Add MockAnalysis to make testing easier

7 files changed, 167 insertions, 76 deletions

diff --git a/crates/ra_analysis/Cargo.toml b/crates/ra_analysis/Cargo.toml
index 892e34235..deddf41f0 100644
--- a/crates/ra_analysis/Cargo.toml
+++ b/crates/ra_analysis/Cargo.toml
@@ -9,10 +9,8 @@ log = "0.4.5"
 relative-path = "0.4.0"
 rayon = "1.0.2"
 fst = "0.3.1"
-ra_syntax = { path = "../ra_syntax" }
-ra_editor = { path = "../ra_editor" }
 salsa = "0.7.0"
 rustc-hash = "1.0"
-
-[dev-dependencies]
+ra_syntax = { path = "../ra_syntax" }
+ra_editor = { path = "../ra_editor" }
 test_utils = { path = "../test_utils" }
diff --git a/crates/ra_analysis/src/completion.rs b/crates/ra_analysis/src/completion.rs
index 340ae3f66..286b6c376 100644
--- a/crates/ra_analysis/src/completion.rs
+++ b/crates/ra_analysis/src/completion.rs
@@ -368,18 +368,15 @@ fn complete_fn(name_ref: ast::NameRef, scopes: &FnScopes, acc: &mut Vec<Completi
 
 #[cfg(test)]
 mod tests {
-    use test_utils::{assert_eq_dbg, extract_offset};
+    use test_utils::{assert_eq_dbg};
 
-    use crate::FileId;
-    use crate::mock_analysis::MockAnalysis;
+    use crate::mock_analysis::{single_file_with_position};
 
     use super::*;
 
     fn check_scope_completion(code: &str, expected_completions: &str) {
-        let (off, code) = extract_offset(&code);
-        let analysis = MockAnalysis::with_files(&[("/main.rs", &code)]).analysis();
-        let file_id = FileId(1);
-        let completions = scope_completion(&analysis.imp.db, file_id, off)
+        let (analysis, position) = single_file_with_position(code);
+        let completions = scope_completion(&analysis.imp.db, position.file_id, position.offset)
             .unwrap()
             .into_iter()
             .filter(|c| c.snippet.is_none())
@@ -388,10 +385,8 @@ mod tests {
     }
 
     fn check_snippet_completion(code: &str, expected_completions: &str) {
-        let (off, code) = extract_offset(&code);
-        let analysis = MockAnalysis::with_files(&[("/main.rs", &code)]).analysis();
-        let file_id = FileId(1);
-        let completions = scope_completion(&analysis.imp.db, file_id, off)
+        let (analysis, position) = single_file_with_position(code);
+        let completions = scope_completion(&analysis.imp.db, position.file_id, position.offset)
             .unwrap()
             .into_iter()
             .filter(|c| c.snippet.is_some())
diff --git a/crates/ra_analysis/src/input.rs b/crates/ra_analysis/src/input.rs
index fd63182c7..b89b45133 100644
--- a/crates/ra_analysis/src/input.rs
+++ b/crates/ra_analysis/src/input.rs
@@ -25,7 +25,7 @@ impl CrateGraph {
     pub fn new() -> CrateGraph {
         CrateGraph::default()
     }
-    pub fn add_crate_root(&mut self, file_id: FileId) -> CrateId{
+    pub fn add_crate_root(&mut self, file_id: FileId) -> CrateId {
         let crate_id = CrateId(self.crate_roots.len() as u32);
         let prev = self.crate_roots.insert(crate_id, file_id);
         assert!(prev.is_none());
diff --git a/crates/ra_analysis/src/lib.rs b/crates/ra_analysis/src/lib.rs
index 776010281..e75411ec9 100644
--- a/crates/ra_analysis/src/lib.rs
+++ b/crates/ra_analysis/src/lib.rs
@@ -13,7 +13,7 @@ mod imp;
 mod symbol_index;
 mod completion;
 mod syntax_ptr;
-mod mock_analysis;
+pub mod mock_analysis;
 
 use std::{
     fmt,
@@ -33,7 +33,6 @@ pub use crate::{
     descriptors::function::FnDescriptor,
     completion::CompletionItem,
     input::{FileId, FileResolver, CrateGraph, CrateId},
-    mock_analysis::MockAnalysis,
 };
 pub use ra_editor::{
     FileSymbol, Fold, FoldKind, HighlightedRange, LineIndex, Runnable,
diff --git a/crates/ra_analysis/src/mock_analysis.rs b/crates/ra_analysis/src/mock_analysis.rs
index 1c1dbee7c..f72911192 100644
--- a/crates/ra_analysis/src/mock_analysis.rs
+++ b/crates/ra_analysis/src/mock_analysis.rs
@@ -2,11 +2,19 @@
 use std::sync::Arc;
 
 use relative_path::{RelativePath, RelativePathBuf};
+use ra_syntax::TextUnit;
+use test_utils::{extract_offset, parse_fixture, CURSOR_MARKER};
 
 use crate::{
     AnalysisChange, Analysis, AnalysisHost, FileId, FileResolver,
 };
 
