Merge pull request #25934 from bfredl/screenlinechar

refactor(grid): make screen rendering more multibyte than ever before

3 files changed, 50 insertions, 22 deletions

diff --git a/test/functional/ui/fold_spec.lua b/test/functional/ui/fold_spec.lua
index 9a0182ea29..1addf7088e 100644
--- a/test/functional/ui/fold_spec.lua
+++ b/test/functional/ui/fold_spec.lua
@@ -1102,8 +1102,6 @@ describe("folded lines", function()
     end)
 
     it("works with multibyte text", function()
-      -- Currently the only allowed value of 'maxcombine'
-      eq(6, meths.get_option_value('maxcombine', {}))
       eq(true, meths.get_option_value('arabicshape', {}))
       insert([[
         å 语 x̨̣̘̫̲͚͎̎͂̀̂͛͛̾͢͟ العَرَبِيَّة
@@ -1120,7 +1118,7 @@ describe("folded lines", function()
           [2:---------------------------------------------]|
           [3:---------------------------------------------]|
         ## grid 2
-          å 语 x̎͂̀̂͛͛ ﺎﻠﻋَﺮَﺒِﻳَّﺓ                               |
+          å 语 x̨̣̘̫̲͚͎̎͂̀̂͛͛̾͢ ﺎﻠﻋَﺮَﺒِﻳَّﺓ                               |
           möre tex^t                                    |
           {1:~                                            }|
           {1:~                                            }|
@@ -1132,7 +1130,7 @@ describe("folded lines", function()
         ]])
       else
         screen:expect([[
-          å 语 x̎͂̀̂͛͛ ﺎﻠﻋَﺮَﺒِﻳَّﺓ                               |
+          å 语 x̨̣̘̫̲͚͎̎͂̀̂͛͛̾͢ ﺎﻠﻋَﺮَﺒِﻳَّﺓ                               |
           möre tex^t                                    |
           {1:~                                            }|
           {1:~                                            }|
@@ -1156,7 +1154,7 @@ describe("folded lines", function()
           [2:---------------------------------------------]|
           [3:---------------------------------------------]|
         ## grid 2
-          {5:^+--  2 lines: å 语 x̎͂̀̂͛͛ ﺎﻠﻋَﺮَﺒِﻳَّﺓ·················}|
+          {5:^+--  2 lines: å 语 x̨̣̘̫̲͚͎̎͂̀̂͛͛̾͢ ﺎﻠﻋَﺮَﺒِﻳَّﺓ·················}|
           {1:~                                            }|
           {1:~                                            }|
           {1:~                                            }|
@@ -1168,7 +1166,7 @@ describe("folded lines", function()
         ]])
       else
         screen:expect([[
-          {5:^+--  2 lines: å 语 x̎͂̀̂͛͛ ﺎﻠﻋَﺮَﺒِﻳَّﺓ·················}|
+          {5:^+--  2 lines: å 语 x̨̣̘̫̲͚͎̎͂̀̂͛͛̾͢ ﺎﻠﻋَﺮَﺒِﻳَّﺓ·················}|
           {1:~                                            }|
           {1:~                                            }|
           {1:~                                            }|
@@ -1192,7 +1190,7 @@ describe("folded lines", function()
           [2:---------------------------------------------]|
           [3:---------------------------------------------]|
         ## grid 2
-          {5:^+--  2 lines: å 语 x̎͂̀̂͛͛ العَرَبِيَّة·················}|
+          {5:^+--  2 lines: å 语 x̨̣̘̫̲͚͎̎͂̀̂͛͛̾͢ العَرَبِيَّة·················}|
           {1:~                                            }|
           {1:~                                            }|
           {1:~                                            }|
@@ -1204,7 +1202,7 @@ describe("folded lines", function()
         ]])
       else
         screen:expect([[
-          {5:^+--  2 lines: å 语 x̎͂̀̂͛͛ العَرَبِيَّة·················}|
+          {5:^+--  2 lines: å 语 x̨̣̘̫̲͚͎̎͂̀̂͛͛̾͢ العَرَبِيَّة·················}|
           {1:~                                            }|
           {1:~                                            }|
           {1:~                                            }|
@@ -1228,7 +1226,7 @@ describe("folded lines", function()
           [2:---------------------------------------------]|
           [3:---------------------------------------------]|
         ## grid 2
-          {7:+ }{8:  1 }{5:^+--  2 lines: å 语 x̎͂̀̂͛͛ العَرَبِيَّة···········}|
+          {7:+ }{8:  1 }{5:^+--  2 lines: å 语 x̨̣̘̫̲͚͎̎͂̀̂͛͛̾͢ العَرَبِيَّة···········}|
           {1:~                                            }|
           {1:~                                            }|
           {1:~                                            }|
@@ -1240,7 +1238,7 @@ describe("folded lines", function()
         ]])
       else
         screen:expect([[
-          {7:+ }{8:  1 }{5:^+--  2 lines: å 语 x̎͂̀̂͛͛ العَرَبِيَّة···········}|
+          {7:+ }{8:  1 }{5:^+--  2 lines: å 语 x̨̣̘̫̲͚͎̎͂̀̂͛͛̾͢ العَرَبِيَّة···········}|
           {1:~                                            }|
           {1:~                                            }|
           {1:~                                            }|
@@ -1265,7 +1263,7 @@ describe("folded lines", function()
           [2:---------------------------------------------]|
           [3:---------------------------------------------]|
         ## grid 2
-          {5:···········ةيَّبِرَعَلا x̎͂̀̂͛͛ 语 å :senil 2  --^+}{8: 1  }{7: +}|
