Reusable lists

public/js/wtfismygenericthing.js

@@ -1,3 +1,13 @@
+function extract(list) {
+  var index = Math.floor(Math.random() * list.length)
+  a = {}
+  a['victim'] = list[index]
+  list.splice(index, 1)
+  a['remainder'] = list
+
+  return(a)
+}
+
 function isLetter(char) {
   return('abcdefghijklmnopqrstuvwxyz@'.indexOf(char.toLowerCase()) > -1)
 }
@@ -56,18 +66,20 @@ function chunks(string) {
   return separate(string)
 }
 
-function substitute(chunk, json) {
-  if(isPlaceholder(chunk)) {
-    return getRandom(json[stripFirst(chunk)])
-  } else {
-    return chunk
-  }
-}
-
 function populateTemplate(template, json) {
   var populated = []
   $.each(chunks(template), function(index, chunk) {
-    populated.push(substitute(chunk, json))
+
+    subs = ''
+    if(isPlaceholder(chunk)) {
+      extracted = extract(json[stripFirst(chunk)])
+      subs = extracted['victim']
+      json[chunk] = extracted['remainder']
+    } else {
+      subs = chunk
+    }
+    populated.push(subs)
+
   })
   complete = populated.join('')
 

spec/javascripts/list_spec.js

@@ -0,0 +1,88 @@
+describe('Resusable lists', function() {
+  describe('return a list item and remove it from the list', function() {
+    it('pulls out an item', function() {
+      items = [
+        'Brockway',
+        'North Haverbrook',
+        'Ogdenville'
+      ]
+      var extracted = extract(items)
+      expect(extracted['remainder'].length).toEqual(2)
+
+      switch(extracted['victim']) {
+        case 'Brockway':
+          expect(extracted['remainder']).toEqual([
+            'North Haverbrook',
+            'Ogdenville'
+          ])
+          break
+
+        case 'North Haverbrook':
+          expect(extracted['remainder']).toEqual([
+            'Brockway',
+            'Ogdenville'
+          ])
+          break
+
+        case 'Ogdenville':
+          expect(extracted['remainder']).toEqual([
+            'Brockway',
+            'North Haverbrook'
+          ])
+      }
+    })
+  })
+
+  describe('populate a template with a repeated placeholder', function() {
+    var json = {
+      'templates': [
+        '@these and @these'
+      ],
+      'these': [
+        'this',
+        'that'
+      ]
+    }
+
+    it('reuses the list', function() {
+      templated = template(json)
+      switch(templated.substring(0, 4)) {
+        case 'this':
+          expect(templated).toEqual('this and that')
+          break
+
+        case 'that':
+          expect(templated).toEqual('that and this')
+          break
+      }
+    })
+
+    describe('with a recursive template', function() {
+      var json = {
+        'templates': [
+          '@things and @stuff'
+        ],
+        'things': [
+          'Lions',
+          'Tigers',
+          'Bears'
+        ],
+        'stuff': [
+          '@things and @things'
+        ]
+      }
+
+      it('reuses the list when things get recursive', function() {
+        templated = template(json)
+        words = templated.split(' ').sort()
+        expect(words).toEqual([
+          'Bears',
+          'Lions',
+          'Tigers',
+          'and',
+          'and'
+        ])
+      })
+    })
+  })
+})

spec/javascripts/wtfismygenericthing_spec.js

@@ -56,15 +56,6 @@ describe('Templates', function() {
     ]
   }
 
-  describe('replace', function() {
-    it('replaces a placeholder', function() {
-      expect(substitute('@things', json)).toEqual('cats')
-    })
-    it('ignores a non-placeholder', function() {
-      expect(substitute('plain', json)).toEqual('plain')
-    })
-  })
-
   describe('populateTemplate', function() {
     var template = 'Put @things into @stuff'
     it('fills a simple template', function() {