Code

Merge branch 'jc/maint-1.6.0-blank-at-eof' (early part) into jc/maint-blank-at-eof
[git.git] / diff.c
diff --git a/diff.c b/diff.c
index cd35e0c2d7e29012e24cc8f5f49d9d351420b56e..87a3e8956be3592f42d2bb560dadf72f1fb72576 100644 (file)
--- a/diff.c
+++ b/diff.c
@@ -532,8 +532,12 @@ static void diff_words_show(struct diff_words_data *diff_words)
 typedef unsigned long (*sane_truncate_fn)(char *line, unsigned long len);
 
 struct emit_callback {
-       int nparents, color_diff;
+       int color_diff;
        unsigned ws_rule;
+       int blank_at_eof_in_preimage;
+       int blank_at_eof_in_postimage;
+       int lno_in_preimage;
+       int lno_in_postimage;
        sane_truncate_fn truncate;
        const char **label_path;
        struct diff_words_data *diff_words;
@@ -586,6 +590,17 @@ static void emit_line(FILE *file, const char *set, const char *reset, const char
                fputc('\n', file);
 }
 
+static int new_blank_line_at_eof(struct emit_callback *ecbdata, const char *line, int len)
+{
+       if (!((ecbdata->ws_rule & WS_BLANK_AT_EOF) &&
+             ecbdata->blank_at_eof_in_preimage &&
+             ecbdata->blank_at_eof_in_postimage &&
+             ecbdata->blank_at_eof_in_preimage <= ecbdata->lno_in_preimage &&
+             ecbdata->blank_at_eof_in_postimage <= ecbdata->lno_in_postimage))
+               return 0;
+       return ws_blank_line(line + 1, len - 1, ecbdata->ws_rule);
+}
+
 static void emit_add_line(const char *reset, struct emit_callback *ecbdata, const char *line, int len)
 {
        const char *ws = diff_get_color(ecbdata->color_diff, DIFF_WHITESPACE);
@@ -593,11 +608,13 @@ static void emit_add_line(const char *reset, struct emit_callback *ecbdata, cons
 
        if (!*ws)
                emit_line(ecbdata->file, set, reset, line, len);
+       else if (new_blank_line_at_eof(ecbdata, line, len))
+               /* Blank line at EOF - paint '+' as well */
+               emit_line(ecbdata->file, ws, reset, line, len);
        else {
                /* Emit just the prefix, then the rest. */
-               emit_line(ecbdata->file, set, reset, line, ecbdata->nparents);
-               ws_check_emit(line + ecbdata->nparents,
-                             len - ecbdata->nparents, ecbdata->ws_rule,
+               emit_line(ecbdata->file, set, reset, line, 1);
+               ws_check_emit(line + 1, len - 1, ecbdata->ws_rule,
                              ecbdata->file, set, reset, ws);
        }
 }
@@ -620,10 +637,23 @@ static unsigned long sane_truncate_line(struct emit_callback *ecb, char *line, u
        return allot - l;
 }
 
+static void find_lno(const char *line, struct emit_callback *ecbdata)
+{
+       const char *p;
+       ecbdata->lno_in_preimage = 0;
+       ecbdata->lno_in_postimage = 0;
+       p = strchr(line, '-');
+       if (!p)
+               return; /* cannot happen */
+       ecbdata->lno_in_preimage = strtol(p + 1, NULL, 10);
+       p = strchr(p, '+');
+       if (!p)
+               return; /* cannot happen */
+       ecbdata->lno_in_postimage = strtol(p + 1, NULL, 10);
+}
+
 static void fn_out_consume(void *priv, char *line, unsigned long len)
 {
-       int i;
-       int color;
        struct emit_callback *ecbdata = priv;
        const char *meta = diff_get_color(ecbdata->color_diff, DIFF_METAINFO);
        const char *plain = diff_get_color(ecbdata->color_diff, DIFF_PLAIN);
@@ -650,14 +680,9 @@ static void fn_out_consume(void *priv, char *line, unsigned long len)
                len = 1;
        }
 