+          {5:···········ةيَّبِرَعَلا x̨̣̘̫̲͚͎̎͂̀̂͛͛̾͢ 语 å :senil 2  --^+}{8: 1  }{7: +}|
           {1:                                            ~}|
           {1:                                            ~}|
           {1:                                            ~}|
@@ -1277,7 +1275,7 @@ describe("folded lines", function()
         ]])
       else
         screen:expect([[
-          {5:···········ةيَّبِرَعَلا x̎͂̀̂͛͛ 语 å :senil 2  --^+}{8: 1  }{7: +}|
+          {5:···········ةيَّبِرَعَلا x̨̣̘̫̲͚͎̎͂̀̂͛͛̾͢ 语 å :senil 2  --^+}{8: 1  }{7: +}|
           {1:                                            ~}|
           {1:                                            ~}|
           {1:                                            ~}|
@@ -1301,7 +1299,7 @@ describe("folded lines", function()
           [2:---------------------------------------------]|
           [3:---------------------------------------------]|
         ## grid 2
-          {5:·················ةيَّبِرَعَلا x̎͂̀̂͛͛ 语 å :senil 2  --^+}|
+          {5:·················ةيَّبِرَعَلا x̨̣̘̫̲͚͎̎͂̀̂͛͛̾͢ 语 å :senil 2  --^+}|
           {1:                                            ~}|
           {1:                                            ~}|
           {1:                                            ~}|
@@ -1313,7 +1311,7 @@ describe("folded lines", function()
         ]])
       else
         screen:expect([[
-          {5:·················ةيَّبِرَعَلا x̎͂̀̂͛͛ 语 å :senil 2  --^+}|
+          {5:·················ةيَّبِرَعَلا x̨̣̘̫̲͚͎̎͂̀̂͛͛̾͢ 语 å :senil 2  --^+}|
           {1:                                            ~}|
           {1:                                            ~}|
           {1:                                            ~}|
@@ -1337,7 +1335,7 @@ describe("folded lines", function()
           [2:---------------------------------------------]|
           [3:---------------------------------------------]|
         ## grid 2
-          {5:·················ﺔﻴَّﺑِﺮَﻌَﻟﺍ x̎͂̀̂͛͛ 语 å :senil 2  --^+}|
+          {5:·················ﺔﻴَّﺑِﺮَﻌَﻟﺍ x̨̣̘̫̲͚͎̎͂̀̂͛͛̾͢ 语 å :senil 2  --^+}|
           {1:                                            ~}|
           {1:                                            ~}|
           {1:                                            ~}|
@@ -1349,7 +1347,7 @@ describe("folded lines", function()
         ]])
       else
         screen:expect([[
-          {5:·················ﺔﻴَّﺑِﺮَﻌَﻟﺍ x̎͂̀̂͛͛ 语 å :senil 2  --^+}|
+          {5:·················ﺔﻴَّﺑِﺮَﻌَﻟﺍ x̨̣̘̫̲͚͎̎͂̀̂͛͛̾͢ 语 å :senil 2  --^+}|
           {1:                                            ~}|
           {1:                                            ~}|
           {1:                                            ~}|
@@ -1373,7 +1371,7 @@ describe("folded lines", function()
           [2:---------------------------------------------]|
           [3:---------------------------------------------]|
         ## grid 2
-                                         ﺔﻴَّﺑِﺮَﻌَ^ﻟﺍ x̎͂̀̂͛͛ 语 å|
+                                         ﺔﻴَّﺑِﺮَﻌَ^ﻟﺍ x̨̣̘̫̲͚͎̎͂̀̂͛͛̾͢ 语 å|
                                               txet eröm|
           {1:                                            ~}|
           {1:                                            ~}|
@@ -1385,7 +1383,7 @@ describe("folded lines", function()
         ]])
       else
         screen:expect([[
-                                         ﺔﻴَّﺑِﺮَﻌَ^ﻟﺍ x̎͂̀̂͛͛ 语 å|
+                                         ﺔﻴَّﺑِﺮَﻌَ^ﻟﺍ x̨̣̘̫̲͚͎̎͂̀̂͛͛̾͢ 语 å|
                                               txet eröm|
           {1:                                            ~}|
           {1:                                            ~}|
@@ -1409,7 +1407,7 @@ describe("folded lines", function()
           [2:---------------------------------------------]|
           [3:---------------------------------------------]|
         ## grid 2
-                                         ةيَّبِرَعَ^لا x̎͂̀̂͛͛ 语 å|
+                                         ةيَّبِرَعَ^لا x̨̣̘̫̲͚͎̎͂̀̂͛͛̾͢ 语 å|
                                               txet eröm|
           {1:                                            ~}|
           {1:                                            ~}|
@@ -1421,7 +1419,7 @@ describe("folded lines", function()
         ]])
       else
         screen:expect([[
-                                         ةيَّبِرَعَ^لا x̎͂̀̂͛͛ 语 å|
+                                         ةيَّبِرَعَ^لا x̨̣̘̫̲͚͎̎͂̀̂͛͛̾͢ 语 å|
                                               txet eröm|
           {1:                                            ~}|
           {1:                                            ~}|
diff --git a/test/functional/ui/multibyte_spec.lua b/test/functional/ui/multibyte_spec.lua
index 077dd1a779..d72bf27d6b 100644
--- a/test/functional/ui/multibyte_spec.lua
+++ b/test/functional/ui/multibyte_spec.lua
@@ -228,6 +228,36 @@ describe("multibyte rendering", function()
     ]]}
 
