Pipeline-overridable constants

packages/grammar/src/lib/repository/keywords.ts

@@ -8,7 +8,7 @@ export const keyword: TMGrammarScope = {
 			name: "keyword.control.$1.wgsl",
 		},
 		{
-			match: /\b(struct|fn|const|var|let|alias)\b/,
+			match: /\b(struct|fn|const|var|let|override|alias)\b/,
 			name: "storage.type.$1.wgsl",
 		},
 		{

packages/parser/snapshots/tests/decl/override_decl-001.wgsl-ast

@@ -0,0 +1,46 @@
+================================================================================
+tests::decl::override_decl / #1
+================================================================================
+(Decl::Const (VarDecl
+  attributes: (AttributeList
+    attributes: [
+      (Attribute
+        at_sign: `@` (Punct (1:1..1:2)),
+        name: `id` (Attribute (1:2..1:4)),
+        params: (ArgumentList
+          brace_open: `(` (Brace (1:4..1:5)),
+          arguments: [
+            (Expr::Primary (PrimaryExpr
+              expr: (Expr::Literal `0` (IntLiteral (1:5..1:6))),
+            )),
+          ],
+          brace_close: `)` (Brace (1:6..1:7)),
+        ),
+      ),
+    ],
+  ),
+  storage: `override` (Keyword (1:8..1:16)),
+  name: `has_point_light` (Ident (1:17..1:32)),
+  ty: (TypeDecl
+    annotator: `:` (Punct (1:32..1:33)),
+    name: (IdentExpr::Leaf `bool` (Type (1:34..1:38))),
+  ),
+  assignment: (Expr::Primary (PrimaryExpr
+    expr: (Expr::Literal `true` (Keyword (1:41..1:45))),
+  )),
+  semicolon: `;` (Punct (1:45..1:46)),
+))
+--- Tokens ---------------------------------------------------------------------
+`@` (Punct (1:1..1:2))
+`id` (Attribute (1:2..1:4))
+`(` (Brace (1:4..1:5))
+`0` (IntLiteral (1:5..1:6))
+`)` (Brace (1:6..1:7))
+`override` (Keyword (1:8..1:16))
+`has_point_light` (Ident (1:17..1:32))
+`:` (Punct (1:32..1:33))
+`bool` (Type (1:34..1:38))
+`=` (Operator (1:39..1:40))
+`true` (Keyword (1:41..1:45))
+`;` (Punct (1:45..1:46))
+================================================================================

packages/parser/snapshots/tests/decl/override_decl-002.wgsl-ast

@@ -0,0 +1,46 @@
+================================================================================
+tests::decl::override_decl / #2
+================================================================================
+(Decl::Const (VarDecl
+  attributes: (AttributeList
+    attributes: [
+      (Attribute
+        at_sign: `@` (Punct (1:1..1:2)),
+        name: `id` (Attribute (1:2..1:4)),
+        params: (ArgumentList
+          brace_open: `(` (Brace (1:4..1:5)),
+          arguments: [
+            (Expr::Primary (PrimaryExpr
+              expr: (Expr::Literal `1200` (IntLiteral (1:5..1:9))),
+            )),
+          ],
+          brace_close: `)` (Brace (1:9..1:10)),
+        ),
+      ),
+    ],
+  ),
+  storage: `override` (Keyword (1:11..1:19)),
+  name: `specular_param` (Ident (1:20..1:34)),
+  ty: (TypeDecl
+    annotator: `:` (Punct (1:34..1:35)),
+    name: (IdentExpr::Leaf `f32` (Type (1:36..1:39))),
+  ),
+  assignment: (Expr::Primary (PrimaryExpr
+    expr: (Expr::Literal `2.3` (FloatLiteral (1:42..1:45))),
+  )),
+  semicolon: `;` (Punct (1:45..1:46)),
+))
+--- Tokens ---------------------------------------------------------------------
+`@` (Punct (1:1..1:2))
+`id` (Attribute (1:2..1:4))
+`(` (Brace (1:4..1:5))
+`1200` (IntLiteral (1:5..1:9))
+`)` (Brace (1:9..1:10))
+`override` (Keyword (1:11..1:19))
+`specular_param` (Ident (1:20..1:34))
+`:` (Punct (1:34..1:35))
+`f32` (Type (1:36..1:39))
+`=` (Operator (1:40..1:41))
+`2.3` (FloatLiteral (1:42..1:45))
+`;` (Punct (1:45..1:46))
+================================================================================

