2 files changed, 98 insertions, 21 deletions

diff --git a/crates/ra_ide/src/inlay_hints.rs b/crates/ra_ide/src/inlay_hints.rs
index cf0cbdbd0..59922e14c 100644
--- a/crates/ra_ide/src/inlay_hints.rs
+++ b/crates/ra_ide/src/inlay_hints.rs
@@ -10,7 +10,20 @@ use ra_syntax::{
 
 use crate::{FileId, FunctionSignature};
 
-#[derive(Debug, PartialEq, Eq)]
+#[derive(Clone, Debug, PartialEq, Eq)]
+pub struct InlayConfig {
+    pub type_hints: bool,
+    pub parameter_hints: bool,
+    pub max_length: Option<usize>,
+}
+
+impl Default for InlayConfig {
+    fn default() -> Self {
+        Self { type_hints: true, parameter_hints: true, max_length: None }
+    }
+}
+
+#[derive(Clone, Debug, PartialEq, Eq)]
 pub enum InlayKind {
     TypeHint,
     ParameterHint,
@@ -26,7 +39,7 @@ pub struct InlayHint {
 pub(crate) fn inlay_hints(
     db: &RootDatabase,
     file_id: FileId,
-    max_inlay_hint_length: Option<usize>,
+    inlay_hint_opts: &InlayConfig,
 ) -> Vec<InlayHint> {
     let _p = profile("inlay_hints");
     let sema = Semantics::new(db);
@@ -36,9 +49,9 @@ pub(crate) fn inlay_hints(
     for node in file.syntax().descendants() {
         match_ast! {
             match node {
-                ast::CallExpr(it) => { get_param_name_hints(&mut res, &sema, ast::Expr::from(it)); },
-                ast::MethodCallExpr(it) => { get_param_name_hints(&mut res, &sema, ast::Expr::from(it)); },
-                ast::BindPat(it) => { get_bind_pat_hints(&mut res, &sema, max_inlay_hint_length, it); },
+                ast::CallExpr(it) => { get_param_name_hints(&mut res, &sema, inlay_hint_opts, ast::Expr::from(it)); },
+                ast::MethodCallExpr(it) => { get_param_name_hints(&mut res, &sema, inlay_hint_opts, ast::Expr::from(it)); },
+                ast::BindPat(it) => { get_bind_pat_hints(&mut res, &sema, inlay_hint_opts, it); },
                 _ => (),
             }
         }
@@ -49,8 +62,13 @@ pub(crate) fn inlay_hints(
 fn get_param_name_hints(
     acc: &mut Vec<InlayHint>,
     sema: &Semantics<RootDatabase>,
+    inlay_hint_opts: &InlayConfig,
     expr: ast::Expr,
 ) -> Option<()> {
+    if !inlay_hint_opts.parameter_hints {
+        return None;
+    }
+
     let args = match &expr {
         ast::Expr::CallExpr(expr) => expr.arg_list()?.args(),
         ast::Expr::MethodCallExpr(expr) => expr.arg_list()?.args(),
@@ -84,9 +102,13 @@ fn get_param_name_hints(
 fn get_bind_pat_hints(
     acc: &mut Vec<InlayHint>,
     sema: &Semantics<RootDatabase>,
-    max_inlay_hint_length: Option<usize>,
+    inlay_hint_opts: &InlayConfig,
     pat: ast::BindPat,
 ) -> Option<()> {
+    if !inlay_hint_opts.type_hints {
+        return None;
+    }
+
     let ty = sema.type_of_pat(&pat.clone().into())?;
 
     if should_not_display_type_hint(sema.db, &pat, &ty) {
@@ -96,7 +118,7 @@ fn get_bind_pat_hints(
     acc.push(InlayHint {
         range: pat.syntax().text_range(),
         kind: InlayKind::TypeHint,
-        label: ty.display_truncated(sema.db, max_inlay_hint_length).to_string().into(),
+        label: ty.display_truncated(sema.db, inlay_hint_opts.max_length).to_string().into(),
     });
     Some(())
 }
@@ -202,11 +224,66 @@ fn get_fn_signature(sema: &Semantics<RootDatabase>, expr: &ast::Expr) -> Option<
 
