1 files changed, 176 insertions, 0 deletions

diff --git a/crates/ide/src/mock_analysis.rs b/crates/ide/src/mock_analysis.rs
new file mode 100644
index 000000000..235796dbc
--- /dev/null
+++ b/crates/ide/src/mock_analysis.rs
@@ -0,0 +1,176 @@
+//! FIXME: write short doc here
+use std::sync::Arc;
+
+use base_db::{CrateName, FileSet, SourceRoot, VfsPath};
+use cfg::CfgOptions;
+use test_utils::{
+    extract_annotations, extract_range_or_offset, Fixture, RangeOrOffset, CURSOR_MARKER,
+};
+
+use crate::{
+    Analysis, AnalysisChange, AnalysisHost, CrateGraph, Edition, FileId, FilePosition, FileRange,
+};
+
+/// Mock analysis is used in test to bootstrap an AnalysisHost/Analysis
+/// from a set of in-memory files.
+#[derive(Debug, Default)]
+pub struct MockAnalysis {
+    files: Vec<Fixture>,
+}
+
+impl MockAnalysis {
+    /// Creates `MockAnalysis` using a fixture data in the following format:
+    ///
+    /// ```not_rust
+    /// //- /main.rs
+    /// mod foo;
+    /// fn main() {}
+    ///
+    /// //- /foo.rs
+    /// struct Baz;
+    /// ```
+    pub fn with_files(ra_fixture: &str) -> MockAnalysis {
+        let (res, pos) = MockAnalysis::with_fixture(ra_fixture);
+        assert!(pos.is_none());
+        res
+    }
+
+    /// Same as `with_files`, but requires that a single file contains a `<|>` marker,
+    /// whose position is also returned.
+    pub fn with_files_and_position(fixture: &str) -> (MockAnalysis, FilePosition) {
+        let (res, position) = MockAnalysis::with_fixture(fixture);
+        let (file_id, range_or_offset) = position.expect("expected a marker (<|>)");
+        let offset = match range_or_offset {
+            RangeOrOffset::Range(_) => panic!(),
+            RangeOrOffset::Offset(it) => it,
+        };
+        (res, FilePosition { file_id, offset })
+    }
+
+    fn with_fixture(fixture: &str) -> (MockAnalysis, Option<(FileId, RangeOrOffset)>) {
+        let mut position = None;
+        let mut res = MockAnalysis::default();
+        for mut entry in Fixture::parse(fixture) {
+            if entry.text.contains(CURSOR_MARKER) {
+                assert!(position.is_none(), "only one marker (<|>) per fixture is allowed");
+                let (range_or_offset, text) = extract_range_or_offset(&entry.text);
+                entry.text = text;
+                let file_id = res.add_file_fixture(entry);
+                position = Some((file_id, range_or_offset));
+            } else {
+                res.add_file_fixture(entry);
+            }
+        }
+        (res, position)
+    }
+
+    fn add_file_fixture(&mut self, fixture: Fixture) -> FileId {
+        let file_id = FileId((self.files.len() + 1) as u32);
+        self.files.push(fixture);
+        file_id
+    }
+
+    pub fn id_of(&self, path: &str) -> FileId {
+        let (file_id, _) =
+            self.files().find(|(_, data)| path == data.path).expect("no file in this mock");
+        file_id
+    }
+    pub fn annotations(&self) -> Vec<(FileRange, String)> {
+        self.files()
+            .flat_map(|(file_id, fixture)| {
+                let annotations = extract_annotations(&fixture.text);
+                annotations
+                    .into_iter()
+                    .map(move |(range, data)| (FileRange { file_id, range }, data))
+            })
+            .collect()
+    }
+    pub fn files(&self) -> impl Iterator<Item = (FileId, &Fixture)> + '_ {
+        self.files.iter().enumerate().map(|(idx, fixture)| (FileId(idx as u32 + 1), fixture))
+    }
+    pub fn annotation(&self) -> (FileRange, String) {
+        let mut all = self.annotations();
+        assert_eq!(all.len(), 1);
+        all.pop().unwrap()
+    }
+    pub fn analysis_host(self) -> AnalysisHost {
+        let mut host = AnalysisHost::default();
+        let mut change = AnalysisChange::new();
+        let mut file_set = FileSet::default();
+        let mut crate_graph = CrateGraph::default();
+        let mut root_crate = None;
+        for (i, data) in self.files.into_iter().enumerate() {
+            let path = data.path;
+            assert!(path.starts_with('/'));
+
+            let mut cfg = CfgOptions::default();
+            data.cfg_atoms.iter().for_each(|it| cfg.insert_atom(it.into()));
+            data.cfg_key_values.iter().for_each(|(k, v)| cfg.insert_key_value(k.into(), v.into()));
+            let edition: Edition =
+                data.edition.and_then(|it| it.parse().ok()).unwrap_or(Edition::Edition2018);
+
+            let file_id = FileId(i as u32 + 1);
+            let env = data.env.into_iter().collect();
+            if path == "/lib.rs" || path == "/main.rs" {
+                root_crate = Some(crate_graph.add_crate_root(
+                    file_id,
+                    edition,
+                    Some("test".to_string()),
+                    cfg,
+                    env,
+                    Default::default(),
+                ));
+            } else if path.ends_with("/lib.rs") {
+                let base = &path[..path.len() - "/lib.rs".len()];
+                let crate_name = &base[base.rfind('/').unwrap() + '/'.len_utf8()..];
+                let other_crate = crate_graph.add_crate_root(
+                    file_id,
+                    edition,
+                    Some(crate_name.to_string()),
+                    cfg,
+                    env,
+                    Default::default(),
+                );
+                if let Some(root_crate) = root_crate {
+                    crate_graph
+                        .add_dep(root_crate, CrateName::new(crate_name).unwrap(), other_crate)
+                        .unwrap();
+                }
+            }
+            let path = VfsPath::new_virtual_path(path.to_string());
+            file_set.insert(file_id, path);
+            change.change_file(file_id, Some(Arc::new(data.text).to_owned()));
+        }
+        change.set_crate_graph(crate_graph);
+        change.set_roots(vec![SourceRoot::new_local(file_set)]);
+        host.apply_change(change);
+        host
+    }
+    pub fn analysis(self) -> Analysis {
+        self.analysis_host().analysis()
+    }
+}
+
+/// Creates analysis from a multi-file fixture, returns positions marked with <|>.
+pub fn analysis_and_position(ra_fixture: &str) -> (Analysis, FilePosition) {
+    let (mock, position) = MockAnalysis::with_files_and_position(ra_fixture);
+    (mock.analysis(), position)
+}
+
+/// Creates analysis for a single file.
+pub fn single_file(ra_fixture: &str) -> (Analysis, FileId) {
+    let mock = MockAnalysis::with_files(ra_fixture);
+    let file_id = mock.id_of("/main.rs");
+    (mock.analysis(), file_id)
+}
+
+/// Creates analysis for a single file, returns range marked with a pair of <|>.
+pub fn analysis_and_range(ra_fixture: &str) -> (Analysis, FileRange) {
+    let (res, position) = MockAnalysis::with_fixture(ra_fixture);
+    let (file_id, range_or_offset) = position.expect("expected a marker (<|>)");
+    let range = match range_or_offset {
+        RangeOrOffset::Range(it) => it,
+        RangeOrOffset::Offset(_) => panic!(),
+    };
+    (res.analysis(), FileRange { file_id, range })
+}