packages/parser/snapshots/tests/decl/override_decl-003.wgsl-ast

@@ -0,0 +1,41 @@
+================================================================================
+tests::decl::override_decl / #3
+================================================================================
+(Decl::Const (VarDecl
+  attributes: (AttributeList
+    attributes: [
+      (Attribute
+        at_sign: `@` (Punct (1:1..1:2)),
+        name: `id` (Attribute (1:2..1:4)),
+        params: (ArgumentList
+          brace_open: `(` (Brace (1:4..1:5)),
+          arguments: [
+            (Expr::Primary (PrimaryExpr
+              expr: (Expr::Literal `1300` (IntLiteral (1:5..1:9))),
+            )),
+          ],
+          brace_close: `)` (Brace (1:9..1:10)),
+        ),
+      ),
+    ],
+  ),
+  storage: `override` (Keyword (1:11..1:19)),
+  name: `gain` (Ident (1:20..1:24)),
+  ty: (TypeDecl
+    annotator: `:` (Punct (1:24..1:25)),
+    name: (IdentExpr::Leaf `f32` (Type (1:26..1:29))),
+  ),
+  semicolon: `;` (Punct (1:29..1:30)),
+))
+--- Tokens ---------------------------------------------------------------------
+`@` (Punct (1:1..1:2))
+`id` (Attribute (1:2..1:4))
+`(` (Brace (1:4..1:5))
+`1300` (IntLiteral (1:5..1:9))
+`)` (Brace (1:9..1:10))
+`override` (Keyword (1:11..1:19))
+`gain` (Ident (1:20..1:24))
+`:` (Punct (1:24..1:25))
+`f32` (Type (1:26..1:29))
+`;` (Punct (1:29..1:30))
+================================================================================

packages/parser/snapshots/tests/decl/override_decl-004.wgsl-ast

@@ -0,0 +1,24 @@
+================================================================================
+tests::decl::override_decl / #4
+================================================================================
+(Decl::Const (VarDecl
+  storage: `override` (Keyword (1:1..1:9)),
+  name: `width` (Ident (1:10..1:15)),
+  ty: (TypeDecl
+    annotator: `:` (Punct (1:15..1:16)),
+    name: (IdentExpr::Leaf `f32` (Type (1:17..1:20))),
+  ),
+  assignment: (Expr::Primary (PrimaryExpr
+    expr: (Expr::Literal `0.0` (FloatLiteral (1:23..1:26))),
+  )),
+  semicolon: `;` (Punct (1:26..1:27)),
+))
+--- Tokens ---------------------------------------------------------------------
+`override` (Keyword (1:1..1:9))
+`width` (Ident (1:10..1:15))
+`:` (Punct (1:15..1:16))
+`f32` (Type (1:17..1:20))
+`=` (Operator (1:21..1:22))
+`0.0` (FloatLiteral (1:23..1:26))
+`;` (Punct (1:26..1:27))
+================================================================================

packages/parser/snapshots/tests/decl/override_decl-005.wgsl-ast

@@ -0,0 +1,19 @@
+================================================================================
+tests::decl::override_decl / #5
+================================================================================
+(Decl::Const (VarDecl
+  storage: `override` (Keyword (1:1..1:9)),
+  name: `depth` (Ident (1:10..1:15)),
+  ty: (TypeDecl
+    annotator: `:` (Punct (1:15..1:16)),
+    name: (IdentExpr::Leaf `f32` (Type (1:17..1:20))),
+  ),
+  semicolon: `;` (Punct (1:20..1:21)),
+))
+--- Tokens ---------------------------------------------------------------------
+`override` (Keyword (1:1..1:9))
+`depth` (Ident (1:10..1:15))
+`:` (Punct (1:15..1:16))
+`f32` (Type (1:17..1:20))
+`;` (Punct (1:20..1:21))
+================================================================================

