Fix clippy::manual_let_else (pedantic) (#939)

src/flake8_comprehensions/fixes.rs

@@ -39,9 +39,7 @@ pub fn fix_unnecessary_generator_list(
     let call = match_call(body)?;
     let arg = match_arg(call)?;
 
-    let generator_exp = if let Expression::GeneratorExp(generator_exp) = &arg.value {
-        generator_exp
-    } else {
+    let Expression::GeneratorExp(generator_exp) = &arg.value else {
         return Err(anyhow::anyhow!(
             "Expected node to be: Expression::GeneratorExp"
         ));
@@ -82,9 +80,7 @@ pub fn fix_unnecessary_generator_set(
     let call = match_call(body)?;
     let arg = match_arg(call)?;
 
-    let generator_exp = if let Expression::GeneratorExp(generator_exp) = &arg.value {
-        generator_exp
-    } else {
+    let Expression::GeneratorExp(generator_exp) = &arg.value else {
         return Err(anyhow::anyhow!(
             "Expected node to be: Expression::GeneratorExp"
         ));
@@ -126,28 +122,20 @@ pub fn fix_unnecessary_generator_dict(
     let arg = match_arg(call)?;
 
     // Extract the (k, v) from `(k, v) for ...`.
-    let generator_exp = if let Expression::GeneratorExp(generator_exp) = &arg.value {
-        generator_exp
-    } else {
+    let Expression::GeneratorExp(generator_exp) = &arg.value else {
         return Err(anyhow::anyhow!(
             "Expected node to be: Expression::GeneratorExp"
         ));
     };
-    let tuple = if let Expression::Tuple(tuple) = &generator_exp.elt.as_ref() {
-        tuple
-    } else {
+    let Expression::Tuple(tuple) = &generator_exp.elt.as_ref() else {
         return Err(anyhow::anyhow!("Expected node to be: Expression::Tuple"));
     };
-    let key = if let Some(Element::Simple { value, .. }) = &tuple.elements.get(0) {
-        value
-    } else {
+    let Some(Element::Simple { value: key, .. }) = &tuple.elements.get(0) else {
         return Err(anyhow::anyhow!(
             "Expected tuple to contain a key as the first element"
         ));
     };
-    let value = if let Some(Element::Simple { value, .. }) = &tuple.elements.get(1) {
-        value
-    } else {
+    let Some(Element::Simple { value, .. }) = &tuple.elements.get(1) else {
         return Err(anyhow::anyhow!(
             "Expected tuple to contain a key as the second element"
         ));
@@ -192,9 +180,7 @@ pub fn fix_unnecessary_list_comprehension_set(
     let call = match_call(body)?;
     let arg = match_arg(call)?;
 
-    let list_comp = if let Expression::ListComp(list_comp) = &arg.value {
-        list_comp
-    } else {
+    let Expression::ListComp(list_comp) = &arg.value else {
         return Err(anyhow::anyhow!("Expected node to be: Expression::ListComp"));
     };
 
@@ -233,25 +219,18 @@ pub fn fix_unnecessary_list_comprehension_dict(
     let call = match_call(body)?;
     let arg = match_arg(call)?;
 
-    let list_comp = if let Expression::ListComp(list_comp) = &arg.value {
-        list_comp
-    } else {
+    let Expression::ListComp(list_comp) = &arg.value else {
         return Err(anyhow::anyhow!("Expected node to be: Expression::ListComp"));
     };
 
-    let tuple = if let Expression::Tuple(tuple) = &*list_comp.elt {
-        tuple
-    } else {
+    let Expression::Tuple(tuple) = &*list_comp.elt else {
         return Err(anyhow::anyhow!("Expected node to be: Expression::Tuple"));
     };
 