+#[derive(Debug)]
+pub struct FilePosition {
+    pub file_id: FileId,
+    pub offset: TextUnit,
+}
+
 /// Mock analysis is used in test to bootstrap an AnalysisHost/Analysis
 /// from a set of in-memory files.
 #[derive(Debug, Default)]
@@ -18,11 +26,57 @@ impl MockAnalysis {
     pub fn new() -> MockAnalysis {
         MockAnalysis::default()
     }
-    pub fn with_files(files: &[(&str, &str)]) -> MockAnalysis {
-        let files = files.iter()
-            .map(|it| (it.0.to_string(), it.1.to_string()))
-            .collect();
-        MockAnalysis { files }
+    /// Creates `MockAnalysis` using a fixture data in the following format:
+    ///
+    /// ```notrust
+    /// //- /main.rs
+    /// mod foo;
+    /// fn main() {}
+    ///
+    /// //- /foo.rs
+    /// struct Baz;
+    /// ```
+    pub fn with_files(fixture: &str) -> MockAnalysis {
+        let mut res = MockAnalysis::new();
+        for entry in parse_fixture(fixture) {
+            res.add_file(&entry.meta, &entry.text);
+        }
+        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 mut position = None;
+        let mut res = MockAnalysis::new();
+        for entry in parse_fixture(fixture) {
+            if entry.text.contains(CURSOR_MARKER) {
+                assert!(position.is_none(), "only one marker (<|>) per fixture is allowed");
+                position = Some(res.add_file_with_position(&entry.meta, &entry.text));
+            } else {
+                res.add_file(&entry.meta, &entry.text);
+            }
+        }
+        let position = position.expect("expected a marker (<|>)");
+        (res, position)
+    }
+
+    pub fn add_file(&mut self, path: &str, text: &str) -> FileId {
+        let file_id = FileId((self.files.len() + 1) as u32);
+        self.files.push((path.to_string(), text.to_string()));
+        file_id
+    }
+    pub fn add_file_with_position(&mut self, path: &str, text: &str) -> FilePosition {
+        let (offset, text) = extract_offset(text);
+        let file_id = FileId((self.files.len() + 1) as u32);
+        self.files.push((path.to_string(), text.to_string()));
+        FilePosition { file_id, offset }
+    }
+    pub fn id_of(&self, path: &str) -> FileId {
+        let (idx, _) = self.files.iter().enumerate()
+            .find(|(_, (p, _text))| path == p)
+            .expect("no file in this mock");
+        FileId(idx as u32 + 1)
     }
     pub fn analysis_host(self) -> AnalysisHost {
         let mut host = AnalysisHost::new();
@@ -44,6 +98,26 @@ impl MockAnalysis {
     }
 }
 
+/// Creates analysis from a multi-file fixture, returns positions marked with <|>.
+pub fn analysis_and_position(fixture: &str) -> (Analysis, FilePosition) {
+    let (mock, position) = MockAnalysis::with_files_and_position(fixture);
+    (mock.analysis(), position)
+}
+
+/// Creates analysis for a single file.
+pub fn single_file(code: &str) -> (Analysis, FileId) {
+    let mut mock = MockAnalysis::new();
+    let file_id = mock.add_file("/main.rs", code);
+    (mock.analysis(), file_id)
+}
+
+/// Creates analysis for a single file, returns position marked with <|>.
+pub fn single_file_with_position(code: &str) -> (Analysis, FilePosition) {
+    let mut mock = MockAnalysis::new();
+    let pos = mock.add_file_with_position("/main.rs", code);
+    (mock.analysis(), pos)
+}
+
 #[derive(Debug)]
 struct FileMap(Vec<(FileId, RelativePathBuf)>);
 
diff --git a/crates/ra_analysis/tests/tests.rs b/crates/ra_analysis/tests/tests.rs
index f5683aec5..94e025677 100644
--- a/crates/ra_analysis/tests/tests.rs
+++ b/crates/ra_analysis/tests/tests.rs
@@ -5,38 +5,42 @@ extern crate relative_path;
 extern crate rustc_hash;
 extern crate test_utils;
 
