Add set quality comparison to ignore filter

Add new syntax for supporting set equality checks for parameters
with arrays of values where order is not important.

Author: seanmil

doc/advanced-ignores.md

@@ -222,3 +222,13 @@ File[/tmp/foo] =>
 In this case, the very important line was removed from the catalog, and you want to know about this. Ignoring `File[/tmp/foo]::parameters::content` would have suppressed this (because all changes to that attribute are ignored). Also ignoring `File[/tmp/foo]::parameters::content=~>This is the line in the new catalog that I do not care about$` would have also suppressed this (because the regular expression was matched for *one* of the lines). However, the two examples with `=&>` in this section would *not* have suppressed this change, because it is no longer the case that *all* changes in the file matched the regular expression.
 
 :warning: All lines are stripped of leading and trailing spaces before the regular expression match is tried. This stripping of whitespace is done *only* for this comparison stage, and does not affect the display of any results.
+
+#### Ignoring attributes which have identical elements but in arbitrary order
+
+You can ignore attributes where both the values in both the old and new catalogs are arrays and the arrays
+contain identical elements but in arbitrary order. Basically, you can ignore a parameter where the values
+have set equality.
+
+To ignore any parameters named `foo` with values having set equality, you would use:
+
+      --ignore 'My::Custom::Resource[*]::parameters::foo=s>='

lib/octocatalog-diff/catalog-diff/differ.rb

@@ -340,7 +340,8 @@ def attr_match_rule?(rule, attrib, old_val, new_val)
         #   =->  Attribute must have been removed and equal this
         #   =~>  Change must match regexp (one line of change matching is sufficient)
         #   =&>  Change must match regexp (all lines of change MUST match regexp)
-        if rule_attr =~ /\A(.+?)(=[\-\+~&]?>)(.+)/m
+        #   =s>  Change must be array and contain identical elements, ignoring order
+        if rule_attr =~ /\A(.+?)(=[\-\+~&s]?>)(.+)/m
           rule_attr = Regexp.last_match(1)
           operator = Regexp.last_match(2)
           value = Regexp.last_match(3)
@@ -361,6 +362,9 @@ def attr_match_rule?(rule, attrib, old_val, new_val)
               raise RegexpError, "Invalid ignore regexp for #{key}: #{exc.message}"
             end
             matcher = ->(x, y) { regexp_operator_match?(operator, my_regex, x, y) }
+          elsif operator == '=s>'
+            raise ArgumentError, "Invalid ignore option for =s>, must be '='" unless value == '='
+            matcher = ->(x, y) { x.is_a?(Array) && y.is_a?(Array) && Set.new(x) == Set.new(y) }
           end
         end
 

spec/octocatalog-diff/fixtures/catalogs/ignore-parameter-set-1.json

@@ -0,0 +1,28 @@
+{
+  "document_type": "Catalog",
+  "data": {
+    "tags": ["settings"],
+    "name": "my.rspec.node",
+    "version": "production",
+    "environment": "production",
+    "resources": [
+      {
+        "type": "Myres",
+        "title": "res1",
+        "file": "/environments/production/modules/foo/manifests/init.pp",
+        "line": 10,
+        "exported": false,
+        "parameters": {
+          "set1": ["one", "two", "three"],
+          "set2": ["a", "b"]
+        }
+      }
+    ],
+    "classes": [
+      "settings"
+    ]
+  },
+  "metadata": {
+    "api_version": 1
+  }
+}

spec/octocatalog-diff/fixtures/catalogs/ignore-parameter-set-2.json

@@ -0,0 +1,29 @@
+{
+  "document_type": "Catalog",
+  "data": {
+    "tags": ["settings"],
+    "name": "my.rspec.node",
+    "version": "production",
+    "environment": "production",
+    "resources": [
+      {
+        "type": "Myres",
+        "title": "res1",
+        "file": "/environments/production/modules/foo/manifests/init.pp",
+        "line": 10,
+        "exported": false,
+        "parameters": {
+          "set1": ["three", "two", "one"],
+          "set2": ["a", "b", "c"],
+          "set3": [1, 2, 3]
+        }
+      }
+    ],
+    "classes": [
+      "settings"
+    ]
+  },
+  "metadata": {
+    "api_version": 1
+  }
+}

