t6022: Additional tests checking for unnecessary updates of files

diff --git a/pretty.c b/pretty.c
index 85499347514ec3e1d62d6caa9f53b886c556e345..7d23c1f8481af3cfd73c76c76fb2e13a2a7e4a9c 100644 (file)
--- a/pretty.c
+++ b/pretty.c
@@ -208,6 +208,58 @@ int has_non_ascii(const char *s)
        return 0;
 }
 
+static int is_rfc822_special(char ch)
+{
+       switch (ch) {
+       case '(':
+       case ')':
+       case '<':
+       case '>':
+       case '[':
+       case ']':
+       case ':':
+       case ';':
+       case '@':
+       case ',':
+       case '.':
+       case '"':
+       case '\\':
+               return 1;
+       default:
+               return 0;
+       }
+}
+
+static int has_rfc822_specials(const char *s, int len)
+{
+       int i;
+       for (i = 0; i < len; i++)
+               if (is_rfc822_special(s[i]))
+                       return 1;
+       return 0;
+}
+
+static void add_rfc822_quoted(struct strbuf *out, const char *s, int len)
+{
+       int i;
+
+       /* just a guess, we may have to also backslash-quote */
+       strbuf_grow(out, len + 2);
+
+       strbuf_addch(out, '"');
+       for (i = 0; i < len; i++) {
+               switch (s[i]) {
+               case '"':
+               case '\\':
+                       strbuf_addch(out, '\\');
+                       /* fall through */
+               default:
+                       strbuf_addch(out, s[i]);
+               }
+       }
+       strbuf_addch(out, '"');
+}
+
 static int is_rfc2047_special(char ch)
 {
        return (non_ascii(ch) || (ch == '=') || (ch == '?') || (ch == '_'));
@@ -216,36 +268,53 @@ static int is_rfc2047_special(char ch)
 static void add_rfc2047(struct strbuf *sb, const char *line, int len,
                       const char *encoding)
 {
-       int i, last;
+       static const int max_length = 78; /* per rfc2822 */
+       int i;
+       int line_len;
+
+       /* How many bytes are already used on the current line? */
+       for (i = sb->len - 1; i >= 0; i--)
+               if (sb->buf[i] == '\n')
+                       break;
+       line_len = sb->len - (i+1);
 
        for (i = 0; i < len; i++) {
                int ch = line[i];
-               if (non_ascii(ch))
+               if (non_ascii(ch) || ch == '\n')
                        goto needquote;
                if ((i + 1 < len) && (ch == '=' && line[i+1] == '?'))
                        goto needquote;
        }
-       strbuf_add(sb, line, len);
+       strbuf_add_wrapped_bytes(sb, line, len, 0, 1, max_length - line_len);
        return;
 
 needquote:
        strbuf_grow(sb, len * 3 + strlen(encoding) + 100);
        strbuf_addf(sb, "=?%s?q?", encoding);
-       for (i = last = 0; i < len; i++) {
+       line_len += strlen(encoding) + 5; /* 5 for =??q? */
+       for (i = 0; i < len; i++) {
                unsigned ch = line[i] & 0xFF;
+
+               if (line_len >= max_length - 2) {
+                       strbuf_addf(sb, "?=\n =?%s?q?", encoding);
+                       line_len = strlen(encoding) + 5 + 1; /* =??q? plus SP */
+               }
+
                /*
                 * We encode ' ' using '=20' even though rfc2047
                 * allows using '_' for readability.  Unfortunately,
                 * many programs do not understand this and just
                 * leave the underscore in place.
                 */
-               if (is_rfc2047_special(ch) || ch == ' ') {
-                       strbuf_add(sb, line + last, i - last);
+               if (is_rfc2047_special(ch) || ch == ' ' || ch == '\n') {
                        strbuf_addf(sb, "=%02X", ch);
-                       last = i + 1;
+                       line_len += 3;
+               }
+               else {
+                       strbuf_addch(sb, ch);
+                       line_len++;
                }
        }
-       strbuf_add(sb, line + last, len - last);
        strbuf_addstr(sb, "?=");
 }
 
@@ -276,7 +345,14 @@ void pp_user_info(const char *what, enum cmit_fmt fmt, struct strbuf *sb,
                        name_tail--;
                display_name_length = name_tail - line;
                strbuf_addstr(sb, "From: ");
-               add_rfc2047(sb, line, display_name_length, encoding);
+               if (!has_rfc822_specials(line, display_name_length)) {
+                       add_rfc2047(sb, line, display_name_length, encoding);
+               } else {
+                       struct strbuf quoted = STRBUF_INIT;
+                       add_rfc822_quoted(&quoted, line, display_name_length);
+                       add_rfc2047(sb, quoted.buf, quoted.len, encoding);
+                       strbuf_release(&quoted);
+               }
                strbuf_add(sb, name_tail, namelen - display_name_length);
                strbuf_addch(sb, '\n');
        } else {
@@ -859,11 +935,7 @@ static size_t format_commit_one(struct strbuf *sb, const char *placeholder,
                                              c->abbrev_parent_hashes.off;
                return 1;
        case 'm':               /* left/right/bottom */
-               strbuf_addch(sb, (commit->object.flags & BOUNDARY)
-                                ? '-'
-                                : (commit->object.flags & SYMMETRIC_LEFT)
-                                ? '<'
-                                : '>');
+               strbuf_addstr(sb, get_revision_mark(NULL, commit));
                return 1;
        case 'd':
                format_decoration(sb, commit);
@@ -1003,7 +1075,7 @@ void userformat_find_requirements(const char *fmt, struct userformat_want *w)
                        return;
                fmt = user_format;
        }
-       strbuf_expand(&dummy, user_format, userformat_want_item, w);
+       strbuf_expand(&dummy, fmt, userformat_want_item, w);
        strbuf_release(&dummy);
 }
 
@@ -1106,11 +1178,10 @@ void pp_title_line(enum cmit_fmt fmt,
                   const char *encoding,
                   int need_8bit_cte)
 {
-       const char *line_separator = (fmt == CMIT_FMT_EMAIL) ? "\n " : " ";
        struct strbuf title;
 
        strbuf_init(&title, 80);
-       *msg_p = format_subject(&title, *msg_p, line_separator);
+       *msg_p = format_subject(&title, *msg_p, " ");
 
        strbuf_grow(sb, title.len + 1024);
        if (subject) {