Merge #1821

1821: Macro completion tweaks r=matklad a=SomeoneToIgnore

Thanks @uHOOCCOOHu for making the macro completion happen :)

I've added a few tweaks to the current completion to make it a bit more convenient:

* Automatically add braces and put the editor cursor inside of them:
<img width="159" alt="image" src="https://user-images.githubusercontent.com/2690773/64737220-022b9f00-d4f5-11e9-8088-76d4678921ab.png">

Currently I have to add the braces manually which is a bit cumbersome.
One further improvement can be to detect if macro accepts no parameters and place the cursor differently for this case.

* Add an exclamation mark to the macro completion label

This helps to distinguish macros from other completion items and also allows to show only macros in completion if you type `!`:
<img width="722" alt="image" src="https://user-images.githubusercontent.com/2690773/64736987-8b8ea180-d4f4-11e9-8355-2ce4f83b7aa8.png">

<img width="732" alt="image" src="https://user-images.githubusercontent.com/2690773/64737214-ffc94500-d4f4-11e9-946e-1ba2db1c7fb1.png">


Additionally, automatic formatting hooks had adjusted two `help.rs` files, I've added them as a last commit to the PR even though they are not really related.

Co-authored-by: Kirill Bulatov <mail4score@gmail.com>

crates/ra_ide_api/src/completion/complete_macro_in_item_position.rs

@@ -37,13 +37,41 @@ mod tests {
             ),
             @r##"[
     CompletionItem {
-        label: "foo",
+        label: "foo!",
         source_range: [46; 46),
         delete: [46; 46),
-        insert: "foo!",
+        insert: "foo!($0)",
         kind: Macro,
         detail: "macro_rules! foo",
     },
+]"##
+        );
+    }
+
+    #[test]
+    fn completes_vec_macros_with_square_brackets() {
+        assert_debug_snapshot!(
+            do_reference_completion(
+                "
+                //- /main.rs
+                macro_rules! vec {
+                    () => {}
+                }
+
+                fn foo() {}
+
+                <|>
+                "
+            ),
+            @r##"[
+    CompletionItem {
+        label: "vec!",
+        source_range: [46; 46),
+        delete: [46; 46),
+        insert: "vec![$0]",
+        kind: Macro,
+        detail: "macro_rules! vec",
+    },
 ]"##
         );
     }

crates/ra_ide_api/src/completion/complete_path.rs

@@ -605,10 +605,10 @@ mod tests {
             ),
             @r###"[
     CompletionItem {
-        label: "foo",
+        label: "foo!",
         source_range: [179; 179),
         delete: [179; 179),
-        insert: "foo!",
+        insert: "foo!($0)",
         kind: Macro,
         detail: "#[macro_export]\nmacro_rules! foo",
     },

crates/ra_ide_api/src/completion/complete_scope.rs

@@ -568,26 +568,26 @@ mod tests {
             ),
             @r##"[
     CompletionItem {
-        label: "bar",
+        label: "bar!",
         source_range: [252; 252),
         delete: [252; 252),
-        insert: "bar!",
+        insert: "bar!($0)",
         kind: Macro,
         detail: "macro_rules! bar",
     },
     CompletionItem {
-        label: "baz",
+        label: "baz!",
         source_range: [252; 252),
         delete: [252; 252),
-        insert: "baz!",
+        insert: "baz!($0)",
         kind: Macro,
         detail: "#[macro_export]\nmacro_rules! baz",
     },
     CompletionItem {
-        label: "foo",
+        label: "foo!",
         source_range: [252; 252),
         delete: [252; 252),
-        insert: "foo!",
+        insert: "foo!($0)",
         kind: Macro,
         detail: "macro_rules! foo",
     },
@@ -633,14 +633,6 @@ mod tests {
                 "
             ),
             @r##"[
-    CompletionItem {
-        label: "foo",
-        source_range: [49; 49),
-        delete: [49; 49),
-        insert: "foo!",
-        kind: Macro,
-        detail: "macro_rules! foo",
-    },
     CompletionItem {
         label: "foo",
         source_range: [49; 49),
@@ -649,6 +641,14 @@ mod tests {
         kind: Function,
         detail: "fn foo()",
     },
+    CompletionItem {
+        label: "foo!",
+        source_range: [49; 49),
+        delete: [49; 49),
+        insert: "foo!($0)",
+        kind: Macro,
+        detail: "macro_rules! foo",
+    },
 ]"##
         );
     }
@@ -670,10 +670,10 @@ mod tests {
             ),
             @r##"[
     CompletionItem {
-        label: "foo",
+        label: "foo!",
         source_range: [57; 57),
         delete: [57; 57),
-        insert: "foo!",
+        insert: "foo!($0)",
         kind: Macro,
         detail: "macro_rules! foo",
     },
@@ -706,10 +706,10 @@ mod tests {
             ),
             @r##"[
     CompletionItem {
-        label: "foo",
+        label: "foo!",
         source_range: [50; 50),
         delete: [50; 50),
-        insert: "foo!",
+        insert: "foo!($0)",
         kind: Macro,
         detail: "macro_rules! foo",
     },