-       /* This is not really necessary for now because
-        * this codepath only deals with two-way diffs.
-        */
-       for (i = 0; i < len && line[i] == '@'; i++)
-               ;
-       if (2 <= i && i < len && line[i] == ' ') {
-               ecbdata->nparents = i - 1;
+       if (line[0] == '@') {
                len = sane_truncate_line(ecbdata, line, len);
+               find_lno(line, ecbdata);
                emit_line(ecbdata->file,
                          diff_get_color(ecbdata->color_diff, DIFF_FRAGINFO),
                          reset, line, len);
@@ -666,15 +691,11 @@ static void fn_out_consume(void *priv, char *line, unsigned long len)
                return;
        }
 
-       if (len < ecbdata->nparents) {
+       if (len < 1) {
                emit_line(ecbdata->file, reset, reset, line, len);
                return;
        }
 
-       color = DIFF_PLAIN;
-       if (ecbdata->diff_words && ecbdata->nparents != 1)
-               /* fall back to normal diff */
-               free_diff_words_data(ecbdata);
        if (ecbdata->diff_words) {
                if (line[0] == '-') {
                        diff_words_append(line, len,
@@ -693,20 +714,19 @@ static void fn_out_consume(void *priv, char *line, unsigned long len)
                emit_line(ecbdata->file, plain, reset, line, len);
                return;
        }
-       for (i = 0; i < ecbdata->nparents && len; i++) {
-               if (line[i] == '-')
-                       color = DIFF_FILE_OLD;
-               else if (line[i] == '+')
-                       color = DIFF_FILE_NEW;
-       }
 
-       if (color != DIFF_FILE_NEW) {
-               emit_line(ecbdata->file,
-                         diff_get_color(ecbdata->color_diff, color),
-                         reset, line, len);
-               return;
+       if (line[0] != '+') {
+               const char *color =
+                       diff_get_color(ecbdata->color_diff,
+                                      line[0] == '-' ? DIFF_FILE_OLD : DIFF_PLAIN);
+               ecbdata->lno_in_preimage++;
+               if (line[0] == ' ')
+                       ecbdata->lno_in_postimage++;
+               emit_line(ecbdata->file, color, reset, line, len);
+       } else {
+               ecbdata->lno_in_postimage++;
+               emit_add_line(reset, ecbdata, line, len);
        }
-       emit_add_line(reset, ecbdata, line, len);
 }
 
 static char *pprint_rename(const char *a, const char *b)
@@ -1211,7 +1231,6 @@ struct checkdiff_t {
        struct diff_options *o;
        unsigned ws_rule;
        unsigned status;
-       int trailing_blanks_start;
 };
 
 static int is_conflict_marker(const char *line, unsigned long len)
@@ -1255,10 +1274,6 @@ static void checkdiff_consume(void *priv, char *line, unsigned long len)
        if (line[0] == '+') {
                unsigned bad;
                data->lineno++;
-               if (!ws_blank_line(line + 1, len - 1, data->ws_rule))
-                       data->trailing_blanks_start = 0;
-               else if (!data->trailing_blanks_start)
-                       data->trailing_blanks_start = data->lineno;
                if (is_conflict_marker(line + 1, len - 1)) {
                        data->status |= 1;
                        fprintf(data->o->file,
@@ -1278,14 +1293,12 @@ static void checkdiff_consume(void *priv, char *line, unsigned long len)
                              data->o->file, set, reset, ws);
        } else if (line[0] == ' ') {
                data->lineno++;
-               data->trailing_blanks_start = 0;
        } else if (line[0] == '@') {
                char *plus = strchr(line, '+');
                if (plus)
                        data->lineno = strtol(plus, NULL, 10) - 1;
                else
                        die("invalid diff");
-               data->trailing_blanks_start = 0;
        }
 }
 
