vim-patch:7.4.2051

Problem:    No proper testing of trunc_string().
Solution:   Add a unittest for message.c.

https://github.com/vim/vim/commit/502ae4ba63561c98ac69af26cd9883bfd18d225f

4 files changed, 60 insertions, 11 deletions

diff --git a/src/nvim/message.c b/src/nvim/message.c
index 699f4b87b9..57f7369e73 100644
--- a/src/nvim/message.c
+++ b/src/nvim/message.c
@@ -257,7 +257,7 @@ void trunc_string(char_u *s, char_u *buf, int room, int buflen)
       return;
     }
     n = ptr2cells(s + e);
-    if (len + n >= half)
+    if (len + n > half)
       break;
     len += n;
     buf[e] = s[e];
diff --git a/src/nvim/version.c b/src/nvim/version.c
index 8fd9b4b74f..b755404a58 100644
--- a/src/nvim/version.c
+++ b/src/nvim/version.c
@@ -389,7 +389,7 @@ static int included_patches[] = {
   // 2054 NA
   // 2053 NA
   // 2052 NA
-  // 2051,
+  2051,
   2050,
   2049,
   // 2048 NA
diff --git a/test/functional/ui/inccommand_spec.lua b/test/functional/ui/inccommand_spec.lua
index 6da22b6a3a..3b31da0397 100644
--- a/test/functional/ui/inccommand_spec.lua
+++ b/test/functional/ui/inccommand_spec.lua
@@ -482,7 +482,7 @@ describe(":substitute, 'inccommand' preserves undo", function()
           {15:~                   }|
           {15:~                   }|
           {15:~                   }|
-          Already...st change |
+          Already ...t change |
         ]])
       else
         screen:expect([[
@@ -495,7 +495,7 @@ describe(":substitute, 'inccommand' preserves undo", function()
           {15:~                   }|
           {15:~                   }|
           {15:~                   }|
-          Already...st change |
+          Already ...t change |
         ]])
       end
     end
@@ -534,7 +534,7 @@ describe(":substitute, 'inccommand' preserves undo", function()
           {15:~                   }|
           {15:~                   }|
           {15:~                   }|
-          Already...st change |
+          Already ...t change |
         ]])
       else
         screen:expect([[
@@ -547,7 +547,7 @@ describe(":substitute, 'inccommand' preserves undo", function()
           {15:~                   }|
           {15:~                   }|
           {15:~                   }|
-          Already...st change |
+          Already ...t change |
         ]])
       end
 
@@ -574,7 +574,7 @@ describe(":substitute, 'inccommand' preserves undo", function()
           {15:~                   }|
           {15:~                   }|
           {15:~                   }|
-          Already...st change |
+          Already ...t change |
         ]])
       else
         screen:expect([[
@@ -587,7 +587,7 @@ describe(":substitute, 'inccommand' preserves undo", function()
           {15:~                   }|
           {15:~                   }|
           {15:~                   }|
-          Already...st change |
+          Already ...t change |
         ]])
       end
       screen:detach()
@@ -616,7 +616,7 @@ describe(":substitute, 'inccommand' preserves undo", function()
           {15:~                   }|
           {15:~                   }|
           {15:~                   }|
-          Already...st change |
+          Already ...t change |
         ]])
       else
         screen:expect([[
@@ -629,7 +629,7 @@ describe(":substitute, 'inccommand' preserves undo", function()
           {15:~                   }|
           {15:~                   }|
           {15:~                   }|
-          Already...st change |
+          Already ...t change |
         ]])
       end
 
@@ -653,7 +653,7 @@ describe(":substitute, 'inccommand' preserves undo", function()
         {15:~                   }|
         {15:~                   }|
         {15:~                   }|
-        Already...st change |
+        Already ...t change |
       ]])
     end
     screen:detach()
diff --git a/test/unit/message_spec.lua b/test/unit/message_spec.lua
new file mode 100644
index 0000000000..23d342c027
--- /dev/null
+++ b/test/unit/message_spec.lua
@@ -0,0 +1,49 @@
+local helpers = require("test.unit.helpers")
+
+local ffi = helpers.ffi
+local eq = helpers.eq
+local to_cstr = helpers.to_cstr
+
+local cimp = helpers.cimport('./src/nvim/message.h')
+
+describe('trunc_string', function()
+  local buffer = ffi.typeof('char_u[40]')
+
+  local function test_inplace(s, expected)
+    local buf = buffer()
+    ffi.C.strcpy(buf, s)
+    cimp.trunc_string(buf, buf, 20, 40)
+    eq(expected, ffi.string(buf))
+  end
+
+  local function test_copy(s, expected)
+    local buf = buffer()
+    cimp.trunc_string(to_cstr(s), buf, 20, 40)
+    eq(expected, ffi.string(buf))
+  end
+
+  local permutations = {
+    { ['desc'] = 'in-place', ['func'] = test_inplace },
+    { ['desc'] = 'by copy', ['func'] = test_copy },
+  }
+
+  for _,t in ipairs(permutations) do
+    describe('populates buf '..t.desc, function()
+      it('with a small string', function()
+        t.func('text', 'text')
+      end)
+
+      it('with a medium string', function()
+        t.func('a short text', 'a short text')
+      end)
+
+      it('with a string exactly the truncate size', function()
+        t.func('a text tha just fits', 'a text tha just fits')
+      end)
+
+      it('with a string that must be truncated', function()
+        t.func('a text that nott fits', 'a text t...nott fits')
+      end)
+    end)
+  end
+end)