 #[cfg(test)]
 mod tests {
+    use crate::inlay_hints::InlayConfig;
     use insta::assert_debug_snapshot;
 
     use crate::mock_analysis::single_file;
 
     #[test]
+    fn param_hints_only() {
+        let (analysis, file_id) = single_file(
+            r#"
+            fn foo(a: i32, b: i32) -> i32 { a + b }
+            fn main() {
+                let _x = foo(4, 4);
+            }"#,
+        );
+        assert_debug_snapshot!(analysis.inlay_hints(file_id, &InlayConfig{ parameter_hints: true, type_hints: false, max_length: None}).unwrap(), @r###"
+        [
+            InlayHint {
+                range: [106; 107),
+                kind: ParameterHint,
+                label: "a",
+            },
+            InlayHint {
+                range: [109; 110),
+                kind: ParameterHint,
+                label: "b",
+            },
+        ]"###);
+    }
+
+    #[test]
+    fn hints_disabled() {
+        let (analysis, file_id) = single_file(
+            r#"
+            fn foo(a: i32, b: i32) -> i32 { a + b }
+            fn main() {
+                let _x = foo(4, 4);
+            }"#,
+        );
+        assert_debug_snapshot!(analysis.inlay_hints(file_id, &InlayConfig{ type_hints: false, parameter_hints: false, max_length: None}).unwrap(), @r###"[]"###);
+    }
+
+    #[test]
+    fn type_hints_only() {
+        let (analysis, file_id) = single_file(
+            r#"
+            fn foo(a: i32, b: i32) -> i32 { a + b }
+            fn main() {
+                let _x = foo(4, 4);
+            }"#,
+        );
+        assert_debug_snapshot!(analysis.inlay_hints(file_id, &InlayConfig{ type_hints: true, parameter_hints: false, max_length: None}).unwrap(), @r###"
+        [
+            InlayHint {
+                range: [97; 99),
+                kind: TypeHint,
+                label: "i32",
+            },
+        ]"###);
+    }
+    #[test]
     fn default_generic_types_should_not_be_displayed() {
         let (analysis, file_id) = single_file(
             r#"
@@ -221,7 +298,7 @@ fn main() {
 }"#,
         );
 
-        assert_debug_snapshot!(analysis.inlay_hints(file_id, None).unwrap(), @r###"
+        assert_debug_snapshot!(analysis.inlay_hints(file_id, &InlayConfig::default()).unwrap(), @r###"
         [
             InlayHint {
                 range: [69; 71),
@@ -278,7 +355,7 @@ fn main() {
 }"#,
         );
 
-        assert_debug_snapshot!(analysis.inlay_hints(file_id, None).unwrap(), @r###"
+        assert_debug_snapshot!(analysis.inlay_hints(file_id, &InlayConfig::default()).unwrap(), @r###"
         [
             InlayHint {
                 range: [193; 197),
@@ -358,7 +435,7 @@ fn main() {
 }"#,
         );
 
-        assert_debug_snapshot!(analysis.inlay_hints(file_id, None).unwrap(), @r###"
+        assert_debug_snapshot!(analysis.inlay_hints(file_id, &InlayConfig::default()).unwrap(), @r###"
         [
             InlayHint {
                 range: [21; 30),
@@ -422,7 +499,7 @@ fn main() {
 }"#,
         );
 
-        assert_debug_snapshot!(analysis.inlay_hints(file_id, None).unwrap(), @r###"
+        assert_debug_snapshot!(analysis.inlay_hints(file_id, &InlayConfig::default()).unwrap(), @r###"
         [
             InlayHint {
                 range: [21; 30),
@@ -472,7 +549,7 @@ fn main() {
 }"#,
         );
 
