g:loaded, get(g:, "xdg", 0), get(g:, "vim", 0))'))
   end)
-
 end)
 
 describe('user config init', function()
@@ -824,7 +823,7 @@ describe('user config init', function()
       clear{ args_rm={'-u'}, env=xenv }
       feed('<cr><c-c>')  -- Dismiss "Conflicting config …" message.
       eq(1, eval('g:lua_rc'))
-      matches('^E5422: Conflicting configs', meths.exec('messages', true))
+      matches('^E5422: Conflicting configs', meths.exec2('messages', { output = true }).output)
     end)
   end)
 end)
@@ -873,7 +872,7 @@ describe('runtime:', function()
 
     eq(2, eval('g:lua_plugin'))
     -- Check if plugin_file_path is listed in :scriptname
-    local scripts = meths.exec(':scriptnames', true)
+    local scripts = meths.exec2(':scriptnames', { output = true }).output
     assert(scripts:find(plugin_file_path))
 
     -- Check if plugin_file_path is listed in startup profile