Merge #3536

3536: Add get and set for `Env` r=matklad a=edwin0cheng

This PR add three things :

1. Add `get` and `set` in `Env`.
2. Implement fixture meta for `with_single_file`. 
3. Add `env` meta in fixture.

Co-authored-by: Edwin Cheng <[email protected]>

1 files changed, 13 insertions, 0 deletions

diff --git a/crates/test_utils/src/lib.rs b/crates/test_utils/src/lib.rs
index 69deddcb5..a0d8f4d37 100644
--- a/crates/test_utils/src/lib.rs
+++ b/crates/test_utils/src/lib.rs
@@ -202,6 +202,19 @@ pub fn parse_fixture(fixture: &str) -> Vec<FixtureEntry> {
     res
 }
 
+/// Same as `parse_fixture`, except it allow empty fixture
+pub fn parse_single_fixture(fixture: &str) -> Option<FixtureEntry> {
+    if !fixture.lines().any(|it| it.trim_start().starts_with("//-")) {
+        return None;
+    }
+
+    let fixtures = parse_fixture(fixture);
+    if fixtures.len() > 1 {
+        panic!("too many fixtures");
+    }
+    fixtures.into_iter().nth(0)
+}
+
 // Comparison functionality borrowed from cargo:
 
 /// Compare a line with an expected pattern.