diff --git a/test/lib/arguments-test.sh b/test/lib/arguments-test.sh
new file mode 100755
index 0000000..a812193
--- /dev/null
+++ b/test/lib/arguments-test.sh
@@ -0,0 +1,51 @@
+#! /usr/bin/env bash
+source "../assert.sh"
+
+source "../../src/lib/arguments.sh"
+
+
+#
+# has-argument()
+#
+
+# Returns 1 when it does not have argument.
+assert_raises 'has-argument help h -v -f --debug' 1
+
+# Returns 0 when any form of the argument is present.
+assert_raises 'has-argument help h -v --help' 0
+assert_raises 'has-argument help h -v --help=wtf' 0
+assert_raises 'has-argument help h -v -h' 0
+assert_raises 'has-argument help h -v -h=wtf' 0
+
+assert_end "has-argument()"
+
+
+#
+# parse-argument()
+#
+
+# Echos nothing and returns 1 when argument is not present.
+assert        'parse-argument file f -v --debug' ""
+assert_raises 'parse-argument file f -v --debug' 1
+
+# echos value of argument and returns 0 when any form of argument is present.
+assert        'parse-argument file f -v --file foo/bar.txt' "foo/bar.txt"
+assert_raises 'parse-argument file f -v --file foo/bar.txt' 0
+assert        'parse-argument file f -v --file=foo/bar.txt' "foo/bar.txt"
+assert_raises 'parse-argument file f -v --file=foo/bar.txt' 0
+assert        'parse-argument file f -v -f foo/bar.txt' "foo/bar.txt"
+assert_raises 'parse-argument file f -v -f foo/bar.txt' 0
+assert        'parse-argument file f -v -f=foo/bar.txt' "foo/bar.txt"
+assert_raises 'parse-argument file f -v -f=foo/bar.txt' 0
+
+# Value with a space.
+assert 'parse-argument file f -v --file foo\ bar.txt' "foo bar.txt"
+assert 'parse-argument file f -v --file "foo bar.txt"' "foo bar.txt"
+assert "parse-argument file f -v --file 'foo bar.txt'" "foo bar.txt"
+
+assert 'parse-argument file f -v --file=foo\ bar.txt' "foo bar.txt"
+assert 'parse-argument file f -v --file="foo bar.txt"' "foo bar.txt"
+assert "parse-argument file f -v --file='foo bar.txt'" "foo bar.txt"
+
+
+assert_end "parse-argument()"