Add associative map constraints and range refinement

crates/decodal-language-tools/src/lib.rs

@@ -169,6 +169,11 @@ impl<'a> Formatter<'a> {
                 self.write_expr(out, *item, indent, 0);
                 out.push(']');
             }
+            Expr::MapConstraint { value } => {
+                out.push_str("{...");
+                self.write_expr(out, *value, indent, 0);
+                out.push('}');
+            }
             Expr::Let { bindings, body } => self.write_let(out, node.span, bindings, *body, indent),
             Expr::Import(_) => {
                 out.push_str("import ");
@@ -219,6 +224,11 @@ impl<'a> Formatter<'a> {
                 out.push_str(" default ");
                 self.write_expr(out, *fallback, indent, precedence + 1);
             }
+            Expr::As { narrower, wider } => {
+                self.write_expr(out, *narrower, indent, precedence);
+                out.push_str(" as ");
+                self.write_expr(out, *wider, indent, precedence + 1);
+            }
             Expr::CompareConstraint { op, value } => {
                 out.push_str(compare_operator(*op));
                 out.push(' ');
@@ -461,6 +471,7 @@ impl<'a> Formatter<'a> {
 
     fn precedence(&self, id: ExprId) -> u8 {
         match &self.ast.get(id).expr {
+            Expr::As { .. } => 0,
             Expr::Default { .. } => 1,
             Expr::Binary { op, .. } => match op {
                 BinaryOp::Patch => 3,
@@ -508,7 +519,11 @@ impl<'a> Formatter<'a> {
             }
             Expr::Array(items) => items.iter().all(|item| self.is_inline_expr(*item)),
             Expr::ArrayConstraint { item } => self.is_inline_expr(*item),
+            Expr::MapConstraint { value } => self.is_inline_expr(*value),
             Expr::Parenthesized { expr } => self.is_inline_expr(*expr),
+            Expr::As { narrower, wider } => {
+                self.is_inline_expr(*narrower) && self.is_inline_expr(*wider)
+            }
             Expr::Object(_) | Expr::Let { .. } | Expr::Function { .. } | Expr::Match { .. } => {
                 false
             }
@@ -670,6 +685,18 @@ mod tests {
         );
     }
 
+    #[test]
+    fn formats_map_constraints_and_range_ascription() {
+        let source =
+            "config={service={port=8080;};}as{service={port=Int;};};labels={a=1;b=2;}as{...Int};";
+        let formatted = format_source(source).unwrap();
+        assert_eq!(
+            formatted,
+            "config = {\n    service = {\n        port = 8080;\n    };\n} as {\n    service = {\n        port = Int;\n    };\n};\nlabels = {\n    a = 1;\n    b = 2;\n} as {...Int};\n"
+        );
+        assert_eq!(format_source(&formatted).unwrap(), formatted);
+    }
+
     #[test]
     fn formats_let_functions_and_precedence_from_the_canonical_ast() {
         let source = "value=let x=1+2*3;in(a:Int)=>{result=(x+a)*2;};";
@@ -743,6 +770,10 @@ mod tests {
                 include_str!("../../../examples/import/schema.dcdl"),
             ),
             ("logical", include_str!("../../../examples/logical.dcdl")),
+            (
+                "map-ascription",
+                include_str!("../../../examples/map-ascription.dcdl"),
+            ),
             (
                 "regex/main",
                 include_str!("../../../examples/regex/main.dcdl"),