spec/octocatalog-diff/tests/catalog-diff/differ_spec.rb

@@ -1234,6 +1234,73 @@
     end
   end
 
+  context 'ignoring changes in sets' do
+    describe '#ignore' do
+      before(:all) do
+        @c1 = OctocatalogDiff::Catalog.create(json: OctocatalogDiff::Spec.fixture_read('catalogs/ignore-parameter-set-1.json'))
+        @c2 = OctocatalogDiff::Catalog.create(json: OctocatalogDiff::Spec.fixture_read('catalogs/ignore-parameter-set-2.json'))
+        @set1 = [
+          '!',
+          "Myres\fres1\fparameters\fset1",
+          %w(one two three),
+          %w(three two one)
+        ]
+        @set2 = [
+          '!',
+          "Myres\fres1\fparameters\fset2",
+          %w(a b),
+          %w(a b c)
+        ]
+        @set3 = [
+          '!',
+          "Myres\fres1\fparameters\fset3",
+          nil,
+          [1, 2, 3]
+        ]
+      end
+
+      it 'should not filter out a change when attribute does not match' do
+        opts = {}
+        testobj = OctocatalogDiff::CatalogDiff::Differ.new(opts, @c1, @c2)
+        testobj.ignore(type: 'Myres', title: 'res1', attr: "parameters\fmode")
+        result = testobj.diff
+        expect(OctocatalogDiff::Spec.array_contains_partial_array?(result, @set1)).to eq(true)
+        expect(OctocatalogDiff::Spec.array_contains_partial_array?(result, @set2)).to eq(true)
+        expect(OctocatalogDiff::Spec.array_contains_partial_array?(result, @set3)).to eq(true)
+      end
+
+      it 'should filter out a change when two arrays have set equality' do
+        opts = {}
+        testobj = OctocatalogDiff::CatalogDiff::Differ.new(opts, @c1, @c2)
+        testobj.ignore(type: 'Myres', title: 'res1', attr: "parameters\fset1=s>=")
+        result = testobj.diff
+        expect(OctocatalogDiff::Spec.array_contains_partial_array?(result, @set1)).to eq(false)
+        expect(OctocatalogDiff::Spec.array_contains_partial_array?(result, @set2)).to eq(true)
+        expect(OctocatalogDiff::Spec.array_contains_partial_array?(result, @set3)).to eq(true)
+      end
+
+      it 'should not filter out a change when two arrays are not equivalent sets' do
+        opts = {}
+        testobj = OctocatalogDiff::CatalogDiff::Differ.new(opts, @c1, @c2)
+        testobj.ignore(type: 'Myres', title: 'res1', attr: "parameters\fset2=s>=")
+        result = testobj.diff
+        expect(OctocatalogDiff::Spec.array_contains_partial_array?(result, @set1)).to eq(true)
+        expect(OctocatalogDiff::Spec.array_contains_partial_array?(result, @set2)).to eq(true)
+        expect(OctocatalogDiff::Spec.array_contains_partial_array?(result, @set3)).to eq(true)
+      end
+
+      it 'should not filter out a change when one array is not specified' do
+        opts = {}
+        testobj = OctocatalogDiff::CatalogDiff::Differ.new(opts, @c1, @c2)
+        testobj.ignore(type: 'Myres', title: 'res1', attr: "parameters\fset3=s>=")
+        result = testobj.diff
+        expect(OctocatalogDiff::Spec.array_contains_partial_array?(result, @set1)).to eq(true)
+        expect(OctocatalogDiff::Spec.array_contains_partial_array?(result, @set2)).to eq(true)
+        expect(OctocatalogDiff::Spec.array_contains_partial_array?(result, @set3)).to eq(true)
+      end
+    end
+  end
+
   describe '#ignore_match?' do
     let(:resource) { { type: 'Apple', title: 'delicious', attr: "parameters\fcolor" } }
     let(:testobj) { described_class.allocate }