Feat/else if statements

phpast/samples/if.php

@@ -2,6 +2,10 @@
 
 if($foo) {
  return $foo;
+} elseif($foo) {
+ return $foo;
+} elseif($foo) {
+ return $foo;
 } else {
  return $foo;
 }

trunk_parser/src/ast.rs

@@ -176,6 +176,7 @@ pub enum Statement {
  If {
  condition: Expression,
  then: Block,
+ else_ifs: Vec<ElseIf>,
  r#else: Option<Block>
  },
  Return {
@@ -271,4 +272,10 @@ impl From<TokenKind> for InfixOp {
  _ => unreachable!()
  }
  }
+}
+
+#[derive(Debug, Clone, PartialEq, Serialize)]
+pub struct ElseIf {
+ pub condition: Expression,
+ pub body: Block,
 }

trunk_parser/src/parser/mod.rs

@@ -1,6 +1,6 @@
 use std::{vec::IntoIter, fmt::{Display}};
 use trunk_lexer::{Token, TokenKind, Span};
-use crate::{Program, Statement, Block, Expression, ast::{ArrayItem, Use, MethodFlag, ClassFlag}, Identifier, Type, Param};
+use crate::{Program, Statement, Block, Expression, ast::{ArrayItem, Use, MethodFlag, ClassFlag, ElseIf}, Identifier, Type, Param};
 
 type ParseResult<T> = Result<T, ParseError>;
 
@@ -354,8 +354,34 @@ impl Parser {
  expect!(self, TokenKind::RightBrace, "expected }");
  }
 
+ let mut else_ifs: Vec<ElseIf> = Vec::new();
+ loop {
+ if self.current.kind == TokenKind::ElseIf {
+ self.next();
+
+ expect!(self, TokenKind::LeftParen, "expected (");
+
+ let condition = self.expression(0)?;
+
+ expect!(self, TokenKind::RightParen, "expected )");
+
+ expect!(self, TokenKind::LeftBrace, "expected {");
+
+ let mut body = Block::new();
+ while ! self.is_eof() && self.current.kind != TokenKind::RightBrace {
+ body.push(self.statement()?);
+ }
+
+ expect!(self, TokenKind::RightBrace, "expected }");
+
+ else_ifs.push(ElseIf { condition, body });
+ } else {
+ break;
+ }
+ }
+
  if self.current.kind != TokenKind::Else {
- return Ok(Statement::If { condition, then, r#else: None });
+ return Ok(Statement::If { condition, then, else_ifs, r#else: None });
  }
 
  expect!(self, TokenKind::Else, "expected else");
@@ -369,7 +395,7 @@ impl Parser {
 
  expect!(self, TokenKind::RightBrace, "expected }");
 
- Statement::If { condition, then, r#else: Some(r#else) }
+ Statement::If { condition, then, else_ifs, r#else: Some(r#else) }
  },
  TokenKind::Class => self.class()?,
  TokenKind::Echo => {
@@ -1005,7 +1031,7 @@ impl Display for ParseError {
 #[cfg(test)]
 mod tests {
  use trunk_lexer::Lexer;
- use crate::{Statement, Param, Expression, ast::{InfixOp}, Type, Identifier};
+ use crate::{Statement, Param, Expression, ast::{InfixOp, ElseIf}, Type, Identifier};
  use super::Parser;
 
  macro_rules! function {
@@ -1209,6 +1235,7 @@ mod tests {
  then: vec![
  Statement::Return { value: Some(Expression::Variable("n".into())) }
  ],
+ else_ifs: vec![],
  r#else: None
  },
  Statement::Return {
@@ -1248,6 +1275,7 @@ mod tests {
  then: vec![
  Statement::Return { value: Some(Expression::Variable("foo".into())) }
  ],
+ else_ifs: vec![],
  r#else: None
  },
  ]);
@@ -1261,6 +1289,30 @@ mod tests {
  then: vec![
  Statement::Return { value: Some(Expression::Variable("foo".into())) }
  ],
+ else_ifs: vec![],
+ r#else: Some(vec![
+ Statement::Return { value: Some(Expression::Variable("foo".into())) }
+ ])
+ },
+ ]);
+ }
+
+ #[test]
+ fn if_elseif_else_statement() {
+ assert_ast("<?php if($foo) { return $foo; } elseif($foo) { return $foo; } else { return $foo; }", &[
+ Statement::If {
+ condition: Expression::Variable("foo".into()),
+ then: vec![
+ Statement::Return { value: Some(Expression::Variable("foo".into())) }
+ ],
+ else_ifs: vec![
+ ElseIf {
+ condition: Expression::Variable("foo".into()),
+ body: vec![
+ Statement::Return { value: Some(Expression::Variable("foo".into())) }
+ ]
+ }
+ ],
  r#else: Some(vec![
  Statement::Return { value: Some(Expression::Variable("foo".into())) }
  ])