Add parser/failure tests from spec

1 files changed, 82 insertions, 81 deletions

diff --git a/dhall/src/parser.rs b/dhall/src/parser.rs
index 0acfe39..9259dfd 100644
--- a/dhall/src/parser.rs
+++ b/dhall/src/parser.rs
@@ -7,7 +7,7 @@ use crate::core::{bx, Expr, V};
 
 pub type ParseError<'i> = lalrpop_util::ParseError<usize, Tok<'i>, LexicalError>;
 
-pub fn parse_expr(s: &str) -> Result<BoxExpr, ParseError>  {
+pub fn parse_expr_lalrpop(s: &str) -> Result<BoxExpr, ParseError>  {
     grammar::ExprParser::new().parse(Lexer::new(s))
 }
 
@@ -48,80 +48,81 @@ fn debug_pair(pair: Pair<Rule>) {
     aux(0, "".into(), pair)
 }
 
-pub fn parse_expr_pest(s: &str) -> Result<BoxExpr, Error<Rule>>  {
-    let parsed_expr = DhallParser::parse(Rule::final_expression, s)?.next().unwrap();
-    debug_pair(parsed_expr.clone());
-    // println!("{}", parsed_expr.clone());
-
-    fn parse_binop<'a, F>(pair: Pair<'a, Rule>, mut f: F) -> BoxExpr<'a>
-    where F: FnMut(BoxExpr<'a>, BoxExpr<'a>) -> ParsedExpr<'a> {
-        let mut inner = pair.into_inner().map(parse_expression);
-        let first_expr = inner.next().unwrap();
-        inner.fold(first_expr, |acc, e| bx(f(acc, e)))
-    }
+fn parse_binop<'a, F>(pair: Pair<'a, Rule>, mut f: F) -> BoxExpr<'a>
+where F: FnMut(BoxExpr<'a>, BoxExpr<'a>) -> ParsedExpr<'a> {
+    let mut inner = pair.into_inner().map(parse_expression);
+    let first_expr = inner.next().unwrap();
+    inner.fold(first_expr, |acc, e| bx(f(acc, e)))
+}
 
-    fn skip_expr(pair: Pair<Rule>) -> BoxExpr {
-        let mut inner = pair.into_inner().map(parse_expression);
-        inner.next().unwrap()
-    }
+fn skip_expr(pair: Pair<Rule>) -> BoxExpr {
+    let mut inner = pair.into_inner().map(parse_expression);
+    inner.next().unwrap()
+}
 
-    fn parse_str(pair: Pair<Rule>) -> &str {
-        pair.as_str().trim()
-    }
+fn parse_str(pair: Pair<Rule>) -> &str {
+    pair.as_str().trim()
+}
 
-    fn parse_natural(pair: Pair<Rule>) -> Result<usize, std::num::ParseIntError> {
-        parse_str(pair).parse()
-    }
+fn parse_natural(pair: Pair<Rule>) -> Result<usize, std::num::ParseIntError> {
+    parse_str(pair).parse()
+}
 
