Implementing a search path

Closes #30

tests/double-hyphen.expected

@@ -1 +1 @@
-cat: --help: No such file or directory
+File does not exist: /home/fidian/repo/mo/tests/--help

tests/double-hyphen.sh

@@ -2,4 +2,4 @@
 # This should display a message indicating that the file --help
 # could not be found.  It should not display a help messsage.
 cd "${0%/*}"
-../mo -- --help 2>&1
+../mo -u -- --help 2>&1

tests/help.expected

@@ -9,9 +9,19 @@ Learn more about mustache templates at https://mustache.github.io/
 
 Simple usage:
 
-   mo [--false] [--help] [--source=FILE] filenames...
+   mo [OPTIONS] filenames...
 
---fail-not-set - Fail upon expansion of an unset variable.
---false        - Treat the string "false" as empty for conditionals.
---help         - This message.
---source=FILE  - Load FILE into the environment before processing templates.
+Options:
+
+   -u, --fail-not-set
+         - Fail upon expansion of an unset variable.
+   -e, --false
+         - Treat the string "false" as empty for conditionals.
+   -h, --help
+         - This message.
+   -s=FILE, --source=FILE
+         - Load FILE into the environment before processing templates.
+   -p=PATH, --path=PATH
+         - Set a colon-delimited list of folders to search for templates.
+
+MO_VERSION=2.0.4

tests/help.sh

@@ -1,4 +1,4 @@
 #!/usr/bin/env bash
 
 cd "${0%/*}"
-../mo --help
+../mo -u --help

tests/invalid-option.expected

@@ -1 +0,0 @@
-cat: --something: No such file or directory

tests/partial-missing.expected

@@ -1 +1 @@
-cat: partial-missing.partial: No such file or directory
+File does not exist: /home/fidian/repo/mo/tests/partial-missing.partial

tests/partial-missing.sh

@@ -1,8 +1,9 @@
 #!/usr/bin/env bash
 
 cd "${0%/*}"
-../mo partial-missing.template 2>&1
+../mo -u partial-missing.template 2>&1
+returned=$?
 
-if [[ $? -ne 1 ]]; then
-    echo "Did not return 1"
+if [[ $returned -ne 1 ]]; then
+    echo "Did not return 1. Instead, returned $returned."
 fi

tests/source.sh

@@ -1,7 +1,8 @@
 #!/usr/bin/env bash
 
 cd "${0%/*}"
-cat <<EOF | ../mo --source=source.vars
+. ../mo
+cat <<EOF | mo --source=source.vars
 {{VAR}}
 {{#ARR}}
 * {{.}}

tests/source.vars

@@ -1,4 +1,4 @@
 export VAR=value
 export ARR=(1 2 3)
 declare -A ASSOC_ARR
-export ASSOC_ARR=([a]=AAA [b]=BBB)
+ASSOC_ARR=([a]=AAA [b]=BBB)