Re: [PATCH 19/19] diff.c: color moved lines differently
- From
- Jonathan Tan <jonathantanmy@google.com>
- Date
- May 16, 2017, 04:34 UTC
- Message-ID
- <CAGf8dgLuJLn=X4gmVGQ0tfTo2=py4XhBw-WSYtw2acy9x3NSJQ@mail.gmail.com>
- In-Reply-To
- <20170514040117.25865-20-sbeller@google.com>
I expected there to be one main function that takes in a diff options and returns the appropriate output without much (if any) changes in other functions...but (as with the previous patch) maybe there are some complications that I didn't foresee.
On Sat, May 13, 2017 at 9:01 PM, Stefan Beller <sbeller@google.com> wrote:
Show 26 quoted lines
> diff --git a/Documentation/config.txt b/Documentation/config.txt
> index 475e874d51..90403c06e3 100644
> --- a/Documentation/config.txt
> +++ b/Documentation/config.txt
> @@ -1051,14 +1051,22 @@ This does not affect linkgit:git-format-patch[1] or the
> 'git-diff-{asterisk}' plumbing commands. Can be overridden on the
> command line with the `--color[=<when>]` option.
>
> +color.moved::
> + A boolean value, whether a diff should color moved lines
> + differently. The moved lines are searched for in the diff only.
> + Duplicated lines from somewhere in the project that are not
> + part of the diff are not colored as moved.
> + Defaults to false.
> +
> color.diff.<slot>::
> Use customized color for diff colorization. `<slot>` specifies
> which part of the patch to use the specified color, and is one
> of `context` (context text - `plain` is a historical synonym),
> `meta` (metainformation), `frag`
> (hunk header), 'func' (function in hunk header), `old` (removed lines),
> - `new` (added lines), `commit` (commit headers), or `whitespace`
> - (highlighting whitespace errors).
> + `new` (added lines), `commit` (commit headers), `whitespace`
> + (highlighting whitespace errors), `movedFrom` (removed lines that
> + reappear), `movedTo` (added lines that were removed elsewhere).There should be 4 "moved" colors. I think the code below is correct (oldmoved, oldmovedalternate, etc.) but the documentation above is wrong.
Show 231 quoted lines
>
> color.decorate.<slot>::
> Use customized color for 'git log --decorate' output. `<slot>` is one
> diff --git a/diff.c b/diff.c
> index dbab7fb44e..6372e0eb25 100644
> --- a/diff.c
> +++ b/diff.c
> @@ -31,6 +31,7 @@ static int diff_indent_heuristic; /* experimental */
> 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_context_default = 3;
> static int diff_interhunk_context_default;
> static const char *diff_word_regex_cfg;
> @@ -55,6 +56,10 @@ static char diff_colors[][COLOR_MAXLEN] = {
> GIT_COLOR_YELLOW, /* COMMIT */
> GIT_COLOR_BG_RED, /* WHITESPACE */
> GIT_COLOR_NORMAL, /* FUNCINFO */
> + GIT_COLOR_BOLD_RED, /* OLD_MOVED_A */
> + GIT_COLOR_BG_RED, /* OLD_MOVED_B */
> + GIT_COLOR_BOLD_GREEN, /* NEW_MOVED_A */
> + GIT_COLOR_BG_GREEN, /* NEW_MOVED_B */
> };
>
> static NORETURN void die_want_option(const char *option_name)
> @@ -80,6 +85,14 @@ static int parse_diff_color_slot(const char *var)
> 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, "newmoved"))
> + return DIFF_FILE_NEW_MOVED;
> + if (!strcasecmp(var, "newmovedalternative"))
> + return DIFF_FILE_NEW_MOVED_ALT;
> return -1;
