BUG_ON_OPT_NEG(unset);
- options->context = strtol(arg, &s, 10);
- if (*s)
- return error(_("%s expects a numerical value"), "--unified");
+ if (arg) {
+ options->context = strtol(arg, &s, 10);
+ if (*s)
+ return error(_("%s expects a numerical value"), "--unified");
+ }
enable_patch_output(&options->output_format);
return 0;
DIFF_FORMAT_PATCH, DIFF_FORMAT_NO_OUTPUT),
OPT_CALLBACK_F('U', "unified", options, N_("<n>"),
N_("generate diffs with <n> lines context"),
- PARSE_OPT_NONEG, diff_opt_unified),
+ PARSE_OPT_NONEG | PARSE_OPT_OPTARG, diff_opt_unified),
OPT_BOOL('W', "function-context", &options->flags.funccontext,
N_("generate diffs with <n> lines context")),
OPT_BIT_F(0, "raw", &options->output_format,
--- /dev/null
+$ git diff -U1 initial..side
+diff --git a/dir/sub b/dir/sub
+index 35d242b..7289e35 100644
+--- a/dir/sub
++++ b/dir/sub
+@@ -2 +2,3 @@ A
+ B
++1
++2
+diff --git a/file0 b/file0
+index 01e79c3..f4615da 100644
+--- a/file0
++++ b/file0
+@@ -3 +3,4 @@
+ 3
++A
++B
++C
+diff --git a/file3 b/file3
+new file mode 100644
+index 0000000..7289e35
+--- /dev/null
++++ b/file3
+@@ -0,0 +1,4 @@
++A
++B
++1
++2
+$
--- /dev/null
+$ git diff -U2 initial..side
+diff --git a/dir/sub b/dir/sub
+index 35d242b..7289e35 100644
+--- a/dir/sub
++++ b/dir/sub
+@@ -1,2 +1,4 @@
+ A
+ B
++1
++2
+diff --git a/file0 b/file0
+index 01e79c3..f4615da 100644
+--- a/file0
++++ b/file0
+@@ -2,2 +2,5 @@
+ 2
+ 3
++A
++B
++C
+diff --git a/file3 b/file3
+new file mode 100644
+index 0000000..7289e35
+--- /dev/null
++++ b/file3
+@@ -0,0 +1,4 @@
++A
++B
++1
++2
+$
--- /dev/null
+$ git diff -U initial..side
+diff --git a/dir/sub b/dir/sub
+index 35d242b..7289e35 100644
+--- a/dir/sub
++++ b/dir/sub
+@@ -1,2 +1,4 @@
+ A
+ B
++1
++2
+diff --git a/file0 b/file0
+index 01e79c3..f4615da 100644
+--- a/file0
++++ b/file0
+@@ -1,3 +1,6 @@
+ 1
+ 2
+ 3
++A
++B
++C
+diff --git a/file3 b/file3
+new file mode 100644
+index 0000000..7289e35
+--- /dev/null
++++ b/file3
+@@ -0,0 +1,4 @@
++A
++B
++1
++2
+$