Complicate

Fixing test fallout unfortunately requires more work, we need to do
it, but let's merge something at least!

crates/ra_db/src/fixture.rs

@@ -74,9 +74,8 @@ pub const WORKSPACE: SourceRootId = SourceRootId(0);
 pub trait WithFixture: Default + SourceDatabaseExt + 'static {
     fn with_single_file(text: &str) -> (Self, FileId) {
         let mut db = Self::default();
-        let (_, files) = with_files(&mut db, text);
+        let file_id = with_single_file(&mut db, text);
-        assert!(files.len() == 1);
+        (db, file_id)
-        (db, files[0])
     }
 
     fn with_files(ra_fixture: &str) -> Self {
@@ -103,6 +102,52 @@ pub trait WithFixture: Default + SourceDatabaseExt + 'static {
 
 impl<DB: SourceDatabaseExt + Default + 'static> WithFixture for DB {}
 
+fn with_single_file(db: &mut dyn SourceDatabaseExt, ra_fixture: &str) -> FileId {
+    let file_id = FileId(0);
+    let mut file_set = vfs::file_set::FileSet::default();
+    file_set.insert(file_id, vfs::VfsPath::new_virtual_path("/main.rs".to_string()));
+
+    let source_root = SourceRoot::new_local(file_set);
+
+    let crate_graph = if let Some(meta) = ra_fixture.lines().find(|it| it.contains("//-")) {
+        let entry = Fixture::parse_single(meta.trim());
+        let meta = match ParsedMeta::from(&entry) {
+            ParsedMeta::File(it) => it,
+        };
+
+        let mut crate_graph = CrateGraph::default();
+        crate_graph.add_crate_root(
+            file_id,
+            meta.edition,
+            meta.krate.map(|name| {
+                CrateName::new(&name).expect("Fixture crate name should not contain dashes")
+            }),
+            meta.cfg,
+            meta.env,
+            Default::default(),
+        );
+        crate_graph
+    } else {
+        let mut crate_graph = CrateGraph::default();
+        crate_graph.add_crate_root(
+            file_id,
+            Edition::Edition2018,
+            None,
+            CfgOptions::default(),
+            Env::default(),
+            Default::default(),
+        );
+        crate_graph
+    };
+
+    db.set_file_text(file_id, Arc::new(ra_fixture.to_string()));
+    db.set_file_source_root(file_id, WORKSPACE);
+    db.set_source_root(WORKSPACE, Arc::new(source_root));
+    db.set_crate_graph(Arc::new(crate_graph));
+
+    file_id
+}
+
 fn with_files(
     db: &mut dyn SourceDatabaseExt,
     fixture: &str,

crates/test_utils/src/fixture.rs

@@ -55,8 +55,7 @@ The offending line: {:?}"#,
         let mut res: Vec<Fixture> = Vec::new();
         for line in lines.by_ref() {
             if line.starts_with("//-") {
-                let meta = line["//-".len()..].trim().to_string();
+                let meta = Fixture::parse_single(line);
-                let meta = Fixture::parse_single(&meta);
                 res.push(meta)
             } else if let Some(entry) = res.last_mut() {
                 entry.text.push_str(line);
@@ -67,7 +66,9 @@ The offending line: {:?}"#,
     }
 
     //- /lib.rs crate:foo deps:bar,baz cfg:foo=a,bar=b env:OUTDIR=path/to,OTHER=foo
-    fn parse_single(meta: &str) -> Fixture {
+    pub fn parse_single(meta: &str) -> Fixture {
+        assert!(meta.starts_with("//-"));
+        let meta = meta["//-".len()..].trim();
         let components = meta.split_ascii_whitespace().collect::<Vec<_>>();
 
         let path = components[0].to_string();