> }
>
> @@ -234,6 +247,10 @@ int git_diff_ui_config(const char *var, const char *value, void *cb)
> diff_use_color_default = git_config_colorbool(var, value);
> return 0;
> }
> + if (!strcmp(var, "color.moved")) {
> + diff_color_moved_default = git_config_bool(var, value);
> + return 0;
> + }
> if (!strcmp(var, "diff.context")) {
> diff_context_default = git_config_int(var, value);
> if (diff_context_default < 0)
> @@ -354,6 +371,81 @@ int git_diff_basic_config(const char *var, const char *value, void *cb)
> return git_default_config(var, value, cb);
> }
>
> +struct moved_entry {
> + struct hashmap_entry ent;
> + const struct buffered_patch_line *line;
> + struct moved_entry *next_line;
> +};
> +
> +static void get_ws_cleaned_string(const struct buffered_patch_line *l,
> + struct strbuf *out)
> +{
> + int i;
> + for (i = 0; i < l->len; i++) {
> + if (isspace(l->line[i]))
> + continue;
> + strbuf_addch(out, l->line[i]);
> + }
> +}
> +
> +static int buffered_patch_line_cmp_no_ws(const struct buffered_patch_line *a,
> + const struct buffered_patch_line *b,
> + const void *keydata)
> +{
> + struct strbuf sba = STRBUF_INIT;
> + struct strbuf sbb = STRBUF_INIT;
> + get_ws_cleaned_string(a, &sba);
> + get_ws_cleaned_string(b, &sbb);
> + return sba.len != sbb.len || strncmp(sba.buf, sbb.buf, sba.len);
> +}
> +
> +static int buffered_patch_line_cmp(const struct buffered_patch_line *a,
> + const struct buffered_patch_line *b,
> + const void *keydata)
> +{
> + return a->len != b->len || strncmp(a->line, b->line, a->len);
> +}
> +
> +static int moved_entry_cmp(const struct moved_entry *a,
> + const struct moved_entry *b,
> + const void *keydata)
> +{
> + return buffered_patch_line_cmp(a->line, b->line, keydata);
> +}
> +
> +static int moved_entry_cmp_no_ws(const struct moved_entry *a,
> + const struct moved_entry *b,
> + const void *keydata)
> +{
> + return buffered_patch_line_cmp_no_ws(a->line, b->line, keydata);
> +}
> +
> +static unsigned get_line_hash(struct buffered_patch_line *line, unsigned ignore_ws)
> +{
> + static struct strbuf sb = STRBUF_INIT;
> +
> + if (ignore_ws) {
> + strbuf_reset(&sb);
> + get_ws_cleaned_string(line, &sb);
> + return memhash(sb.buf, sb.len);
> + } else
> + return memhash(line->line, line->len);
> +}
> +
> +static struct moved_entry *prepare_entry(struct diff_options *o,
> + int line_no)
> +{
> + struct moved_entry *ret = xmalloc(sizeof(*ret));
> + unsigned ignore_ws = DIFF_XDL_TST(o, IGNORE_WHITESPACE);
> + struct buffered_patch_line *l = &o->line_buffer[line_no];
> +
> + ret->ent.hash = get_line_hash(l, ignore_ws);
> + ret->line = l;
> + ret->next_line = NULL;
> +
> + return ret;
> +}
> +
> static char *quote_two(const char *one, const char *two)
> {
> int need_one = quote_c_style(one, NULL, NULL, 1);
> @@ -516,8 +608,98 @@ static void check_blank_at_eof(mmfile_t *mf1, mmfile_t *mf2,
> ecbdata->blank_at_eof_in_postimage = (at - l2) + 1;
> }
>
> +static void mark_color_as_moved(struct diff_options *o, int line_no)
> +{
> + struct hashmap *hm = NULL;
> + struct moved_entry *key = prepare_entry(o, line_no);
> + struct moved_entry *match = NULL;
> + struct buffered_patch_line *l = &o->line_buffer[line_no];
> + int alt_flag;
