From dca09811c129839a74799c12f5f9192d5257bc71 Mon Sep 17 00:00:00 2001
From: rvcas <x@rvcas.dev>
Date: Thu, 31 Aug 2023 17:39:38 -0400
Subject: [PATCH] fix: empty records crashing code gen closes #728

---
 .../src/parser/definition/data_type.rs        | 49 +++++++++++++++----
 .../snapshots/empty_record_sugar.snap         | 24 +++++++++
 .../definition/snapshots/record_sugar.snap    | 39 +++++++++++++++
 3 files changed, 103 insertions(+), 9 deletions(-)
 create mode 100644 crates/aiken-lang/src/parser/definition/snapshots/empty_record_sugar.snap
 create mode 100644 crates/aiken-lang/src/parser/definition/snapshots/record_sugar.snap

diff --git a/crates/aiken-lang/src/parser/definition/data_type.rs b/crates/aiken-lang/src/parser/definition/data_type.rs
index dfea21d3..1137481f 100644
--- a/crates/aiken-lang/src/parser/definition/data_type.rs
+++ b/crates/aiken-lang/src/parser/definition/data_type.rs
@@ -54,16 +54,26 @@ pub fn parser() -> impl Parser<Token, ast::UntypedDefinition, Error = ParseError
             |(((public, opaque), (name, parameters)), constructors), span| {
                 ast::UntypedDefinition::DataType(ast::DataType {
                     location: span,
-                    constructors: constructors
-                        .into_iter()
-                        .map(|mut constructor| {
-                            if constructor.sugar {
-                                constructor.name = name.clone();
-                            }
+                    constructors: if constructors.is_empty() {
+                        vec![ast::RecordConstructor {
+                            location: span,
+                            arguments: vec![],
+                            doc: None,
+                            name: name.clone(),
+                            sugar: true,
+                        }]
+                    } else {
+                        constructors
+                            .into_iter()
+                            .map(|mut constructor| {
+                                if constructor.sugar {
+                                    constructor.name = name.clone();
+                                }
 
-                            constructor
-                        })
-                        .collect(),
+                                constructor
+                            })
+                            .collect()
+                    },
                     doc: None,
                     name,
                     opaque,
@@ -119,4 +129,25 @@ mod tests {
             "#
         );
     }
+
+    #[test]
+    fn record_sugar() {
+        assert_definition!(
+            r#"
+            pub type Foo {
+              wow: Int,
+            }
+            "#
+        );
+    }
+
+    #[test]
+    fn empty_record_sugar() {
+        assert_definition!(
+            r#"
+            pub type Foo {
+            }
+            "#
+        );
+    }
 }
diff --git a/crates/aiken-lang/src/parser/definition/snapshots/empty_record_sugar.snap b/crates/aiken-lang/src/parser/definition/snapshots/empty_record_sugar.snap
new file mode 100644
index 00000000..50c1ae14
--- /dev/null
+++ b/crates/aiken-lang/src/parser/definition/snapshots/empty_record_sugar.snap
@@ -0,0 +1,24 @@
+---
+source: crates/aiken-lang/src/parser/definition/data_type.rs
+description: "Code:\n\npub type Foo {\n}\n"
+---
+DataType(
+    DataType {
+        constructors: [
+            RecordConstructor {
+                location: 0..16,
+                name: "Foo",
+                arguments: [],
+                doc: None,
+                sugar: true,
+            },
+        ],
+        doc: None,
+        location: 0..16,
+        name: "Foo",
+        opaque: false,
+        parameters: [],
+        public: true,
+        typed_parameters: [],
+    },
+)
diff --git a/crates/aiken-lang/src/parser/definition/snapshots/record_sugar.snap b/crates/aiken-lang/src/parser/definition/snapshots/record_sugar.snap
new file mode 100644
index 00000000..d7fd3a1d
--- /dev/null
+++ b/crates/aiken-lang/src/parser/definition/snapshots/record_sugar.snap
@@ -0,0 +1,39 @@
+---
+source: crates/aiken-lang/src/parser/definition/data_type.rs
+description: "Code:\n\npub type Foo {\n  wow: Int,\n}\n"
+---
+DataType(
+    DataType {
+        constructors: [
+            RecordConstructor {
+                location: 13..28,
+                name: "Foo",
+                arguments: [
+                    RecordConstructorArg {
+                        label: Some(
+                            "wow",
+                        ),
+                        annotation: Constructor {
+                            location: 22..25,
+                            module: None,
+                            name: "Int",
+                            arguments: [],
+                        },
+                        location: 17..25,
+                        tipo: (),
+                        doc: None,
+                    },
+                ],
+                doc: None,
+                sugar: true,
+            },
+        ],
+        doc: None,
+        location: 0..28,
+        name: "Foo",
+        opaque: false,
+        parameters: [],
+        public: true,
+        typed_parameters: [],
+    },
+)