Avoid generating empty statement bodies (#700)

resources/test/fixtures/F401_0.py

@@ -28,7 +28,6 @@ from blah import ClassA, ClassB, ClassC
 if TYPE_CHECKING:
     from models import Fruit, Nut, Vegetable
 
-
 if TYPE_CHECKING:
     import shelve
     import importlib

resources/test/fixtures/U010.py

@@ -7,6 +7,7 @@ from __future__ import invalid_module, generators
 
 if True:
     from __future__ import generator_stop
+    from __future__ import generators
 
 if True:
     from __future__ import generator_stop

src/check_ast.rs

@@ -2411,16 +2411,20 @@ impl<'a> Checker<'a> {
                             .iter()
                             .map(|index| self.parents[*index])
                             .collect();
-
+                        match match kind {
-                        let removal_fn = match kind {
                             ImportKind::Import => pyflakes::fixes::remove_unused_imports,
                             ImportKind::ImportFrom => pyflakes::fixes::remove_unused_import_froms,
-                        };
+                        }(
-
+                            self.locator, &full_names, child, parent, &deleted
-                        match removal_fn(self.locator, &full_names, child, parent, &deleted) {
+                        ) {
-                            Ok(fix) => Some(fix),
+                            Ok(fix) => {
+                                if fix.patch.content.is_empty() || fix.patch.content == "pass" {
+                                    self.deletions.insert(defined_by);
+                                }
+                                Some(fix)
+                            }
                             Err(e) => {
-                                error!("Failed to fix unused imports: {}", e);
+                                error!("Failed to remove unused imports: {}", e);
                                 None
                             }
                         }

src/flake8_print/plugins/print_call.rs

@@ -7,6 +7,7 @@ use crate::check_ast::Checker;
 use crate::checks::CheckCode;
 use crate::flake8_print::checks;
 
+/// T201, T203
 pub fn print_call(checker: &mut Checker, expr: &Expr, func: &Expr) {
     if let Some(mut check) = checks::print_call(
         expr,
@@ -26,7 +27,6 @@ pub fn print_call(checker: &mut Checker, expr: &Expr, func: &Expr) {
                     .iter()
                     .map(|index| checker.parents[*index])
                     .collect();
-
                 match helpers::remove_stmt(
                     checker.parents[context.defined_by],
                     context.defined_in.map(|index| checker.parents[index]),
@@ -38,7 +38,7 @@ pub fn print_call(checker: &mut Checker, expr: &Expr, func: &Expr) {
                         }
                         check.amend(fix)
                     }
-                    Err(e) => error!("Failed to fix unused imports: {}", e),
+                    Err(e) => error!("Failed to remove print call: {}", e),
                 }
             }
         }

src/pyupgrade/plugins/deprecated_unittest_alias.rs

@@ -28,6 +28,7 @@ static DEPRECATED_ALIASES: Lazy<BTreeMap<&'static str, &'static str>> = Lazy::ne
     ])
 });
 
+/// U005
 pub fn deprecated_unittest_alias(checker: &mut Checker, expr: &Expr) {
     if let ExprKind::Attribute { value, attr, .. } = &expr.node {
         if let Some(target) = DEPRECATED_ALIASES.get(attr.as_str()) {

src/pyupgrade/plugins/super_call_with_parameters.rs

@@ -5,6 +5,7 @@ use crate::check_ast::Checker;
 use crate::pyupgrade;
 use crate::pyupgrade::checks;
 
+/// U008
 pub fn super_call_with_parameters(checker: &mut Checker, expr: &Expr, func: &Expr, args: &[Expr]) {
     // Only bother going through the super check at all if we're in a `super` call.
     // (We check this in `check_super_args` too, so this is just an optimization.)

src/pyupgrade/plugins/type_of_primitive.rs

@@ -6,6 +6,7 @@ use crate::check_ast::Checker;
 use crate::checks::CheckKind;
 use crate::pyupgrade::checks;
 
