vim-patch:8.2.0943: displaying ^M or ^J depends on current buffer

Problem:    Displaying ^M or ^J depends on current buffer.
Solution:   Pass the displayed buffer to transchar(). (closes vim/vim#6225)
32ee627750

N/A patches for version.c:

vim-patch:8.2.0862: ":term ++curwin" makes the current buffer hidden

Problem:    ":term ++curwin" makes the current buffer hidden. (Harm te
            Hennepe)
Solution:   Do not hide the current buffer. (closes vim/vim#6170)
b10090928c

src/nvim/charset.c

@@ -509,7 +509,7 @@ char_u* str_foldcase(char_u *str, int orglen, char_u *buf, int buflen)
 // Does NOT work for multi-byte characters, c must be <= 255.
 // Also doesn't work for the first byte of a multi-byte, "c" must be a
 // character!
-static char_u transchar_buf[11];
+static char_u transchar_charbuf[11];
 
 /// Translate a character into a printable one, leaving printable ASCII intact
 ///
@@ -519,12 +519,18 @@ static char_u transchar_buf[11];
 ///
 /// @return translated character into a static buffer.
 char_u *transchar(int c)
+{
+  return transchar_buf(curbuf, c);
+}
+
+char_u *transchar_buf(const buf_T *buf, int c)
+  FUNC_ATTR_NONNULL_ALL
 {
   int i = 0;
   if (IS_SPECIAL(c)) {
     // special key code, display as ~@ char
-    transchar_buf[0] = '~';
+    transchar_charbuf[0] = '~';
-    transchar_buf[1] = '@';
+    transchar_charbuf[1] = '@';
     i = 2;
     c = K_SECOND(c);
   }
@@ -532,14 +538,14 @@ char_u *transchar(int c)
   if ((!chartab_initialized && (((c >= ' ') && (c <= '~'))))
       || ((c <= 0xFF) && vim_isprintc_strict(c))) {
     // printable character
-    transchar_buf[i] = (char_u)c;
+    transchar_charbuf[i] = (char_u)c;
-    transchar_buf[i + 1] = NUL;
+    transchar_charbuf[i + 1] = NUL;
   } else if (c <= 0xFF) {
-    transchar_nonprint(transchar_buf + i, c);
+    transchar_nonprint(buf, transchar_charbuf + i, c);
   } else {
-    transchar_hex((char *)transchar_buf + i, c);
+    transchar_hex((char *)transchar_charbuf + i, c);
   }
-  return transchar_buf;
+  return transchar_charbuf;
 }
 
 /// Like transchar(), but called with a byte instead of a character
@@ -548,13 +554,13 @@ char_u *transchar(int c)
 ///
 /// @param[in]  c  Byte to translate.
 ///
-/// @return pointer to translated character in transchar_buf.
+/// @return pointer to translated character in transchar_charbuf.
 char_u *transchar_byte(const int c)
   FUNC_ATTR_WARN_UNUSED_RESULT
 {
   if (c >= 0x80) {
-    transchar_nonprint(transchar_buf, c);
+    transchar_nonprint(curbuf, transchar_charbuf, c);
-    return transchar_buf;
+    return transchar_charbuf;
   }
   return transchar(c);
 }
@@ -563,16 +569,18 @@ char_u *transchar_byte(const int c)
 ///
 /// @warning Does not work for multi-byte characters, c must be <= 255.
 ///
-/// @param[out]  buf  Buffer to store result in, must be able to hold at least
+/// @param[in]  buf  Required to check the file format
-///                   5 bytes (conversion result + NUL).
+/// @param[out]  charbuf  Buffer to store result in, must be able to hold
+///                       at least 5 bytes (conversion result + NUL).
 /// @param[in]  c  Character to convert. NUL is assumed to be NL according to
 ///                `:h NL-used-for-NUL`.
-void transchar_nonprint(char_u *buf, int c)
+void transchar_nonprint(const buf_T *buf, char_u *charbuf, int c)
+  FUNC_ATTR_NONNULL_ALL
 {
   if (c == NL) {
     // we use newline in place of a NUL
     c = NUL;
-  } else if ((c == CAR) && (get_fileformat(curbuf) == EOL_MAC)) {
+  } else if ((c == CAR) && (get_fileformat(buf) == EOL_MAC)) {
     // we use CR in place of  NL in this case
     c = NL;
   }
@@ -580,14 +588,14 @@ void transchar_nonprint(char_u *buf, int c)
 
   if (dy_flags & DY_UHEX || c > 0x7f) {
     // 'display' has "uhex"
-    transchar_hex((char *)buf, c);
+    transchar_hex((char *)charbuf, c);
   } else {
     // 0x00 - 0x1f and 0x7f
-    buf[0] = '^';
+    charbuf[0] = '^';
     // DEL displayed as ^?
-    buf[1] = (char_u)(c ^ 0x40);
+    charbuf[1] = (char_u)(c ^ 0x40);
 