-use ra_syntax::TextRange;
-use test_utils::{assert_eq_dbg, extract_offset};
+use ra_syntax::{TextRange};
+use test_utils::{assert_eq_dbg};
 
 use ra_analysis::{
-    MockAnalysis,
-    AnalysisChange, Analysis, CrateGraph, CrateId, FileId, FnDescriptor,
+    AnalysisChange, CrateGraph, FileId, FnDescriptor,
+    mock_analysis::{MockAnalysis, single_file, single_file_with_position, analysis_and_position},
 };
 
-fn analysis(files: &[(&str, &str)]) -> Analysis {
-    MockAnalysis::with_files(files).analysis()
-}
-
 fn get_signature(text: &str) -> (FnDescriptor, Option<usize>) {
-    let (offset, code) = extract_offset(text);
-    let code = code.as_str();
-
-    let snap = analysis(&[("/lib.rs", code)]);
-
-    snap.resolve_callable(FileId(1), offset).unwrap().unwrap()
+    let (analysis, position) = single_file_with_position(text);
+    analysis.resolve_callable(position.file_id, position.offset).unwrap().unwrap()
 }
 
 #[test]
 fn test_resolve_module() {
-    let snap = analysis(&[("/lib.rs", "mod foo;"), ("/foo.rs", "")]);
-    let symbols = snap.approximately_resolve_symbol(FileId(1), 4.into()).unwrap();
+    let (analysis, pos) = analysis_and_position("
+        //- /lib.rs
+        mod <|>foo;
+        //- /foo.rs
+        // empty
+    ");
+
+    let symbols = analysis.approximately_resolve_symbol(pos.file_id, pos.offset).unwrap();
     assert_eq_dbg(
         r#"[(FileId(2), FileSymbol { name: "foo", node_range: [0; 0), kind: MODULE })]"#,
         &symbols,
     );
 
-    let snap = analysis(&[("/lib.rs", "mod foo;"), ("/foo/mod.rs", "")]);
-    let symbols = snap.approximately_resolve_symbol(FileId(1), 4.into()).unwrap();
+    let (analysis, pos) = analysis_and_position("
+        //- /lib.rs
+        mod <|>foo;
+        //- /foo/mod.rs
+        // empty
+    ");
+
+    let symbols = analysis.approximately_resolve_symbol(pos.file_id, pos.offset).unwrap();
     assert_eq_dbg(
         r#"[(FileId(2), FileSymbol { name: "foo", node_range: [0; 0), kind: MODULE })]"#,
         &symbols,
@@ -45,8 +49,8 @@ fn test_resolve_module() {
 
 #[test]
 fn test_unresolved_module_diagnostic() {
-    let snap = analysis(&[("/lib.rs", "mod foo;")]);
-    let diagnostics = snap.diagnostics(FileId(1)).unwrap();
+    let (analysis, file_id) = single_file("mod foo;");
+    let diagnostics = analysis.diagnostics(file_id).unwrap();
     assert_eq_dbg(
         r#"[Diagnostic {
             message: "unresolved module",
@@ -62,15 +66,20 @@ fn test_unresolved_module_diagnostic() {
 
 #[test]
 fn test_unresolved_module_diagnostic_no_diag_for_inline_mode() {
-    let snap = analysis(&[("/lib.rs", "mod foo {}")]);
-    let diagnostics = snap.diagnostics(FileId(1)).unwrap();
+    let (analysis, file_id) = single_file("mod foo {}");
+    let diagnostics = analysis.diagnostics(file_id).unwrap();
     assert_eq_dbg(r#"[]"#, &diagnostics);
 }
 
 #[test]
 fn test_resolve_parent_module() {
-    let snap = analysis(&[("/lib.rs", "mod foo;"), ("/foo.rs", "")]);
-    let symbols = snap.parent_module(FileId(2)).unwrap();
+    let (analysis, pos) = analysis_and_position("
+        //- /lib.rs
+        mod foo;
+        //- /foo.rs
+        <|>// empty
+    ");
+    let symbols = analysis.parent_module(pos.file_id).unwrap();
     assert_eq_dbg(
         r#"[(FileId(1), FileSymbol { name: "foo", node_range: [0; 8), kind: MODULE })]"#,
         &symbols,
@@ -79,23 +88,24 @@ fn test_resolve_parent_module() {
 