+/// U003
 pub fn type_of_primitive(checker: &mut Checker, expr: &Expr, func: &Expr, args: &[Expr]) {
     if let Some(mut check) = checks::type_of_primitive(func, args, Range::from_located(expr)) {
         if checker.patch() {

src/pyupgrade/plugins/unnecessary_abspath.rs

@@ -5,6 +5,7 @@ use crate::autofix::Fix;
 use crate::check_ast::Checker;
 use crate::pyupgrade::checks;
 
+/// U002
 pub fn unnecessary_abspath(checker: &mut Checker, expr: &Expr, func: &Expr, args: &[Expr]) {
     if let Some(mut check) = checks::unnecessary_abspath(func, args, Range::from_located(expr)) {
         if checker.patch() {

src/pyupgrade/plugins/unnecessary_future_import.rs

@@ -1,5 +1,6 @@
 use std::collections::BTreeSet;
 
+use log::error;
 use rustpython_ast::{AliasData, Located};
 use rustpython_parser::ast::Stmt;
 
@@ -62,14 +63,20 @@ pub fn unnecessary_future_import(checker: &mut Checker, stmt: &Stmt, names: &[Lo
                 .iter()
                 .map(|index| checker.parents[*index])
                 .collect();
-            if let Ok(fix) = fixes::remove_unnecessary_future_import(
+            match fixes::remove_unnecessary_future_import(
                 checker.locator,
                 &removable_index,
                 checker.parents[context.defined_by],
                 context.defined_in.map(|index| checker.parents[index]),
                 &deleted,
             ) {
-                check.amend(fix);
+                Ok(fix) => {
+                    if fix.patch.content.is_empty() || fix.patch.content == "pass" {
+                        checker.deletions.insert(context.defined_by);
+                    }
+                    check.amend(fix);
+                }
+                Err(e) => error!("Failed to remove __future__ import: {}", e),
             }
         }
         checker.add_check(check);

src/pyupgrade/plugins/unnecessary_lru_cache_params.rs

@@ -3,6 +3,7 @@ use rustpython_parser::ast::Expr;
 use crate::check_ast::Checker;
 use crate::pyupgrade::{checks, fixes};
 
+/// U011
 pub fn unnecessary_lru_cache_params(checker: &mut Checker, decorator_list: &[Expr]) {
     if let Some(mut check) = checks::unnecessary_lru_cache_params(
         decorator_list,

src/pyupgrade/plugins/use_pep585_annotation.rs

@@ -5,6 +5,7 @@ use crate::autofix::Fix;
 use crate::check_ast::Checker;
 use crate::checks::{Check, CheckKind};
 
+/// U006
 pub fn use_pep585_annotation(checker: &mut Checker, expr: &Expr, id: &str) {
     let mut check = Check::new(
         CheckKind::UsePEP585Annotation(id.to_string()),

src/pyupgrade/plugins/use_pep604_annotation.rs

@@ -41,6 +41,7 @@ fn union(elts: &[Expr]) -> Expr {
     }
 }
 
+/// U007
 pub fn use_pep604_annotation(checker: &mut Checker, expr: &Expr, value: &Expr, slice: &Expr) {
     if checker.match_typing_module(value, "Optional") {
         let mut check = Check::new(CheckKind::UsePEP604Annotation, Range::from_located(expr));

src/pyupgrade/plugins/useless_metaclass_type.rs

@@ -6,6 +6,7 @@ use crate::autofix::helpers;
 use crate::check_ast::Checker;
 use crate::pyupgrade::checks;
 
+/// U001
 pub fn useless_metaclass_type(checker: &mut Checker, stmt: &Stmt, value: &Expr, targets: &[Expr]) {
     if let Some(mut check) =
         checks::useless_metaclass_type(targets, value, Range::from_located(stmt))
@@ -29,7 +30,7 @@ pub fn useless_metaclass_type(checker: &mut Checker, stmt: &Stmt, value: &Expr,
                     }
                     check.amend(fix)
                 }
-                Err(e) => error!("Failed to fix unused imports: {}", e),
+                Err(e) => error!("Failed to fix remove metaclass type: {}", e),
             }
         }
         checker.add_check(check);

src/pyupgrade/plugins/useless_object_inheritance.rs

@@ -4,6 +4,7 @@ use crate::check_ast::Checker;
 use crate::pyupgrade;
 use crate::pyupgrade::checks;
 
