Implement arguments case equality

Implements https://github.com/icy-arctic-fox/spectator/issues/47
Some specs are failing and need to be resolved before the new feature is considered done.

spec/issues/github_issue_47_spec.cr

@@ -11,7 +11,7 @@ Spectator.describe "GitHub Issue #47" do
 
   let(fake) { mock(Original) }
 
-  xspecify do
+  specify do
     expect(fake).to receive(:foo).with("arg1", arg2: "arg2")
     fake.foo("arg1", "arg2")
   end

spec/spectator/mocks/arguments_spec.cr

@@ -20,18 +20,61 @@ Spectator.describe Spectator::Arguments do
     end
   end
 
-  describe "#[]" do
-    context "with an index" do
+  describe "#[](index)" do
+    it "returns a positional argument" do
+      aggregate_failures do
+        expect(arguments[0]).to eq(42)
+        expect(arguments[1]).to eq("foo")
+      end
+    end
+
+    it "returns splat arguments" do
+      aggregate_failures do
+        expect(arguments[2]).to eq(:x)
+        expect(arguments[3]).to eq(:y)
+        expect(arguments[4]).to eq(:z)
+      end
+    end
+
+    context "with named positional arguments" do
+      subject(arguments) { Spectator::Arguments.new({arg1: 42, arg2: "foo"}, :splat, {:x, :y, :z}, {bar: "baz", qux: 123}) }
+
       it "returns a positional argument" do
         aggregate_failures do
           expect(arguments[0]).to eq(42)
           expect(arguments[1]).to eq("foo")
         end
       end
+
+      it "returns splat arguments" do
+        aggregate_failures do
+          expect(arguments[2]).to eq(:x)
+          expect(arguments[3]).to eq(:y)
+          expect(arguments[4]).to eq(:z)
+        end
+      end
+    end
+  end
+
+  describe "#[](symbol)" do
+    it "returns a keyword argument" do
+      aggregate_failures do
+        expect(arguments[:bar]).to eq("baz")
+        expect(arguments[:qux]).to eq(123)
+      end
     end
 
-    context "with a symbol" do
-      it "returns a named argument" do
+    context "with named positional arguments" do
+      subject(arguments) { Spectator::Arguments.new({arg1: 42, arg2: "foo"}, :splat, {:x, :y, :z}, {bar: "baz", qux: 123}) }
+
+      it "returns a positional argument" do
+        aggregate_failures do
+          expect(arguments[:arg1]).to eq(42)
+          expect(arguments[:arg2]).to eq("foo")
+        end
+      end
+
+      it "returns a keyword argument" do
         aggregate_failures do
           expect(arguments[:bar]).to eq("baz")
           expect(arguments[:qux]).to eq(123)
@@ -62,33 +105,57 @@ Spectator.describe Spectator::Arguments do
     context "with equal arguments" do
       let(other) { arguments }
 
-      it "returns true" do
-        is_expected.to be_true
-      end
+      it { is_expected.to be_true }
     end
 
     context "with different arguments" do
-      let(other) { Spectator::Arguments.new({123, :foo, "bar"}, nil, nil, {opt: "foobar"}) }
+      let(other) { Spectator::Arguments.new({123, :foo, "bar"}, :splat, {1, 2, 3}, {opt: "foobar"}) }
 
-      it "returns false" do
-        is_expected.to be_false
-      end
+      it { is_expected.to be_false }
     end
 
     context "with the same kwargs in a different order" do
-      let(other) { Spectator::Arguments.new(arguments.args, nil, nil, {qux: 123, bar: "baz"}) }
+      let(other) { Spectator::Arguments.new(arguments.args, arguments.splat_name, arguments.splat, {qux: 123, bar: "baz"}) }
 
-      it "returns true" do
-        is_expected.to be_true
-      end
+      it { is_expected.to be_true }
     end
 
     context "with a missing kwarg" do
-      let(other) { Spectator::Arguments.new(arguments.args, nil, nil, {bar: "baz"}) }
+      let(other) { Spectator::Arguments.new(arguments.args, arguments.splat_name, arguments.splat, {bar: "baz"}) }
 
