Fix empty struct

Signed-off-by: Kristupas Antanavičius <[email protected]>

bindgen/templates/RecordTemplate.cs

@@ -55,9 +55,9 @@ class {{ rec|ffi_converter_name }}: FfiConverterRustBuffer<{{ type_name }}> {
     }
 
     public override int AllocationSize({{ type_name }} value) {
-        return
+        return 0
         {%- for field in rec.fields() %}
-            {{ field|allocation_size_fn }}(value.{{ field.name()|var_name }}){% if !loop.last %} +{% endif%}
+            + {{ field|allocation_size_fn }}(value.{{ field.name()|var_name }})
         {%- endfor -%};
     }
 

dotnet-tests/UniffiCS.BindingTests/TestIssue75.cs

@@ -0,0 +1,16 @@
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this
+// file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+using uniffi.issue_75;
+
+namespace UniffiCS.BindingTests;
+
+public class ClassIssue75
+{
+    [Fact]
+    public void TestIssue75()
+    {
+        new uniffi.issue_75.EmptyDictionary();
+    }
+}

dotnet-tests/UniffiCS.BindingTests/TestRegressions.cs → dotnet-tests/UniffiCS.BindingTests/TestIssue76.cs

@@ -6,7 +6,7 @@
 
 namespace UniffiCS.BindingTests;
 
-public class TestRegressions
+public class ClassIssue76
 {
     [Fact]
     public void TestIssue76()

fixtures/Cargo.toml

@@ -10,6 +10,7 @@ crate-type = ["cdylib", "lib"]
 
 [dependencies]
 global-methods-class-name = { path = "global-methods-class-name" }
+issue-75 = { path = "regressions/issue-75" }
 issue-76 = { path = "regressions/issue-76" }
 null-to-empty-string = { path = "null-to-empty-string" }
 uniffi-cs-custom-types-builtin = { path = "custom-types-builtin" }

fixtures/regressions/issue-75/Cargo.toml

@@ -0,0 +1,18 @@
+[package]
+name = "issue-75"
+version = "1.0.0"
+edition = "2021"
+publish = false
+
+[lib]
+crate-type = ["lib", "cdylib"]
+name = "issue_75"
+
+[dependencies]
+once_cell = "1.12"
+thiserror = "1.0"
+uniffi = {path = "../../../3rd-party/uniffi-rs/uniffi", features=["build"]}
+uniffi_macros = {path = "../../../3rd-party/uniffi-rs/uniffi_macros"}
+
+[build-dependencies]
+uniffi = {path = "../../../3rd-party/uniffi-rs/uniffi", features=["bindgen-tests"]}

fixtures/regressions/issue-75/README.md

@@ -0,0 +1,3 @@
+# https://github.com/NordSecurity/uniffi-bindgen-cs/issues/75
+
+Empty struct causes invalid code to be generated in `RecordTemplate.cs::AllocationSize`

fixtures/regressions/issue-75/src/lib.rs

@@ -0,0 +1,9 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#[derive(uniffi::Record)]
+pub struct EmptyDictionary {
+}
+
+uniffi::setup_scaffolding!();

fixtures/src/lib.rs

@@ -23,5 +23,6 @@ mod uniffi_fixtures {
     uniffi_cs_disposable::uniffi_reexport_scaffolding!();
     uniffi_cs_optional_parameters::uniffi_reexport_scaffolding!();
     stringify::uniffi_reexport_scaffolding!();
+    issue_75::uniffi_reexport_scaffolding!();
     issue_76::uniffi_reexport_scaffolding!();
 }