start top-level entry point tests

Author: matklad

crates/parser/src/tests.rs

@@ -86,22 +86,34 @@ fn parse(entry: TopEntryPoint, text: &str) -> (String, bool) {
  let mut buf = String::new();
  let mut errors = Vec::new();
  let mut indent = String::new();
+ let mut depth = 0;
+ let mut len = 0;
  lexed.intersperse_trivia(&output, &mut |step| match step {
  crate::StrStep::Token { kind, text } => {
+ assert!(depth > 0);
+ len += text.len();
  write!(buf, "{}", indent).unwrap();
  write!(buf, "{:?} {:?}\n", kind, text).unwrap();
  }
  crate::StrStep::Enter { kind } => {
+ assert!(depth > 0 || len == 0);
+ depth += 1;
  write!(buf, "{}", indent).unwrap();
  write!(buf, "{:?}\n", kind).unwrap();
  indent.push_str(" ");
  }
  crate::StrStep::Exit => {
+ assert!(depth > 0);
+ depth -= 1;
  indent.pop();
  indent.pop();
  }
- crate::StrStep::Error { msg, pos } => errors.push(format!("error {}: {}\n", pos, msg)),
+ crate::StrStep::Error { msg, pos } => {
+ assert!(depth > 0);
+ errors.push(format!("error {}: {}\n", pos, msg))
+ }
  });
+ assert_eq!(len, text.len());
 
  for (token, msg) in lexed.errors() {
  let pos = lexed.text_start(token);

crates/parser/src/tests/entries.rs

@@ -1,4 +1,6 @@
-use crate::{LexedStr, PrefixEntryPoint, Step};
+use expect_test::expect;
+
+use crate::{LexedStr, PrefixEntryPoint, Step, TopEntryPoint};
 
 #[test]
 fn vis() {
@@ -83,6 +85,7 @@ fn meta_item() {
  check_prefix(PrefixEntryPoint::MetaItem, "path::attr = 2 * 2!", "path::attr = 2 * 2");
 }
 
+#[track_caller]
 fn check_prefix(entry: PrefixEntryPoint, input: &str, prefix: &str) {
  let lexed = LexedStr::new(input);
  let input = lexed.to_input();
@@ -108,3 +111,56 @@ fn check_prefix(entry: PrefixEntryPoint, input: &str, prefix: &str) {
  let buf = &lexed.as_str()[..lexed.text_start(i)];
  assert_eq!(buf, prefix);
 }
+
+#[test]
+fn source_file() {
+ check_top(
+ TopEntryPoint::SourceFile,
+ "",
+ expect![[r#"
+ SOURCE_FILE
+ "#]],
+ );
+
+ check_top(
+ TopEntryPoint::SourceFile,
+ "struct S;",
+ expect![[r#"
+ SOURCE_FILE
+ STRUCT
+ STRUCT_KW "struct"
+ WHITESPACE " "
+ NAME
+ IDENT "S"
+ SEMICOLON ";"
+ "#]],
+ );
+
+ check_top(
+ TopEntryPoint::SourceFile,
+ "@error@",
+ expect![[r#"
+ SOURCE_FILE
+ ERROR
+ AT "@"
+ MACRO_CALL
+ PATH
+ PATH_SEGMENT
+ NAME_REF
+ IDENT "error"
+ ERROR
+ AT "@"
+ error 0: expected an item
+ error 6: expected BANG
+ error 6: expected `{`, `[`, `(`
+ error 6: expected SEMICOLON
+ error 6: expected an item
+ "#]],
+ );
+}
+
+#[track_caller]
+fn check_top(entry: TopEntryPoint, input: &str, expect: expect_test::Expect) {
+ let (parsed, _errors) = super::parse(entry, input);
+ expect.assert_eq(&parsed)
+}