From 439080f0274cf4def3f393f466ceb05c8cb8bcd2 Mon Sep 17 00:00:00 2001 From: Paulo Lieuthier Date: Tue, 15 Oct 2019 15:29:20 -0300 Subject: assists: add assist for custom implementation for derived trait --- crates/ra_assists/src/assists/add_custom_impl.rs | 189 +++++++++++++++++++++++ 1 file changed, 189 insertions(+) create mode 100644 crates/ra_assists/src/assists/add_custom_impl.rs (limited to 'crates/ra_assists/src/assists') diff --git a/crates/ra_assists/src/assists/add_custom_impl.rs b/crates/ra_assists/src/assists/add_custom_impl.rs new file mode 100644 index 000000000..7e64cd902 --- /dev/null +++ b/crates/ra_assists/src/assists/add_custom_impl.rs @@ -0,0 +1,189 @@ +//! FIXME: write short doc here + +use crate::{Assist, AssistCtx, AssistId}; +use hir::db::HirDatabase; +use join_to_string::join; +use ra_syntax::{ + ast::{self, AstNode}, + Direction, SmolStr, + SyntaxKind::{IDENT, WHITESPACE}, + TextRange, TextUnit, +}; + +const DERIVE_TRAIT: &'static str = "derive"; + +pub(crate) fn add_custom_impl(ctx: AssistCtx) -> Option { + let input = ctx.find_node_at_offset::()?; + let attr = input.syntax().parent().and_then(ast::Attr::cast)?; + + let attr_name = attr + .syntax() + .descendants_with_tokens() + .filter(|t| t.kind() == IDENT) + .find_map(|i| i.into_token()) + .filter(|t| *t.text() == DERIVE_TRAIT)? + .text() + .clone(); + + let trait_token = + ctx.token_at_offset().filter(|t| t.kind() == IDENT && *t.text() != attr_name).next()?; + + let annotated = attr.syntax().siblings(Direction::Next).find_map(|s| ast::Name::cast(s))?; + let annotated_name = annotated.syntax().text().to_string(); + let start_offset = annotated.syntax().parent()?.text_range().end(); + + ctx.add_assist(AssistId("add_custom_impl"), "add custom impl", |edit| { + edit.target(attr.syntax().text_range()); + + let new_attr_input = input + .syntax() + .descendants_with_tokens() + .filter(|t| t.kind() == IDENT) + .filter_map(|t| t.into_token().map(|t| t.text().clone())) + .filter(|t| t != trait_token.text()) + .collect::>(); + let has_more_derives = new_attr_input.len() > 0; + let new_attr_input = + join(new_attr_input.iter()).separator(", ").surround_with("(", ")").to_string(); + let new_attr_input_len = new_attr_input.len(); + + let mut buf = String::new(); + buf.push_str("\n\nimpl "); + buf.push_str(trait_token.text().as_str()); + buf.push_str(" for "); + buf.push_str(annotated_name.as_str()); + buf.push_str(" {\n"); + + let cursor_delta = if has_more_derives { + edit.replace(input.syntax().text_range(), new_attr_input); + input.syntax().text_range().len() - TextUnit::from_usize(new_attr_input_len) + } else { + let attr_range = attr.syntax().text_range(); + edit.delete(attr_range); + + let line_break_range = attr + .syntax() + .next_sibling_or_token() + .filter(|t| t.kind() == WHITESPACE) + .map(|t| t.text_range()) + .unwrap_or(TextRange::from_to(TextUnit::from(0), TextUnit::from(0))); + edit.delete(line_break_range); + + attr_range.len() + line_break_range.len() + }; + + edit.set_cursor(start_offset + TextUnit::of_str(&buf) - cursor_delta); + buf.push_str("\n}"); + edit.insert(start_offset, buf); + }) +} + +#[cfg(test)] +mod tests { + use super::*; + use crate::helpers::{check_assist, check_assist_not_applicable}; + + #[test] + fn add_custom_impl_for_unique_input() { + check_assist( + add_custom_impl, + " +#[derive(Debu<|>g)] +struct Foo { + bar: String, +} + ", + " +struct Foo { + bar: String, +} + +impl Debug for Foo { +<|> +} + ", + ) + } + + #[test] + fn add_custom_impl_for_with_visibility_modifier() { + check_assist( + add_custom_impl, + " +#[derive(Debug<|>)] +pub struct Foo { + bar: String, +} + ", + " +pub struct Foo { + bar: String, +} + +impl Debug for Foo { +<|> +} + ", + ) + } + + #[test] + fn add_custom_impl_when_multiple_inputs() { + check_assist( + add_custom_impl, + " +#[derive(Display, Debug<|>, Serialize)] +struct Foo {} + ", + " +#[derive(Display, Serialize)] +struct Foo {} + +impl Debug for Foo { +<|> +} + ", + ) + } + + #[test] + fn test_ignore_derive_macro_without_input() { + check_assist_not_applicable( + add_custom_impl, + " +#[derive(<|>)] +struct Foo {} + ", + ) + } + + #[test] + fn test_ignore_if_cursor_on_param() { + check_assist_not_applicable( + add_custom_impl, + " +#[derive<|>(Debug)] +struct Foo {} + ", + ); + + check_assist_not_applicable( + add_custom_impl, + " +#[derive(Debug)<|>] +struct Foo {} + ", + ) + } + + #[test] + fn test_ignore_if_not_derive() { + check_assist_not_applicable( + add_custom_impl, + " +#[allow(non_camel_<|>case_types)] +struct Foo {} + ", + ) + } +} -- cgit v1.2.3 From 5b2d52c8df5235fce9d2ae78adc3182a9659b268 Mon Sep 17 00:00:00 2001 From: Paulo Lieuthier Date: Sat, 19 Oct 2019 08:19:06 -0300 Subject: docs: describe new feature 'add custom impl for derived trait' --- crates/ra_assists/src/assists/add_custom_impl.rs | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) (limited to 'crates/ra_assists/src/assists') diff --git a/crates/ra_assists/src/assists/add_custom_impl.rs b/crates/ra_assists/src/assists/add_custom_impl.rs index 7e64cd902..037306fd6 100644 --- a/crates/ra_assists/src/assists/add_custom_impl.rs +++ b/crates/ra_assists/src/assists/add_custom_impl.rs @@ -12,6 +12,23 @@ use ra_syntax::{ const DERIVE_TRAIT: &'static str = "derive"; +// Assist: add_custom_impl +// +// Adds impl block for derived trait. +// +// ``` +// #[derive(Deb<|>ug, Display)] +// struct S; +// ``` +// -> +// ``` +// #[derive(Display)] +// struct S; +// +// impl Debug for S { +// +// } +// ``` pub(crate) fn add_custom_impl(ctx: AssistCtx) -> Option { let input = ctx.find_node_at_offset::()?; let attr = input.syntax().parent().and_then(ast::Attr::cast)?; -- cgit v1.2.3