fix(compiler): confusing error when trying to use private constructor

docs/docs/03-language-reference.md

@@ -642,7 +642,7 @@ let handler2 = inflight() => {
 Bridge between preflight and inflight is crossed with the help of immutable data
 structures, "structs" (user definable and `Struct`), and the capture mechanism.
 
-Preflight class methods and initializers can receive an inflight function as an argument. This
+Preflight class methods and constructors can receive an inflight function as an argument. This
 enables preflight classes to define code that will be executed on a cloud compute platform such as
 lambda functions, docker, virtual machines etc.
 

examples/jsii-fixture/src/index.ts

@@ -31,6 +31,14 @@ export class JsiiClass {
   }
 }
 
+export class JsiiClassWithPrivateConstructor {
+  private constructor() {}
+
+  public static makeInstance(): JsiiClassWithPrivateConstructor {
+    return new JsiiClassWithPrivateConstructor();
+  }
+}
+
 /**
  * @callable
  */
@@ -47,4 +55,4 @@ export interface SomeStruct {
 
 export interface ISomeInterface {
   method(): void;
-}
+}

examples/tests/invalid/class.test.w

@@ -158,7 +158,7 @@ inflight class Jet extends Plane{
 //  ^^^^^^^^ Expected 1 positional argument(s) but got 0
   }
   constructor() {
-//^^^^^^^^^^^ To declare a initializer, use "init"
+//^^^^^^^^^^^ To declare a constructor, use "new"
   }
 }
 

examples/tests/invalid/inflight_class_dup_init.test.w

@@ -6,5 +6,5 @@ inflight class Foo {
   inflight new() {
 
   }
-//^ Multiple inflight initializers defined in class Foo
+//^ Multiple inflight constructors defined in class Foo
 }

examples/tests/invalid/private_constructor.test.w

@@ -0,0 +1,6 @@
+bring "jsii-fixture" as jsii_fixture;
+
+new jsii_fixture.JsiiClassWithPrivateConstructor();
+// error: constructor is private and only accessible within class "JsiiClassWithPrivateConstructor"
+
+jsii_fixture.JsiiClassWithPrivateConstructor.makeInstance(); // OK

libs/wingc/src/parser.rs

@@ -115,7 +115,6 @@ static RESERVED_WORDS: phf::Set<&'static str> = phf_set! {
 	"inflight",
 	"preflight",
 	"elif",
-	"init",
 	"any",
 	"num",
 	"str",
@@ -1228,14 +1227,14 @@ impl<'s> Parser<'s> {
 					if initializer.is_some() && !is_inflight {
 						self
 							.with_error::<Node>(
-								format!("Multiple initializers defined in class {}", name.name),
+								format!("Multiple constructors defined in class {}", name.name),
 								&class_element,
 							)
 							.err();
 					} else if inflight_initializer.is_some() && is_inflight {
 						self
 							.with_error::<Node>(
-								format!("Multiple inflight initializers defined in class {}", name.name),
+								format!("Multiple inflight constructors defined in class {}", name.name),
 								&class_element,
 							)
 							.err();
@@ -1244,7 +1243,7 @@ impl<'s> Parser<'s> {
 					let parameters = self.build_parameter_list(&parameters_node, class_phase, false)?;
 					if !parameters.is_empty() && is_inflight && class_phase == Phase::Preflight {
 						self
-							.with_error::<Node>("Inflight initializers cannot have parameters", &parameters_node)
+							.with_error::<Node>("Inflight constructors cannot have parameters", &parameters_node)
 							.err();
 					}
 
