rc tools patch: skip patch message signature, fixing diff application

Patches as produced by "git format-patch" have a trailing signature
that is separated from the body by a line with "-- " on it.  By default
it contains the Git version.  We erroneously include this signature
in the diff we pipe to patch, which fails to apply as a result.

Add a targeted fix to suppress these signatures.

4 files changed, 32 insertions, 0 deletions

diff --git a/test/tools/patch/signature/cmd b/test/tools/patch/signature/cmd
new file mode 100644
index 00000000..2b5ac0b6
--- /dev/null
+++ b/test/tools/patch/signature/cmd
@@ -0,0 +1 @@
+%:patch tee applied.diff<ret><ret>!echo Applied:; cat applied.diff; echo; echo Updated buffer:<ret>
diff --git a/test/tools/patch/signature/in b/test/tools/patch/signature/in
new file mode 100644
index 00000000..acceecf7
--- /dev/null
+++ b/test/tools/patch/signature/in
@@ -0,0 +1,10 @@
+diff -ur a/file1 b/file1
+--- a/file1
++++ b/file1
+@@ -1,3 +1,3 @@
+ context
+-file1 here
++modified file1 here
+ context
+-- 
+2.43.0
diff --git a/test/tools/patch/signature/out b/test/tools/patch/signature/out
new file mode 100644
index 00000000..3c4120f3
--- /dev/null
+++ b/test/tools/patch/signature/out
@@ -0,0 +1,20 @@
+Applied:
+diff -ur a/file1 b/file1
+--- a/file1
++++ b/file1
+@@ -1,3 +1,3 @@
+ context
+-file1 here
++modified file1 here
+ context
+
+Updated buffer:
+diff -ur a/file1 b/file1
+--- a/file1
++++ b/file1
+@@ -1,3 +1,3 @@
+ context
+ modified file1 here
+ context
+-- 
+2.43.0
diff --git a/test/tools/patch/signature/rc b/test/tools/patch/signature/rc
new file mode 100644
index 00000000..62ee8585
--- /dev/null
+++ b/test/tools/patch/signature/rc
@@ -0,0 +1 @@
+source "%val{runtime}/rc/tools/patch.kak"