-    buf[2] = NUL;
+    charbuf[2] = NUL;
   }
 }
 

src/nvim/ex_cmds.c

@@ -135,7 +135,7 @@ void do_ascii(const exarg_T *const eap)
     char buf1[20];
     if (vim_isprintc_strict(c) && (c < ' ' || c > '~')) {
       char_u buf3[7];
-      transchar_nonprint(buf3, c);
+      transchar_nonprint(curbuf, buf3, c);
       vim_snprintf(buf1, sizeof(buf1), "  <%s>", (char *)buf3);
     } else {
       buf1[0] = NUL;
@@ -2240,11 +2240,9 @@ int do_ecmd(
     goto theend;
   }
 
-  /*
+  // If the file was changed we may not be allowed to abandon it:
-   * if the file was changed we may not be allowed to abandon it
+  // - if we are going to re-edit the same file
-   * - if we are going to re-edit the same file
+  // - or if we are the only window on this file and if ECMD_HIDE is FALSE
-   * - or if we are the only window on this file and if ECMD_HIDE is FALSE
-   */
   if (  ((!other_file && !(flags & ECMD_OLDBUF))
          || (curbuf->b_nwindows == 1
              && !(flags & (ECMD_HIDE | ECMD_ADDBUF))))

src/nvim/message.c

@@ -1621,7 +1621,7 @@ const char *str2special(const char **const sp, const bool replace_spaces,
 
     // Check for an illegal byte.
     if (MB_BYTE2LEN((uint8_t)(*str)) > len) {
-      transchar_nonprint((char_u *)buf, c);
+      transchar_nonprint(curbuf, (char_u *)buf, c);
       *sp = str + 1;
       return buf;
     }

src/nvim/option.c

@@ -7270,7 +7270,8 @@ unsigned int get_bkc_value(buf_T *buf)
 }
 
 /// Return the current end-of-line type: EOL_DOS, EOL_UNIX or EOL_MAC.
-int get_fileformat(buf_T *buf)
+int get_fileformat(const buf_T *buf)
+  FUNC_ATTR_PURE FUNC_ATTR_WARN_UNUSED_RESULT FUNC_ATTR_NONNULL_ALL
 {
   int c = *buf->b_p_ff;
 

src/nvim/screen.c

@@ -3634,7 +3634,7 @@ static int win_line(win_T *wp, linenr_T lnum, int startrow, int endrow,
             mb_utf8 = false;                    // don't draw as UTF-8
           }
         } else if (c != NUL) {
-          p_extra = transchar(c);
+          p_extra = transchar_buf(wp->w_buffer, c);
           if (n_extra == 0) {
               n_extra = byte2cells(c) - 1;
           }

src/nvim/testdir/test_display.vim

@@ -202,6 +202,30 @@ func Test_edit_long_file_name()
   call delete(longName)
 endfunc
 
+func Test_unprintable_fileformats()
+  CheckScreendump
+
+  call writefile(["unix\r", "two"], 'Xunix.txt')
+  call writefile(["mac\r", "two"], 'Xmac.txt')
+  let lines =<< trim END
+    edit Xunix.txt
+    split Xmac.txt
+    edit ++ff=mac
+  END
+  let filename = 'Xunprintable'
+  call writefile(lines, filename)
+  let buf = RunVimInTerminal('-S '.filename, #{rows: 9, cols: 50})
+  call VerifyScreenDump(buf, 'Test_display_unprintable_01', {})
+  call term_sendkeys(buf, "\<C-W>\<C-W>\<C-L>")
+  call VerifyScreenDump(buf, 'Test_display_unprintable_02', {})
+
+  " clean up
+  call StopVimInTerminal(buf)
+  call delete('Xunix.txt')
+  call delete('Xmac.txt')
+  call delete(filename)
+endfunc
+
 " Test for scrolling that modifies buffer during visual block
 func Test_visual_block_scroll()
   " See test/functional/legacy/visual_mode_spec.lua