Expand Dotfile syntax support to not require a <source> argument

Supported action syntax:

- `<action>: <source> -> <target>`
- `<action>: -> <target>`
- `<source> -> <target>`
- `-> <target>`

examples/Dotfile

@@ -24,9 +24,13 @@ gitignore -> .gitignore
 hgrc      -> .hgrc
 irbrc     -> .irbrc
 powconfig -> .powconfig
-rspec     -> .rspec
+
-tmux      -> .tmux
+# The following examples uses the link action, without specifying a <source>,
-tmux.conf -> .tmux.conf
+# in this case the link action is smart enough to determine the source value
+# for ".rspec" for example to be "rspec".
+link: -> .rspec
+-> .tmux
+-> .tmux.conf
 
 # The same source can be symlinked to multiple targets.
 load_shellrc.sh -> .profile

src/lib/internals/compile-dotfile.sh

@@ -20,12 +20,22 @@ compile-dotfile() {
       output="${output}$(trim "${BASH_REMATCH[3]}") "
       output="${output}$(trim "${BASH_REMATCH[4]}")\n"
 
+    # Parse "<action>: -> <target>" lines.
+    elif [[ "$line" =~ ^(\ +)?([a-zA-Z0-9_-]+):\ *-[\>]\ +(.+)$ ]]; then
+      output="${output}${BASH_REMATCH[1]}dotify-action ${BASH_REMATCH[2]} "
+      output="${output}$(trim "${BASH_REMATCH[3]}")\n"
+
     # Parse "<source> -> <target>" lines.
     elif [[ "$line" =~ ^(\ +)?(.+)\ -[\>]\ (.+)$ ]]; then
       output="${output}${BASH_REMATCH[1]}dotify-action default "
       output="${output}$(trim "${BASH_REMATCH[2]}") "
       output="${output}$(trim "${BASH_REMATCH[3]}")\n"
 
+    # Parse "-> <target>" lines.
+    elif [[ "$line" =~ ^(\ +)?-[\>]\ (.+)$ ]]; then
+      output="${output}${BASH_REMATCH[1]}dotify-action default "
+      output="${output}$(trim "${BASH_REMATCH[2]}")\n"
+
     # Append line without modifications.
     else
       output="${output}${line}\n"

test/lib/internals/compile-dotfile-test.sh

@@ -39,6 +39,15 @@ dotify-action link ackrc .ackrc
 dotify-action link gitconfig \".gitconfig\""
 
 
+# Compiles standard actions without a <source>
+echo -e "root_link .dotfiles
+link: -> .ackrc
+link:-> \".gitconfig\"" > $dotfile
+assert "compile-dotfile $dotfile" "root_link .dotfiles
+dotify-action link .ackrc
+dotify-action link \".gitconfig\""
+
+
 # Compiles default (shorthand) actions
 echo -e "root_link .dotfiles
 link: ackrc -> .ackrc
@@ -48,6 +57,15 @@ dotify-action link ackrc .ackrc
 dotify-action default gitconfig \".gitconfig\""
 
 
+# Compiles default (shorthand) actions without a <source>
+echo -e "root_link .dotfiles
+-> .ackrc
+ -> \".gitconfig\"" > $dotfile
+assert "compile-dotfile $dotfile" "root_link .dotfiles
+dotify-action default .ackrc
+ dotify-action default \".gitconfig\""
+
+
 # Correctly indents actions
 echo -e "root_link .dotfiles
 if [ true ]; then