Add support for literal tuples

lib/solargraph/source/chain/array.rb

@@ -19,11 +19,12 @@ def resolve api_map, name_pin, locals
           child_types = @children.map do |child|
             child.infer(api_map, name_pin, locals)
           end
-
-          type = if child_types.uniq.length == 1 && child_types.first.defined?
+          type = if child_types.length == 0 || child_types.any?(&:undefined?)
+                   ComplexType::UniqueType.new('Array', rooted: true)
+                 elsif child_types.uniq.length == 1 && child_types.first.defined?
                    ComplexType::UniqueType.new('Array', [], child_types.uniq, rooted: true, parameters_type: :list)
                  else
-                   ComplexType::UniqueType.new('Array', rooted: true)
+                   ComplexType::UniqueType.new('Array', [], child_types, rooted: true, parameters_type: :fixed)
                  end
           [Pin::ProxyType.anonymous(type)]
         end

spec/source/source_chainer_spec.rb

@@ -283,7 +283,7 @@ class Inner2
     expect(type.tag).to eq('Array<String>')
   end
 
-  it 'infers general array type when types in literal differ' do
+  it 'infers tuple type when types in literal differ' do
     source = Solargraph::Source.load_string(%(
       ['a', 123]
     ), 'test.rb')
@@ -292,7 +292,7 @@ class Inner2
 
     chain = Solargraph::Source::SourceChainer.chain(source, Solargraph::Position.new(1, 16))
     type = chain.infer(api_map, Solargraph::Pin::ROOT_PIN, api_map.source_map('test.rb').locals)
-    expect(type.tag).to eq('Array')
+    expect(type.tag).to eq('Array(String, Integer)')
   end
 
   it 'infers specific array type when types in literal identical' do

spec/source_map/clip_spec.rb

@@ -1950,7 +1950,7 @@ def foo
   xit 'identifies tuple types' do
     source = Solargraph::Source.load_string(%(
       # @type [Array(String, Integer)]
-      a = 123
+      a = foo
       b = a[0]
       b
       c = a[1]
@@ -1987,7 +1987,7 @@ def foo
     expect(type.rooted_tags).to eq('::Array<::Integer>')
   end
 
-  xit 'infers tuple types from diverse literal arrays' do
+  it 'infers tuple types from diverse literal arrays' do
     source = Solargraph::Source.load_string(%(
       a = [123, 'foo']
       a
@@ -1998,6 +1998,39 @@ def foo
     expect(type.to_s).to eq('Array(Integer, String)')
   end
 
+  it 'infers shallow literal diverse arrays into tuples' do
+    source = Solargraph::Source.load_string(%(
+      h = ['foo', 1]
+      h
+    ), 'test.rb')
+    api_map = Solargraph::ApiMap.new.map(source)
+    clip = api_map.clip_at('test.rb', [2, 6])
+    type = clip.infer
+    expect(type.to_s).to eq('Array(String, Integer)')
+  end
+
+  it 'infers array of identical diverse arrays into tuples' do
+    source = Solargraph::Source.load_string(%(
+      h = [['foo', 1], ['bar', 2]]
+      h
+    ), 'test.rb')
+    api_map = Solargraph::ApiMap.new.map(source)
+    clip = api_map.clip_at('test.rb', [2, 6])
+    type = clip.infer
+    expect(type.to_s).to eq('Array<Array(String, Integer)>')
+  end
+
+  it 'infers literal diverse array of diverse arrays into tuple of tuples' do
+    source = Solargraph::Source.load_string(%(
+      h = [['foo', 1], ['bar', :baz]]
+      h
+    ), 'test.rb')
+    api_map = Solargraph::ApiMap.new.map(source)
+    clip = api_map.clip_at('test.rb', [2, 6])
+    type = clip.infer
+    expect(type.to_s).to eq('Array(Array(String, Integer), Array(String, Symbol))')
+  end
+
   it 'resolves block parameter types from Hash#each' do
     source = Solargraph::Source.load_string(%(
       # @type [Hash{String => Integer}]
@@ -2044,17 +2077,6 @@ def foo
     expect(type.to_s).to eq('Integer')
   end
 
-  xit 'infers literal heterogeneous arrays into tuples' do
-    source = Solargraph::Source.load_string(%(
-      h = [['foo', 1], ['bar', 2]]
-      h
-    ), 'test.rb')
-    api_map = Solargraph::ApiMap.new.map(source)
-    clip = api_map.clip_at('test.rb', [2, 6])
-    type = clip.infer
-    expect(type.to_s).to eq('Array<Array(String, Integer)>')
-  end
-
   it 'excludes Kernel singleton methods from chained methods' do
     source = Solargraph::Source.load_string('[].put', 'test.rb')
     api_map = Solargraph::ApiMap.new.map(source)