subtree: make --ignore-joins pay attention to adds
[gitweb.git] / diff.c
diff --git a/diff.c b/diff.c
index 4c59f5f5d3d32286daefbeeb25ed5291070fe762..f0c7557b40443da060c3070c602dd03f49b0d689 100644 (file)
--- a/diff.c
+++ b/diff.c
@@ -13,6 +13,7 @@
 #include "attr.h"
 #include "run-command.h"
 #include "utf8.h"
+#include "object-store.h"
 #include "userdiff.h"
 #include "submodule-config.h"
 #include "submodule.h"
@@ -22,6 +23,7 @@
 #include "argv-array.h"
 #include "graph.h"
 #include "packfile.h"
+#include "help.h"
 
 #ifdef NO_FAST_WORKING_DIRECTORY
 #define FAST_WORKING_DIRECTORY 0
@@ -35,6 +37,7 @@ static int diff_rename_limit_default = 400;
 static int diff_suppress_blank_empty;
 static int diff_use_color_default = -1;
 static int diff_color_moved_default;
+static int diff_color_moved_ws_default;
 static int diff_context_default = 3;
 static int diff_interhunk_context_default;
 static const char *diff_word_regex_cfg;
@@ -67,6 +70,37 @@ static char diff_colors[][COLOR_MAXLEN] = {
        GIT_COLOR_BOLD_YELLOW,  /* NEW_MOVED ALTERNATIVE */
        GIT_COLOR_FAINT,        /* NEW_MOVED_DIM */
        GIT_COLOR_FAINT_ITALIC, /* NEW_MOVED_ALTERNATIVE_DIM */
+       GIT_COLOR_FAINT,        /* CONTEXT_DIM */
+       GIT_COLOR_FAINT_RED,    /* OLD_DIM */
+       GIT_COLOR_FAINT_GREEN,  /* NEW_DIM */
+       GIT_COLOR_BOLD,         /* CONTEXT_BOLD */
+       GIT_COLOR_BOLD_RED,     /* OLD_BOLD */
+       GIT_COLOR_BOLD_GREEN,   /* NEW_BOLD */
+};
+
+static const char *color_diff_slots[] = {
+       [DIFF_CONTEXT]                = "context",
+       [DIFF_METAINFO]               = "meta",
+       [DIFF_FRAGINFO]               = "frag",
+       [DIFF_FILE_OLD]               = "old",
+       [DIFF_FILE_NEW]               = "new",
+       [DIFF_COMMIT]                 = "commit",
+       [DIFF_WHITESPACE]             = "whitespace",
+       [DIFF_FUNCINFO]               = "func",
+       [DIFF_FILE_OLD_MOVED]         = "oldMoved",
+       [DIFF_FILE_OLD_MOVED_ALT]     = "oldMovedAlternative",
+       [DIFF_FILE_OLD_MOVED_DIM]     = "oldMovedDimmed",
+       [DIFF_FILE_OLD_MOVED_ALT_DIM] = "oldMovedAlternativeDimmed",
+       [DIFF_FILE_NEW_MOVED]         = "newMoved",
+       [DIFF_FILE_NEW_MOVED_ALT]     = "newMovedAlternative",
+       [DIFF_FILE_NEW_MOVED_DIM]     = "newMovedDimmed",
+       [DIFF_FILE_NEW_MOVED_ALT_DIM] = "newMovedAlternativeDimmed",
+       [DIFF_CONTEXT_DIM]            = "contextDimmed",
+       [DIFF_FILE_OLD_DIM]           = "oldDimmed",
+       [DIFF_FILE_NEW_DIM]           = "newDimmed",
+       [DIFF_CONTEXT_BOLD]           = "contextBold",
+       [DIFF_FILE_OLD_BOLD]          = "oldBold",
+       [DIFF_FILE_NEW_BOLD]          = "newBold",
 };
 
 static NORETURN void die_want_option(const char *option_name)
@@ -74,41 +108,13 @@ static NORETURN void die_want_option(const char *option_name)
        die(_("option '%s' requires a value"), option_name);
 }
 
+define_list_config_array_extra(color_diff_slots, {"plain"});
+
 static int parse_diff_color_slot(const char *var)
 {
-       if (!strcasecmp(var, "context") || !strcasecmp(var, "plain"))
+       if (!strcasecmp(var, "plain"))
                return DIFF_CONTEXT;
-       if (!strcasecmp(var, "meta"))
-               return DIFF_METAINFO;
-       if (!strcasecmp(var, "frag"))
-               return DIFF_FRAGINFO;
-       if (!strcasecmp(var, "old"))
-               return DIFF_FILE_OLD;
-       if (!strcasecmp(var, "new"))
-               return DIFF_FILE_NEW;
-       if (!strcasecmp(var, "commit"))
-               return DIFF_COMMIT;
-       if (!strcasecmp(var, "whitespace"))
-               return DIFF_WHITESPACE;
-       if (!strcasecmp(var, "func"))
-               return DIFF_FUNCINFO;
-       if (!strcasecmp(var, "oldmoved"))
-               return DIFF_FILE_OLD_MOVED;
-       if (!strcasecmp(var, "oldmovedalternative"))
-               return DIFF_FILE_OLD_MOVED_ALT;
-       if (!strcasecmp(var, "oldmoveddimmed"))
-               return DIFF_FILE_OLD_MOVED_DIM;
-       if (!strcasecmp(var, "oldmovedalternativedimmed"))
-               return DIFF_FILE_OLD_MOVED_ALT_DIM;
-       if (!strcasecmp(var, "newmoved"))
-               return DIFF_FILE_NEW_MOVED;
-       if (!strcasecmp(var, "newmovedalternative"))
-               return DIFF_FILE_NEW_MOVED_ALT;
-       if (!strcasecmp(var, "newmoveddimmed"))
-               return DIFF_FILE_NEW_MOVED_DIM;
-       if (!strcasecmp(var, "newmovedalternativedimmed"))
-               return DIFF_FILE_NEW_MOVED_ALT_DIM;
-       return -1;
+       return LOOKUP_CONFIG(color_diff_slots, var);
 }
 
 static int parse_dirstat_params(struct diff_options *options, const char *params_string,
@@ -177,7 +183,7 @@ static int parse_submodule_params(struct diff_options *options, const char *valu
        return 0;
 }
 
