Add default arg to info question type

spec/findQuestionArgInInstruction_spec.sh

@@ -0,0 +1,40 @@
+Describe 'findQuestionArgInInstruction'
+  Include ./install.sh
+  instructions=('somearg:somevalue' 'default:one' 'choose from:blue,light green,red')
+
+  It 'finds nothing if no arg name given'
+    argValue=''
+    When call findQuestionArgInInstruction
+    The variable argValue should eq ''
+    The status should be success
+  End
+
+  It 'finds nothing if arg name does not exist'
+    argValue=''
+    When call findQuestionArgInInstruction 'arg name that does not exist'
+    The variable argValue should eq ''
+    The status should be failure
+  End
+
+  It 'finds nothing if instructions is empty'
+    instructions=()
+    argValue=''
+    When call findQuestionArgInInstruction 'some arg name'
+    The variable argValue should eq ''
+    The status should be failure
+  End
+
+  It 'finds arg value if instructions contains arg as first item'
+    argValue=''
+    When call findQuestionArgInInstruction 'somearg'
+    The variable argValue should eq 'somevalue'
+    The status should be success
+  End
+
+  It 'finds arg value if instructions contains arg among other items'
+    argValue=''
+    When call findQuestionArgInInstruction 'choose from'
+    The variable argValue should eq 'blue,light green,red'
+    The status should be success
+  End
+End