From a1e28c44113207313b8fe598f6d99d9424724f00 Mon Sep 17 00:00:00 2001
From: Jacob Niehus <jacob.niehus@gmail.com>
Date: Sat, 1 Aug 2015 20:15:15 -0700
Subject: [PATCH 1/3] Change indent comparison to !~ with explanation

Truth table:
 x   x != 0  x !~ 0
 0      0      0
 1      1      1
'=='    0      1
---
 plugin/exchange.vim | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/plugin/exchange.vim b/plugin/exchange.vim
index 762b189..044cd74 100644
--- a/plugin/exchange.vim
+++ b/plugin/exchange.vim
@@ -8,7 +8,8 @@ function! s:exchange(x, y, reverse, expand)
 	let selection = &selection
 	set selection=inclusive
 
-	let indent = s:get_setting('exchange_indent', 1) != 0 && a:x.type ==# 'V' && a:y.type ==# 'V'
+	" Compare using =~ because "'==' != 0" returns 0
+	let indent = s:get_setting('exchange_indent', 1) !~ 0 && a:x.type ==# 'V' && a:y.type ==# 'V'
 
 	if indent
 		let xindent = matchstr(getline(nextnonblank(a:y.start.line)), '^\s*')

From d54c7e27fe169254299b9972216c1793129f426b Mon Sep 17 00:00:00 2001
From: Jacob Niehus <jacob.niehus@gmail.com>
Date: Sat, 1 Aug 2015 20:19:31 -0700
Subject: [PATCH 2/3] Prevent calling setline() incorrectly

Automatic re-indenting shouldn't call setline() on a line outside of the
exchange region. It currently does so if the exchange region only
contains blank lines.
---
 plugin/exchange.vim | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/plugin/exchange.vim b/plugin/exchange.vim
index 044cd74..4155d4b 100644
--- a/plugin/exchange.vim
+++ b/plugin/exchange.vim
@@ -69,6 +69,9 @@ endfunction
 function! s:reindent(start, lines, new_indent)
 	if s:get_setting('exchange_indent', 1) == '=='
 		let lnum = nextnonblank(a:start)
+		if lnum == 0 || lnum > a:start + a:lines - 1
+				return
+		endif
 		let line = getline(lnum)
 		execute "silent normal! " . lnum . "G=="
 		let new_indent = matchstr(getline(lnum), '^\s*')

From 1ff6e3c65baa6762c8505bfb9ea02900a4bfa590 Mon Sep 17 00:00:00 2001
From: Jacob Niehus <jacob.niehus@gmail.com>
Date: Sun, 2 Aug 2015 10:13:13 -0700
Subject: [PATCH 3/3] Fix indentation of return line

---
 plugin/exchange.vim | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/plugin/exchange.vim b/plugin/exchange.vim
index 4155d4b..e3491f5 100644
--- a/plugin/exchange.vim
+++ b/plugin/exchange.vim
@@ -70,7 +70,7 @@ function! s:reindent(start, lines, new_indent)
 	if s:get_setting('exchange_indent', 1) == '=='
 		let lnum = nextnonblank(a:start)
 		if lnum == 0 || lnum > a:start + a:lines - 1
-				return
+			return
 		endif
 		let line = getline(lnum)
 		execute "silent normal! " . lnum . "G=="