crystal-lang · Jul 26, 2016 · Jul 26, 2016
Showing with 33 additions and 6 deletions.

+22 −0 spec/compiler/codegen/c_struct_spec.cr

+11 −3 src/compiler/crystal/codegen/codegen.cr

+0 −3 src/compiler/crystal/syntax/to_s.cr
diff --git a/spec/compiler/codegen/c_struct_spec.cr b/spec/compiler/codegen/c_struct_spec.cr
@@ -357,4 +357,26 @@ describe "Code gen: struct" do
       foo.x
       )).to_i.should eq(123)
   end
+
+  it "sets instance var to proc" do
+    run(%(
+      require "prelude"
+
+      lib LibFoo
+        struct Foo
+          x : Int32 -> Int32
+        end
+      end
+
+      struct LibFoo::Foo
+        def set(f)
+          @x = f
+        end
+      end
+
+      foo = LibFoo::Foo.new
+      foo.set(->(x : Int32) { x + 1 })
+      foo.x.call(1)
+      )).to_i.should eq(2)
+  end
 end
diff --git a/src/compiler/crystal/codegen/codegen.cr b/src/compiler/crystal/codegen/codegen.cr
@@ -892,17 +892,25 @@ module Crystal
             end
 
       @last = last
+      llvm_value = last
+
+      # When setting an instance variable of an extern type, if it's a Proc
+      # type we need to check that the value is not a closure and just get
+      # the function pointer
+      if target.is_a?(InstanceVar) && context.type.extern? && target.type.proc?
+        llvm_value = check_proc_is_not_closure(llvm_value, target.type)
+      end
 
       if target.is_a?(Var) && target.special_var? && !target_type.reference_like?
         # For special vars that are not reference-like, the function argument will
         # be a pointer to the struct value. So, we need to first cast the value to
         # that type (without the pointer), load it, and store it in the argument.
         # If it's a reference-like then it's just a pointer and we can reuse the
         # logic in the other branch.
-        upcasted_value = upcast @last, target_type, value.type
-        store load(upcasted_value), ptr
+        llvm_value = upcast llvm_value, target_type, value.type
+        store load(llvm_value), ptr
       else
-        assign ptr, target_type, value.type, @last
+        assign ptr, target_type, value.type, llvm_value
       end
 
       false

diff --git a/src/compiler/crystal/syntax/to_s.cr b/src/compiler/crystal/syntax/to_s.cr
@@ -20,7 +20,6 @@ module Crystal
       @indent = 0
       @inside_macro = 0
       @inside_lib = false
-      @inside_c_struct = false
     end
 
     def visit(node : Nop)
@@ -1101,9 +1100,7 @@ module Crystal
       @str << " "
       @str << node.name.to_s
       newline
-      @inside_c_struct = true
       accept_with_indent node.body
-      @inside_c_struct = false
       append_indent
       @str << keyword("end")
       false