@@ -1303,7 +1302,7 @@ impl<'s> Parser<'s> {
 		for method in &methods {
 			if method.0.name == "constructor" {
 				Diagnostic::new(
-					"Reserved method name. Initializers are declared with \"init\"",
+					"Reserved method name. Constructors are declared with a method named \"new\"",
 					&method.0,
 				)
 				.report();

libs/wingc/src/type_check.rs

@@ -250,7 +250,7 @@ pub enum Type {
 	Enum(Enum),
 }
 
-pub const CLASS_INIT_NAME: &'static str = "init";
+pub const CLASS_INIT_NAME: &'static str = "new";
 pub const CLASS_INFLIGHT_INIT_NAME: &'static str = "$inflight_init";
 
 pub const CLOSURE_CLASS_HANDLE_METHOD: &'static str = "handle";
@@ -2314,17 +2314,28 @@ impl<'a> TypeChecker<'a> {
 					};
 
 					let lookup_res = class_env.lookup_ext(&init_method_name.into(), None);
-					let constructor_type = if let LookupResult::Found(k, _) = lookup_res {
-						k.as_variable().expect("Expected constructor to be a variable").type_
-					} else {
-						self.type_error(lookup_result_to_type_error(
-							lookup_res,
-							&Symbol {
-								name: CLASS_INIT_NAME.into(),
-								span: class_symbol.span.clone(),
-							},
-						));
-						return self.resolved_error();
+					let constructor_type = match lookup_res {
+						LookupResult::Found(k, _) => k.as_variable().expect("Expected constructor to be a variable").type_,
+						LookupResult::NotFound(_, _) => {
+							self.spanned_error(
+								exp,
+								format!("Constructor for class \"{}\" is private", class_symbol.name),
+							);
+							return self.resolved_error();
+						}
+						LookupResult::NotPublic(_, _)
+						| LookupResult::MultipleFound
+						| LookupResult::DefinedLater(_)
+						| LookupResult::ExpectedNamespace(_) => {
+							self.type_error(lookup_result_to_type_error(
+								lookup_res,
+								&Symbol {
+									name: CLASS_INIT_NAME.into(),
+									span: class_symbol.span.clone(),
+								},
+							));
+							return self.resolved_error();
+						}
 					};
 					let constructor_sig = constructor_type
 						.as_function_sig()
@@ -4798,7 +4809,7 @@ impl<'a> TypeChecker<'a> {
 			return;
 		};
 
-		// If the parent class is phase independent than its init name is just "init" regadless of
+		// If the parent class is phase independent than its constructor name is just "new" regardless of
 		// whether we're inflight or not.
 		let parent_init_name = if parent_class.as_class().unwrap().phase == Phase::Independent {
 			CLASS_INIT_NAME
@@ -4851,7 +4862,7 @@ impl<'a> TypeChecker<'a> {
 					self.spanned_error(
 						matching_field,
 						format!(
-							"\"{}\" cannot be initialized in the {} initializer",
+							"\"{}\" cannot be initialized in the {} constructor",
 							matching_field.name,
 							current_phase.to_lowercase()
 						),

libs/wingc/src/type_check/jsii_importer.rs

@@ -773,7 +773,7 @@ impl<'a> JsiiImporter<'a> {
 		let mut class_env = SymbolEnv::new(base_class_env, SymbolEnvKind::Type(new_type), class_phase, 0);
 		class_env.type_parameters = self.type_param_from_docs(&jsii_class_fqn, &jsii_class.docs);
 
-		// Add constructor to the class environment
+		// Add the class's constructor to the class environment, if the class has one which is public
 		let jsii_initializer = jsii_class.initializer.as_ref();
 		if let Some(initializer) = jsii_initializer {
 			let mut fn_params = vec![];

tools/hangar/__snapshots__/invalid.ts.snap

@@ -747,11 +747,11 @@ error: Call to super constructor can only be done from within a class constructo
     |    ^^^^^^^^ Call to super constructor can only be done from within a class constructor
 
 
-error: Reserved method name. Initializers are declared with \\"init\\"
+error: Reserved method name. Constructors are declared with a method named \\"new\\"
     --> ../../../examples/tests/invalid/class.test.w:160:3
     |
 160 |   constructor() {
-    |   ^^^^^^^^^^^ Reserved method name. Initializers are declared with \\"init\\"
+    |   ^^^^^^^^^^^ Reserved method name. Constructors are declared with a method named \\"new\\"
 
 
 error: Expected block
@@ -838,18 +838,18 @@ error: Inflight field \\"x\\" is not initialized
    |            ^ Inflight field \\"x\\" is not initialized
 
