rebel-parse: implement validation for statements

2 files changed, 42 insertions, 3 deletions

diff --git a/crates/rebel-parse/src/ast.rs b/crates/rebel-parse/src/ast.rs
index 1dcbdd9..e3b93ba 100644
--- a/crates/rebel-parse/src/ast.rs
+++ b/crates/rebel-parse/src/ast.rs
@@ -18,7 +18,34 @@ pub enum RecipeStmt<'a> {
 	},
 }
 
-pub type Body<'a> = Vec<BodyStmt<'a>>;
+impl<'a> RecipeStmt<'a> {
+	pub fn validate(&self) -> Result<(), ValidationError> {
+		match self {
+			RecipeStmt::BodyStmt(stmt) => stmt.validate(),
+			RecipeStmt::Fetch { name: _, body } => body.validate(),
+			RecipeStmt::Task {
+				name: _,
+				params: _,
+				body,
+			} => {
+				// TODO: Validate params?
+				body.validate()
+			}
+		}
+	}
+}
+
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub struct Body<'a>(pub Vec<BodyStmt<'a>>);
+
+impl<'a> Body<'a> {
+	pub fn validate(&self) -> Result<(), ValidationError> {
+		for stmt in &self.0 {
+			stmt.validate()?;
+		}
+		Ok(())
+	}
+}
 
 #[derive(Debug, Clone, PartialEq, Eq)]
 pub enum BodyStmt<'a> {
@@ -40,6 +67,18 @@ impl<'a> BodyStmt<'a> {
 			None => BodyStmt::Assign { dest, expr },
 		}
 	}
+
+	pub fn validate(&self) -> Result<(), ValidationError> {
+		match self {
+			BodyStmt::Assign { dest, expr } => {
+				// TODO: Extend destination validation
+				dest.expr.validate()?;
+				expr.validate()
+			}
+			BodyStmt::Expr { expr } => expr.validate(),
+			BodyStmt::Empty => Ok(()),
+		}
+	}
 }
 
 #[derive(Debug, Clone, PartialEq, Eq)]
diff --git a/crates/rebel-parse/src/grammar/recipe.rs b/crates/rebel-parse/src/grammar/recipe.rs
index 71c2733..393b12c 100644
--- a/crates/rebel-parse/src/grammar/recipe.rs
+++ b/crates/rebel-parse/src/grammar/recipe.rs
@@ -13,7 +13,7 @@ peg::parser! {
 
 		pub rule recipe_stmt() -> ast::RecipeStmt<'a>
 			= keyword_fetch() name:ident() p('{') body:body() p('}') {
-				ast::RecipeStmt::Fetch { name, body: Vec::new() }
+				ast::RecipeStmt::Fetch { name, body: ast::Body(Vec::new()) }
 			}
 			/ keyword_task() name:ident() p('(') params:func_params() p(')')
 			  p('{') body:body() p('}') {
@@ -24,7 +24,7 @@ peg::parser! {
 			}
 
 		pub rule body() -> ast::Body<'a>
-			= body:body_stmt() ++ p(';') { body }
+			= body:body_stmt() ++ p(';') { ast::Body(body) }
 
 		pub rule body_stmt() -> ast::BodyStmt<'a>
 			= dest:typed_expr() op:assign_op() expr:expr() {