-    let (key, comma, value) = match &tuple.elements[..] {
-        [Element::Simple {
+    let [Element::Simple {
             value: key,
             comma: Some(comma),
-        }, Element::Simple { value, .. }] => (key, comma, value),
-        _ => return Err(anyhow::anyhow!("Expected tuple with two elements")),
-    };
+        }, Element::Simple { value, .. }] = &tuple.elements[..] else { return Err(anyhow::anyhow!("Expected tuple with two elements")) };
 
     body.value = Expression::DictComp(Box::new(DictComp {
         key: Box::new(key.clone()),
@@ -409,9 +388,7 @@ pub fn fix_unnecessary_collection_call(
     let mut tree = match_module(&module_text)?;
     let mut body = match_expr(&mut tree)?;
     let call = match_call(body)?;
-    let name = if let Expression::Name(name) = &call.func.as_ref() {
-        name
-    } else {
+    let Expression::Name(name) = &call.func.as_ref() else {
         return Err(anyhow::anyhow!("Expected node to be: Expression::Name"));
     };
 

src/pyflakes/fixes.rs

@@ -22,14 +22,10 @@ pub fn remove_unused_imports(
     let module_text = locator.slice_source_code_range(&Range::from_located(stmt));
     let mut tree = match_module(&module_text)?;
 
-    let body = if let Some(Statement::Simple(body)) = tree.body.first_mut() {
-        body
-    } else {
+    let Some(Statement::Simple(body)) = tree.body.first_mut() else {
         return Err(anyhow::anyhow!("Expected node to be: Statement::Simple"));
     };
-    let body = if let Some(SmallStatement::Import(body)) = body.body.first_mut() {
-        body
-    } else {
+    let Some(SmallStatement::Import(body)) = body.body.first_mut() else {
         return Err(anyhow::anyhow!(
             "Expected node to be: SmallStatement::ImportFrom"
         ));
@@ -80,22 +76,16 @@ pub fn remove_unused_import_froms(
     let module_text = locator.slice_source_code_range(&Range::from_located(stmt));
     let mut tree = match_module(&module_text)?;
 
-    let body = if let Some(Statement::Simple(body)) = tree.body.first_mut() {
-        body
-    } else {
+    let Some(Statement::Simple(body)) = tree.body.first_mut() else {
         return Err(anyhow::anyhow!("Expected node to be: Statement::Simple"));
     };
-    let body = if let Some(SmallStatement::ImportFrom(body)) = body.body.first_mut() {
-        body
-    } else {
+    let Some(SmallStatement::ImportFrom(body)) = body.body.first_mut() else {
         return Err(anyhow::anyhow!(
             "Expected node to be: SmallStatement::ImportFrom"
         ));
     };
 
-    let aliases = if let ImportNames::Aliases(aliases) = &mut body.names {
-        aliases
-    } else {
+    let ImportNames::Aliases(aliases) = &mut body.names else {
         return Err(anyhow::anyhow!("Expected node to be: Aliases"));
     };
 

src/pyupgrade/fixes.rs

@@ -111,10 +111,7 @@ pub fn remove_super_arguments(locator: &SourceCodeLocator, expr: &Expr) -> Optio
     let range = Range::from_located(expr);
     let contents = locator.slice_source_code_range(&range);
 
-    let mut tree = match libcst_native::parse_module(&contents, None) {
-        Ok(m) => m,
-        Err(_) => return None,
-    };
+    let mut tree = libcst_native::parse_module(&contents, None).ok()?;
 
     if let Some(Statement::Simple(body)) = tree.body.first_mut() {
         if let Some(SmallStatement::Expr(body)) = body.body.first_mut() {
@@ -150,22 +147,16 @@ pub fn remove_unnecessary_future_import(
     let module_text = locator.slice_source_code_range(&Range::from_located(stmt));
     let mut tree = match_module(&module_text)?;
 
-    let body = if let Some(Statement::Simple(body)) = tree.body.first_mut() {
-        body
-    } else {
+    let Some(Statement::Simple(body)) = tree.body.first_mut() else {
         return Err(anyhow::anyhow!("Expected node to be: Statement::Simple"));
     };
-    let body = if let Some(SmallStatement::ImportFrom(body)) = body.body.first_mut() {
-        body
-    } else {
+    let Some(SmallStatement::ImportFrom(body)) = body.body.first_mut() else {
         return Err(anyhow::anyhow!(
             "Expected node to be: SmallStatement::ImportFrom"
         ));
     };
 
-    let aliases = if let ImportNames::Aliases(aliases) = &mut body.names {
-        aliases
-    } else {
+    let ImportNames::Aliases(aliases) = &mut body.names else {
         return Err(anyhow::anyhow!("Expected node to be: Aliases"));
     };