-static int git_config_rename(const char *var, const char *value)
+int git_config_rename(const char *var, const char *value)
 {
        if (!value)
                return DIFF_DETECT_RENAME;
@@ -271,14 +277,54 @@ static int parse_color_moved(const char *arg)
                return COLOR_MOVED_NO;
        else if (!strcmp(arg, "plain"))
                return COLOR_MOVED_PLAIN;
+       else if (!strcmp(arg, "blocks"))
+               return COLOR_MOVED_BLOCKS;
        else if (!strcmp(arg, "zebra"))
                return COLOR_MOVED_ZEBRA;
        else if (!strcmp(arg, "default"))
                return COLOR_MOVED_DEFAULT;
+       else if (!strcmp(arg, "dimmed-zebra"))
+               return COLOR_MOVED_ZEBRA_DIM;
        else if (!strcmp(arg, "dimmed_zebra"))
                return COLOR_MOVED_ZEBRA_DIM;
        else
-               return error(_("color moved setting must be one of 'no', 'default', 'zebra', 'dimmed_zebra', 'plain'"));
+               return error(_("color moved setting must be one of 'no', 'default', 'blocks', 'zebra', 'dimmed-zebra', 'plain'"));
+}
+
+static int parse_color_moved_ws(const char *arg)
+{
+       int ret = 0;
+       struct string_list l = STRING_LIST_INIT_DUP;
+       struct string_list_item *i;
+
+       string_list_split(&l, arg, ',', -1);
+
+       for_each_string_list_item(i, &l) {
+               struct strbuf sb = STRBUF_INIT;
+               strbuf_addstr(&sb, i->string);
+               strbuf_trim(&sb);
+
+               if (!strcmp(sb.buf, "ignore-space-change"))
+                       ret |= XDF_IGNORE_WHITESPACE_CHANGE;
+               else if (!strcmp(sb.buf, "ignore-space-at-eol"))
+                       ret |= XDF_IGNORE_WHITESPACE_AT_EOL;
+               else if (!strcmp(sb.buf, "ignore-all-space"))
+                       ret |= XDF_IGNORE_WHITESPACE;
+               else if (!strcmp(sb.buf, "allow-indentation-change"))
+                       ret |= COLOR_MOVED_WS_ALLOW_INDENTATION_CHANGE;
+               else
+                       error(_("ignoring unknown color-moved-ws mode '%s'"), sb.buf);
+
+               strbuf_release(&sb);
+       }
+
+       if ((ret & COLOR_MOVED_WS_ALLOW_INDENTATION_CHANGE) &&
+           (ret & XDF_WHITESPACE_FLAGS))
+               die(_("color-moved-ws: allow-indentation-change cannot be combined with other white space modes"));
+
+       string_list_clear(&l, 0);
+
+       return ret;
 }
 
 int git_diff_ui_config(const char *var, const char *value, void *cb)
@@ -294,6 +340,13 @@ int git_diff_ui_config(const char *var, const char *value, void *cb)
                diff_color_moved_default = cm;
                return 0;
        }
+       if (!strcmp(var, "diff.colormovedws")) {
+               int cm = parse_color_moved_ws(value);
+               if (cm < 0)
+                       return -1;
+               diff_color_moved_ws_default = cm;
+               return 0;
+       }
        if (!strcmp(var, "diff.context")) {
                diff_context_default = git_config_int(var, value);
                if (diff_context_default < 0)
@@ -570,37 +623,55 @@ static void check_blank_at_eof(mmfile_t *mf1, mmfile_t *mf2,
        ecbdata->blank_at_eof_in_postimage = (at - l2) + 1;
 }
 
-static void emit_line_0(struct diff_options *o, const char *set, const char *reset,
+static void emit_line_0(struct diff_options *o,
+                       const char *set_sign, const char *set, unsigned reverse, const char *reset,
                        int first, const char *line, int len)
 {
        int has_trailing_newline, has_trailing_carriage_return;
-       int nofirst;
+       int needs_reset = 0; /* at the end of the line */
        FILE *file = o->file;
 
        fputs(diff_line_prefix(o), file);
 
-       if (len == 0) {
-               has_trailing_newline = (first == '\n');
-               has_trailing_carriage_return = (!has_trailing_newline &&
-                                               (first == '\r'));
-               nofirst = has_trailing_newline || has_trailing_carriage_return;
-       } else {
-               has_trailing_newline = (len > 0 && line[len-1] == '\n');
-               if (has_trailing_newline)
-                       len--;
-               has_trailing_carriage_return = (len > 0 && line[len-1] == '\r');
-               if (has_trailing_carriage_return)
-                       len--;
-               nofirst = 0;
+       has_trailing_newline = (len > 0 && line[len-1] == '\n');
+       if (has_trailing_newline)
+               len--;
+
+       has_trailing_carriage_return = (len > 0 && line[len-1] == '\r');
+       if (has_trailing_carriage_return)
+               len--;
+
+       if (!len && !first)
+               goto end_of_line;
+
+       if (reverse && want_color(o->use_color)) {
+               fputs(GIT_COLOR_REVERSE, file);
+               needs_reset = 1;
+       }
+
+       if (set_sign) {
+               fputs(set_sign, file);
+               needs_reset = 1;
        }
 
-       if (len || !nofirst) {
+       if (first)
+               fputc(first, file);
+
+       if (!len)
+               goto end_of_line;
+
+       if (set) {
+               if (set_sign && set != set_sign)
+                       fputs(reset, file);
                fputs(set, file);
-               if (!nofirst)
-                       fputc(first, file);
-               fwrite(line, len, 1, file);
-               fputs(reset, file);
+               needs_reset = 1;
        }
+       fwrite(line, len, 1, file);
+       needs_reset = 1; /* 'line' may contain color codes. */
+
+end_of_line:
+       if (needs_reset)
+               fputs(reset, file);
        if (has_trailing_carriage_return)
                fputc('\r', file);
        if (has_trailing_newline)
@@ -610,7 +681,7 @@ static void emit_line_0(struct diff_options *o, const char *set, const char *res
 static void emit_line(struct diff_options *o, const char *set, const char *reset,
                      const char *line, int len)
 {
-       emit_line_0(o, set, reset, line[0], line+1, len-1);
+       emit_line_0(o, set, NULL, 0, reset, 0, line, len);
 }
 
 enum diff_symbol {
@@ -705,16 +776,116 @@ struct moved_entry {
        struct hashmap_entry ent;
        const struct emitted_diff_symbol *es;
        struct moved_entry *next_line;
+       struct ws_delta *wsd;
 };
 
-static int moved_entry_cmp(const struct diff_options *diffopt,
-                          const struct moved_entry *a,
-                          const struct moved_entry *b,
+/**
+ * The struct ws_delta holds white space differences between moved lines, i.e.
+ * between '+' and '-' lines that have been detected to be a move.
+ * The string contains the difference in leading white spaces, before the
+ * rest of the line is compared using the white space config for move
+ * coloring. The current_longer indicates if the first string in the
+ * comparision is longer than the second.
+ */
+struct ws_delta {
+       char *string;
+       unsigned int current_longer : 1;
+};
+#define WS_DELTA_INIT { NULL, 0 }
+
+static int compute_ws_delta(const struct emitted_diff_symbol *a,
+                            const struct emitted_diff_symbol *b,
+                            struct ws_delta *out)
+{
+       const struct emitted_diff_symbol *longer =  a->len > b->len ? a : b;
+       const struct emitted_diff_symbol *shorter = a->len > b->len ? b : a;
+       int d = longer->len - shorter->len;
+
+       out->string = xmemdupz(longer->line, d);
+       out->current_longer = (a == longer);
+
+       return !strncmp(longer->line + d, shorter->line, shorter->len);
+}
+
+static int cmp_in_block_with_wsd(const struct diff_options *o,
+                                const struct moved_entry *cur,
+                                const struct moved_entry *match,
+                                struct moved_entry *pmb,
+                                int n)
+{
+       struct emitted_diff_symbol *l = &o->emitted_symbols->buf[n];
+       int al = cur->es->len, cl = l->len;
+       const char *a = cur->es->line,
+                  *b = match->es->line,
+                  *c = l->line;
+
+       int wslen;
+
+       /*
+        * We need to check if 'cur' is equal to 'match'.
+        * As those are from the same (+/-) side, we do not need to adjust for
+        * indent changes. However these were found using fuzzy matching
+        * so we do have to check if they are equal.
+        */
+       if (strcmp(a, b))
+               return 1;
+
+       if (!pmb->wsd)
+               /*
+                * No white space delta was carried forward? This can happen
+                * when we exit early in this function and do not carry
+                * forward ws.
+                */
+               return 1;
+
+       /*
+        * The indent changes of the block are known and carried forward in
+        * pmb->wsd; however we need to check if the indent changes of the
+        * current line are still the same as before.
+        *
+        * To do so we need to compare 'l' to 'cur', adjusting the
+        * one of them for the white spaces, depending which was longer.
+        */
+
+       wslen = strlen(pmb->wsd->string);
+       if (pmb->wsd->current_longer) {
+               c += wslen;
+               cl -= wslen;
+       } else {
+               a += wslen;
+               al -= wslen;
+       }
+
+       if (strcmp(a, c))
+               return 1;
+
+       return 0;
+}
+
+static int moved_entry_cmp(const void *hashmap_cmp_fn_data,
+                          const void *entry,
+                          const void *entry_or_key,
                           const void *keydata)
 {
+       const struct diff_options *diffopt = hashmap_cmp_fn_data;
+       const struct moved_entry *a = entry;
+       const struct moved_entry *b = entry_or_key;
+       unsigned flags = diffopt->color_moved_ws_handling
+                        & XDF_WHITESPACE_FLAGS;
+
+       if (diffopt->color_moved_ws_handling &
+           COLOR_MOVED_WS_ALLOW_INDENTATION_CHANGE)
+               /*
+                * As there is not specific white space config given,
+                * we'd need to check for a new block, so ignore all
+                * white space. The setup of the white space
+                * configuration for the next block is done else where
+                */
+               flags |= XDF_IGNORE_WHITESPACE;
+
        return !xdiff_compare_lines(a->es->line, a->es->len,
                                    b->es->line, b->es->len,
-                                   diffopt->xdl_opts);
+                                   flags);
 }
 
 static struct moved_entry *prepare_entry(struct diff_options *o,
@@ -722,10 +893,12 @@ static struct moved_entry *prepare_entry(struct diff_options *o,
 {
        struct moved_entry *ret = xmalloc(sizeof(*ret));
        struct emitted_diff_symbol *l = &o->emitted_symbols->buf[line_no];
+       unsigned flags = o->color_moved_ws_handling & XDF_WHITESPACE_FLAGS;
 
-       ret->ent.hash = xdiff_hash_string(l->line, l->len, o->xdl_opts);
+       ret->ent.hash = xdiff_hash_string(l->line, l->len, flags);
        ret->es = l;
        ret->next_line = NULL;
+       ret->wsd = NULL;
 
        return ret;
 }
@@ -762,6 +935,61 @@ static void add_lines_to_move_detection(struct diff_options *o,
        }
 }
 
+static void pmb_advance_or_null(struct diff_options *o,
+                               struct moved_entry *match,
+                               struct hashmap *hm,
+                               struct moved_entry **pmb,
+                               int pmb_nr)
+{
+       int i;
+       for (i = 0; i < pmb_nr; i++) {
+               struct moved_entry *prev = pmb[i];
+               struct moved_entry *cur = (prev && prev->next_line) ?
+                               prev->next_line : NULL;
+               if (cur && !hm->cmpfn(o, cur, match, NULL)) {
+                       pmb[i] = cur;
+               } else {
+                       pmb[i] = NULL;
+               }
+       }
+}
+
+static void pmb_advance_or_null_multi_match(struct diff_options *o,
+                                           struct moved_entry *match,
+                                           struct hashmap *hm,
+                                           struct moved_entry **pmb,
+                                           int pmb_nr, int n)
+{
+       int i;
+       char *got_match = xcalloc(1, pmb_nr);
+
+       for (; match; match = hashmap_get_next(hm, match)) {
+               for (i = 0; i < pmb_nr; i++) {
+                       struct moved_entry *prev = pmb[i];
+                       struct moved_entry *cur = (prev && prev->next_line) ?
+                                       prev->next_line : NULL;
+                       if (!cur)
+                               continue;
+                       if (!cmp_in_block_with_wsd(o, cur, match, pmb[i], n))
+                               got_match[i] |= 1;
+               }
+       }
+
+       for (i = 0; i < pmb_nr; i++) {
+               if (got_match[i]) {
+                       /* Carry the white space delta forward */
+                       pmb[i]->next_line->wsd = pmb[i]->wsd;
+                       pmb[i] = pmb[i]->next_line;
+               } else {
+                       if (pmb[i]->wsd) {
+                               free(pmb[i]->wsd->string);
+                               FREE_AND_NULL(pmb[i]->wsd);
+                       }
+                       pmb[i] = NULL;
+               }
+       }
+}
+
 static int shrink_potential_moved_blocks(struct moved_entry **pmb,
                                         int pmb_nr)
 {
@@ -836,19 +1064,18 @@ static void mark_color_as_moved(struct diff_options *o,
                struct moved_entry *key;
                struct moved_entry *match = NULL;
                struct emitted_diff_symbol *l = &o->emitted_symbols->buf[n];
-               int i;
 
                switch (l->s) {
                case DIFF_SYMBOL_PLUS:
                        hm = del_lines;
                        key = prepare_entry(o, n);
-                       match = hashmap_get(hm, key, o);
+                       match = hashmap_get(hm, key, NULL);
                        free(key);
                        break;
                case DIFF_SYMBOL_MINUS:
                        hm = add_lines;
                        key = prepare_entry(o, n);
-                       match = hashmap_get(hm, key, o);
+                       match = hashmap_get(hm, key, NULL);
                        free(key);
                        break;
                default:
@@ -867,17 +1094,11 @@ static void mark_color_as_moved(struct diff_options *o,
                if (o->color_moved == COLOR_MOVED_PLAIN)
                        continue;
 
-               /* Check any potential block runs, advance each or nullify */
-               for (i = 0; i < pmb_nr; i++) {
-                       struct moved_entry *p = pmb[i];
-                       struct moved_entry *pnext = (p && p->next_line) ?
-                                       p->next_line : NULL;
-                       if (pnext && !hm->cmpfn(o, pnext, match, NULL)) {
-                               pmb[i] = p->next_line;
-                       } else {
-                               pmb[i] = NULL;
-                       }
-               }
+               if (o->color_moved_ws_handling &
+                   COLOR_MOVED_WS_ALLOW_INDENTATION_CHANGE)
+                       pmb_advance_or_null_multi_match(o, match, hm, pmb, pmb_nr, n);
+               else
+                       pmb_advance_or_null(o, match, hm, pmb, pmb_nr);
 
                pmb_nr = shrink_potential_moved_blocks(pmb, pmb_nr);
 
@@ -888,7 +1109,17 @@ static void mark_color_as_moved(struct diff_options *o,
                         */
                        for (; match; match = hashmap_get_next(hm, match)) {
                                ALLOC_GROW(pmb, pmb_nr + 1, pmb_alloc);
-                               pmb[pmb_nr++] = match;
+                               if (o->color_moved_ws_handling &
+                                   COLOR_MOVED_WS_ALLOW_INDENTATION_CHANGE) {
+                                       struct ws_delta *wsd = xmalloc(sizeof(*match->wsd));
+                                       if (compute_ws_delta(l, match->es, wsd)) {
+                                               match->wsd = wsd;
+                                               pmb[pmb_nr++] = match;
+                                       } else
+                                               free(wsd);
+                               } else {
+                                       pmb[pmb_nr++] = match;
+                               }
                        }
 
                        flipped_block = (flipped_block + 1) % 2;
@@ -899,7 +1130,7 @@ static void mark_color_as_moved(struct diff_options *o,
 
                block_length++;
 
-               if (flipped_block)
+               if (flipped_block && o->color_moved != COLOR_MOVED_BLOCKS)
                        l->flags |= DIFF_SYMBOL_MOVED_LINE_ALT;
        }
        adjust_last_block(o, n, block_length);
@@ -969,8 +1200,9 @@ static void dim_moved_lines(struct diff_options *o)
 }
 
 static void emit_line_ws_markup(struct diff_options *o,
-                               const char *set, const char *reset,
-                               const char *line, int len, char sign,
+                               const char *set_sign, const char *set,
+                               const char *reset,
+                               char sign, const char *line, int len,
                                unsigned ws_rule, int blank_at_eof)
 {
        const char *ws = NULL;
@@ -981,14 +1213,17 @@ static void emit_line_ws_markup(struct diff_options *o,
                        ws = NULL;
        }
 
-       if (!ws)
-               emit_line_0(o, set, reset, sign, line, len);
-       else if (blank_at_eof)
+       if (!ws && !set_sign)
+               emit_line_0(o, set, NULL, 0, reset, sign, line, len);
+       else if (!ws) {
+               emit_line_0(o, set_sign, set, !!set_sign, reset, sign, line, len);
+       } else if (blank_at_eof)
                /* Blank line at EOF - paint '+' as well */
-               emit_line_0(o, ws, reset, sign, line, len);
+               emit_line_0(o, ws, NULL, 0, reset, sign, line, len);
        else {
                /* Emit just the prefix, then the rest. */
-               emit_line_0(o, set, reset, sign, "", 0);
+               emit_line_0(o, set_sign ? set_sign : set, NULL, !!set_sign, reset,
+                           sign, "", 0);
                ws_check_emit(line, len, ws_rule,
                              o->file, set, reset, ws);
        }
@@ -998,7 +1233,7 @@ static void emit_diff_symbol_from_struct(struct diff_options *o,
                                         struct emitted_diff_symbol *eds)
 {
        static const char *nneof = " No newline at end of file\n";
-       const char *context, *reset, *set, *meta, *fraginfo;
+       const char *context, *reset, *set, *set_sign, *meta, *fraginfo;
        struct strbuf sb = STRBUF_INIT;
 
        enum diff_symbol s = eds->s;
@@ -1011,7 +1246,7 @@ static void emit_diff_symbol_from_struct(struct diff_options *o,
                context = diff_get_color_opt(o, DIFF_CONTEXT);
                reset = diff_get_color_opt(o, DIFF_RESET);
                putc('\n', o->file);
-               emit_line_0(o, context, reset, '\\',
+               emit_line_0(o, context, NULL, 0, reset, '\\',
                            nneof, strlen(nneof));
                break;
        case DIFF_SYMBOL_SUBMODULE_HEADER:
@@ -1038,7 +1273,20 @@ static void emit_diff_symbol_from_struct(struct diff_options *o,
        case DIFF_SYMBOL_CONTEXT:
                set = diff_get_color_opt(o, DIFF_CONTEXT);
                reset = diff_get_color_opt(o, DIFF_RESET);
-               emit_line_ws_markup(o, set, reset, line, len, ' ',
+               set_sign = NULL;
+               if (o->flags.dual_color_diffed_diffs) {
+                       char c = !len ? 0 : line[0];
+
+                       if (c == '+')
+                               set = diff_get_color_opt(o, DIFF_FILE_NEW);
+                       else if (c == '@')
+                               set = diff_get_color_opt(o, DIFF_FRAGINFO);
+                       else if (c == '-')
+                               set = diff_get_color_opt(o, DIFF_FILE_OLD);
+               }
+               emit_line_ws_markup(o, set_sign, set, reset,
+                                   o->output_indicators[OUTPUT_INDICATOR_CONTEXT],
+                                   line, len,
                                    flags & (DIFF_SYMBOL_CONTENT_WS_MASK), 0);
                break;
        case DIFF_SYMBOL_PLUS:
@@ -1065,7 +1313,25 @@ static void emit_diff_symbol_from_struct(struct diff_options *o,
                        set = diff_get_color_opt(o, DIFF_FILE_NEW);
                }
                reset = diff_get_color_opt(o, DIFF_RESET);
-               emit_line_ws_markup(o, set, reset, line, len, '+',
+               if (!o->flags.dual_color_diffed_diffs)
+                       set_sign = NULL;
+               else {
+                       char c = !len ? 0 : line[0];
+
+                       set_sign = set;
+                       if (c == '-')
+                               set = diff_get_color_opt(o, DIFF_FILE_OLD_BOLD);
+                       else if (c == '@')
+                               set = diff_get_color_opt(o, DIFF_FRAGINFO);
+                       else if (c == '+')
+                               set = diff_get_color_opt(o, DIFF_FILE_NEW_BOLD);
+                       else
+                               set = diff_get_color_opt(o, DIFF_CONTEXT_BOLD);
+                       flags &= ~DIFF_SYMBOL_CONTENT_WS_MASK;
+               }
+               emit_line_ws_markup(o, set_sign, set, reset,
+                                   o->output_indicators[OUTPUT_INDICATOR_NEW],
+                                   line, len,
                                    flags & DIFF_SYMBOL_CONTENT_WS_MASK,
                                    flags & DIFF_SYMBOL_CONTENT_BLANK_LINE_EOF);
                break;
@@ -1093,7 +1359,24 @@ static void emit_diff_symbol_from_struct(struct diff_options *o,
                        set = diff_get_color_opt(o, DIFF_FILE_OLD);
                }
                reset = diff_get_color_opt(o, DIFF_RESET);
-               emit_line_ws_markup(o, set, reset, line, len, '-',
+               if (!o->flags.dual_color_diffed_diffs)
+                       set_sign = NULL;
+               else {
+                       char c = !len ? 0 : line[0];
+
+                       set_sign = set;
+                       if (c == '+')
+                               set = diff_get_color_opt(o, DIFF_FILE_NEW_DIM);
+                       else if (c == '@')
+                               set = diff_get_color_opt(o, DIFF_FRAGINFO);
+                       else if (c == '-')
+                               set = diff_get_color_opt(o, DIFF_FILE_OLD_DIM);
+                       else
+                               set = diff_get_color_opt(o, DIFF_CONTEXT_DIM);
+               }
+               emit_line_ws_markup(o, set_sign, set, reset,
+                                   o->output_indicators[OUTPUT_INDICATOR_OLD],
+                                   line, len,
                                    flags & DIFF_SYMBOL_CONTENT_WS_MASK, 0);
                break;
        case DIFF_SYMBOL_WORDS_PORCELAIN:
@@ -1184,7 +1467,7 @@ static void emit_diff_symbol_from_struct(struct diff_options *o,
                fputs(o->stat_sep, o->file);
                break;
        default:
-               die("BUG: unknown diff symbol");
+               BUG("unknown diff symbol");
        }
        strbuf_release(&sb);
 }
@@ -1284,6 +1567,7 @@ static void emit_hunk_header(struct emit_callback *ecbdata,
        const char *frag = diff_get_color(ecbdata->color_diff, DIFF_FRAGINFO);
        const char *func = diff_get_color(ecbdata->color_diff, DIFF_FUNCINFO);
        const char *reset = diff_get_color(ecbdata->color_diff, DIFF_RESET);
+       const char *reverse = ecbdata->color_diff ? GIT_COLOR_REVERSE : "";
        static const char atat[2] = { '@', '@' };
        const char *cp, *ep;
        struct strbuf msgbuf = STRBUF_INIT;
@@ -1304,6 +1588,8 @@ static void emit_hunk_header(struct emit_callback *ecbdata,
        ep += 2; /* skip over @@ */
 
