patch 9.1.1626: cindent: does not handle compound literals

Problem:  C-indent does not handle compound literals
          (@44100hertz, @Jorenar)
Solution: Detect and handle compound literal and structure
          initialization (Anttoni Erkkilä)

match '=' or "return" optionally followed by &, (typecast), {
Fixes also initialization which begins with multiple opening braces.

fixes: #2090
fixes: #12491
closes: #17865

Signed-off-by: Anttoni Erkkilä <anttoni.erkkila@protonmail.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>

runtime/doc/version9.txt

@@ -1,4 +1,4 @@
-*version9.txt*  For Vim version 9.1.  Last change: 2025 Aug 08
+*version9.txt*  For Vim version 9.1.  Last change: 2025 Aug 12
 
 
 		  VIM REFERENCE MANUAL    by Bram Moolenaar
@@ -41736,6 +41736,7 @@ Others: ~
 - |gv| works in operator pending mode and does not abort
 - The close button shown in the non-GUI 'tabline' will only be visible if the
   'mouse' option contains either "a" or any of the flags "n", "v", or "i".
+- |C-indenting| handles compound literals.
 
 							*added-9.2*
 Added ~

src/cindent.c

@@ -690,10 +690,9 @@ cin_islabel(void)		// XXX
 /*
  * Return TRUE if string "s" ends with the string "find", possibly followed by
  * white space and comments.  Skip strings and comments.
- * Ignore "ignore" after "find" if it's not NULL.
  */
     static int
-cin_ends_in(char_u *s, char_u *find, char_u *ignore)
+cin_ends_in(char_u *s, char_u *find)
 {
     char_u	*p = s;
     char_u	*r;
@@ -705,8 +704,6 @@ cin_ends_in(char_u *s, char_u *find, char_u *ignore)
 	if (STRNCMP(p, find, len) == 0)
 	{
 	    r = skipwhite(p + len);
-	    if (ignore != NULL && STRNCMP(r, ignore, STRLEN(ignore)) == 0)
-		r = skipwhite(r + STRLEN(ignore));
 	    if (cin_nocode(r))
 		return TRUE;
 	}
@@ -717,9 +714,77 @@ cin_ends_in(char_u *s, char_u *find, char_u *ignore)
 }
 
 /*
- * Recognize structure initialization and enumerations:
+ * Strings can be concatenated with comments between:
+ * "string0" |*comment*| "string1"
+ */
+    static char_u *
+cin_skip_comment_and_string(char_u *s)
+{
+    char_u *r = NULL, *p = s;
+    do
+    {
+	r = p;
+	p = cin_skipcomment(p);
+	if (*p)
+	    p = skip_string(p);
+    } while (p != r);
+    return p;
+}
+
+/*
+ * Recognize structure or compound literal initialization:
+ * =|return [&][(typecast)] [{]
+ * The number of opening braces is arbitrary.
+ */
+    static int
+cin_is_compound_init(char_u *s)
+{
+    char_u *p = s, *r = NULL;
+
+    while (*p)
+    {
+	if (*p == '=')
+	    p = r = cin_skipcomment(p + 1);
+	else if (!STRNCMP(p, "return", 6) && !vim_isIDc(p[6])
+		&& (p == s || (p > s && !vim_isIDc(p[-1]))))
+	    p = r = cin_skipcomment(p + 6);
+	else
+	    p = cin_skip_comment_and_string(p + 1);
+    }
+    if (!r)
+	return FALSE;
+    p = r; // p points now after '=' or "return"
+
+    if (cin_nocode(p))
+	return TRUE;
+
+    if (*p == '&')
+	p = cin_skipcomment(p + 1);
+
+    if (*p == '(') // skip a typecast
+    {
+	int open_count = 1;
+	do
+	{
+	    p = cin_skip_comment_and_string(p + 1);
+	    if (cin_nocode(p))
+		return TRUE;
+	    open_count += (*p == '(') - (*p == ')');
+	} while (open_count);
+	p = cin_skipcomment(p + 1);
+	if (cin_nocode(p))
+	    return TRUE;
+    }
+
+    while (*p == '{')
+	p = cin_skipcomment(p + 1);
+    return cin_nocode(p);
+}
+
+/*
+ * Recognize enumerations:
  * "[typedef] [static|public|protected|private] enum"
- * "[typedef] [static|public|protected|private] = {"
+ * Call another function to recognize structure initialization.
  */
     static int
 cin_isinit(void)
@@ -753,10 +818,7 @@ cin_isinit(void)
     if (cin_starts_with(s, "enum"))
 	return TRUE;
 
-    if (cin_ends_in(s, (char_u *)"=", (char_u *)"{"))
-	return TRUE;
-
-    return FALSE;
+    return cin_is_compound_init(s);
 }
 