> + int i, lp, rp;
> +
> + switch (l->sign) {
> + case '+':
> + hm = o->deleted_lines;
> + break;
> + case '-':
> + hm = o->added_lines;
> + break;
> + default:
> + /* reset to standard, on-alt move color */
> + o->color_moved = 1;
> + break;
> + }
> +
> + /* Check for any match to color it as a move. */
> + if (!hm)
> + return;
> + match = hashmap_get(hm, key, o);
> + free(key);
> + if (!match)
> + return;
> +
> + /* Check any potential block runs, advance each or nullify */
> + for (i = 0; i < o->pmb_nr; i++) {
> + struct moved_entry *p = o->pmb[i];
> + if (p && p->next_line &&
> + !buffered_patch_line_cmp(p->next_line->line, l, o)) {
> + o->pmb[i] = p->next_line;
> + } else {
> + o->pmb[i] = NULL;
> + }
> + }
> +
> + /* Shrink the set to the remaining runs */
> + for (lp = 0, rp = o->pmb_nr - 1; lp <= rp;) {
> + while (lp < o->pmb_nr && o->pmb[lp])
> + lp ++;
> + /* lp points at the first NULL now */
> +
> + while (rp > -1 && !o->pmb[rp])
> + rp--;
> + /* rp points at the last non-NULL */
> +
> + if (lp < o->pmb_nr && rp > -1 && lp < rp) {
> + o->pmb[lp] = o->pmb[rp];
> + o->pmb[rp] = NULL;
> + rp--;
> + lp++;
> + }
> + }
> +
> + if (rp > -1) {
> + /* Remember the number of running sets */
> + o->pmb_nr = rp + 1;
> + } else {
> + /* Toggle color */
> + o->color_moved = o->color_moved == 2 ? 1 : 2;
> +
> + /* Build up a new set */
> + i = 0;
> + for (; match; match = hashmap_get_next(hm, match)) {
> + ALLOC_GROW(o->pmb, i + 1, o->pmb_alloc);
> + o->pmb[i] = match;
> + i++;
> + }
> + o->pmb_nr = i;
> + }
> +
> + alt_flag = o->color_moved - 1;
> + switch (l->sign) {
> + case '+':
> + l->set = diff_get_color_opt(o, DIFF_FILE_NEW_MOVED + alt_flag);
> + break;
> + case '-':
> + l->set = diff_get_color_opt(o, DIFF_FILE_OLD_MOVED + alt_flag);
> + break;
> + default:
> + ; /* nothing */
> + }
> +}
> +
> static void emit_buffered_patch_line(struct diff_options *o,
> - struct buffered_patch_line *e)
> + struct buffered_patch_line *e,
> + int pass)1. I didn't expect such a function to need to be modified in this patch. 2. What does "pass" do?
Show 204 quoted lines
> {
> int has_trailing_newline, has_trailing_carriage_return, len = e->len;
> FILE *file = o->file;
> @@ -548,11 +730,11 @@ static void emit_buffered_patch_line(struct diff_options *o,
>
> static void emit_buffered_patch_line_ws(struct diff_options *o,
> struct buffered_patch_line *e,
> - const char *ws, unsigned ws_rule)
> + const char *ws, unsigned ws_rule,
> + int pass)
> {
> struct buffered_patch_line s = {e->set, e->reset, "", 0, e->sign};
> -
> - emit_buffered_patch_line(o, &s);
> + emit_buffered_patch_line(o, &s, 0);
> ws_check_emit(e->line, e->len, ws_rule,
> o->file, e->set, e->reset, ws);
> }
> @@ -564,12 +746,14 @@ static void process_next_buffered_patch_line(struct diff_options *o, int line_no
> const char *ws = o->current_filepair->ws;
> unsigned ws_rule = o->current_filepair->ws_rule;
>
> + mark_color_as_moved(o, line_no);
> +
> switch (e->state) {
> case BPL_EMIT_LINE_ASIS:
> - emit_buffered_patch_line(o, e);
> + emit_buffered_patch_line(o, e, 1);
> break;
> case BPL_EMIT_LINE_WS:
> - emit_buffered_patch_line_ws(o, e, ws, ws_rule);
> + emit_buffered_patch_line_ws(o, e, ws, ws_rule, 1);