@@ -1437,6 +1450,51 @@ static const char *get_textconv(struct diff_filespec *one)
        return one->driver->textconv;
 }
 
+static int count_trailing_blank(mmfile_t *mf, unsigned ws_rule)
+{
+       char *ptr = mf->ptr;
+       long size = mf->size;
+       int cnt = 0;
+
+       if (!size)
+               return cnt;
+       ptr += size - 1; /* pointing at the very end */
+       if (*ptr != '\n')
+               ; /* incomplete line */
+       else
+               ptr--; /* skip the last LF */
+       while (mf->ptr < ptr) {
+               char *prev_eol;
+               for (prev_eol = ptr; mf->ptr <= prev_eol; prev_eol--)
+                       if (*prev_eol == '\n')
+                               break;
+               if (!ws_blank_line(prev_eol + 1, ptr - prev_eol, ws_rule))
+                       break;
+               cnt++;
+               ptr = prev_eol - 1;
+       }
+       return cnt;
+}
+
+static void check_blank_at_eof(mmfile_t *mf1, mmfile_t *mf2,
+                              struct emit_callback *ecbdata)
+{
+       int l1, l2, at;
+       unsigned ws_rule = ecbdata->ws_rule;
+       l1 = count_trailing_blank(mf1, ws_rule);
+       l2 = count_trailing_blank(mf2, ws_rule);
+       if (l2 <= l1) {
+               ecbdata->blank_at_eof_in_preimage = 0;
+               ecbdata->blank_at_eof_in_postimage = 0;
+               return;
+       }
+       at = count_lines(mf1->ptr, mf1->size);
+       ecbdata->blank_at_eof_in_preimage = (at - l1) + 1;
+
+       at = count_lines(mf2->ptr, mf2->size);
+       ecbdata->blank_at_eof_in_postimage = (at - l2) + 1;
+}
+
 static void builtin_diff(const char *name_a,
                         const char *name_b,
                         struct diff_filespec *one,
@@ -1562,6 +1620,8 @@ static void builtin_diff(const char *name_a,
                ecbdata.color_diff = DIFF_OPT_TST(o, COLOR_DIFF);
                ecbdata.found_changesp = &o->found_changes;
                ecbdata.ws_rule = whitespace_rule(name_b ? name_b : name_a);
+               if (ecbdata.ws_rule & WS_BLANK_AT_EOF)
+                       check_blank_at_eof(&mf1, &mf2, &ecbdata);
                ecbdata.file = o->file;
                xpp.flags = XDF_NEED_MINIMAL | o->xdl_opts;
                xecfg.ctxlen = o->context;
@@ -1704,11 +1764,22 @@ static void builtin_checkdiff(const char *name_a, const char *name_b,
                xdi_diff_outf(&mf1, &mf2, checkdiff_consume, &data,
                              &xpp, &xecfg, &ecb);
 
-               if ((data.ws_rule & WS_TRAILING_SPACE) &&
-                   data.trailing_blanks_start) {
-                       fprintf(o->file, "%s:%d: ends with blank lines.\n",
-                               data.filename, data.trailing_blanks_start);
-                       data.status = 1; /* report errors */
+               if (data.ws_rule & WS_BLANK_AT_EOF) {
+                       struct emit_callback ecbdata;
+                       int blank_at_eof;
+
+                       ecbdata.ws_rule = data.ws_rule;
+                       check_blank_at_eof(&mf1, &mf2, &ecbdata);
+                       blank_at_eof = ecbdata.blank_at_eof_in_preimage;
+
+                       if (blank_at_eof) {
+                               static char *err;
+                               if (!err)
+                                       err = whitespace_error_string(WS_BLANK_AT_EOF);
+                               fprintf(o->file, "%s:%d: %s.\n",
+                                       data.filename, blank_at_eof, err);
+                               data.status = 1; /* report errors */
+                       }
                }
        }
  free_and_return: