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[#1807] Refactor file structure

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Use the more conventional way of importing the ast types, and
put the assist at the top of the file.
This commit is contained in:
Lúcás Meier 2019-10-04 10:51:41 +02:00
parent 1ed1e3d4a7
commit e17243d698
1 changed files with 33 additions and 33 deletions
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66
crates/ra_assists/src/assists/apply_demorgan.rs
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@ -2,42 +2,11 @@
//! This assist transforms boolean expressions of the form `!a || !b` into
//! `!(a && b)`.
use hir::db::HirDatabase;
use ra_syntax::ast::{AstNode, BinExpr, BinOp, Expr, PrefixOp};
use ra_syntax::ast::{self, AstNode};
use ra_syntax::SyntaxNode;
use crate::{Assist, AssistCtx, AssistId};
// Return the opposite text for a given logical operator, if it makes sense
fn opposite_logic_op(kind: BinOp) -> Option<&'static str> {
match kind {
BinOp::BooleanOr => Some("&&"),
BinOp::BooleanAnd => Some("||"),
_ => None,
}
}
// This function tries to undo unary negation, or inequality
fn undo_negation(node: SyntaxNode) -> Option<String> {
match Expr::cast(node)? {
Expr::BinExpr(bin) => match bin.op_kind()? {
BinOp::NegatedEqualityTest => {
let lhs = bin.lhs()?.syntax().text();
let rhs = bin.rhs()?.syntax().text();
Some(format!("{} == {}", lhs, rhs))
}
_ => None,
},
Expr::PrefixExpr(pe) => match pe.op_kind()? {
PrefixOp::Not => {
let child = pe.expr()?.syntax().text();
Some(String::from(child))
}
_ => None,
},
_ => None,
}
}
/// Assist for applying demorgan's law
///
/// This transforms expressions of the form `!l || !r` into `!(l && r)`.
@ -45,7 +14,7 @@ fn undo_negation(node: SyntaxNode) -> Option<String> {
/// on either `||` or `&&`, with both operands being a negation of some kind.
/// This means something of the form `!x` or `x != y`.
pub(crate) fn apply_demorgan(mut ctx: AssistCtx<impl HirDatabase>) -> Option<Assist> {
let expr = ctx.node_at_offset::<BinExpr>()?;
let expr = ctx.node_at_offset::<ast::BinExpr>()?;
let op = expr.op_kind()?;
let op_range = expr.op_token()?.text_range();
let opposite_op = opposite_logic_op(op)?;
@ -69,6 +38,37 @@ pub(crate) fn apply_demorgan(mut ctx: AssistCtx<impl HirDatabase>) -> Option<Ass
ctx.build()
}
// Return the opposite text for a given logical operator, if it makes sense
fn opposite_logic_op(kind: ast::BinOp) -> Option<&'static str> {
match kind {
ast::BinOp::BooleanOr => Some("&&"),
ast::BinOp::BooleanAnd => Some("||"),
_ => None,
}
}
// This function tries to undo unary negation, or inequality
fn undo_negation(node: SyntaxNode) -> Option<String> {
match ast::Expr::cast(node)? {
ast::Expr::BinExpr(bin) => match bin.op_kind()? {
ast::BinOp::NegatedEqualityTest => {
let lhs = bin.lhs()?.syntax().text();
let rhs = bin.rhs()?.syntax().text();
Some(format!("{} == {}", lhs, rhs))
}
_ => None,
},
ast::Expr::PrefixExpr(pe) => match pe.op_kind()? {
ast::PrefixOp::Not => {
let child = pe.expr()?.syntax().text();
Some(String::from(child))
}
_ => None,
},
_ => None,
}
}
#[cfg(test)]
mod tests {
use super::*;