diff --git a/crates/ra_analysis/src/call_info.rs b/crates/ra_analysis/src/call_info.rs
index 8da19a648adf..2fcd03c9be8d 100644
--- a/crates/ra_analysis/src/call_info.rs
+++ b/crates/ra_analysis/src/call_info.rs
@@ -128,3 +128,252 @@ impl<'a> FnCallNode<'a> {
         }
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    use crate::mock_analysis::single_file_with_position;
+
+    fn call_info(text: &str) -> CallInfo {
+        let (analysis, position) = single_file_with_position(text);
+        analysis.call_info(position).unwrap().unwrap()
+    }
+
+    #[test]
+    fn test_fn_signature_two_args_first() {
+        let info = call_info(
+            r#"fn foo(x: u32, y: u32) -> u32 {x + y}
+fn bar() { foo(<|>3, ); }"#,
+        );
+
+        assert_eq!(info.parameters, vec!("x".to_string(), "y".to_string()));
+        assert_eq!(info.active_parameter, Some(0));
+    }
+
+    #[test]
+    fn test_fn_signature_two_args_second() {
+        let info = call_info(
+            r#"fn foo(x: u32, y: u32) -> u32 {x + y}
+fn bar() { foo(3, <|>); }"#,
+        );
+
+        assert_eq!(info.parameters, vec!("x".to_string(), "y".to_string()));
+        assert_eq!(info.active_parameter, Some(1));
+    }
+
+    #[test]
+    fn test_fn_signature_for_impl() {
+        let info = call_info(
+            r#"struct F; impl F { pub fn new() { F{}} }
+fn bar() {let _ : F = F::new(<|>);}"#,
+        );
+
+        assert_eq!(info.parameters, Vec::<String>::new());
+        assert_eq!(info.active_parameter, None);
+    }
+
+    #[test]
+    fn test_fn_signature_for_method_self() {
+        let info = call_info(
+            r#"struct F;
+impl F {
+    pub fn new() -> F{
+        F{}
+    }
+
+    pub fn do_it(&self) {}
+}
+
+fn bar() {
+    let f : F = F::new();
+    f.do_it(<|>);
+}"#,
+        );
+
+        assert_eq!(info.parameters, vec!["&self".to_string()]);
+        assert_eq!(info.active_parameter, None);
+    }
+
+    #[test]
+    fn test_fn_signature_for_method_with_arg() {
+        let info = call_info(
+            r#"struct F;
+impl F {
+    pub fn new() -> F{
+        F{}
+    }
+
+    pub fn do_it(&self, x: i32) {}
+}
+
+fn bar() {
+    let f : F = F::new();
+    f.do_it(<|>);
+}"#,
+        );
+
+        assert_eq!(info.parameters, vec!["&self".to_string(), "x".to_string()]);
+        assert_eq!(info.active_parameter, Some(1));
+    }
+
+    #[test]
+    fn test_fn_signature_with_docs_simple() {
+        let info = call_info(
+            r#"
+/// test
+// non-doc-comment
+fn foo(j: u32) -> u32 {
+    j
+}
+
+fn bar() {
+    let _ = foo(<|>);
+}
+"#,
+        );
+
+        assert_eq!(info.parameters, vec!["j".to_string()]);
+        assert_eq!(info.active_parameter, Some(0));
+        assert_eq!(info.label, "fn foo(j: u32) -> u32".to_string());
+        assert_eq!(info.doc, Some("test".into()));
+    }
+
+    #[test]
+    fn test_fn_signature_with_docs() {
+        let info = call_info(
+            r#"
+/// Adds one to the number given.
+///
+/// # Examples
+///
+/// ```
+/// let five = 5;
+///
+/// assert_eq!(6, my_crate::add_one(5));
+/// ```
+pub fn add_one(x: i32) -> i32 {
+    x + 1
+}
+
+pub fn do() {
+    add_one(<|>
+}"#,
+        );
+
+        assert_eq!(info.parameters, vec!["x".to_string()]);
+        assert_eq!(info.active_parameter, Some(0));
+        assert_eq!(info.label, "pub fn add_one(x: i32) -> i32".to_string());
+        assert_eq!(
+            info.doc,
+            Some(
+                r#"Adds one to the number given.
+
+# Examples
+
+```rust
+let five = 5;
+
+assert_eq!(6, my_crate::add_one(5));
+```"#
+                    .into()
+            )
+        );
+    }
+
+    #[test]
+    fn test_fn_signature_with_docs_impl() {
+        let info = call_info(
+            r#"
+struct addr;
+impl addr {
+    /// Adds one to the number given.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// let five = 5;
+    ///
+    /// assert_eq!(6, my_crate::add_one(5));
+    /// ```
+    pub fn add_one(x: i32) -> i32 {
+        x + 1
+    }
+}
+
+pub fn do_it() {
+    addr {};
+    addr::add_one(<|>);
+}"#,
+        );
+
+        assert_eq!(info.parameters, vec!["x".to_string()]);
+        assert_eq!(info.active_parameter, Some(0));
+        assert_eq!(info.label, "pub fn add_one(x: i32) -> i32".to_string());
+        assert_eq!(
+            info.doc,
+            Some(
+                r#"Adds one to the number given.
