Subject: Re: [PATCH 2/2] diff: add 'diff.wordDiff' config option

From: Jean-Noël AVILA <[email-masked]>
Date: Sat, 02 Mar 2024 20:57:48 +0100

Hello,

On Saturday, 2 March 2024 10:57:51 CET Karthik Nayak wrote:
> The git-diff(1) command supports the `--word-diff` which allows the
> users to specify how to delimit word diffs. Provide this option also as
> a config param 'diff.wordDiff'.
> 
> Signed-off-by: Karthik Nayak <[email-masked]>
> ---
>  Documentation/config/diff.txt |  4 +++
>  diff.c                        | 50 +++++++++++++++++++++++++++--------
>  t/t4034-diff-words.sh         | 11 ++++++--
>  3 files changed, 52 insertions(+), 13 deletions(-)
> 
> diff --git a/Documentation/config/diff.txt b/Documentation/config/diff.txt
> index bd5ae0c337..00459beee2 100644
> --- a/Documentation/config/diff.txt
> +++ b/Documentation/config/diff.txt
> @@ -225,3 +225,7 @@ diff.colorMovedWS::
>  	When moved lines are colored using e.g. the `diff.colorMoved` 
setting,
>  	this option controls the `<mode>` how spaces are treated
>  	for details of valid modes see '--color-moved-ws' in linkgit:git-
diff[1].
> +
> +diff.wordDiff::
> +	Show a word diff, using the `<mode>` to delimit changed words.
> +	For details of valid modes see '--word-diff' in linkgit:git-diff[1].

Let's enforce the new formatting rules: placeholders are _emphasized_  and 
options are `verbatim`

+
 +diff.wordDiff::
 +	Show a word diff, using the _<mode>_ to delimit changed words.
 +	For details of valid modes see `--word-diff` in linkgit:git-diff[1].

> diff --git a/diff.c b/diff.c
> index e50def4538..050d83ef85 100644
> --- a/diff.c
> +++ b/diff.c
> @@ -69,6 +69,7 @@ static int diff_dirstat_permille_default = 30;
>  static struct diff_options default_diff_options;
>  static long diff_algorithm;
>  static unsigned ws_error_highlight_default = WSEH_NEW;
> +static int diff_word_diff_default;
>  
>  static char diff_colors[][COLOR_MAXLEN] = {
>  	GIT_COLOR_RESET,
> @@ -209,6 +210,23 @@ int git_config_rename(const char *var, const char 
*value)
>  	return git_config_bool(var,value) ? DIFF_DETECT_RENAME : 0;
>  }
>  
> +static int parse_word_diff_value(const char *value)
> +{
> +	if (!value)
> +		return -1;
> +	else if (!strcmp(value, "plain"))
> +		return DIFF_WORDS_PLAIN;
> +	else if (!strcmp(value, "color")) {
> +		return DIFF_WORDS_COLOR;
> +	}
> +	else if (!strcmp(value, "porcelain"))
> +		return DIFF_WORDS_PORCELAIN;
> +	else if (!strcmp(value, "none"))
> +		return DIFF_WORDS_NONE;
> +
> +	return -1;
> +}
> +
>  long parse_algorithm_value(const char *value)
>  {
>  	if (!value)
> @@ -452,6 +470,18 @@ int git_diff_ui_config(const char *var, const char 
*value,
>  		return 0;
>  	}
>  
> +	if (!strcmp(var, "diff.worddiff")) {
> +		if (!value)
> +			return config_error_nonbool(var);
> +		diff_word_diff_default = parse_word_diff_value(value);
> +		if (diff_word_diff_default < 0)
> +			return error(_("unknown value for config '%s': 
%s"),

Thanks for reusing already an already existing translatable string.

> +				     var, value);
> +		if (diff_word_diff_default == DIFF_WORDS_COLOR)
> +			diff_use_color_default = 1;
> +		return 0;
> +	}
> +
>  	if (git_color_config(var, value, cb) < 0)
>  		return -1;
>  
> @@ -4724,6 +4754,7 @@ void repo_diff_setup(struct repository *r, struct 
diff_options *options)
>  	options->use_color = diff_use_color_default;
>  	options->detect_rename = diff_detect_rename_default;
>  	options->xdl_opts |= diff_algorithm;
> +	options->word_diff |= diff_word_diff_default;
>  	if (diff_indent_heuristic)
>  		DIFF_XDL_SET(options, INDENT_HEURISTIC);
>  
> @@ -5504,21 +5535,18 @@ static int diff_opt_word_diff(const struct option 
*opt,
>  			      const char *arg, int unset)
>  {
>  	struct diff_options *options = opt->value;
> +	int value;
>  
>  	BUG_ON_OPT_NEG(unset);
> +
>  	if (arg) {
> -		if (!strcmp(arg, "plain"))
> -			options->word_diff = DIFF_WORDS_PLAIN;
> -		else if (!strcmp(arg, "color")) {
> -			options->use_color = 1;
> -			options->word_diff = DIFF_WORDS_COLOR;
> -		}
> -		else if (!strcmp(arg, "porcelain"))
> -			options->word_diff = DIFF_WORDS_PORCELAIN;
> -		else if (!strcmp(arg, "none"))
> -			options->word_diff = DIFF_WORDS_NONE;
> -		else
> +		value = parse_word_diff_value(arg);
> +		if (value < 0)
>  			return error(_("bad --word-diff argument: 
%s"), arg);
> +		if (value == DIFF_WORDS_COLOR)
> +			options->use_color = 1;
> +
> +		options->word_diff = value;
>  	} else {
>  		if (options->word_diff == DIFF_WORDS_NONE)
>  			options->word_diff = DIFF_WORDS_PLAIN;
> diff --git a/t/t4034-diff-words.sh b/t/t4034-diff-words.sh
> index 4f70aa6e9f..2cc391c339 100755
> --- a/t/t4034-diff-words.sh
> +++ b/t/t4034-diff-words.sh
> @@ -56,12 +56,19 @@ diff_with_opts () {
>  	post=$(git rev-parse --short $(git hash-object post)) &&
>  	test_must_fail git diff --no-index "$@" pre post >output &&
>  	test_decode_color <output >output.decrypted &&
> -	sed -e "2s/index [^ ]*/index $pre..$post/" expect >expected
> +	sed -e "2s/index [^ ]*/index $pre..$post/" expect >expected &&
>  	test_cmp expected output.decrypted
>  }
>  
>  word_diff () {
> -	diff_with_opts "--word-diff=$1" $(echo "$@" | cut -d' ' -s -f 2-)
> +	# Capture the rest of the arguments to passthrough.
> +	rest=$(echo "$@" | cut -d' ' -s -f 2-) &&
> +	# Test via the config route.
> +	git config diff.wordDiff $1 &&
> +	diff_with_opts $rest &&
> +	git config --unset diff.wordDiff &&
> +	# Test via the command option route.
> +	diff_with_opts "--word-diff=$1" $rest
>  }
>  
>  test_language_driver () {
> 

Thanks