crates/ra_ide_api/src/completion/presentation.rs

@@ -109,12 +109,21 @@ impl Completions {
         if let Some(name) = name {
             let detail = macro_label(&ast_node);
 
-            let builder =
+            let macro_braces_to_insert = match name.as_str() {
-                CompletionItem::new(CompletionKind::Reference, ctx.source_range(), name.clone())
+                "vec" => "[$0]",
-                    .kind(CompletionItemKind::Macro)
+                _ => "($0)",
-                    .set_documentation(macro_.docs(ctx.db))
+            };
-                    .detail(detail)
+            let macro_declaration = name + "!";
-                    .insert_snippet(format!("{}!", name));
+
+            let builder = CompletionItem::new(
+                CompletionKind::Reference,
+                ctx.source_range(),
+                &macro_declaration,
+            )
+            .kind(CompletionItemKind::Macro)
+            .set_documentation(macro_.docs(ctx.db))
+            .detail(detail)
+            .insert_snippet(macro_declaration + macro_braces_to_insert);
 
             self.add(builder);
         }

crates/ra_tools/src/help.rs

@@ -1,45 +1,45 @@
-pub const GLOBAL_HELP: &str = "tasks
+pub const GLOBAL_HELP: &str = "tasks
-
+
-USAGE:
+USAGE:
-    ra_tools <SUBCOMMAND>
+    ra_tools <SUBCOMMAND>
-
+
-FLAGS:
+FLAGS:
-    -h, --help       Prints help information
+    -h, --help       Prints help information
-
+
-SUBCOMMANDS:
+SUBCOMMANDS:
-    format
+    format
-    format-hook
+    format-hook
-    fuzz-tests
+    fuzz-tests
-    gen-syntax
+    gen-syntax
-    gen-tests
+    gen-tests
-    install-ra
+    install-ra
-    lint";
+    lint";
-
+
-pub const INSTALL_RA_HELP: &str = "ra_tools-install-ra
+pub const INSTALL_RA_HELP: &str = "ra_tools-install-ra
-
+
-USAGE:
+USAGE:
-    ra_tools.exe install-ra [FLAGS]
+    ra_tools.exe install-ra [FLAGS]
-
+
-FLAGS:
+FLAGS:
-        --client-code
+        --client-code
-    -h, --help           Prints help information
+    -h, --help           Prints help information
-        --jemalloc
+        --jemalloc
-        --server";
+        --server";
-
+
-pub fn print_no_param_subcommand_help(subcommand: &str) {
+pub fn print_no_param_subcommand_help(subcommand: &str) {
-    eprintln!(
+    eprintln!(
-        "ra_tools-{}
+        "ra_tools-{}
-
+
-USAGE:
+USAGE:
-    ra_tools {}
+    ra_tools {}
-
+
-FLAGS:
+FLAGS:
-    -h, --help       Prints help information",
+    -h, --help       Prints help information",
-        subcommand, subcommand
+        subcommand, subcommand
-    );
+    );
-}
+}
-
+
-pub const INSTALL_RA_CONFLICT: &str =
+pub const INSTALL_RA_CONFLICT: &str =
-    "error: The argument `--server` cannot be used with `--client-code`
+    "error: The argument `--server` cannot be used with `--client-code`
-                    
+                    
-For more information try --help";
+For more information try --help";