> break;
> case BPL_HANDOVER:
> o->current_filepair++;
> @@ -602,7 +786,7 @@ static void emit_line_0(struct diff_options *o,
> if (o->use_buffer)
> append_buffered_patch_line(o, &e);
> else
> - emit_buffered_patch_line(o, &e);
> + emit_buffered_patch_line(o, &e, 0);
> }
>
> void emit_line(struct diff_options *o, const char *set, const char *reset,
> @@ -621,7 +805,7 @@ static void emit_line_ws(struct diff_options *o,
> if (o->use_buffer)
> append_buffered_patch_line(o, &e);
> else
> - emit_buffered_patch_line_ws(o, &e, ws, ws_rule);
> + emit_buffered_patch_line_ws(o, &e, ws, ws_rule, 0);
> }
>
> void emit_line_fmt(struct diff_options *o,
> @@ -676,6 +860,36 @@ static void emit_line_checked(const char *reset,
> ws, ecbdata->ws_rule);
> }
>
> +static void add_line_to_move_detection(struct diff_options *o, int line_idx)
> +{
> + int sign = 0;
> + struct hashmap *hm;
> + struct moved_entry *key;
> +
> + switch (o->line_buffer[line_idx].sign) {
> + case '+':
> + sign = '+';
> + hm = o->added_lines;
> + break;
> + case '-':
> + sign = '-';
> + hm = o->deleted_lines;
> + break;
> + case ' ':
> + default:
> + o->prev_line = NULL;
> + return;
> + }
> +
> + key = prepare_entry(o, line_idx);
> + if (o->prev_line &&
> + o->prev_line->line->sign == sign)
> + o->prev_line->next_line = key;
> +
> + hashmap_add(hm, key);
> + o->prev_line = key;
> +}
> +
> static void emit_add_line(const char *reset,
> struct emit_callback *ecbdata,
> const char *line, int len)
> @@ -3649,6 +3863,9 @@ void diff_setup_done(struct diff_options *options)
>
> if (DIFF_OPT_TST(options, FOLLOW_RENAMES) && options->pathspec.nr != 1)
> die(_("--follow requires exactly one pathspec"));
> +
> + if (!options->use_color || external_diff())
> + options->color_moved = 0;
> }
>
> static int opt_arg(const char *arg, int arg_short, const char *arg_long, int *val)
> @@ -4073,6 +4290,10 @@ int diff_opt_parse(struct diff_options *options,
> }
> else if (!strcmp(arg, "--no-color"))
> options->use_color = 0;
> + else if (!strcmp(arg, "--color-moved"))
> + options->color_moved = 1;
> + else if (!strcmp(arg, "--no-color-moved"))
> + options->color_moved = 0;
> else if (!strcmp(arg, "--color-words")) {
> options->use_color = 1;
> options->word_diff = DIFF_WORDS_COLOR;
> @@ -4878,16 +5099,19 @@ static void diff_flush_patch_all_file_pairs(struct diff_options *o)
> {
> int i;
> struct diff_queue_struct *q = &diff_queued_diff;
> - /*
> - * For testing purposes we want to make sure the diff machinery
> - * works completely with the buffer. If there is anything emitted
> - * outside the emit_buffered_patch_line, then the order is screwed
> - * up and the tests will fail.
> - *
> - * TODO (later in this series):
> - * We'll unset this flag in a later patch.
> - */
> - o->use_buffer = 1;
> +
> + if (o->color_moved) {
> + unsigned ignore_ws = DIFF_XDL_TST(o, IGNORE_WHITESPACE);
> + o->use_buffer = 1;
> + o->deleted_lines = xmallocz(sizeof(*o->deleted_lines));
> + o->added_lines = xmallocz(sizeof(*o->added_lines));
> + hashmap_init(o->deleted_lines, ignore_ws ?
> + (hashmap_cmp_fn)moved_entry_cmp_no_ws :
> + (hashmap_cmp_fn)moved_entry_cmp, 0);
> + hashmap_init(o->added_lines, ignore_ws ?