-        assert_debug_snapshot!(analysis.inlay_hints(file_id, None).unwrap(), @r###"
+        assert_debug_snapshot!(analysis.inlay_hints(file_id, &InlayConfig::default()).unwrap(), @r###"
         [
             InlayHint {
                 range: [188; 192),
@@ -567,7 +644,7 @@ fn main() {
 }"#,
         );
 
-        assert_debug_snapshot!(analysis.inlay_hints(file_id, None).unwrap(), @r###"
+        assert_debug_snapshot!(analysis.inlay_hints(file_id, &InlayConfig::default()).unwrap(), @r###"
         [
             InlayHint {
                 range: [188; 192),
@@ -662,7 +739,7 @@ fn main() {
 }"#,
         );
 
-        assert_debug_snapshot!(analysis.inlay_hints(file_id, None).unwrap(), @r###"
+        assert_debug_snapshot!(analysis.inlay_hints(file_id, &InlayConfig::default()).unwrap(), @r###"
         [
             InlayHint {
                 range: [252; 256),
@@ -734,7 +811,7 @@ fn main() {
 }"#,
         );
 
-        assert_debug_snapshot!(analysis.inlay_hints(file_id, Some(8)).unwrap(), @r###"
+        assert_debug_snapshot!(analysis.inlay_hints(file_id, &InlayConfig { max_length: Some(8), ..Default::default() }).unwrap(), @r###"
         [
             InlayHint {
                 range: [74; 75),
@@ -822,7 +899,7 @@ fn main() {
 }"#,
         );
 
-        assert_debug_snapshot!(analysis.inlay_hints(file_id, None).unwrap(), @r###"
+        assert_debug_snapshot!(analysis.inlay_hints(file_id, &InlayConfig::default()).unwrap(), @r###"
         [
             InlayHint {
                 range: [798; 809),
@@ -944,7 +1021,7 @@ fn main() {
 }"#,
         );
 
-        assert_debug_snapshot!(analysis.inlay_hints(file_id, Some(8)).unwrap(), @r###"
+        assert_debug_snapshot!(analysis.inlay_hints(file_id, &InlayConfig { max_length: Some(8), ..Default::default() }).unwrap(), @r###"
         []
         "###
         );
@@ -970,7 +1047,7 @@ fn main() {
 }"#,
         );
 
-        assert_debug_snapshot!(analysis.inlay_hints(file_id, Some(8)).unwrap(), @r###"
+        assert_debug_snapshot!(analysis.inlay_hints(file_id, &InlayConfig { max_length: Some(8), ..Default::default() }).unwrap(), @r###"
         []
         "###
         );
diff --git a/crates/ra_ide/src/lib.rs b/crates/ra_ide/src/lib.rs
index 015fae195..922e4caa8 100644
--- a/crates/ra_ide/src/lib.rs
+++ b/crates/ra_ide/src/lib.rs
@@ -68,7 +68,7 @@ pub use crate::{
     expand_macro::ExpandedMacro,
     folding_ranges::{Fold, FoldKind},
     hover::HoverResult,
-    inlay_hints::{InlayHint, InlayKind},
+    inlay_hints::{InlayConfig, InlayHint, InlayKind},
     references::{Declaration, Reference, ReferenceAccess, ReferenceKind, ReferenceSearchResult},
     runnables::{Runnable, RunnableKind, TestId},
     source_change::{FileSystemEdit, SourceChange, SourceFileEdit},
@@ -319,9 +319,9 @@ impl Analysis {
     pub fn inlay_hints(
         &self,
         file_id: FileId,
-        max_inlay_hint_length: Option<usize>,
+        inlay_hint_opts: &InlayConfig,
     ) -> Cancelable<Vec<InlayHint>> {
-        self.with_db(|db| inlay_hints::inlay_hints(db, file_id, max_inlay_hint_length))
+        self.with_db(|db| inlay_hints::inlay_hints(db, file_id, inlay_hint_opts))
     }
 
     /// Returns the set of folding ranges.