Merge pull request #1459 from soutaro/when-annotation

Let annotations in `when` clause without `cond` expression work
soutaro · Jan 7, 2025 · 9d9c88e · 9d9c88e
2 parents 7ba1260 + 9e946eb
commit 9d9c88e
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Showing 3 changed files with 31 additions and 1 deletion.
diff --git a/lib/steep/type_construction.rb b/lib/steep/type_construction.rb
@@ -2026,8 +2026,8 @@ def synthesize(node, hint: nil, condition: false)
                 branch_result =
                   if body
                     when_clause_constr
-                      .for_branch(body)
                       .update_type_env {|env| env.join(*body_envs) }
+                      .for_branch(body)
                       .tap {|constr| typing.cursor_context.set_node_context(body, constr.context) }
                       .synthesize(body, hint: hint)
                   else

diff --git a/sig/test/type_check_test.rbs b/sig/test/type_check_test.rbs
@@ -181,4 +181,6 @@ class TypeCheckTest < Minitest::Test
   def test_undeclared_method2: () -> untyped
 
   def test_when__assertion: () -> untyped
+
+  def test_when__type_annotation: () -> untyped
 end
diff --git a/test/type_check_test.rb b/test/type_check_test.rb
@@ -2869,4 +2869,32 @@ def test_when__assertion
       YAML
     )
   end
+
+  def test_when__type_annotation
+    run_type_check_test(
+      signatures: {
+        "a.rbs" => <<~RBS
+        RBS
+      },
+      code: {
+        "a.rb" => <<~RUBY
+          a = [1, ""].sample
+
+          case
+          when 1.even?
+            # @type var a: String
+            a + ""
+          when 2.even?
+            # @type var a: Integer
+            a + 1
+          end
+        RUBY
+      },
+      expectations: <<~YAML
+        ---
+        - file: a.rb
+          diagnostics: []
+      YAML
+    )
+  end
 end