-    fn parse_expression(pair: Pair<Rule>) -> BoxExpr {
-        match pair.as_rule() {
-            Rule::natural_literal_raw => bx(Expr::NaturalLit(parse_natural(pair).unwrap())),
-
-            Rule::annotated_expression => { parse_binop(pair, Expr::Annot) }
-            Rule::import_alt_expression => { skip_expr(pair) }
-            Rule::or_expression => { parse_binop(pair, Expr::BoolOr) }
-            Rule::plus_expression => { parse_binop(pair, Expr::NaturalPlus) }
-            Rule::text_append_expression => { parse_binop(pair, Expr::TextAppend) }
-            Rule::list_append_expression => { skip_expr(pair) }
-            Rule::and_expression => { parse_binop(pair, Expr::BoolAnd) }
-            Rule::combine_expression => { skip_expr(pair) }
-            Rule::prefer_expression => { skip_expr(pair) }
-            Rule::combine_types_expression => { skip_expr(pair) }
-            Rule::times_expression => { parse_binop(pair, Expr::NaturalTimes) }
-            Rule::equal_expression => { parse_binop(pair, Expr::BoolEQ) }
-            Rule::not_equal_expression => { parse_binop(pair, Expr::BoolNE) }
-            Rule::application_expression => { parse_binop(pair, Expr::App) }
-
-            Rule::selector_expression_raw => {
-                let mut inner = pair.into_inner();
-                let first_expr = parse_expression(inner.next().unwrap());
-                inner.fold(first_expr, |acc, e| bx(Expr::Field(acc, e.as_str())))
-            }
+fn parse_expression(pair: Pair<Rule>) -> BoxExpr {
+    match pair.as_rule() {
+        Rule::natural_literal_raw => bx(Expr::NaturalLit(parse_natural(pair).unwrap())),
+
+        Rule::annotated_expression => { parse_binop(pair, Expr::Annot) }
+        Rule::import_alt_expression => { skip_expr(pair) }
+        Rule::or_expression => { parse_binop(pair, Expr::BoolOr) }
+        Rule::plus_expression => { parse_binop(pair, Expr::NaturalPlus) }
+        Rule::text_append_expression => { parse_binop(pair, Expr::TextAppend) }
+        Rule::list_append_expression => { skip_expr(pair) }
+        Rule::and_expression => { parse_binop(pair, Expr::BoolAnd) }
+        Rule::combine_expression => { skip_expr(pair) }
+        Rule::prefer_expression => { skip_expr(pair) }
+        Rule::combine_types_expression => { skip_expr(pair) }
+        Rule::times_expression => { parse_binop(pair, Expr::NaturalTimes) }
+        Rule::equal_expression => { parse_binop(pair, Expr::BoolEQ) }
+        Rule::not_equal_expression => { parse_binop(pair, Expr::BoolNE) }
+        Rule::application_expression => { parse_binop(pair, Expr::App) }
+
+        Rule::selector_expression_raw => {
+            let mut inner = pair.into_inner();
+            let first_expr = parse_expression(inner.next().unwrap());
+            inner.fold(first_expr, |acc, e| bx(Expr::Field(acc, e.as_str())))
+        }
 
-            Rule::identifier_raw => {
-                let mut inner = pair.into_inner();
-                let name = parse_str(inner.next().unwrap());
-                let idx = inner.next().map(parse_natural).unwrap_or(Ok(0)).unwrap();
-                bx(Expr::Var(V(name, idx)))
-            }
+        Rule::identifier_raw => {
+            let mut inner = pair.into_inner();
+            let name = parse_str(inner.next().unwrap());
+            let idx = inner.next().map(parse_natural).unwrap_or(Ok(0)).unwrap();
+            bx(Expr::Var(V(name, idx)))
+        }
 
 
-            // Rule::record_type_or_literal => {
-            //     let mut inner = pair.into_inner();
-            //     let first_expr = parse_expression(inner.next().unwrap());
-            //     inner.fold(first_expr, |acc, e| bx(Expr::Field(acc, e.as_str())))
-            // }
+        // Rule::record_type_or_literal => {
+        //     let mut inner = pair.into_inner();
+        //     let first_expr = parse_expression(inner.next().unwrap());
+        //     inner.fold(first_expr, |acc, e| bx(Expr::Field(acc, e.as_str())))
+        // }
 
-            // r => panic!("{:?}", r),
-            // _ => bx(Expr::BoolLit(false)),
+        // r => panic!("{:?}", r),
+        // _ => bx(Expr::BoolLit(false)),
 
