Add type-checking to classes/fields/constructors.

dmc-lib/src/ast/class.rs

@@ -5,6 +5,7 @@ use crate::diagnostic::Diagnostic;
 use crate::source_range::SourceRange;
 use crate::symbol::class_symbol::ClassSymbol;
 use crate::symbol_table::{SymbolInsertError, SymbolTable};
+use std::collections::HashSet;
 use std::rc::Rc;
 
 pub struct Class {
@@ -138,10 +139,6 @@ impl Class {
     }
 
     pub fn type_check(&mut self, symbol_table: &SymbolTable) -> Result<(), Vec<Diagnostic>> {
-        // We need to determine if fields are initialized or not (the latter is an error).
-        // First phase: check all fields, then check constructor, leaving pending those things that
-        // are fields <- initialized by constructor. Then circle back to fields and check all are
-        // initialized
         let mut diagnostics: Vec<Diagnostic> = vec![];
 
         self.fields
@@ -151,7 +148,58 @@ impl Class {
             .flatten()
             .for_each(|diagnostic| diagnostics.push(diagnostic));
 
-        // todo check constructor and functions and re-check fields
+        if let Some(constructor) = &mut self.constructor {
+            match constructor.type_check(symbol_table) {
+                Ok(_) => {}
+                Err(mut constructor_diagnostics) => {
+                    diagnostics.append(&mut constructor_diagnostics);
+                }
+            }
+        }
+
+        self.functions
+            .iter_mut()
+            .map(|function| function.type_check(symbol_table))
+            .filter_map(Result::err)
+            .flatten()
+            .for_each(|diagnostic| diagnostics.push(diagnostic));
+
+        // We need to determine if fields are initialized or not (the latter is an error).
+        // First phase: check all fields, then check constructor, leaving pending those things that
+        // are fields <- initialized by constructor. Then circle back to fields and check all are
+        // initialized
+        let mut initialized_field_names: HashSet<&str> = HashSet::new();
+
+        for field in &self.fields {
+            if field.initializer().is_some() {
+                initialized_field_names.insert(field.declared_name());
+            }
+        }
+
+        // check constructor
+        if let Some(constructor) = &self.constructor {
+            for statement in constructor.statements() {
+                match statement {
+                    _ => {
+                        // no-op for now, because we don't yet have assign statements
+                    }
+                }
+            }
+        }
+
+        // check that all fields are present in the hash set
+        for field in &self.fields {
+            if !initialized_field_names.contains(field.declared_name()) {
+                diagnostics.push(
+                    Diagnostic::new(
+                        &format!("Field {} is not initialized.", field.declared_name()),
+                        field.declared_name_source_range().start(),
+                        field.declared_name_source_range().end(),
+                    )
+                    .with_reporter(file!(), line!()),
+                )
+            }
+        }
 
         if diagnostics.is_empty() {
             Ok(())
@@ -167,11 +215,11 @@ mod tests {
     use crate::parser::parse_compilation_unit;
 
     #[test]
-    fn name_analysis_no_diagnostics() {
+    fn complete_example_no_diagnostics() {
         let parse_result = parse_compilation_unit(
             "
             class Foo
-                mut bar: Int
+                mut bar: Int = 42
 
                 ctor(_bar: Int)
                 end
@@ -210,5 +258,12 @@ mod tests {
                 panic!("{:?}", diagnostics);
             }
         }
+
+        match compilation_unit.type_check(&symbol_table) {
+            Ok(_) => {}
+            Err(diagnostics) => {
+                panic!("{:?}", diagnostics);
+            }
+        }
     }
 }

dmc-lib/src/ast/constructor.rs

@@ -30,6 +30,10 @@ impl Constructor {
         }
     }
 
+    pub fn statements(&self) -> &[Statement] {
+        &self.statements
+    }
+
     pub fn gather_declared_names(
         &mut self,
         symbol_table: &mut SymbolTable,
@@ -124,4 +128,32 @@ impl Constructor {
             Err(statements_diagnostics)
         }
     }
+
+    pub fn type_check(&mut self, symbol_table: &SymbolTable) -> Result<(), Vec<Diagnostic>> {
+        let parameters_diagnostics: Vec<Diagnostic> = self
+            .parameters
+            .iter_mut()
+            .map(|param| param.type_check(symbol_table))
+            .filter_map(Result::err)
+            .flatten()
+            .collect();
+
+        if !parameters_diagnostics.is_empty() {
+            return Err(parameters_diagnostics);
+        }
+
+        let statements_diagnostics: Vec<Diagnostic> = self
+            .statements
+            .iter_mut()
+            .map(|statement| statement.type_check(symbol_table, None))
+            .filter_map(Result::err)
+            .flatten()
+            .collect();
+
+        if statements_diagnostics.is_empty() {
+            Ok(())
+        } else {
+            Err(statements_diagnostics)
+        }
+    }
 }

