Add testing infrastructure for type inference

 - move dir_tests to test_utils for that.

5 files changed, 102 insertions, 23 deletions

diff --git a/crates/ra_hir/src/mock.rs b/crates/ra_hir/src/mock.rs
index a9fa540d5..3020ee793 100644
--- a/crates/ra_hir/src/mock.rs
+++ b/crates/ra_hir/src/mock.rs
@@ -24,6 +24,15 @@ impl MockDatabase {
         (db, source_root)
     }
 
+    pub(crate) fn with_single_file(text: &str) -> (MockDatabase, SourceRoot, FileId) {
+        let mut db = MockDatabase::default();
+        let mut source_root = SourceRoot::default();
+        let file_id = db.add_file(&mut source_root, "/main.rs", text);
+        db.query_mut(ra_db::SourceRootQuery)
+            .set(WORKSPACE, Arc::new(source_root.clone()));
+        (db, source_root, file_id)
+    }
+
     pub(crate) fn with_position(fixture: &str) -> (MockDatabase, FilePosition) {
         let (db, _, position) = MockDatabase::from_fixture(fixture);
         let position = position.expect("expected a marker ( <|> )");
diff --git a/crates/ra_hir/src/ty.rs b/crates/ra_hir/src/ty.rs
index 087385b98..66b204dcd 100644
--- a/crates/ra_hir/src/ty.rs
+++ b/crates/ra_hir/src/ty.rs
@@ -6,6 +6,7 @@ use rustc_hash::{FxHashMap, FxHashSet};
 
 use std::sync::Arc;
 use std::collections::HashMap;
+use std::fmt;
 
 use ra_db::LocalSyntaxPtr;
 use ra_syntax::{
@@ -184,11 +185,40 @@ impl Ty {
     }
 }
 
+impl fmt::Display for Ty {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        match self {
+            Ty::Bool => write!(f, "bool"),
+            Ty::Char => write!(f, "char"),
+            Ty::Int(t) => write!(f, "{}", t.ty_to_string()),
+            Ty::Uint(t) => write!(f, "{}", t.ty_to_string()),
+            Ty::Float(t) => write!(f, "{}", t.ty_to_string()),
+            Ty::Str => write!(f, "str"),
+            Ty::Slice(t) => write!(f, "[{}]", t),
+            Ty::Never => write!(f, "!"),
+            Ty::Tuple(ts) => {
+                write!(f, "(")?;
+                for t in ts {
+                    write!(f, "{},", t)?;
+                }
+                write!(f, ")")
+            }
+            Ty::Unknown => write!(f, "[unknown]")
+        }
+    }
+}
+
 #[derive(Clone, PartialEq, Eq, Debug)]
 pub struct InferenceResult {
     type_for: FxHashMap<LocalSyntaxPtr, Ty>,
 }
 
+impl InferenceResult {
+    pub fn type_of_node(&self, node: SyntaxNodeRef) -> Option<Ty> {
+        self.type_for.get(&LocalSyntaxPtr::new(node)).cloned()
+    }
+}
+
 #[derive(Clone, PartialEq, Eq, Debug)]
 pub struct InferenceContext {
     scopes: Arc<FnScopes>,
diff --git a/crates/ra_hir/src/ty/tests.rs b/crates/ra_hir/src/ty/tests.rs
index f2466dd51..98eedaa3f 100644
--- a/crates/ra_hir/src/ty/tests.rs
+++ b/crates/ra_hir/src/ty/tests.rs
@@ -1,8 +1,11 @@
+use std::fmt::Write;
 use std::sync::Arc;
+use std::path::{Path, PathBuf};
 
 use salsa::Database;
 use ra_db::{FilesDatabase, CrateGraph, SyntaxDatabase};
 use ra_syntax::{SmolStr, algo::visit::{visitor, Visitor}, ast::{self, AstNode}};
+use test_utils::{project_dir, dir_tests};
 use relative_path::RelativePath;
 
 use crate::{source_binder, mock::WORKSPACE, module::ModuleSourceNode};
@@ -13,33 +16,46 @@ use crate::{
     mock::MockDatabase,
 };
 