        /* The hunk header in fraginfo color */
+       if (ecbdata->opt->flags.dual_color_diffed_diffs)
+               strbuf_addstr(&msgbuf, reverse);
        strbuf_addstr(&msgbuf, frag);
        strbuf_add(&msgbuf, line, ep - line);
        strbuf_addstr(&msgbuf, reset);
@@ -1343,7 +1629,7 @@ static struct diff_tempfile *claim_diff_tempfile(void) {
        for (i = 0; i < ARRAY_SIZE(diff_temp); i++)
                if (!diff_temp[i].name)
                        return diff_temp + i;
-       die("BUG: diff is failing to clean up its tempfiles");
+       BUG("diff is failing to clean up its tempfiles");
 }
 
 static void remove_tempfile(void)
@@ -1871,8 +2157,8 @@ static void init_diff_words_data(struct emit_callback *ecbdata,
                if (regcomp(ecbdata->diff_words->word_regex,
                            o->word_regex,
                            REG_EXTENDED | REG_NEWLINE))
-                       die ("Invalid regular expression: %s",
-                            o->word_regex);
+                       die("invalid regular expression: %s",
+                           o->word_regex);
        }
        for (i = 0; i < ARRAY_SIZE(diff_words_styles); i++) {
                if (o->word_diff == diff_words_styles[i].type) {
@@ -2663,16 +2949,11 @@ static void show_dirstat(struct diff_options *options)
                struct diff_filepair *p = q->queue[i];
                const char *name;
                unsigned long copied, added, damage;
-               int content_changed;
 
                name = p->two->path ? p->two->path : p->one->path;
 
-               if (p->one->oid_valid && p->two->oid_valid)
-                       content_changed = oidcmp(&p->one->oid, &p->two->oid);
-               else
-                       content_changed = 1;
-
-               if (!content_changed) {
+               if (p->one->oid_valid && p->two->oid_valid &&
+                   oideq(&p->one->oid, &p->two->oid)) {
                        /*
                         * The SHA1 has not changed, so pre-/post-content is
                         * identical. We can therefore skip looking at the
@@ -2719,7 +3000,7 @@ static void show_dirstat(struct diff_options *options)
                 * made to the preimage.
                 * If the resulting damage is zero, we know that
                 * diffcore_count_changes() considers the two entries to
-                * be identical, but since content_changed is true, we
+                * be identical, but since the oid changed, we
                 * know that there must have been _some_ kind of change,
                 * so we force all entries to have damage > 0.
                 */
@@ -3134,7 +3415,7 @@ static void builtin_diff(const char *name_a,
                if (!one->data && !two->data &&
                    S_ISREG(one->mode) && S_ISREG(two->mode) &&
                    !o->flags.binary) {
-                       if (!oidcmp(&one->oid, &two->oid)) {
+                       if (oideq(&one->oid, &two->oid)) {
                                if (must_show_header)
                                        emit_diff_symbol(o, DIFF_SYMBOL_HEADER,
                                                         header.buf, header.len,
@@ -3197,13 +3478,16 @@ static void builtin_diff(const char *name_a,
                memset(&xpp, 0, sizeof(xpp));
                memset(&xecfg, 0, sizeof(xecfg));
                memset(&ecbdata, 0, sizeof(ecbdata));
+               if (o->flags.suppress_diff_headers)
+                       lbl[0] = NULL;
                ecbdata.label_path = lbl;
                ecbdata.color_diff = want_color(o->use_color);
                ecbdata.ws_rule = whitespace_rule(name_b);
                if (ecbdata.ws_rule & WS_BLANK_AT_EOF)
                        check_blank_at_eof(&mf1, &mf2, &ecbdata);
                ecbdata.opt = o;
-               ecbdata.header = header.len ? &header : NULL;
+               if (header.len && !o->flags.suppress_diff_headers)
+                       ecbdata.header = &header;
                xpp.flags = o->xdl_opts;
                xpp.anchors = o->anchors;
                xpp.anchors_nr = o->anchors_nr;
@@ -3296,7 +3580,7 @@ static void builtin_diffstat(const char *name_a, const char *name_b,
                return;
        }
 
-       same_contents = !oidcmp(&one->oid, &two->oid);
+       same_contents = oideq(&one->oid, &two->oid);
 
        if (diff_filespec_is_binary(one) || diff_filespec_is_binary(two)) {
                data->is_binary = 1;
@@ -3472,7 +3756,7 @@ static int reuse_worktree_file(const char *name, const struct object_id *oid, in
         * objects however would tend to be slower as they need
         * to be individually opened and inflated.
         */
-       if (!FAST_WORKING_DIRECTORY && !want_file && has_sha1_pack(oid->hash))
+       if (!FAST_WORKING_DIRECTORY && !want_file && has_object_pack(oid))
                return 0;
 