+/// U004
 pub fn useless_object_inheritance(
     checker: &mut Checker,
     stmt: &Stmt,

src/snapshots/ruff__linter__tests__F401_F401_0.py.snap

@@ -67,19 +67,19 @@ expression: checks
       - - shelve
       - false
   location:
-    row: 33
+    row: 32
     column: 4
   end_location:
-    row: 33
+    row: 32
     column: 17
   fix:
     patch:
       content: ""
       location:
-        row: 33
+        row: 32
         column: 0
       end_location:
-        row: 34
+        row: 33
         column: 0
     applied: false
 - kind:
@@ -87,39 +87,39 @@ expression: checks
       - - importlib
       - false
   location:
-    row: 34
+    row: 33
     column: 4
   end_location:
-    row: 34
+    row: 33
     column: 20
   fix:
     patch:
-      content: ""
+      content: pass
       location:
-        row: 34
+        row: 33
-        column: 0
+        column: 4
       end_location:
-        row: 35
+        row: 33
-        column: 0
+        column: 20
     applied: false
 - kind:
     UnusedImport:
       - - pathlib
       - false
   location:
-    row: 38
+    row: 37
     column: 4
   end_location:
-    row: 38
+    row: 37
     column: 18
   fix:
     patch:
       content: ""
       location:
-        row: 38
+        row: 37
         column: 0
       end_location:
-        row: 39
+        row: 38
         column: 0
     applied: false
 - kind:
@@ -127,19 +127,19 @@ expression: checks
       - - pickle
       - false
   location:
-    row: 53
+    row: 52
     column: 8
   end_location:
-    row: 53
+    row: 52
     column: 21
   fix:
     patch:
       content: pass
       location:
-        row: 53
+        row: 52
         column: 8
       end_location:
-        row: 53
+        row: 52
         column: 21
     applied: false
 

src/snapshots/ruff__linter__tests__U010_U010.py.snap

@@ -129,52 +129,71 @@ expression: checks
   end_location:
     row: 9
     column: 41
-  fix:
-    patch:
-      content: pass
-      location:
-        row: 9
-        column: 4
-      end_location:
-        row: 9
-        column: 41
-    applied: false
-- kind:
-    UnnecessaryFutureImport:
-      - generator_stop
-  location:
-    row: 12
-    column: 4
-  end_location:
-    row: 12
-    column: 41
   fix:
     patch:
       content: ""
       location:
-        row: 12
+        row: 9
         column: 0
       end_location:
-        row: 13
+        row: 10
         column: 0
     applied: false
 - kind:
     UnnecessaryFutureImport:
       - generators
+  location:
+    row: 10
+    column: 4
+  end_location:
+    row: 10
+    column: 37
+  fix:
+    patch:
+      content: pass
+      location:
+        row: 10
+        column: 4
+      end_location:
+        row: 10
+        column: 37
+    applied: false
+- kind:
+    UnnecessaryFutureImport:
+      - generator_stop
   location:
     row: 13
     column: 4
   end_location:
     row: 13
+    column: 41
+  fix:
+    patch:
+      content: ""
+      location:
+        row: 13
+        column: 0
+      end_location:
+        row: 14
+        column: 0
+    applied: false
+- kind:
+    UnnecessaryFutureImport:
+      - generators
+  location:
+    row: 14
+    column: 4
+  end_location:
+    row: 14
     column: 53
   fix:
     patch:
       content: from __future__ import invalid_module
       location:
-        row: 13
+        row: 14
         column: 4
       end_location:
-        row: 13
+        row: 14
         column: 53
     applied: false