Fill out, polish the rule spec a little more.

Drop use of startsWith in favor of indexOf for PhantomJS testing.

client/galaxy/scripts/mvc/rules/rule-definitions.js

@@ -167,7 +167,7 @@ const RULES = {
         apply: (rule, data, sources, columns) => {
             const ruleValue = rule.value;
             let newRow;
-            if (ruleValue.startsWith("identifier")) {
+            if (ruleValue.indexOf("identifier") == 0) {
                 const identifierIndex = parseInt(ruleValue.substring("identifier".length));
                 newRow = (row, index) => {
                     const newRow = row.slice();

test/base/data/rules_dsl_spec.yml

@@ -325,6 +325,7 @@
   final:
     data: [["20", "dog"], ["30", "cat"]]
     sources: [4, 5]
+
 - rules:
     - type: add_filter_compare
       target_column: 0
@@ -336,6 +337,7 @@
   final:
     data: [["13", "rat"], ["20", "dog"], ["30", "cat"]]
     sources: [3, 4, 5]
+
 - rules:
     - type: sort
       numeric: false
@@ -346,6 +348,7 @@
   final:
     data: [["bark", "dog"], ["meow", "cat"], ["moo", "cow"]]
     sources: [3, 2, 1]
+
 - rules:
     - type: sort
       numeric: false
@@ -356,6 +359,7 @@
   final:
     data: [["meow", "cat"], ["moo", "cow"], ["bark", "dog"]]
     sources: [2, 1, 3]
+
 - rules:
     - type: sort
       numeric: false
@@ -366,6 +370,7 @@
   final:
     data: [["bark", "Dog"], ["meow", "cat"], ["moo", "cow"]]
     sources: [3, 2, 1]
+
 - rules:
     - type: swap_columns
       target_column_0: 0
@@ -376,6 +381,7 @@
   final:
     data: [["cow", "moo"], ["cat", "meow"], ["Dog", "bark"]]
     sources: [1, 2, 3]
+
 - rules:
     - type: split_columns
       target_columns_0: [0]
@@ -386,28 +392,43 @@
   final:
     data: [["moo", "A"], ["cow", "A"], ["meow", "B"], ["cat", "B"], ["bark", "C"], ["Dog", "C"]]
     sources: [1, 1, 2, 2, 3, 3]
+
+- rules:
+    - type: add_column_metadata
+      value: identifier0
+  initial:
+    data: [["moo"], ["meow"], ["bark"]]
+    sources: [{"identifiers": ["cow"]}, {"identifiers": ["cat"]}, {"identifiers": ["dog"]}]
+  final:
+    data: [["moo", "cow"], ["meow", "cat"], ["bark", "dog"]]
+
 - rules:
     - type: invalid_rule_type
   error: true
+
 - rules:
     - type: add_filter_compare
       target_column: 0
       value: 13
       compare_type: invalid_compare_type
   error: true
+
 - rules:
     - type: add_column_concatenate
       target_column: 0
   error: true
+
 - rules:
     - type: add_column_basename
       target_column_0: 0
   error: true
+
 - rules:
     - type: add_column_regex
       target_column: 0
       regex: '(o)+'
   error: true
+
 - rules:
     - type: add_column_regex
       target_column: 0