        /*
@@ -3492,7 +3776,7 @@ static int reuse_worktree_file(const char *name, const struct object_id *oid, in
         * This is not the sha1 we are looking for, or
         * unreusable because it is not a regular file.
         */
-       if (oidcmp(oid, &ce->oid) || !S_ISREG(ce->ce_mode))
+       if (!oideq(oid, &ce->oid) || !S_ISREG(ce->ce_mode))
                return 0;
 
        /*
@@ -3638,7 +3922,8 @@ int diff_populate_filespec(struct diff_filespec *s, unsigned int flags)
        else {
                enum object_type type;
                if (size_only || (flags & CHECK_BINARY)) {
-                       type = sha1_object_info(s->oid.hash, &s->size);
+                       type = oid_object_info(the_repository, &s->oid,
+                                              &s->size);
                        if (type < 0)
                                die("unable to read %s",
                                    oid_to_hex(&s->oid));
@@ -3649,7 +3934,7 @@ int diff_populate_filespec(struct diff_filespec *s, unsigned int flags)
                                return 0;
                        }
                }
-               s->data = read_sha1_file(s->oid.hash, &type, &s->size);
+               s->data = read_object_file(&s->oid, &type, &s->size);
                if (!s->data)
                        die("unable to read %s", oid_to_hex(&s->oid));
                s->should_free = 1;
@@ -3694,7 +3979,7 @@ static void prep_temp_blob(const char *path, struct diff_tempfile *temp,
        temp->tempfile = mks_tempfile_ts(tempfile.buf, strlen(base) + 1);
        if (!temp->tempfile)
                die_errno("unable to create temp-file");
-       if (convert_to_working_tree(path,
+       if (convert_to_working_tree(&the_index, path,
                        (const char *)blob, (size_t)size, &buf)) {
                blob = buf.buf;
                size = buf.len;
@@ -3834,13 +4119,13 @@ static int similarity_index(struct diff_filepair *p)
 static const char *diff_abbrev_oid(const struct object_id *oid, int abbrev)
 {
        if (startup_info->have_repository)
-               return find_unique_abbrev(oid->hash, abbrev);
+               return find_unique_abbrev(oid, abbrev);
        else {
                char *hex = oid_to_hex(oid);
                if (abbrev < 0)
                        abbrev = FALLBACK_DEFAULT_ABBREV;
-               if (abbrev > GIT_SHA1_HEXSZ)
-                       die("BUG: oid abbreviation out of range: %d", abbrev);
+               if (abbrev > the_hash_algo->hexsz)
+                       BUG("oid abbreviation out of range: %d", abbrev);
                if (abbrev)
                        hex[abbrev] = '\0';
                return hex;
@@ -3896,14 +4181,15 @@ static void fill_metainfo(struct strbuf *msg,
        default:
                *must_show_header = 0;
        }
-       if (one && two && oidcmp(&one->oid, &two->oid)) {
-               int abbrev = o->flags.full_index ? 40 : DEFAULT_ABBREV;
+       if (one && two && !oideq(&one->oid, &two->oid)) {
+               const unsigned hexsz = the_hash_algo->hexsz;
+               int abbrev = o->flags.full_index ? hexsz : DEFAULT_ABBREV;
 
                if (o->flags.binary) {
                        mmfile_t mf;
                        if ((!fill_mmfile(&mf, one) && diff_filespec_is_binary(one)) ||
                            (!fill_mmfile(&mf, two) && diff_filespec_is_binary(two)))
-                               abbrev = 40;
+                               abbrev = hexsz;
                }
                strbuf_addf(msg, "%s%sindex %s..%s", line_prefix, set,
                            diff_abbrev_oid(&one->oid, abbrev),
@@ -4100,6 +4386,9 @@ void diff_setup(struct diff_options *options)
 
        options->file = stdout;
 
+       options->output_indicators[OUTPUT_INDICATOR_NEW] = '+';
+       options->output_indicators[OUTPUT_INDICATOR_OLD] = '-';
+       options->output_indicators[OUTPUT_INDICATOR_CONTEXT] = ' ';
        options->abbrev = DEFAULT_ABBREV;
        options->line_termination = '\n';
        options->break_opt = -1;
@@ -4130,6 +4419,7 @@ void diff_setup(struct diff_options *options)
        }
 
        options->color_moved = diff_color_moved_default;
+       options->color_moved_ws_handling = diff_color_moved_ws_default;
 }
 
 void diff_setup_done(struct diff_options *options)
@@ -4138,6 +4428,11 @@ void diff_setup_done(struct diff_options *options)
                              DIFF_FORMAT_NAME_STATUS |
                              DIFF_FORMAT_CHECKDIFF |
                              DIFF_FORMAT_NO_OUTPUT;
+       /*
+        * This must be signed because we're comparing against a potentially
+        * negative value.
+        */
+       const int hexsz = the_hash_algo->hexsz;
 
        if (options->set_default)
                options->set_default(options);
@@ -4208,18 +4503,8 @@ void diff_setup_done(struct diff_options *options)
 
        if (options->detect_rename && options->rename_limit < 0)
                options->rename_limit = diff_rename_limit_default;
-       if (options->setup & DIFF_SETUP_USE_CACHE) {
-               if (!active_cache)
-                       /* read-cache does not die even when it fails
-                        * so it is safe for us to do this here.  Also
-                        * it does not smudge active_cache or active_nr
-                        * when it fails, so we do not have to worry about
-                        * cleaning it up ourselves either.
-                        */
-                       read_cache();
-       }
-       if (40 < options->abbrev)
-               options->abbrev = 40; /* full */
+       if (hexsz < options->abbrev)
+               options->abbrev = hexsz; /* full */
 