> + (hashmap_cmp_fn)moved_entry_cmp_no_ws :
> + (hashmap_cmp_fn)moved_entry_cmp, 0);
> + }
>
> if (o->use_buffer) {
> ALLOC_GROW(o->filepair_buffer,
> @@ -4902,6 +5126,10 @@ static void diff_flush_patch_all_file_pairs(struct diff_options *o)
> }
>
> if (o->use_buffer) {
> + o->current_filepair = &o->filepair_buffer[0];
> + for (i = 0; i < o->line_buffer_nr; i++)
> + add_line_to_move_detection(o, i);
> +
> o->current_filepair = &o->filepair_buffer[0];
> for (i = 0; i < o->line_buffer_nr; i++)
> process_next_buffered_patch_line(o, i);
> @@ -4992,6 +5220,7 @@ void diff_flush(struct diff_options *options)
> if (!options->file)
> die_errno("Could not open /dev/null");
> options->close_file = 1;
> + options->color_moved = 0;
> for (i = 0; i < q->nr; i++) {
> struct diff_filepair *p = q->queue[i];
> if (check_pair_status(p))
> diff --git a/diff.h b/diff.h
> index c334aac02e..b83d6fefcc 100644
> --- a/diff.h
> +++ b/diff.h
> @@ -7,6 +7,7 @@
> #include "tree-walk.h"
> #include "pathspec.h"
> #include "object.h"
> +#include "hashmap.h"
>
> struct rev_info;
> struct diff_options;
> @@ -145,6 +146,8 @@ struct buffered_filepair {
> unsigned ws_rule;
> };
>
> +struct moved_entry;
> +
> struct diff_options {
> const char *orderfile;
> const char *pickaxe;
> @@ -217,6 +220,8 @@ struct diff_options {
>
> int diff_path_counter;
>
> + /* Determines color moved code. Flipped between 1, 2 for alt. color. */
> + int color_moved;
> int use_buffer;
>
> struct buffered_patch_line *line_buffer;
> @@ -225,6 +230,16 @@ struct diff_options {
> struct buffered_filepair *filepair_buffer;
> int filepair_buffer_nr, filepair_buffer_alloc;
> struct buffered_filepair *current_filepair;
> +
> + /* built up in the first pass: */
> + struct hashmap *deleted_lines;
> + struct hashmap *added_lines;
> + /* needed for building up */
> + struct moved_entry *prev_line;
> +
> + /* state in the second pass */
> + struct moved_entry **pmb; /* potentially moved blocks */
> + int pmb_nr, pmb_alloc;Placing these in the public API makes the scope unnecessarily large - could these be stored in a struct (or better, in local variables) private to the .c file? In particular, prev_line should not need a scope greater than a function - a function could just loop through all the buffered lines and construct the two hash maps, and prev_line would not be needed elsewhere.
Show 20 quoted lines
> };
>
> void emit_line_fmt(struct diff_options *o, const char *set, const char *reset,
> @@ -241,7 +256,11 @@ enum color_diff {
> DIFF_FILE_NEW = 5,
> DIFF_COMMIT = 6,
> DIFF_WHITESPACE = 7,
> - DIFF_FUNCINFO = 8
> + DIFF_FUNCINFO = 8,
> + DIFF_FILE_OLD_MOVED = 9,
> + DIFF_FILE_OLD_MOVED_ALT = 10,
> + DIFF_FILE_NEW_MOVED = 11,
> + DIFF_FILE_NEW_MOVED_ALT = 12
> };
> const char *diff_get_color(int diff_use_color, enum color_diff ix);
> #define diff_get_color_opt(o, ix) \
> diff --git a/t/t4015-diff-whitespace.sh b/t/t4015-diff-whitespace.sh
> index 289806d0c7..232d9ad55e 100755
> --- a/t/t4015-diff-whitespace.sh
> +++ b/t/t4015-diff-whitespace.sh[snip]