+
+# Examples
+
+```rust
+let five = 5;
+
+assert_eq!(6, my_crate::add_one(5));
+```"#
+                    .into()
+            )
+        );
+    }
+
+    #[test]
+    fn test_fn_signature_with_docs_from_actix() {
+        let info = call_info(
+            r#"
+pub trait WriteHandler<E>
+where
+    Self: Actor,
+    Self::Context: ActorContext,
+{
+    /// Method is called when writer emits error.
+    ///
+    /// If this method returns `ErrorAction::Continue` writer processing
+    /// continues otherwise stream processing stops.
+    fn error(&mut self, err: E, ctx: &mut Self::Context) -> Running {
+        Running::Stop
+    }
+
+    /// Method is called when writer finishes.
+    ///
+    /// By default this method stops actor's `Context`.
+    fn finished(&mut self, ctx: &mut Self::Context) {
+        ctx.stop()
+    }
+}
+
+pub fn foo() {
+    WriteHandler r;
+    r.finished(<|>);
+}
+
+"#,
+        );
+
+        assert_eq!(
+            info.parameters,
+            vec!["&mut self".to_string(), "ctx".to_string()]
+        );
+        assert_eq!(info.active_parameter, Some(1));
+        assert_eq!(
+            info.doc,
+            Some(
+                r#"Method is called when writer finishes.
+
+By default this method stops actor's `Context`."#
+                    .into()
+            )
+        );
+    }
+
+}
diff --git a/crates/ra_analysis/tests/test/main.rs b/crates/ra_analysis/tests/test/main.rs
index 1f70af12aa67..2c0735cb50cf 100644
--- a/crates/ra_analysis/tests/test/main.rs
+++ b/crates/ra_analysis/tests/test/main.rs
@@ -5,14 +5,9 @@ use test_utils::{assert_eq_dbg, assert_eq_text};
 
 use ra_analysis::{
     mock_analysis::{analysis_and_position, single_file, single_file_with_position, MockAnalysis},
-    AnalysisChange, CrateGraph, FileId, FnSignatureInfo, Query
+    AnalysisChange, CrateGraph, FileId, Query
 };
 
-fn get_signature(text: &str) -> (FnSignatureInfo, Option<usize>) {
-    let (analysis, position) = single_file_with_position(text);
-    analysis.resolve_callable(position).unwrap().unwrap()
-}
-
 #[test]
 fn test_unresolved_module_diagnostic() {
     let (analysis, file_id) = single_file("mod foo;");
@@ -99,260 +94,6 @@ fn test_resolve_crate_root() {
     assert_eq!(host.analysis().crate_for(mod_file).unwrap(), vec![crate_id]);
 }
 
-#[test]
-fn test_fn_signature_two_args_first() {
-    let (desc, param) = get_signature(
-        r#"fn foo(x: u32, y: u32) -> u32 {x + y}
-fn bar() { foo(<|>3, ); }"#,
-    );
-
-    assert_eq!(desc.name, "foo".to_string());
-    assert_eq!(desc.params, vec!("x".to_string(), "y".to_string()));
-    assert_eq!(desc.ret_type, Some("-> u32".into()));
-    assert_eq!(param, Some(0));
-}
-
-#[test]
-fn test_fn_signature_two_args_second() {
-    let (desc, param) = get_signature(
-        r#"fn foo(x: u32, y: u32) -> u32 {x + y}
-fn bar() { foo(3, <|>); }"#,
-    );
-
-    assert_eq!(desc.name, "foo".to_string());
-    assert_eq!(desc.params, vec!("x".to_string(), "y".to_string()));
-    assert_eq!(desc.ret_type, Some("-> u32".into()));
-    assert_eq!(param, Some(1));
-}
-
-#[test]
-fn test_fn_signature_for_impl() {
-    let (desc, param) = get_signature(
-        r#"struct F; impl F { pub fn new() { F{}} }
-fn bar() {let _ : F = F::new(<|>);}"#,
-    );
-
-    assert_eq!(desc.name, "new".to_string());
-    assert_eq!(desc.params, Vec::<String>::new());
-    assert_eq!(desc.ret_type, None);
-    assert_eq!(param, None);
-}
-
-#[test]
-fn test_fn_signature_for_method_self() {
-    let (desc, param) = get_signature(
-        r#"struct F;
-impl F {
-    pub fn new() -> F{
-        F{}
-    }
-
-    pub fn do_it(&self) {}
-}
-
-fn bar() {
-    let f : F = F::new();
-    f.do_it(<|>);
-}"#,
-    );
-
-    assert_eq!(desc.name, "do_it".to_string());
-    assert_eq!(desc.params, vec!["&self".to_string()]);
-    assert_eq!(desc.ret_type, None);
-    assert_eq!(param, None);
-}
-
-#[test]
-fn test_fn_signature_for_method_with_arg() {
-    let (desc, param) = get_signature(
-        r#"struct F;
-impl F {
-    pub fn new() -> F{
-        F{}
-    }
-
-    pub fn do_it(&self, x: i32) {}
-}
-
-fn bar() {
-    let f : F = F::new();
-    f.do_it(<|>);
-}"#,
-    );
-
-    assert_eq!(desc.name, "do_it".to_string());
-    assert_eq!(desc.params, vec!["&self".to_string(), "x".to_string()]);
-    assert_eq!(desc.ret_type, None);
-    assert_eq!(param, Some(1));
-}
-
-#[test]
-fn test_fn_signature_with_docs_simple() {
-    let (desc, param) = get_signature(
-        r#"
-/// test
-// non-doc-comment
-fn foo(j: u32) -> u32 {
-    j
-}
-
-fn bar() {
-    let _ = foo(<|>);
-}
-"#,
-    );
-
-    assert_eq!(desc.name, "foo".to_string());
-    assert_eq!(desc.params, vec!["j".to_string()]);
-    assert_eq!(desc.ret_type, Some("-> u32".to_string()));
-    assert_eq!(param, Some(0));
-    assert_eq!(desc.label, "fn foo(j: u32) -> u32".to_string());
-    assert_eq!(desc.doc, Some("test".into()));
-}
-
-#[test]
-fn test_fn_signature_with_docs() {
-    let (desc, param) = get_signature(
-        r#"
-/// Adds one to the number given.