   end)
+
+  it('works with arabicshape and multiple composing chars', function()
+    -- this tests an important edge case: arabicshape might increase the byte size of the base
+    -- character in a way so that the last composing char no longer fits. use "g8" on the text
+    -- to observe what is happening (the final E1 80 B7 gets deleted with 'arabicshape')
+    -- If we would increase the schar_t size, say from 32 to 64 bytes, we need to extend the
+    -- test text with even more zalgo energy to still touch this edge case.
+
+    meths.buf_set_lines(0,0,-1,true, {"سلام့̀́̂̃̄̅̆̇̈̉̊̋̌"})
+    command('set noarabicshape')
+
+    screen:expect{grid=[[
+      ^سلام့̀́̂̃̄̅̆̇̈̉̊̋̌                                                        |
+      {1:~                                                           }|
+      {1:~                                                           }|
+      {1:~                                                           }|
+      {1:~                                                           }|
+                                                                  |
+    ]]}
+
+    command('set arabicshape')
+    screen:expect{grid=[[
+      ^ﺱﻼﻣ̀́̂̃̄̅̆̇̈̉̊̋̌                                                         |
+      {1:~                                                           }|
+      {1:~                                                           }|
+      {1:~                                                           }|
+      {1:~                                                           }|
+                                                                  |
+    ]]}
+  end)
 end)
 
 describe('multibyte rendering: statusline', function()
diff --git a/test/functional/ui/output_spec.lua b/test/functional/ui/output_spec.lua
index 0dd1f0325c..7b93b74eac 100644
--- a/test/functional/ui/output_spec.lua
+++ b/test/functional/ui/output_spec.lua
@@ -225,8 +225,8 @@ describe("shell command :!", function()
         å                                                    |
         ref: å̲                                               |
         1: å̲                                                 |
-        2: å ̲                                               |
-        3: å ̲                                               |
+        2: å ̲                                                |
+        3: å ̲                                                |
                                                              |
         {3:Press ENTER or type command to continue}^              |
       ]])