 #[test]
 fn test_resolve_crate_root() {
-    let mut host = MockAnalysis::with_files(
-        &[("/lib.rs", "mod foo;"), ("/foo.rs", "")]
-    ).analysis_host();
-    let snap = host.analysis();
-    assert!(snap.crate_for(FileId(2)).unwrap().is_empty());
-
-    let crate_graph = {
-        let mut g = CrateGraph::new();
-        g.add_crate_root(FileId(1));
-        g
-    };
+    let mock = MockAnalysis::with_files("
+        //- /lib.rs
+        mod foo;
+        //- /foo.rs
+        // emtpy <|>
+    ");
+    let root_file = mock.id_of("/lib.rs");
+    let mod_file = mock.id_of("/foo.rs");
+    let mut host = mock.analysis_host();
+    assert!(host.analysis().crate_for(mod_file).unwrap().is_empty());
+
+    let mut crate_graph = CrateGraph::new();
+    let crate_id = crate_graph.add_crate_root(root_file);
     let mut change = AnalysisChange::new();
     change.set_crate_graph(crate_graph);
     host.apply_change(change);
-    let snap = host.analysis();
 
-    assert_eq!(snap.crate_for(FileId(2)).unwrap(), vec![CrateId(0)],);
+    assert_eq!(host.analysis().crate_for(mod_file).unwrap(), vec![crate_id]);
 }
 
 #[test]
@@ -186,12 +196,8 @@ fn bar() {
 }
 
 fn get_all_refs(text: &str) -> Vec<(FileId, TextRange)> {
-    let (offset, code) = extract_offset(text);
-    let code = code.as_str();
-
-    let snap = analysis(&[("/lib.rs", code)]);
-
-    snap.find_all_refs(FileId(1), offset).unwrap()
+    let (analysis, position) = single_file_with_position(text);
+    analysis.find_all_refs(position.file_id, position.offset).unwrap()
 }
 
 #[test]
@@ -226,11 +232,14 @@ fn test_find_all_refs_for_param_inside() {
 
 #[test]
 fn test_complete_crate_path() {
-    let snap = analysis(&[
-        ("/lib.rs", "mod foo; struct Spam;"),
-        ("/foo.rs", "use crate::Sp"),
-    ]);
-    let completions = snap.completions(FileId(2), 13.into()).unwrap().unwrap();
+    let (analysis, position) = analysis_and_position("
+        //- /lib.rs
+        mod foo;
+        struct Spam;
+        //- /foo.rs
+        use crate::Sp<|>
+    ");
+    let completions = analysis.completions(position.file_id, position.offset).unwrap().unwrap();
     assert_eq_dbg(
         r#"[CompletionItem { label: "foo", lookup: None, snippet: None },
             CompletionItem { label: "Spam", lookup: None, snippet: None }]"#,
diff --git a/crates/test_utils/src/lib.rs b/crates/test_utils/src/lib.rs
index 562dbcbb3..8980f077f 100644
--- a/crates/test_utils/src/lib.rs
+++ b/crates/test_utils/src/lib.rs
@@ -8,6 +8,8 @@ use text_unit::{TextRange, TextUnit};
 
 pub use self::difference::Changeset as __Changeset;
 
+pub const CURSOR_MARKER: &str = "<|>";
+
 #[macro_export]
 macro_rules! assert_eq_text {
     ($expected:expr, $actual:expr) => {{
@@ -45,11 +47,10 @@ pub fn extract_offset(text: &str) -> (TextUnit, String) {
 }
 
 pub fn try_extract_offset(text: &str) -> Option<(TextUnit, String)> {
-    let cursor = "<|>";
-    let cursor_pos = text.find(cursor)?;
-    let mut new_text = String::with_capacity(text.len() - cursor.len());
+    let cursor_pos = text.find(CURSOR_MARKER)?;
+    let mut new_text = String::with_capacity(text.len() - CURSOR_MARKER.len());
     new_text.push_str(&text[..cursor_pos]);
-    new_text.push_str(&text[cursor_pos + cursor.len()..]);
+    new_text.push_str(&text[cursor_pos + CURSOR_MARKER.len()..]);
     let cursor_pos = TextUnit::from(cursor_pos as u32);
     Some((cursor_pos, new_text))
 }
@@ -116,7 +117,22 @@ pub fn parse_fixture(fixture: &str) -> Vec<FixtureEntry> {
             }
         };
     };
-    for line in fixture.lines() {
+    let margin = fixture.lines()
+        .filter(|it| it.trim_start().starts_with("//-"))
+        .map(|it| it.len() - it.trim_start().len())
+        .next().expect("empty fixture");
+    let lines = fixture.lines()
+        .filter_map(|line| {
+            if line.len() >= margin {
+                assert!(line[..margin].trim().is_empty());
+                Some(&line[margin..])
+            } else {
+                assert!(line.trim().is_empty());
+                None
+            }
+        });
+
+    for line in lines {
         if line.starts_with("//-") {
             flush!();
             buf.clear();