packages/parser/snapshots/tests/decl/override_decl-006.wgsl-ast

@@ -0,0 +1,26 @@
+================================================================================
+tests::decl::override_decl / #6
+================================================================================
+(Decl::Const (VarDecl
+  storage: `override` (Keyword (1:1..1:9)),
+  name: `height` (Ident (1:10..1:16)),
+  assignment: (Expr::Binary (BinaryExpr
+    lhs: (Expr::Primary (PrimaryExpr
+      expr: (Expr::Literal `2` (IntLiteral (1:19..1:20))),
+    )),
+    op: `*` (Operator (1:21..1:22)),
+    rhs: (Expr::Primary (PrimaryExpr
+      expr: (Expr::Ident (IdentExpr::Leaf `depth` (Ident (1:23..1:28)))),
+    )),
+  )),
+  semicolon: `;` (Punct (1:28..1:29)),
+))
+--- Tokens ---------------------------------------------------------------------
+`override` (Keyword (1:1..1:9))
+`height` (Ident (1:10..1:16))
+`=` (Operator (1:17..1:18))
+`2` (IntLiteral (1:19..1:20))
+`*` (Operator (1:21..1:22))
+`depth` (Ident (1:23..1:28))
+`;` (Punct (1:28..1:29))
+================================================================================

packages/parser/src/decl/mod.rs

@@ -114,7 +114,7 @@ impl Parse for Decl {
 					}
 				}
 				(Keyword, "var", _) => Ok(Decl::Var(input.parse()?)),
-				(Keyword, "let" | "const", _) => Ok(Decl::Const(input.parse()?)),
+				(Keyword, "let" | "const" | "override", _) => Ok(Decl::Const(input.parse()?)),
 				(Keyword, "alias", _) => Ok(Decl::TypeAlias(input.parse()?)),
 				(Keyword, "struct", _) => Ok(Decl::Struct(input.parse()?)),
 				(Keyword, "fn", _) => Ok(Decl::Function(input.parse()?)),
@@ -123,7 +123,8 @@ impl Parse for Decl {
 				(Directive, "#import", _) => Ok(Decl::Import(input.parse()?)),
 				(Keyword, "import", _) => Ok(Decl::Module(input.parse()?)),
 				(_, _, span) => Err(SpannedError {
-					message: "Expected `var`, `let`, `const`, `alias`, `struct`, `fn`, `enable`, or `import`"
+					message: "Expected `var`, `let`, `const`, `override`, `alias`, \
+						`struct`, `fn`, `enable`, or `import`"
 						.into(),
 					span: Some(span),
 					source: input.source(),

packages/parser/src/decl/var.rs

@@ -27,7 +27,7 @@ impl Parse for VarDecl {
 		let storage = input.consume_kind(TokenKind::Keyword)?;
 		assert!(matches!(
 			storage.as_matchable(),
-			(TokenKind::Keyword, "let" | "const" | "var", _)
+			(TokenKind::Keyword, "let" | "const" | "override" | "var", _)
 		));
 
 		let storage_qualifiers = if input.check(operator![<]) {

packages/parser/src/tests/decl.rs

@@ -24,6 +24,16 @@ fn var_decl() {
 	snapshot!(Decl(WithTokens) "const PI: f32 = 3.14159;");
 }
 
+#[snapshot_test]
+fn override_decl() {
+	snapshot!(Decl(WithTokens) "@id(0) override has_point_light: bool = true;");
+	snapshot!(Decl(WithTokens) "@id(1200) override specular_param: f32 = 2.3;");
+	snapshot!(Decl(WithTokens) "@id(1300) override gain: f32;");
+	snapshot!(Decl(WithTokens) "override width: f32 = 0.0;");
+	snapshot!(Decl(WithTokens) "override depth: f32;");
+	snapshot!(Decl(WithTokens) "override height = 2 * depth;");
+}
+
 #[snapshot_test]
 fn type_alias_decl() {
 	snapshot! {

packages/parser/src/token.rs

@@ -47,7 +47,7 @@ pub enum Token {
 	PreprocessorInsertion(Substr, Span),
 
 	#[subset_of(Ident)]
-	#[pattern = r"(const|fn|let|struct|alias|var|export)"]
+	#[pattern = r"(const|fn|let|struct|alias|var|override|export)"]
 	#[pattern = r"(function|private|read(_write)?|storage|uniform|workgroup|write)"]
 	#[pattern = r"(break|case|continu(e|ing)|default|else|fallthrough|for|if|loop|return|switch|from)"]
 	#[pattern = r"(true|false)"]