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[PATCH v1] diff: document -U without <n> as using default context

From
Tian Yuchen <cat@malon.dev>
Date
Mar 9, 2026, 17:27 UTC
Message-ID
<20260309172719.125419-1-cat@malon.dev>
In-Reply-To
<xmqqh5qswo45.fsf@gitster.g>

The documentation for '-U<n>' implies that the numeric value '<n>' is mandatory. However, the command line parser has historically accepted '-U' without a number.

Strictly requiring a number for '-U' would break existing tests (e.g., in 't4013') and likely disrupt user scripts relying on this undocumented behavior.

Since we are retaining this fallback behavior for backward compatibility, update the documentation to explicitly state that '<n>' can be omitted for the short option '-U'.

Signed-off-by: Tian Yuchen <cat@malon.dev>
---
 Documentation/diff-context-options.adoc | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/Documentation/diff-context-options.adoc b/Documentation/diff-context-options.adoc
index e161260358..655496ec3a 100644
--- a/Documentation/diff-context-options.adoc
+++ b/Documentation/diff-context-options.adoc
@@ -1,4 +1,4 @@
-`-U<n>`::
+`-U[<n>]`::
 `--unified=<n>`::
 	Generate diffs with _<n>_ lines of context. Defaults to `diff.context`
 	or 3 if the config option is unset.
-- 
2.43.0
Previous: Tian YuchenNext: D. Ben Knoble
Message 3 of 14 in “An annoying "Bug" that we would probably leave as-is”
  1. Junio C HamanoMar 6, 2026
  2. Tian YuchenMar 9, 2026
  3. diff: document -U without <n> as using default contextTian Yuchen, Mar 9, 2026
  4. D. Ben KnobleMar 9, 2026
  5. Tian YuchenMar 10, 2026
  6. Junio C HamanoMar 9, 2026
  7. Tian YuchenMar 10, 2026
  8. diff: document -U without <n> as using default contextTian Yuchen, Mar 10, 2026
  9. Oswald BuddenhagenMar 10, 2026
  10. Tian YuchenMar 10, 2026
  11. Junio C HamanoMar 10, 2026
  12. diff: document -U without <n> as using default contextTian Yuchen, Mar 10, 2026
  13. Jean-Noël AVILAMar 10, 2026
  14. Tian YuchenMar 11, 2026

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