vim-patch:9.1.2016: cindent wrong indentation after do-while loop (#37087)

Problem:  At "if(0) do if(0); while(0); else", else should be aligned
          with outer if, but is aligned with inner if.
Solution: In function find_match, ignore "if" and "else" inside a
          do-while loop, when looking for "if". (Anttoni Erkkilä)

closes: vim/vim#19004

9d661b057e

Co-authored-by: Anttoni Erkkilä <anttoni.erkkila@protonmail.com>

src/nvim/indent_c.c

@@ -3712,10 +3712,12 @@ static int find_match(int lookfor, linenr_T ourscope)
       continue;
     }
 
+    look = cin_skipcomment(get_cursor_line_ptr());
+    // When looking for if, we ignore "if" and "else" in a deeper do-while loop.
+    if (!(lookfor == LOOKFOR_IF && whilelevel)) {
       // if it was an "else" (that's not an "else if")
       // then we need to go back to another if, so
       // increment elselevel
-    look = cin_skipcomment(get_cursor_line_ptr());
       if (cin_iselse(look)) {
         mightbeif = cin_skipcomment(look + 4);
         if (!cin_isif(mightbeif)) {
@@ -3724,15 +3726,7 @@ static int find_match(int lookfor, linenr_T ourscope)
         continue;
       }
 
-    // if it was a "while" then we need to go back to
-    // another "do", so increment whilelevel.  XXX
-    if (cin_iswhileofdo(look, curwin->w_cursor.lnum)) {
-      whilelevel++;
-      continue;
-    }
-
       // If it's an "if" decrement elselevel
-    look = cin_skipcomment(get_cursor_line_ptr());
       if (cin_isif(look)) {
         elselevel--;
         // When looking for an "if" ignore "while"s that
@@ -3741,6 +3735,14 @@ static int find_match(int lookfor, linenr_T ourscope)
           whilelevel = 0;
         }
       }
+    }
+
+    // if it was a "while" then we need to go back to
+    // another "do", so increment whilelevel.  XXX
+    if (cin_iswhileofdo(look, curwin->w_cursor.lnum)) {
+      whilelevel++;
+      continue;
+    }
 
     // If it's a "do" decrement whilelevel
     if (cin_isdo(look)) {

test/old/testdir/test_cindent.vim

@@ -1106,6 +1106,27 @@ func Test_cindent_1()
   b;
   }
 
+  void func() {
+  if (0)
+  do
+  if (0);
+  while (0);
+  else;
+  }
+
+  void func() {
+  if (0)
+  do
+  if (0)
+  do
+  if (0)
+  a();
+  while (0);
+  while (0);
+  else
+  a();
+  }
+
   /* end of AUTO */
   [CODE]
 
@@ -2088,6 +2109,27 @@ func Test_cindent_1()
   		  b;
   }
 
+  void func() {
+  	if (0)
+  		do
+  			if (0);
+  		while (0);
+  	else;
+  }
+
+  void func() {
+  	if (0)
+  		do
+  			if (0)
+  				do
+  					if (0)
+  						a();
+  				while (0);
+  		while (0);
+  	else
+  		a();
+  }
+
   /* end of AUTO */
 
   [CODE]