 
-error: \\"y\\" cannot be initialized in the inflight initializer
+error: \\"y\\" cannot be initialized in the inflight constructor
    --> ../../../examples/tests/invalid/class.test.w:61:10
    |
 61 |     this.y = 1;
-   |          ^ \\"y\\" cannot be initialized in the inflight initializer
+   |          ^ \\"y\\" cannot be initialized in the inflight constructor
 
 
-error: \\"x\\" cannot be initialized in the preflight initializer
+error: \\"x\\" cannot be initialized in the preflight constructor
    --> ../../../examples/tests/invalid/class.test.w:56:10
    |
 56 |     this.x = 1;
-   |          ^ \\"x\\" cannot be initialized in the preflight initializer
+   |          ^ \\"x\\" cannot be initialized in the preflight constructor
 
 
 error: Preflight field \\"y\\" is not initialized
@@ -2259,13 +2259,13 @@ Duration <DURATION>"
 `;
 
 exports[`inflight_class_dup_init.test.w 1`] = `
-"error: Multiple inflight initializers defined in class Foo
+"error: Multiple inflight constructors defined in class Foo
   --> ../../../examples/tests/invalid/inflight_class_dup_init.test.w:6:3
   |  
 6 | /   inflight new() {
 7 | | 
 8 | |   }
-  | \\\\---^ Multiple inflight initializers defined in class Foo
+  | \\\\---^ Multiple inflight constructors defined in class Foo
 
 
 
@@ -3249,6 +3249,21 @@ error: Expected type to be \\"str\\", but got \\"num\\" instead
 
 
 
+Tests 1 failed (1)
+Snapshots 1 skipped
+Test Files 1 failed (1)
+Duration <DURATION>"
+`;
+
+exports[`private_constructor.test.w 1`] = `
+"error: Constructor for class \\"JsiiClassWithPrivateConstructor\\" is private
+  --> ../../../examples/tests/invalid/private_constructor.test.w:3:1
+  |
+3 | new jsii_fixture.JsiiClassWithPrivateConstructor();
+  | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Constructor for class \\"JsiiClassWithPrivateConstructor\\" is private
+
+
+
 Tests 1 failed (1)
 Snapshots 1 skipped
 Test Files 1 failed (1)
@@ -3529,32 +3544,32 @@ Duration <DURATION>"
 `;
 
 exports[`resource_init.test.w 1`] = `
-"error: Multiple initializers defined in class R
+"error: Multiple constructors defined in class R
   --> ../../../examples/tests/invalid/resource_init.test.w:3:3
   |
 3 |   new() {}
-  |   ^^^^^^^^ Multiple initializers defined in class R
+  |   ^^^^^^^^ Multiple constructors defined in class R
 
 
-error: Multiple inflight initializers defined in class R
+error: Multiple inflight constructors defined in class R
   --> ../../../examples/tests/invalid/resource_init.test.w:6:3
   |
 6 |   inflight new() {}
-  |   ^^^^^^^^^^^^^^^^^ Multiple inflight initializers defined in class R
+  |   ^^^^^^^^^^^^^^^^^ Multiple inflight constructors defined in class R
 
 
-error: Multiple inflight initializers defined in class R
+error: Multiple inflight constructors defined in class R
   --> ../../../examples/tests/invalid/resource_init.test.w:9:3
   |
 9 |   inflight new(x: num) {}
-  |   ^^^^^^^^^^^^^^^^^^^^^^^ Multiple inflight initializers defined in class R
+  |   ^^^^^^^^^^^^^^^^^^^^^^^ Multiple inflight constructors defined in class R
 
 
-error: Inflight initializers cannot have parameters
+error: Inflight constructors cannot have parameters
   --> ../../../examples/tests/invalid/resource_init.test.w:9:15
   |
 9 |   inflight new(x: num) {}
-  |               ^^^^^^^^ Inflight initializers cannot have parameters
+  |               ^^^^^^^^ Inflight constructors cannot have parameters