-      it "returns false" do
-        is_expected.to be_false
-      end
+      it { is_expected.to be_false }
+    end
+
+    context "with an extra kwarg" do
+      let(other) { Spectator::Arguments.new(arguments.args, arguments.splat_name, arguments.splat, {bar: "baz", qux: 123, extra: 0}) }
+
+      it { is_expected.to be_false }
+    end
+
+    context "with different splat arguments" do
+      let(other) { Spectator::Arguments.new(arguments.args, arguments.splat_name, {1, 2, 3}, arguments.kwargs) }
+
+      it { is_expected.to be_false }
+    end
+
+    context "with mixed positional tuple types" do
+      let(other) { Spectator::Arguments.new({arg1: 42, arg2: "foo"}, arguments.splat_name, arguments.splat, arguments.kwargs) }
+
+      it { is_expected.to be_true }
+    end
+
+    context "with mixed positional tuple types (flipped)" do
+      let(arguments) { Spectator::Arguments.new({arg1: 42, arg2: "foo"}, :splat, {:x, :y, :z}, {bar: "baz", qux: 123}) }
+      let(other) { Spectator::Arguments.new({42, "foo"}, :splat, {:x, :y, :z}, {bar: "baz", qux: 123}) }
+
+      it { is_expected.to be_true }
+    end
+
+    context "with args spilling over into splat and mixed positional tuple types" do
+      let(arguments) { Spectator::Arguments.new({arg1: 42, arg2: "foo"}, :splat, {:x, :y, :z}, {bar: "baz", qux: 123}) }
+      let(other) { Spectator::Arguments.new({42, "foo", :x, :y, :z}, nil, nil, {bar: "baz", qux: 123}) }
+
+      it { is_expected.to be_true }
     end
   end
 
@@ -98,49 +165,96 @@ Spectator.describe Spectator::Arguments do
     context "with equal arguments" do
       let(pattern) { arguments }
 
-      it "returns true" do
-        is_expected.to be_true
-      end
+      it { is_expected.to be_true }
+    end
+
+    context "with matching arguments" do
+      let(pattern) { Spectator::Arguments.new({Int32, /foo/}, :splat, {Symbol, Symbol, :z}, {bar: /baz/, qux: Int32}) }
+
+      it { is_expected.to be_true }
+    end
+
+    context "with non-matching arguments" do
+      let(pattern) { Spectator::Arguments.new({Float64, /bar/}, :splat, {String, Int32, :x}, {bar: /foo/, qux: "123"}) }
+
+      it { is_expected.to be_false }
     end
 
     context "with different arguments" do
-      let(pattern) { Spectator::Arguments.new({123, :foo, "bar"}, nil, nil, {opt: "foobar"}) }
+      let(pattern) { Spectator::Arguments.new({123, :foo, "bar"}, :splat, {1, 2, 3}, {opt: "foobar"}) }
 
-      it "returns false" do
-        is_expected.to be_false
-      end
+      it { is_expected.to be_false }
     end
 
     context "with the same kwargs in a different order" do
-      let(pattern) { Spectator::Arguments.new(arguments.args, nil, nil, {qux: 123, bar: "baz"}) }
+      let(pattern) { Spectator::Arguments.new(arguments.args, arguments.splat_name, arguments.splat, {qux: Int32, bar: /baz/}) }
 
-      it "returns true" do
-        is_expected.to be_true
-      end
+      it { is_expected.to be_true }
+    end
+
+    context "with an additional kwarg" do
+      let(pattern) { Spectator::Arguments.new(arguments.args, arguments.splat_name, arguments.splat, {bar: /baz/}) }
+
+      it { is_expected.to be_true }
     end
 
     context "with a missing kwarg" do
-      let(pattern) { Spectator::Arguments.new(arguments.args, nil, nil, {bar: "baz"}) }
+      let(pattern) { Spectator::Arguments.new(arguments.args, arguments.splat_name, arguments.splat, {bar: /baz/, qux: Int32, extra: 0}) }
 
-      it "returns false" do
-        is_expected.to be_false
-      end
+      it { is_expected.to be_false }
     end
 
-    context "with matching types and regex" do
-      let(pattern) { Spectator::Arguments.new({Int32, /foo/}, nil, nil, {bar: String, qux: 123}) }
+    context "with different splat arguments" do
+      let(pattern) { Spectator::Arguments.new(arguments.args, arguments.splat_name, {1, 2, 3}, arguments.kwargs) }
 
-      it "returns true" do
-        is_expected.to be_true
-      end
+      it { is_expected.to be_false }
     end
 
-    context "with different types and regex" do
-      let(pattern) { Spectator::Arguments.new({Symbol, /bar/}, nil, nil, {bar: String, qux: 42}) }
+    context "with matching mixed positional tuple types" do
+      let(pattern) { Spectator::Arguments.new({arg1: Int32, arg2: /foo/}, arguments.splat_name, arguments.splat, arguments.kwargs) }
 
