format-patch: Produce better output with --inline or --attach

This patch makes two small changes to improve the output of --inline
and --attach.

The first is to write a newline preceding the boundary. This is needed because
MIME defines the encapsulation boundary as including the preceding CRLF (or in
this case, just LF), so we should be writing one. Without this, the last
newline in the pre-diff content is consumed instead.

The second change is to always write the line termination character
(default: newline) even when using --inline or --attach. This is simply to
improve the aesthetics of the resulting message. When using --inline an email
client should render the resulting message identically to the non-inline
version. And when using --attach this adds a blank line preceding the
attachment in the email, which is visually attractive.

Signed-off-by: Kevin Ballard <kevin@sb.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

10 files changed, 34 insertions, 3 deletions

diff --git a/diff.c b/diff.c
index a07812c5c7..cbf25473c5 100644
--- a/diff.c
+++ b/diff.c
@@ -3223,11 +3223,10 @@ void diff_flush(struct diff_options *options)
 
 	if (output_format & DIFF_FORMAT_PATCH) {
 		if (separator) {
+			putc(options->line_termination, options->file);
 			if (options->stat_sep) {
 				/* attach patch instead of inline */
 				fputs(options->stat_sep, options->file);
-			} else {
-				putc(options->line_termination, options->file);
 			}
 		}
 
diff --git a/log-tree.c b/log-tree.c
index 5505606ed6..bd8b9e45ab 100644
--- a/log-tree.c
+++ b/log-tree.c
@@ -198,7 +198,7 @@ void log_write_email_headers(struct rev_info *opt, const char *name,
 		extra_headers = subject_buffer;
 
