Re: [PATCH v5 2/2] sideband: highlight keywords in remote sideband output

> The highlighting is done on the client rather than server side, so
> servers don't have to grow capabilities to understand terminal escape
> codes and terminal state. It also consistent with the current state
> where Git is control of the local display (eg. prefixing messages with
> "remote: ").

> +color.remote::
> +	If set, keywords at the start of the line are highlighted. The
> +	keywords are "error", "warning", "hint" and "success", and are
> +	matched case-insensitively. Maybe set to `always`, `false` (or
> +	`never`) or `auto` (or `true`). If unset, then the value of
> +	`color.ui` is used (`auto` by default).

> diff --git a/help.h b/help.h
> index f8b15323a6..9eab6a3f89 100644
> --- a/help.h
> +++ b/help.h
> @@ -83,6 +83,7 @@ void list_config_color_diff_slots(struct string_list *list, const char *prefix);
>  void list_config_color_grep_slots(struct string_list *list, const char *prefix);
>  void list_config_color_interactive_slots(struct string_list *list, const char *prefix);
>  void list_config_color_status_slots(struct string_list *list, const char *prefix);
> +void list_config_color_sideband_slots(struct string_list *list, const char *prefix);
>  void list_config_fsck_msg_ids(struct string_list *list, const char *prefix);
>  
>  #endif /* HELP_H */
> diff --git a/sideband.c b/sideband.c
> index 325bf0e974..239be2ec85 100644
> --- a/sideband.c
> +++ b/sideband.c
> @@ -1,6 +1,108 @@
>  #include "cache.h"
> +#include "color.h"
> +#include "config.h"
>  #include "pkt-line.h"
>  #include "sideband.h"
> +#include "help.h"
> +
> +struct keyword_entry {
> +	/*
> +	 * We use keyword as config key so it should be a single alphanumeric word.
> +	 */
> +	const char *keyword;
> +	char color[COLOR_MAXLEN];
> +};
> +
> +static struct keyword_entry keywords[] = {
> +	{ "hint",	GIT_COLOR_YELLOW },
> +	{ "warning",	GIT_COLOR_BOLD_YELLOW },
> +	{ "success",	GIT_COLOR_BOLD_GREEN },
> +	{ "error",	GIT_COLOR_BOLD_RED },
> +};
> +/* Returns a color setting (GIT_COLOR_NEVER, etc). */
> +static int use_sideband_colors(void)
> +{
> +	static int use_sideband_colors_cached = -1;
> +
> +	const char *key = "color.remote";
> +	struct strbuf sb = STRBUF_INIT;
> +	char *value;
> +	int i;
> +
> +	if (use_sideband_colors_cached >= 0)
> +		return use_sideband_colors_cached;
> +
> +	if (!git_config_get_string(key, &value)) {
> +		use_sideband_colors_cached = git_config_colorbool(key, value);
> +	} else if (!git_config_get_string("color.ui", &value)) {
> +		use_sideband_colors_cached = git_config_colorbool("color.ui", value);
> +	} else {
> +		use_sideband_colors_cached = GIT_COLOR_AUTO;
> +	}
> +
> +	for (i = 0; i < ARRAY_SIZE(keywords); i++) {
> +		strbuf_reset(&sb);
> +		strbuf_addf(&sb, "%s.%s", key, keywords[i].keyword);

> +/*
> + * Optionally highlight one keyword in remote output if it appears at the start
> + * of the line. This should be called for a single line only, which must be
> + * passed as the first N characters of the SRC array.
> + */

> +static void maybe_colorize_sideband(struct strbuf *dest, const char *src, int n)
> +{
> +	int i;
> +
> +	if (!want_color_stderr(use_sideband_colors())) {
> +		strbuf_add(dest, src, n);
> +		return;
> +	}
> +
> +	while (isspace(*src)) {
> +		strbuf_addch(dest, *src);
> +		src++;
> +		n--;
> +	}
> +
> +	for (i = 0; i < ARRAY_SIZE(keywords); i++) {
> +		struct keyword_entry *p = keywords + i;
> +		int len = strlen(p->keyword);
> +		/*
> +		 * Match case insensitively, so we colorize output from existing
> +		 * servers regardless of the case that they use for their
> +		 * messages. We only highlight the word precisely, so
> +		 * "successful" stays uncolored.
> +		 */
> +		if (!strncasecmp(p->keyword, src, len) && !isalnum(src[len])) {
> +			strbuf_addstr(dest, p->color);
> +			strbuf_add(dest, src, len);
> +			strbuf_addstr(dest, GIT_COLOR_RESET);
> +			n -= len;
> +			src += len;
> +			break;
> +		}
> +	}
> +
> +	strbuf_add(dest, src, n);
> +}
> +
>  
>  /*
>   * Receive multiplexed output stream over git native protocol.
> @@ -16,7 +118,7 @@
>  #define DISPLAY_PREFIX "remote: "
>  
>  #define ANSI_SUFFIX "\033[K"
> -#define DUMB_SUFFIX "        "
> +#define DUMB_SUFFIX "	     "
>  

> diff --git a/t/t5409-colorize-remote-messages.sh b/t/t5409-colorize-remote-messages.sh
> new file mode 100755
> index 0000000000..a9afb55ef1
> --- /dev/null
> +++ b/t/t5409-colorize-remote-messages.sh
> @@ -0,0 +1,80 @@
> +#!/bin/sh
> +
> +test_description='remote messages are colorized on the client'
> +
> +. ./test-lib.sh
> +
> +test_expect_success 'setup' '
> +	mkdir .git/hooks &&
> +	write_script .git/hooks/update <<-\EOF &&
> +echo error: error
> +echo ERROR: also highlighted
> +echo hint: hint
> +echo hinting: not highlighted
> +echo success: success
> +echo warning: warning
> +echo prefixerror: error
> +echo "  error: leading space"
> +exit 0
> +EOF