-      it "returns false" do
-        is_expected.to be_false
-      end
+      it { is_expected.to be_true }
+    end
+
+    context "with non-matching mixed positional tuple types" do
+      let(pattern) { Spectator::Arguments.new({arg1: Float64, arg2: /bar/}, arguments.splat_name, arguments.splat, arguments.kwargs) }
+
+      it { is_expected.to be_false }
+    end
+
+    context "with matching args spilling over into splat and mixed positional tuple types" do
+      let(arguments) { Spectator::Arguments.new({arg1: 42, arg2: "foo"}, :splat, {:x, :y, :z}, {bar: "baz", qux: 123}) }
+      let(pattern) { Spectator::Arguments.capture(Int32, /foo/, Symbol, Symbol, :z, bar: /baz/, qux: Int32) }
+
+      it { is_expected.to be_true }
+    end
+
+    context "with non-matching args spilling over into splat and mixed positional tuple types" do
+      let(arguments) { Spectator::Arguments.new({arg1: 42, arg2: "foo"}, :splat, {:x, :y, :z}, {bar: "baz", qux: 123}) }
+      let(pattern) { Spectator::Arguments.capture(Float64, /bar/, Symbol, String, :z, bar: /foo/, qux: Int32) }
+
+      it { is_expected.to be_false }
+    end
+
+    context "with matching mixed named positional and keyword arguments" do
+      let(arguments) { Spectator::Arguments.new({arg1: 42, arg2: "foo"}, :splat, {:x, :y, :z}, {bar: "baz", qux: 123}) }
+      let(pattern) { Spectator::Arguments.capture(/foo/, Symbol, :y, Symbol, arg1: Int32, bar: /baz/, qux: 123) }
+
+      it { is_expected.to be_true }
+    end
+
+    context "with non-matching mixed named positional and keyword arguments" do
+      let(arguments) { Spectator::Arguments.new({arg1: 42, arg2: "foo"}, :splat, {:x, :y, :z}, {bar: "baz", qux: 123}) }
+      let(pattern) { Spectator::Arguments.capture(5, Symbol, :z, Symbol, arg2: /foo/, bar: /baz/, qux: Int32) }
+
+      it { is_expected.to be_false }
+    end
+
+    context "with non-matching mixed named positional and keyword arguments" do
+      let(arguments) { Spectator::Arguments.new({arg1: 42, arg2: "foo"}, :splat, {:x, :y, :z}, {bar: "baz", qux: 123}) }
+      let(pattern) { Spectator::Arguments.capture(/bar/, String, :y, Symbol, arg1: 0, bar: /foo/, qux: Float64) }
+
+      it { is_expected.to be_false }
     end
   end
 end

src/spectator/mocks/arguments.cr

@@ -74,6 +74,15 @@ module Spectator
       end
     end
 
+    # Returns all named positional and keyword arguments as a named tuple.
+    def named : NamedTuple
+      {% if Args < NamedTuple %}
+        args.merge(kwargs)
+      {% else %}
+        kwargs
+      {% end %}
+    end
+
     # Constructs a string representation of the arguments.
     def to_s(io : IO) : Nil
       return io << "(no args)" if args.empty? && ((splat = @splat).nil? || splat.empty?) && kwargs.empty?
@@ -127,31 +136,48 @@ module Spectator
 
     # Checks if another set of arguments matches this set of arguments.
     def ===(other : Arguments)
-      {% if Args < NamedTuple %}
-        if (other_args = other.args).is_a?(NamedTuple)
-          args.each do |k, v|
-            return false unless other_args.has_key?(k)
-            return false unless v === other_args[k]
-          end
-        else
-          return false if args.size != other_args
-          args.each_with_index do |k, v, i|
-            return false unless v === other_args.unsafe_fetch(i)
-          end
-        end
-      {% else %}
-        return false unless args === other.positional
-      {% end %}
+      self_args = args
+      other_args = other.args
 
-      if splat = @splat
-        return false unless splat === other.splat
+      case {self_args, other_args}
+      when {Tuple, Tuple}      then compare(positional, other.positional, kwargs, other.kwargs)
+      when {Tuple, NamedTuple} then compare(kwargs, other.named, positional, other_args, other.splat)
+      when {NamedTuple, Tuple} then compare(positional, other.positional, kwargs, other.kwargs)
+      else
+        self_args === other_args && (!splat || splat === other.splat) && compare_named_tuples(kwargs, other.kwargs)
+      end
+    end
+
+    private def compare(self_positional : Tuple, other_positional : Tuple, self_kwargs : NamedTuple, other_kwargs : NamedTuple)
+      self_positional === other_positional && compare_named_tuples(self_kwargs, other_kwargs)
+    end
+
+    private def compare(self_kwargs : NamedTuple, other_named : NamedTuple, self_positional : Tuple, other_args : NamedTuple, other_splat : Tuple?)
+      return false unless compare_named_tuples(self_kwargs, other_named)
+
+      i = 0
+      other_args.each do |k, v2|
+        next if self_kwargs.has_key?(k) # Covered by named arguments.
+
+        v1 = self_positional.fetch(i) { return false }
+        i += 1
+        return false unless v1 === v2
       end
 
-      kwargs.each do |k, v|
-        return false unless other.kwargs.has_key?(k)
-        return false unless v === other.kwargs[k]
+      other_splat.try &.each do |v2|
+        v1 = self_positional.fetch(i) { return false }
+        i += 1
+        return false unless v1 === v2
       end
 
+      i == self_positional.size
+    end
+
+    private def compare_named_tuples(a : NamedTuple, b : NamedTuple)
+      a.each do |k, v1|
+        v2 = b.fetch(k) { return false }
+        return false unless v1 === v2
+      end
       true
     end
   end