-            _ => {
-                let rulename = format!("{:?}", pair.as_rule());
-                let mut inner = pair.into_inner().map(parse_expression).map(|x| *x);
-                bx(Expr::FailedParse(rulename, inner.collect()))
-            }
+        _ => {
+            let rulename = format!("{:?}", pair.as_rule());
+            let mut inner = pair.into_inner().map(parse_expression).map(|x| *x);
+            bx(Expr::FailedParse(rulename, inner.collect()))
         }
     }
+}
+
+pub fn parse_expr_pest(s: &str) -> Result<BoxExpr, Error<Rule>>  {
+    let parsed_expr = DhallParser::parse(Rule::final_expression, s)?.next().unwrap();
+    debug_pair(parsed_expr.clone());
+    // println!("{}", parsed_expr.clone());
+
 
     Ok(parse_expression(parsed_expr))
 }
@@ -133,7 +134,7 @@ fn test_parse() {
     // let expr = r#"{ x = "foo", y = 4 }.x"#;
     // let expr = r#"(1 + 2) * 3"#;
     let expr = r#"if True then 1 + 3 * 5 else 2"#;
-    println!("{:?}", parse_expr(expr));
+    println!("{:?}", parse_expr_lalrpop(expr));
     match parse_expr_pest(expr) {
         Err(e) => {
             println!("{:?}", e);
@@ -144,27 +145,27 @@ fn test_parse() {
     // assert_eq!(parse_expr_pest(expr).unwrap(), parse_expr(expr).unwrap());
     assert!(false);
 
-    println!("test {:?}", parse_expr("3 + 5 * 10"));
-    assert!(parse_expr("22").is_ok());
-    assert!(parse_expr("(22)").is_ok());
-    assert_eq!(parse_expr("3 + 5 * 10").ok(),
+    println!("test {:?}", parse_expr_lalrpop("3 + 5 * 10"));
+    assert!(parse_expr_lalrpop("22").is_ok());
+    assert!(parse_expr_lalrpop("(22)").is_ok());
+    assert_eq!(parse_expr_lalrpop("3 + 5 * 10").ok(),
                Some(Box::new(NaturalPlus(Box::new(NaturalLit(3)),
                                 Box::new(NaturalTimes(Box::new(NaturalLit(5)),
                                                       Box::new(NaturalLit(10))))))));
     // The original parser is apparently right-associative
-    assert_eq!(parse_expr("2 * 3 * 4").ok(),
+    assert_eq!(parse_expr_lalrpop("2 * 3 * 4").ok(),
                Some(Box::new(NaturalTimes(Box::new(NaturalLit(2)),
                                  Box::new(NaturalTimes(Box::new(NaturalLit(3)),
                                                        Box::new(NaturalLit(4))))))));
-    assert!(parse_expr("((((22))))").is_ok());
-    assert!(parse_expr("((22)").is_err());
-    println!("{:?}", parse_expr("\\(b : Bool) -> b == False"));
-    assert!(parse_expr("\\(b : Bool) -> b == False").is_ok());
-    println!("{:?}", parse_expr("foo.bar"));
-    assert!(parse_expr("foo.bar").is_ok());
-    assert!(parse_expr("[] : List Bool").is_ok());
-
-    // println!("{:?}", parse_expr("< Left = True | Right : Natural >"));
-    // println!("{:?}", parse_expr(r#""bl${42}ah""#));
-    // assert!(parse_expr("< Left = True | Right : Natural >").is_ok());
+    assert!(parse_expr_lalrpop("((((22))))").is_ok());
+    assert!(parse_expr_lalrpop("((22)").is_err());
+    println!("{:?}", parse_expr_lalrpop("\\(b : Bool) -> b == False"));
+    assert!(parse_expr_lalrpop("\\(b : Bool) -> b == False").is_ok());
+    println!("{:?}", parse_expr_lalrpop("foo.bar"));
+    assert!(parse_expr_lalrpop("foo.bar").is_ok());
+    assert!(parse_expr_lalrpop("[] : List Bool").is_ok());
+
+    // println!("{:?}", parse_expr_lalrpop("< Left = True | Right : Natural >"));
+    // println!("{:?}", parse_expr_lalrpop(r#""bl${42}ah""#));
+    // assert!(parse_expr_lalrpop("< Left = True | Right : Natural >").is_ok());
 }