 		snprintf(buffer, sizeof(buffer) - 1,
-			 "--%s%s\n"
+			 "\n--%s%s\n"
 			 "Content-Type: text/x-patch;"
 			 " name=\"%s.diff\"\n"
 			 "Content-Transfer-Encoding: 8bit\n"
diff --git a/t/t4013/diff.format-patch_--attach_--stdout_initial..master b/t/t4013/diff.format-patch_--attach_--stdout_initial..master
index cf6891f748..43346b9ba4 100644
--- a/t/t4013/diff.format-patch_--attach_--stdout_initial..master
+++ b/t/t4013/diff.format-patch_--attach_--stdout_initial..master
@@ -19,6 +19,8 @@ This is the second commit.
  file2   |    3 ---
  3 files changed, 5 insertions(+), 3 deletions(-)
  delete mode 100644 file2
+
+
 --------------g-i-t--v-e-r-s-i-o-n
 Content-Type: text/x-patch; name="1bde4ae5f36c8d9abe3a0fce0c6aab3c4a12fe44.diff"
 Content-Transfer-Encoding: 8bit
@@ -75,6 +77,8 @@ Content-Transfer-Encoding: 8bit
  file1   |    3 +++
  2 files changed, 5 insertions(+), 0 deletions(-)
  create mode 100644 file1
+
+
 --------------g-i-t--v-e-r-s-i-o-n
 Content-Type: text/x-patch; name="9a6d4949b6b76956d9d5e26f2791ec2ceff5fdc0.diff"
 Content-Transfer-Encoding: 8bit
@@ -122,6 +126,8 @@ Content-Transfer-Encoding: 8bit
  file3   |    4 ++++
  3 files changed, 9 insertions(+), 0 deletions(-)
  create mode 100644 file3
+
+
 --------------g-i-t--v-e-r-s-i-o-n
 Content-Type: text/x-patch; name="c7a2ab9e8eac7b117442a607d5a9b3950ae34d5a.diff"
 Content-Transfer-Encoding: 8bit
diff --git a/t/t4013/diff.format-patch_--attach_--stdout_initial..master^ b/t/t4013/diff.format-patch_--attach_--stdout_initial..master^
index fe0258720c..d7490a9fd7 100644
--- a/t/t4013/diff.format-patch_--attach_--stdout_initial..master^
+++ b/t/t4013/diff.format-patch_--attach_--stdout_initial..master^
@@ -19,6 +19,8 @@ This is the second commit.
  file2   |    3 ---
  3 files changed, 5 insertions(+), 3 deletions(-)
  delete mode 100644 file2
+
+
 --------------g-i-t--v-e-r-s-i-o-n
 Content-Type: text/x-patch; name="1bde4ae5f36c8d9abe3a0fce0c6aab3c4a12fe44.diff"
 Content-Transfer-Encoding: 8bit
@@ -75,6 +77,8 @@ Content-Transfer-Encoding: 8bit
  file1   |    3 +++
  2 files changed, 5 insertions(+), 0 deletions(-)
  create mode 100644 file1
+
+
 --------------g-i-t--v-e-r-s-i-o-n
 Content-Type: text/x-patch; name="9a6d4949b6b76956d9d5e26f2791ec2ceff5fdc0.diff"
 Content-Transfer-Encoding: 8bit
diff --git a/t/t4013/diff.format-patch_--attach_--stdout_initial..side b/t/t4013/diff.format-patch_--attach_--stdout_initial..side
index 9ff828ee9d..38f790290a 100644
--- a/t/t4013/diff.format-patch_--attach_--stdout_initial..side
+++ b/t/t4013/diff.format-patch_--attach_--stdout_initial..side
@@ -17,6 +17,8 @@ Content-Transfer-Encoding: 8bit
  file3   |    4 ++++
  3 files changed, 9 insertions(+), 0 deletions(-)
  create mode 100644 file3
+
+
 --------------g-i-t--v-e-r-s-i-o-n
 Content-Type: text/x-patch; name="c7a2ab9e8eac7b117442a607d5a9b3950ae34d5a.diff"
 Content-Transfer-Encoding: 8bit
diff --git a/t/t4013/diff.format-patch_--inline_--stdout_--subject-prefix=TESTCASE_initial..master b/t/t4013/diff.format-patch_--inline_--stdout_--subject-prefix=TESTCASE_initial..master
index a8093be7ca..fca5cce373 100644
--- a/t/t4013/diff.format-patch_--inline_--stdout_--subject-prefix=TESTCASE_initial..master
+++ b/t/t4013/diff.format-patch_--inline_--stdout_--subject-prefix=TESTCASE_initial..master
@@ -19,6 +19,8 @@ This is the second commit.
  file2   |    3 ---
  3 files changed, 5 insertions(+), 3 deletions(-)
  delete mode 100644 file2
+
+
 --------------g-i-t--v-e-r-s-i-o-n
 Content-Type: text/x-patch; name="1bde4ae5f36c8d9abe3a0fce0c6aab3c4a12fe44.diff"
 Content-Transfer-Encoding: 8bit
@@ -75,6 +77,8 @@ Content-Transfer-Encoding: 8bit
  file1   |    3 +++
  2 files changed, 5 insertions(+), 0 deletions(-)
  create mode 100644 file1
+
+