-fn infer_all_fns(fixture: &str) -> () {
-    let (db, source_root) = MockDatabase::with_files(fixture);
-    for &file_id in source_root.files.values() {
-        let source_file = db.source_file(file_id);
-        for fn_def in source_file.syntax().descendants().filter_map(ast::FnDef::cast) {
-            let func = source_binder::function_from_source(&db, file_id, fn_def).unwrap().unwrap();
-            let inference_result = func.infer(&db);
-            for (syntax_ptr, ty) in &inference_result.type_for {
-                let node = syntax_ptr.resolve(&source_file);
-                eprintln!("{} '{}': {:?}", syntax_ptr.range(), node.text(), ty);
-            }
+fn infer_file(content: &str) -> String {
+    let (db, source_root, file_id) = MockDatabase::with_single_file(content);
+    let source_file = db.source_file(file_id);
+    let mut acc = String::new();
+    for fn_def in source_file.syntax().descendants().filter_map(ast::FnDef::cast) {
+        let func = source_binder::function_from_source(&db, file_id, fn_def).unwrap().unwrap();
+        let inference_result = func.infer(&db);
+        for (syntax_ptr, ty) in &inference_result.type_for {
+            let node = syntax_ptr.resolve(&source_file);
+            write!(acc, "{} '{}': {}\n", syntax_ptr.range(), ellipsize(node.text().to_string().replace("\n", " "), 15), ty);
         }
     }
+    acc
+}
+
+fn ellipsize(mut text: String, max_len: usize) -> String {
+    if text.len() <= max_len {
+        return text;
+    }
+    let ellipsis = "...";
+    let e_len = ellipsis.len();
+    let mut prefix_len = (max_len - e_len) / 2;
+    while !text.is_char_boundary(prefix_len) {
+        prefix_len += 1;
+    }
+    let mut suffix_len = max_len - e_len - prefix_len;
+    while !text.is_char_boundary(text.len() - suffix_len) {
+        suffix_len += 1;
+    }
+    text.replace_range(prefix_len..text.len() - suffix_len, ellipsis);
+    text
 }
 
 #[test]
-fn infer_smoke_test() {
-    let text = "
-        //- /lib.rs
-        fn foo(x: u32, y: !) -> i128 {
-            x;
-            y;
-            return 1;
-            \"hello\";
-            0
-        }
-    ";
+pub fn infer_tests() {
+    dir_tests(&test_data_dir(), &["."], |text, _path| {
+        infer_file(text)
+    });
+}
 
-    infer_all_fns(text);
+fn test_data_dir() -> PathBuf {
+    project_dir().join("crates/ra_hir/src/ty/tests/data")
 }
diff --git a/crates/ra_hir/src/ty/tests/data/0001_basics.rs b/crates/ra_hir/src/ty/tests/data/0001_basics.rs
new file mode 100644
index 000000000..59a60d031
--- /dev/null
+++ b/crates/ra_hir/src/ty/tests/data/0001_basics.rs
@@ -0,0 +1,11 @@
+
+fn test(a: u32, b: isize, c: !, d: &str) {
+    a;
+    b;
+    c;
+    d;
+    1usize;
+    1isize;
+    "test";
+    1.0f32;
+}
diff --git a/crates/ra_hir/src/ty/tests/data/0001_basics.txt b/crates/ra_hir/src/ty/tests/data/0001_basics.txt
new file mode 100644
index 000000000..0c46f243a
--- /dev/null
+++ b/crates/ra_hir/src/ty/tests/data/0001_basics.txt
@@ -0,0 +1,13 @@
+[33; 34) 'd': [unknown]
+[88; 94) '1isize': [unknown]
+[48; 49) 'a': u32
+[55; 56) 'b': isize
+[112; 118) '1.0f32': [unknown]
+[76; 82) '1usize': [unknown]
+[9; 10) 'a': u32
+[27; 28) 'c': !
+[62; 63) 'c': !
+[17; 18) 'b': isize
+[100; 106) '"test"': [unknown]
+[42; 121) '{     ...f32; }': ()
+[69; 70) 'd': [unknown]