dmc-lib/src/ast/expression_statement.rs

@@ -3,10 +3,8 @@ use crate::ast::ir_builder::IrBuilder;
 use crate::diagnostic::Diagnostic;
 use crate::ir::ir_return::IrReturn;
 use crate::ir::ir_statement::IrStatement;
-use crate::symbol::function_symbol::FunctionSymbol;
 use crate::symbol_table::SymbolTable;
-use std::cell::RefCell;
-use std::rc::Rc;
+use crate::type_info::TypeInfo;
 
 pub struct ExpressionStatement {
     expression: Box<Expression>,
@@ -37,15 +35,13 @@ impl ExpressionStatement {
     pub fn type_check(
         &mut self,
         symbol_table: &SymbolTable,
-        is_last: bool,
-        function_symbol: &Rc<RefCell<FunctionSymbol>>,
+        must_return_type_info: Option<&TypeInfo>,
     ) -> Result<(), Vec<Diagnostic>> {
         self.expression.type_check(symbol_table)?;
 
-        if is_last {
+        if must_return_type_info.is_some() {
             let expression_type = self.expression.type_info();
-            let borrowed_symbol = function_symbol.borrow();
-            let return_type = borrowed_symbol.return_type_info();
+            let return_type = must_return_type_info.unwrap();
             if !return_type.is_assignable_from(expression_type) {
                 return Err(vec![Diagnostic::new(
                     &format!(

dmc-lib/src/ast/field.rs

@@ -37,6 +37,18 @@ impl Field {
         }
     }
 
+    pub fn declared_name(&self) -> &str {
+        &self.declared_name
+    }
+
+    pub fn declared_name_source_range(&self) -> &SourceRange {
+        &self.declared_name_source_range
+    }
+
+    pub fn initializer(&self) -> Option<&Expression> {
+        self.initializer.as_ref().map(Box::as_ref)
+    }
+
     pub fn gather_declared_names(
         &mut self,
         symbol_table: &mut SymbolTable,

dmc-lib/src/ast/function.rs

@@ -208,6 +208,7 @@ impl Function {
         );
 
         let function_symbol = self.function_symbol.as_ref().unwrap();
+        let return_type_info = function_symbol.borrow().return_type_info().clone();
         let statements_len = self.statements.len();
 
         // statements
@@ -218,7 +219,11 @@ impl Function {
                 .enumerate()
                 .map(|(i, statement)| {
                     let is_last = i == statements_len - 1;
-                    statement.type_check(symbol_table, is_last, function_symbol)
+                    if is_last {
+                        statement.type_check(symbol_table, Some(&return_type_info))
+                    } else {
+                        statement.type_check(symbol_table, None)
+                    }
                 })
                 .filter_map(Result::err)
                 .flatten()

dmc-lib/src/ast/parameter.rs

@@ -36,7 +36,7 @@ impl Parameter {
         let insert_result = symbol_table.insert_parameter_symbol(ParameterSymbol::new(
             &self.declared_name,
             self.declared_name_source_range.clone(),
-            TypeInfo::from_declared_name(self.type_use.declared_name()),
+            TypeInfo::from_declared_name(self.type_use.declared_name()), // todo: this will blow up if type is a Class
         ));
         match insert_result {
             Ok(parameter_symbol) => {

dmc-lib/src/ast/statement.rs

@@ -2,10 +2,8 @@ use crate::ast::expression_statement::ExpressionStatement;
 use crate::ast::ir_builder::IrBuilder;
 use crate::ast::let_statement::LetStatement;
 use crate::diagnostic::Diagnostic;
-use crate::symbol::function_symbol::FunctionSymbol;
 use crate::symbol_table::SymbolTable;
-use std::cell::RefCell;
-use std::rc::Rc;
+use crate::type_info::TypeInfo;
 
 pub enum Statement {
     Let(LetStatement),
@@ -37,13 +35,12 @@ impl Statement {
     pub fn type_check(
         &mut self,
         symbol_table: &SymbolTable,
-        is_last: bool,
-        function_symbol: &Rc<RefCell<FunctionSymbol>>,
+        must_return_type_info: Option<&TypeInfo>,
     ) -> Result<(), Vec<Diagnostic>> {
         match self {
             Statement::Let(let_statement) => let_statement.type_check(symbol_table),
             Statement::Expression(expression_statement) => {
-                expression_statement.type_check(symbol_table, is_last, function_symbol)
+                expression_statement.type_check(symbol_table, must_return_type_info)
             }
         }
     }

dmc-lib/src/ast/type_use.rs

@@ -56,7 +56,7 @@ impl TypeUse {
         }
     }
 
-    pub fn type_check(&mut self, symbol_table: &SymbolTable) -> Result<(), Vec<Diagnostic>> {
+    pub fn type_check(&mut self, _symbol_table: &SymbolTable) -> Result<(), Vec<Diagnostic>> {
         Ok(()) // no-op, for now
     }