 // Maximum number of lines to search back for a "namespace" line.
@@ -1634,7 +1696,7 @@ get_baseclass_amount(int col)
 	if (find_last_paren(ml_get_curline(), '(', ')')
 		&& (trypos = find_match_paren(curbuf->b_ind_maxparen)) != NULL)
 	    amount = get_indent_lnum(trypos->lnum); // XXX
-	if (!cin_ends_in(ml_get_curline(), (char_u *)",", NULL))
+	if (!cin_ends_in(ml_get_curline(), (char_u *)","))
 	    amount += curbuf->b_ind_cpp_baseclass;
     }
     else
@@ -2505,7 +2567,7 @@ get_c_indent(void)
 		    cur_amount = MAXCOL;
 		    l = ml_get(our_paren_pos.lnum);
 		    if (curbuf->b_ind_unclosed_wrapped
-				       && cin_ends_in(l, (char_u *)"(", NULL))
+				       && cin_ends_in(l, (char_u *)"("))
 		    {
 			// look for opening unmatched paren, indent one level
 			// for each additional level
@@ -3702,8 +3764,8 @@ term_again:
 	    && !cin_nocode(theline)
 	    && vim_strchr(theline, '{') == NULL
 	    && vim_strchr(theline, '}') == NULL
-	    && !cin_ends_in(theline, (char_u *)":", NULL)
-	    && !cin_ends_in(theline, (char_u *)",", NULL)
+	    && !cin_ends_in(theline, (char_u *)":")
+	    && !cin_ends_in(theline, (char_u *)",")
 	    && cin_isfuncdecl(NULL, cur_curpos.lnum + 1,
 			      cur_curpos.lnum + 1)
 	    && !cin_isterminated(theline, FALSE, TRUE))
@@ -3764,7 +3826,7 @@ term_again:
 	// } foo,
 	//   bar;
 	n = 0;
-	if (cin_ends_in(l, (char_u *)",", NULL)
+	if (cin_ends_in(l, (char_u *)",")
 		     || (*l != NUL && (n = l[STRLEN(l) - 1]) == '\\'))
 	{
 	    // take us back to opening paren
@@ -3812,14 +3874,14 @@ term_again:
 	// comments) align at column 0.  For example:
 	// char *string_array[] = { "foo",
 	//     / * x * / "b};ar" }; / * foobar * /
-	if (cin_ends_in(l, (char_u *)"};", NULL))
+	if (cin_ends_in(l, (char_u *)"};"))
 	    break;
 
 	// If the previous line ends on '[' we are probably in an
 	// array constant:
 	// something = [
 	//     234,  <- extra indent
-	if (cin_ends_in(l, (char_u *)"[", NULL))
+	if (cin_ends_in(l, (char_u *)"["))
 	{
 	    amount = get_indent() + ind_continuation;
 	    break;
@@ -3840,7 +3902,7 @@ term_again:
 		    break;
 	    }
 	    if (curwin->w_cursor.lnum > 0
-			    && cin_ends_in(look, (char_u *)"}", NULL))
+			    && cin_ends_in(look, (char_u *)"}"))
 		break;
 
 	    curwin->w_cursor = curpos_save;
@@ -3860,10 +3922,10 @@ term_again:
 	// int foo,
 	//     bar;
 	// indent_to_0 here;
-	if (cin_ends_in(l, (char_u *)";", NULL))
+	if (cin_ends_in(l, (char_u *)";"))
 	{
 	    l = ml_get(curwin->w_cursor.lnum - 1);
-	    if (cin_ends_in(l, (char_u *)",", NULL)
+	    if (cin_ends_in(l, (char_u *)",")
 		    || (*l != NUL && l[STRLEN(l) - 1] == '\\'))
 		break;
 	    l = ml_get_curline();

src/testdir/test_indent.vim

@@ -119,6 +119,31 @@ func Test_userlabel_indent()
   close!
 endfunc
 
+" Test that struct members are aligned
+func Test_struct_indent()
+  new
+  call setline(1, ['struct a a = {', '1,', '1,'])
+  normal gg=G
+  call assert_equal(getline(2), getline(3))
+
+  call setline(1, 'a = (struct a) {')
+  normal gg=G
+  call assert_equal(getline(2), getline(3))
+
+  call setline(1, 'void *ptr = &(static struct a) {{')
+  normal gg=G
+  call assert_equal(getline(2), getline(3))
+
+  call setline(1, 'a = (macro(arg1, "str)))")) {')
+  normal gg=G
+  call assert_equal(getline(2), getline(3))
+
+  call setline(1, 'return (struct a) {')
+  normal gg=G
+  call assert_equal(getline(2), getline(3))
+  close!
+endfunc
+
 " Test for 'copyindent'
 func Test_copyindent()
   new

src/version.c

@@ -719,6 +719,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    1626,
 /**/
     1625,
 /**/