Introduce assists utils

Author: matklad

crates/ra_assists/src/handlers/apply_demorgan.rs

@@ -1,7 +1,6 @@
-use super::invert_if::invert_boolean_expression;
 use ra_syntax::ast::{self, AstNode};
 
-use crate::{Assist, AssistCtx, AssistId};
+use crate::{utils::invert_boolean_expression, Assist, AssistCtx, AssistId};
 
 // Assist: apply_demorgan
 //

crates/ra_assists/src/handlers/early_return.rs

@@ -10,7 +10,7 @@ use ra_syntax::{
 
 use crate::{
     assist_ctx::{Assist, AssistCtx},
-    handlers::invert_if::invert_boolean_expression,
+    utils::invert_boolean_expression,
     AssistId,
 };
 

crates/ra_assists/src/handlers/invert_if.rs

@@ -1,7 +1,7 @@
-use ra_syntax::ast::{self, make, AstNode};
+use ra_syntax::ast::{self, AstNode};
 use ra_syntax::T;
 
-use crate::{Assist, AssistCtx, AssistId};
+use crate::{utils::invert_boolean_expression, Assist, AssistCtx, AssistId};
 
 // Assist: invert_if
 //
@@ -51,27 +51,6 @@ pub(crate) fn invert_if(ctx: AssistCtx) -> Option<Assist> {
     None
 }
 
-pub(crate) fn invert_boolean_expression(expr: ast::Expr) -> ast::Expr {
-    if let Some(expr) = invert_special_case(&expr) {
-        return expr;
-    }
-    make::expr_prefix(T![!], expr)
-}
-
-pub(crate) fn invert_special_case(expr: &ast::Expr) -> Option<ast::Expr> {
-    match expr {
-        ast::Expr::BinExpr(bin) => match bin.op_kind()? {
-            ast::BinOp::NegatedEqualityTest => bin.replace_op(T![==]).map(|it| it.into()),
-            ast::BinOp::EqualityTest => bin.replace_op(T![!=]).map(|it| it.into()),
-            _ => None,
-        },
-        ast::Expr::PrefixExpr(pe) if pe.op_kind()? == ast::PrefixOp::Not => pe.expr(),
-        // FIXME:
-        // ast::Expr::Literal(true | false )
-        _ => None,
-    }
-}
-
 #[cfg(test)]
 mod tests {
     use super::*;

crates/ra_assists/src/lib.rs

@@ -9,6 +9,7 @@ mod assist_ctx;
 mod marks;
 #[cfg(test)]
 mod doc_tests;
+mod utils;
 pub mod ast_transform;
 
 use std::cmp::Ordering;

crates/ra_assists/src/utils.rs

@@ -0,0 +1,27 @@
+//! Assorted functions shared by several assists.
+
+use ra_syntax::{
+    ast::{self, make},
+    T,
+};
+
+pub(crate) fn invert_boolean_expression(expr: ast::Expr) -> ast::Expr {
+    if let Some(expr) = invert_special_case(&expr) {
+        return expr;
+    }
+    make::expr_prefix(T![!], expr)
+}
+
+fn invert_special_case(expr: &ast::Expr) -> Option<ast::Expr> {
+    match expr {
+        ast::Expr::BinExpr(bin) => match bin.op_kind()? {
+            ast::BinOp::NegatedEqualityTest => bin.replace_op(T![==]).map(|it| it.into()),
+            ast::BinOp::EqualityTest => bin.replace_op(T![!=]).map(|it| it.into()),
+            _ => None,
+        },
+        ast::Expr::PrefixExpr(pe) if pe.op_kind()? == ast::PrefixOp::Not => pe.expr(),
+        // FIXME:
+        // ast::Expr::Literal(true | false )
+        _ => None,
+    }
+}