 --------------g-i-t--v-e-r-s-i-o-n
 Content-Type: text/x-patch; name="9a6d4949b6b76956d9d5e26f2791ec2ceff5fdc0.diff"
 Content-Transfer-Encoding: 8bit
@@ -122,6 +126,8 @@ Content-Transfer-Encoding: 8bit
  file3   |    4 ++++
  3 files changed, 9 insertions(+), 0 deletions(-)
  create mode 100644 file3
+
+
 --------------g-i-t--v-e-r-s-i-o-n
 Content-Type: text/x-patch; name="c7a2ab9e8eac7b117442a607d5a9b3950ae34d5a.diff"
 Content-Transfer-Encoding: 8bit
diff --git a/t/t4013/diff.format-patch_--inline_--stdout_initial..master b/t/t4013/diff.format-patch_--inline_--stdout_initial..master
index aa110c0e7f..6d6fac3908 100644
--- a/t/t4013/diff.format-patch_--inline_--stdout_initial..master
+++ b/t/t4013/diff.format-patch_--inline_--stdout_initial..master
@@ -19,6 +19,8 @@ This is the second commit.
  file2   |    3 ---
  3 files changed, 5 insertions(+), 3 deletions(-)
  delete mode 100644 file2
+
+
 --------------g-i-t--v-e-r-s-i-o-n
 Content-Type: text/x-patch; name="1bde4ae5f36c8d9abe3a0fce0c6aab3c4a12fe44.diff"
 Content-Transfer-Encoding: 8bit
@@ -75,6 +77,8 @@ Content-Transfer-Encoding: 8bit
  file1   |    3 +++
  2 files changed, 5 insertions(+), 0 deletions(-)
  create mode 100644 file1
+
+
 --------------g-i-t--v-e-r-s-i-o-n
 Content-Type: text/x-patch; name="9a6d4949b6b76956d9d5e26f2791ec2ceff5fdc0.diff"
 Content-Transfer-Encoding: 8bit
@@ -122,6 +126,8 @@ Content-Transfer-Encoding: 8bit
  file3   |    4 ++++
  3 files changed, 9 insertions(+), 0 deletions(-)
  create mode 100644 file3
+
+
 --------------g-i-t--v-e-r-s-i-o-n
 Content-Type: text/x-patch; name="c7a2ab9e8eac7b117442a607d5a9b3950ae34d5a.diff"
 Content-Transfer-Encoding: 8bit
diff --git a/t/t4013/diff.format-patch_--inline_--stdout_initial..master^ b/t/t4013/diff.format-patch_--inline_--stdout_initial..master^
index 95e9ea4c59..18a1110def 100644
--- a/t/t4013/diff.format-patch_--inline_--stdout_initial..master^
+++ b/t/t4013/diff.format-patch_--inline_--stdout_initial..master^
@@ -19,6 +19,8 @@ This is the second commit.
  file2   |    3 ---
  3 files changed, 5 insertions(+), 3 deletions(-)
  delete mode 100644 file2
+
+
 --------------g-i-t--v-e-r-s-i-o-n
 Content-Type: text/x-patch; name="1bde4ae5f36c8d9abe3a0fce0c6aab3c4a12fe44.diff"
 Content-Transfer-Encoding: 8bit
@@ -75,6 +77,8 @@ Content-Transfer-Encoding: 8bit
  file1   |    3 +++
  2 files changed, 5 insertions(+), 0 deletions(-)
  create mode 100644 file1
+
+
 --------------g-i-t--v-e-r-s-i-o-n
 Content-Type: text/x-patch; name="9a6d4949b6b76956d9d5e26f2791ec2ceff5fdc0.diff"
 Content-Transfer-Encoding: 8bit
diff --git a/t/t4013/diff.format-patch_--inline_--stdout_initial..master^^ b/t/t4013/diff.format-patch_--inline_--stdout_initial..master^^
index b8e81e1552..4f258b8858 100644
--- a/t/t4013/diff.format-patch_--inline_--stdout_initial..master^^
+++ b/t/t4013/diff.format-patch_--inline_--stdout_initial..master^^
@@ -19,6 +19,8 @@ This is the second commit.
  file2   |    3 ---
  3 files changed, 5 insertions(+), 3 deletions(-)
  delete mode 100644 file2
+
+
 --------------g-i-t--v-e-r-s-i-o-n
 Content-Type: text/x-patch; name="1bde4ae5f36c8d9abe3a0fce0c6aab3c4a12fe44.diff"
 Content-Transfer-Encoding: 8bit
diff --git a/t/t4013/diff.format-patch_--inline_--stdout_initial..side b/t/t4013/diff.format-patch_--inline_--stdout_initial..side
index 86ae923d71..e86dce69a3 100644
--- a/t/t4013/diff.format-patch_--inline_--stdout_initial..side
+++ b/t/t4013/diff.format-patch_--inline_--stdout_initial..side
@@ -17,6 +17,8 @@ Content-Transfer-Encoding: 8bit
  file3   |    4 ++++
  3 files changed, 9 insertions(+), 0 deletions(-)
  create mode 100644 file3
+
+
 --------------g-i-t--v-e-r-s-i-o-n
 Content-Type: text/x-patch; name="c7a2ab9e8eac7b117442a607d5a9b3950ae34d5a.diff"
 Content-Transfer-Encoding: 8bit