Subject: Re: [PATCH v2 2/2] builtin/repo: fix table alignment for UTF-8 characters

From: Phillip Wood <[email-masked]>
Date: Sat, 15 Nov 2025 15:04:11 +0000

Hi Jiang

On 15/11/2025 13:36, Jiang Xin wrote:
> The output table from "git repo structure" is misaligned when displaying
> UTF-8 characters (e.g., non-ASCII glyphs). E.g.:
> 
>      | 仓库结构   | 值  |
>      | -------------- | ---- |
>      | * 引用       |      |
>      |   * 计数     |   67 |
> 
> The previous implementation used simple width formatting with printf()
> which didn't properly handle multi-byte UTF-8 characters, causing
> misaligned table columns when displaying repository structure
> information.
> 
> This change modifies the stats_table_print_structure function to use
> strbuf_utf8_align() instead of basic printf width specifiers. This
> ensures proper column alignment regardless of the character encoding of
> the content being displayed.

How does it ensure proper column alignment for non-utf8 encodings? I
don't see how it is possible to calculate the display width without
knowing the encoding.
> Also add test cases for strbuf_utf8_align(), a function newly introduced
> in "builtin/repo.c".

Nice.

Using strbuf_utf8_align ends up being quite verbose. An alternative
would be to keep using printf() but calculate the padding ourselves as
shown below. Either way we end up calling utf8_strwidth() twice on the
same string which is a bit of a shame but probably doesn't matter too
much in the grand scheme of things.

Thanks

Phillip

---- 8< ----

  builtin/repo.c | 10 ++++++----
  1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/builtin/repo.c b/builtin/repo.c
index 9d4749f79be..1b139b89672 100644
--- a/builtin/repo.c
+++ b/builtin/repo.c
@@ -298,8 +298,9 @@ static void stats_table_print_structure(const struct stats_table *table)
  	if (table->value_col_width > value_col_width)
  		value_col_width = table->value_col_width;
  
-	printf("| %-*s | %-*s |\n", name_col_width, name_col_title,
-	       value_col_width, value_col_title);
+	printf("| %s%*s | %s%*s |\n",
+	       name_col_title, name_col_width - utf8_strwidth(name_col_title), "",
+	       value_col_title, value_col_width - utf8_strwidth(value_col_title), "");
  	printf("| ");
  	for (int i = 0; i < name_col_width; i++)
  		putchar('-');
@@ -317,8 +318,9 @@ static void stats_table_print_structure(const struct stats_table *table)
  			value = entry->value;
  		}
  
-		printf("| %-*s | %*s |\n", name_col_width, item->string,
-		       value_col_width, value);
+		printf("| %s%*s | %*s%s |\n",
+		item->string, name_col_width - utf8_strwidth(item->string), "",
+		value_col_width - utf8_strwidth(value), "", value);
  	}
  }