vim-patch:8.1.2269: tags file with very long line stops using binary search

Problem:    Tags file with very long line stops using binary search.
Solution:   Reallocate the buffer if needed.
dc9ef26845

src/nvim/tag.c

@@ -1659,12 +1659,9 @@ find_tags(
             break;              /* End the binary search without a match. */
           else
             search_info.curr_offset = offset;
-        }
+        } else if (state == TS_SKIP_BACK) {
-        /*
+          // Skipping back (after a match during binary search).
-         * Skipping back (after a match during binary search).
+          search_info.curr_offset -= lbuf_size * 2;
-         */
-        else if (state == TS_SKIP_BACK) {
-          search_info.curr_offset -= LSIZE * 2;
           if (search_info.curr_offset < 0) {
             search_info.curr_offset = 0;
             rewind(fp);
@@ -1680,7 +1677,7 @@ find_tags(
           /* Adjust the search file offset to the correct position */
           search_info.curr_offset_used = search_info.curr_offset;
           vim_fseek(fp, search_info.curr_offset, SEEK_SET);
-          eof = vim_fgets(lbuf, LSIZE, fp);
+          eof = vim_fgets(lbuf, lbuf_size, fp);
           if (!eof && search_info.curr_offset != 0) {
             /* The explicit cast is to work around a bug in gcc 3.4.2
              * (repeated below). */
@@ -1690,12 +1687,12 @@ find_tags(
               vim_fseek(fp, search_info.low_offset, SEEK_SET);
               search_info.curr_offset = search_info.low_offset;
             }
-            eof = vim_fgets(lbuf, LSIZE, fp);
+            eof = vim_fgets(lbuf, lbuf_size, fp);
           }
           /* skip empty and blank lines */
           while (!eof && vim_isblankline(lbuf)) {
             search_info.curr_offset = vim_ftell(fp);
-            eof = vim_fgets(lbuf, LSIZE, fp);
+            eof = vim_fgets(lbuf, lbuf_size, fp);
           }
           if (eof) {
             /* Hit end of file.  Skip backwards. */
@@ -1711,10 +1708,9 @@ find_tags(
         else {
           /* skip empty and blank lines */
           do {
-            if (use_cscope)
+            eof = use_cscope
-              eof = cs_fgets(lbuf, LSIZE);
+              ? cs_fgets(lbuf, lbuf_size)
-            else
+              : vim_fgets(lbuf, lbuf_size, fp);
-              eof = vim_fgets(lbuf, LSIZE, fp);
           } while (!eof && vim_isblankline(lbuf));
 
           if (eof) {
@@ -1839,19 +1835,14 @@ parse_line:
         // When the line is too long the NUL will not be in the
         // last-but-one byte (see vim_fgets()).
         // Has been reported for Mozilla JS with extremely long names.
-        // In that case we can't parse it and we ignore the line.
+        // In that case we need to increase lbuf_size.
-        if (lbuf[LSIZE - 2] != NUL && !use_cscope) {
+        if (lbuf[lbuf_size - 2] != NUL && !use_cscope) {
-          if (p_verbose >= 5) {
+          lbuf_size *= 2;
-            verbose_enter();
+          xfree(lbuf);
-            MSG(_("Ignoring long line in tags file"));
+          lbuf = xmalloc(lbuf_size);
-            verbose_leave();
+          // this will try the same thing again, make sure the offset is
-          }
+          // different
-          if (state != TS_LINEAR) {
+          search_info.curr_offset = 0;
-            // Avoid getting stuck.
-            linear = true;
-            state = TS_LINEAR;
-            vim_fseek(fp, search_info.low_offset, SEEK_SET);
-          }
           continue;
         }
 
@@ -2654,6 +2645,9 @@ static int jumpto_tag(
   str = tagp.command;
   for (pbuf_end = pbuf; *str && *str != '\n' && *str != '\r'; ) {
     *pbuf_end++ = *str++;
+    if (pbuf_end - pbuf + 1 >= LSIZE) {
+      break;
+    }
   }
   *pbuf_end = NUL;
 

src/nvim/testdir/test_tagjump.vim

@@ -449,7 +449,8 @@ func Test_tag_line_toolong()
     call assert_report(v:exception)
   catch /.*/
   endtry
-  call assert_equal('Ignoring long line in tags file', split(execute('messages'), '\n')[-1])
+  call assert_equal('Searching tags file Xtags', split(execute('messages'), '\n')[-1])
+
   call writefile([
 	\ '123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567	django/contrib/admin/templates/admin/edit_inline/stacked.html	16;"	j	line:16	language:HTML'
 	\ ], 'Xtags')
@@ -460,8 +461,26 @@ func Test_tag_line_toolong()
     call assert_report(v:exception)
   catch /.*/
   endtry
-  call assert_equal('Ignoring long line in tags file', split(execute('messages'), '\n')[-1])
+  call assert_equal('Searching tags file Xtags', split(execute('messages'), '\n')[-1])
+
+  " binary search works in file with long line
+  call writefile([
+        \ 'asdfasfd	nowhere	16',
+	\ 'foobar	Xsomewhere	3; " 12345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567',
+        \ 'zasdfasfd	nowhere	16',
+	\ ], 'Xtags')
+  call writefile([
+        \ 'one',
+        \ 'two',
+        \ 'trhee',
+        \ 'four',
+        \ ], 'Xsomewhere')
+  tag foobar
+  call assert_equal('Xsomewhere', expand('%'))
+  call assert_equal(3, getcurpos()[1])
+
   call delete('Xtags')
+  call delete('Xsomewhere')
   set tags&
   let &verbose = old_vbs
 endfunc