        /*
         * It does not make sense to show the first hit we happened
@@ -4334,7 +4619,7 @@ static int stat_opt(struct diff_options *options, const char **av)
        int argcount = 1;
 
        if (!skip_prefix(arg, "--stat", &arg))
-               die("BUG: stat option does not begin with --stat: %s", arg);
+               BUG("stat option does not begin with --stat: %s", arg);
        end = (char *)arg;
 
        switch (*arg) {
@@ -4581,6 +4866,12 @@ int diff_opt_parse(struct diff_options *options,
                 options->output_format |= DIFF_FORMAT_DIFFSTAT;
        } else if (!strcmp(arg, "--no-compact-summary"))
                 options->flags.stat_with_summary = 0;
+       else if (skip_prefix(arg, "--output-indicator-new=", &arg))
+               options->output_indicators[OUTPUT_INDICATOR_NEW] = arg[0];
+       else if (skip_prefix(arg, "--output-indicator-old=", &arg))
+               options->output_indicators[OUTPUT_INDICATOR_OLD] = arg[0];
+       else if (skip_prefix(arg, "--output-indicator-context=", &arg))
+               options->output_indicators[OUTPUT_INDICATOR_CONTEXT] = arg[0];
 
        /* renames options */
        else if (starts_with(arg, "-B") ||
@@ -4704,6 +4995,8 @@ int diff_opt_parse(struct diff_options *options,
                if (cm < 0)
                        die("bad --color-moved argument: %s", arg);
                options->color_moved = cm;
+       } else if (skip_prefix(arg, "--color-moved-ws=", &arg)) {
+               options->color_moved_ws_handling = parse_color_moved_ws(arg);
        } else if (skip_to_optional_arg_default(arg, "--color-words", &options->word_regex, NULL)) {
                options->use_color = 1;
                options->word_diff = DIFF_WORDS_COLOR;
@@ -4797,8 +5090,8 @@ int diff_opt_parse(struct diff_options *options,
                options->abbrev = strtoul(arg, NULL, 10);
                if (options->abbrev < MINIMUM_ABBREV)
                        options->abbrev = MINIMUM_ABBREV;
-               else if (40 < options->abbrev)
-                       options->abbrev = 40;
+               else if (the_hash_algo->hexsz < options->abbrev)
+                       options->abbrev = the_hash_algo->hexsz;
        }
        else if ((argcount = parse_long_opt("src-prefix", av, &optarg))) {
                options->a_prefix = optarg;
@@ -4948,7 +5241,7 @@ const char *diff_aligned_abbrev(const struct object_id *oid, int len)
        const char *abbrev;
 
        /* Do we want all 40 hex characters? */
-       if (len == GIT_SHA1_HEXSZ)
+       if (len == the_hash_algo->hexsz)
                return oid_to_hex(oid);
 
        /* An abbreviated value is fine, possibly followed by an ellipsis. */
@@ -4978,7 +5271,7 @@ const char *diff_aligned_abbrev(const struct object_id *oid, int len)
         * the automatic sizing is supposed to give abblen that ensures
         * uniqueness across all objects (statistically speaking).
         */
-       if (abblen < GIT_SHA1_HEXSZ - 3) {
+       if (abblen < the_hash_algo->hexsz - 3) {
                static char hex[GIT_MAX_HEXSZ + 1];
                if (len < abblen && abblen <= len + 2)
                        xsnprintf(hex, sizeof(hex), "%s%.*s", abbrev, len+3-abblen, "..");
@@ -5050,7 +5343,7 @@ int diff_unmodified_pair(struct diff_filepair *p)
         * dealing with a change.
         */
        if (one->oid_valid && two->oid_valid &&
-           !oidcmp(&one->oid, &two->oid) &&
+           oideq(&one->oid, &two->oid) &&
            !one->dirty_submodule && !two->dirty_submodule)
                return 1; /* no change */
        if (!one->oid_valid && !two->oid_valid)
@@ -5184,7 +5477,7 @@ static void diff_resolve_rename_copy(void)
                        else
                                p->status = DIFF_STATUS_RENAMED;
                }
-               else if (oidcmp(&p->one->oid, &p->two->oid) ||
+               else if (!oideq(&p->one->oid, &p->two->oid) ||
                         p->one->mode != p->two->mode ||
                         p->one->dirty_submodule ||
                         p->two->dirty_submodule ||
@@ -5519,7 +5812,7 @@ static void diff_flush_patch_all_file_pairs(struct diff_options *o)
        struct diff_queue_struct *q = &diff_queued_diff;
 
        if (WSEH_NEW & WS_RULE_MASK)
-               die("BUG: WS rules bit mask overlaps with diff symbol flags");
+               BUG("WS rules bit mask overlaps with diff symbol flags");
 
        if (o->color_moved)
                o->emitted_symbols = &esm;
@@ -5534,10 +5827,12 @@ static void diff_flush_patch_all_file_pairs(struct diff_options *o)
                if (o->color_moved) {
                        struct hashmap add_lines, del_lines;
 
-                       hashmap_init(&del_lines,
-                                    (hashmap_cmp_fn)moved_entry_cmp, o, 0);
-                       hashmap_init(&add_lines,
-                                    (hashmap_cmp_fn)moved_entry_cmp, o, 0);
+                       if (o->color_moved_ws_handling &
+                           COLOR_MOVED_WS_ALLOW_INDENTATION_CHANGE)
+                               o->color_moved_ws_handling |= XDF_IGNORE_WHITESPACE;
+
+                       hashmap_init(&del_lines, moved_entry_cmp, o, 0);
+                       hashmap_init(&add_lines, moved_entry_cmp, o, 0);
 
                        add_lines_to_move_detection(o, &add_lines, &del_lines);
                        mark_color_as_moved(o, &add_lines, &del_lines);
@@ -6053,7 +6348,7 @@ size_t fill_textconv(struct userdiff_driver *driver,
        }
 
        if (!driver->textconv)
-               die("BUG: fill_textconv called with non-textconv driver");
+               BUG("fill_textconv called with non-textconv driver");
 
        if (driver->textconv_cache && df->oid_valid) {
                *outbuf = notes_cache_get(driver->textconv_cache,