unposted: vcs_info: Break out VCS_INFO_quilt-patch2subject into VCS_INFO_patch2subject

... so other places can use it; compare 40030 in the 39990 thread.

ChangeLog

@@ -1,3 +1,10 @@
+2016-12-01  Daniel Shahaf  <d.s@daniel.shahaf.name>
+
+	* unposted: Functions/VCS_Info/VCS_INFO_patch2subject,
+	Functions/VCS_Info/VCS_INFO_quilt, Functions/VCS_Info/vcs_info:
+	vcs_info: Break out VCS_INFO_quilt-patch2subject into
+	VCS_INFO_patch2subject
+
 2016-12-01  Mikael Magnusson  <mikachu@gmail.com>
 
 	* 40024: Completion/Unix/Type/_path_files: Update _path_files

Functions/VCS_Info/VCS_INFO_patch2subject

@@ -0,0 +1,50 @@
+# This function takes as an argument a filename of a patch and sets $REPLY to
+# a single-line "subject", or unsets it if no subject could be extracted.
+{
+    integer i
+    integer -r LIMIT=10
+    local -a lines
+    local needle
+    if [[ -f "$1" ]]; then
+        # Extract the first LIMIT lines, or up to the first empty line or the start of the unidiffs,
+        # whichever comes first.
+        while (( i++ < LIMIT )); do
+            IFS= read -r "lines[$i]"
+            if [[ -z ${lines[$i]} ]] || [[ ${lines[$i]} == (#b)(---|Index:)* ]]; then
+                lines[$i]=()
+                break
+            fi
+        done < "$1"
+        
+        if needle=${lines[(i)Subject:*]}; (( needle <= $#lines )); then
+            # "Subject: foo" line, plus rfc822 whitespace unfolding.
+            #
+            # Example: 'git format-patch' patches.
+            REPLY=${lines[needle]}
+            REPLY=${REPLY#*: }
+            REPLY=${REPLY#\[PATCH\] }
+            while [[ ${${lines[++needle]}[1]} == ' ' ]]; do
+                REPLY+=${lines[needle]}
+            done
+        elif needle=${lines[(r)Description:*]}; [[ -n $needle ]]; then
+            # "Description: foo" line.
+            #
+            # Example: DEP-3 patches.
+            REPLY=${needle#*: }
+        elif [[ ${lines[1]} == '# HG changeset patch' ]] && { needle=${${lines:#([#]*)}[1]}; [[ -n $needle ]] }; then
+            # Mercurial patch
+            REPLY=$needle
+        elif (( ${+lines[1]} )); then
+            # The first line of the file is not part of the diff.
+            REPLY=${lines[1]}
+        else
+            # The patch has no subject.
+            unset REPLY
+            return 0
+        fi
+    else
+        # The patch cannot be examined, or invalid arguments.
+        unset REPLY
+        return 1
+    fi
+}

Functions/VCS_Info/VCS_INFO_quilt

@@ -80,55 +80,8 @@ function VCS_INFO_quilt-dirfind() {
     return ${ret}
 }
 
-# This function takes as an argument a filename of a patch and sets $REPLY to
-# a single-line "subject", or unsets it if no subject could be extracted.
 function VCS_INFO_quilt-patch2subject() {
-    integer i
-    integer -r LIMIT=10
-    local -a lines
-    local needle
-    if [[ -f "$1" ]]; then
-        # Extract the first LIMIT lines, or up to the first empty line or the start of the unidiffs,
-        # whichever comes first.
-        while (( i++ < LIMIT )); do
-            IFS= read -r "lines[$i]"
-            if [[ -z ${lines[$i]} ]] || [[ ${lines[$i]} == (#b)(---|Index:)* ]]; then
-                lines[$i]=()
-                break
-            fi
-        done < "$1"
-        
-        if needle=${lines[(i)Subject:*]}; (( needle <= $#lines )); then
-            # "Subject: foo" line, plus rfc822 whitespace unfolding.
-            #
-            # Example: 'git format-patch' patches.
-            REPLY=${lines[needle]}
-            REPLY=${REPLY#*: }
-            REPLY=${REPLY#\[PATCH\] }
-            while [[ ${${lines[++needle]}[1]} == ' ' ]]; do
-                REPLY+=${lines[needle]}
-            done
-        elif needle=${lines[(r)Description:*]}; [[ -n $needle ]]; then
-            # "Description: foo" line.
-            #
-            # Example: DEP-3 patches.
-            REPLY=${needle#*: }
-        elif [[ ${lines[1]} == '# HG changeset patch' ]] && { needle=${${lines:#([#]*)}[1]}; [[ -n $needle ]] }; then
-            # Mercurial patch
-            REPLY=$needle
-        elif (( ${+lines[1]} )); then
-            # The first line of the file is not part of the diff.
-            REPLY=${lines[1]}
-        else
-            # The patch has no subject.
-            unset REPLY
-            return 0
-        fi
-    else
-        # The patch cannot be examined, or invalid arguments.
-        unset REPLY
-        return 1
-    fi
+    VCS_INFO_patch2subject "$@"
 }
 
 function VCS_INFO_quilt() {

Functions/VCS_Info/vcs_info

@@ -23,6 +23,7 @@ static_functions=(
     VCS_INFO_hook
     VCS_INFO_maxexports
     VCS_INFO_nvcsformats
+    VCS_INFO_patch2subject
     VCS_INFO_quilt
     VCS_INFO_realpath
     VCS_INFO_reposub