-///
-/// # Examples
-///
-/// ```
-/// let five = 5;
-///
-/// assert_eq!(6, my_crate::add_one(5));
-/// ```
-pub fn add_one(x: i32) -> i32 {
-    x + 1
-}
-
-pub fn do() {
-    add_one(<|>
-}"#,
-    );
-
-    assert_eq!(desc.name, "add_one".to_string());
-    assert_eq!(desc.params, vec!["x".to_string()]);
-    assert_eq!(desc.ret_type, Some("-> i32".to_string()));
-    assert_eq!(param, Some(0));
-    assert_eq!(desc.label, "pub fn add_one(x: i32) -> i32".to_string());
-    assert_eq!(
-        desc.doc,
-        Some(
-            r#"Adds one to the number given.
-
-# Examples
-
-```rust
-let five = 5;
-
-assert_eq!(6, my_crate::add_one(5));
-```"#
-                .into()
-        )
-    );
-}
-
-#[test]
-fn test_fn_signature_with_docs_impl() {
-    let (desc, param) = get_signature(
-        r#"
-struct addr;
-impl addr {
-    /// Adds one to the number given.
-    ///
-    /// # Examples
-    ///
-    /// ```
-    /// let five = 5;
-    ///
-    /// assert_eq!(6, my_crate::add_one(5));
-    /// ```
-    pub fn add_one(x: i32) -> i32 {
-        x + 1
-    }
-}
-
-pub fn do_it() {
-    addr {};
-    addr::add_one(<|>);
-}"#,
-    );
-
-    assert_eq!(desc.name, "add_one".to_string());
-    assert_eq!(desc.params, vec!["x".to_string()]);
-    assert_eq!(desc.ret_type, Some("-> i32".to_string()));
-    assert_eq!(param, Some(0));
-    assert_eq!(desc.label, "pub fn add_one(x: i32) -> i32".to_string());
-    assert_eq!(
-        desc.doc,
-        Some(
-            r#"Adds one to the number given.
-
-# Examples
-
-```rust
-let five = 5;
-
-assert_eq!(6, my_crate::add_one(5));
-```"#
-                .into()
-        )
-    );
-}
-
-#[test]
-fn test_fn_signature_with_docs_from_actix() {
-    let (desc, param) = get_signature(
-        r#"
-pub trait WriteHandler<E>
-where
-    Self: Actor,
-    Self::Context: ActorContext,
-{
-    /// Method is called when writer emits error.
-    ///
-    /// If this method returns `ErrorAction::Continue` writer processing
-    /// continues otherwise stream processing stops.
-    fn error(&mut self, err: E, ctx: &mut Self::Context) -> Running {
-        Running::Stop
-    }
-
-    /// Method is called when writer finishes.
-    ///
-    /// By default this method stops actor's `Context`.
-    fn finished(&mut self, ctx: &mut Self::Context) {
-        ctx.stop()
-    }
-}
-
-pub fn foo() {
-    WriteHandler r;
-    r.finished(<|>);
-}
-
-"#,
-    );
-
-    assert_eq!(desc.name, "finished".to_string());
-    assert_eq!(
-        desc.params,
-        vec!["&mut self".to_string(), "ctx".to_string()]
-    );
-    assert_eq!(desc.ret_type, None);
-    assert_eq!(param, Some(1));
-    assert_eq!(
-        desc.doc,
-        Some(
-            r#"Method is called when writer finishes.
-
-By default this method stops actor's `Context`."#
-                .into()
-        )
-    );
-}
-
 fn get_all_refs(text: &str) -> Vec<(FileId, TextRange)> {
     let (analysis, position) = single_file_with_position(text);
     analysis.find_all_refs(position).unwrap()