From 7c5d4a41459abeb40eea734efaf08657602815cb Mon Sep 17 00:00:00 2001 From: JarredAllen <jarredallen73@gmail.com> Date: Fri, 17 Jul 2020 09:27:43 -0700 Subject: [PATCH 1/2] Add test for correct behavior --- tests/ui/redundant_pattern_matching.fixed | 3 + tests/ui/redundant_pattern_matching.rs | 3 + tests/ui/redundant_pattern_matching.stderr | 68 ++++++++++++---------- 3 files changed, 43 insertions(+), 31 deletions(-) diff --git a/tests/ui/redundant_pattern_matching.fixed b/tests/ui/redundant_pattern_matching.fixed index ce8582d2b22..adbff8af8d9 100644 --- a/tests/ui/redundant_pattern_matching.fixed +++ b/tests/ui/redundant_pattern_matching.fixed @@ -11,6 +11,9 @@ )] fn main() { + let result: Result<usize, usize> = Err(5); + if result.is_ok() {} + if Ok::<i32, i32>(42).is_ok() {} if Err::<i32, i32>(42).is_err() {} diff --git a/tests/ui/redundant_pattern_matching.rs b/tests/ui/redundant_pattern_matching.rs index a3a9aa40e3b..4c2870e7803 100644 --- a/tests/ui/redundant_pattern_matching.rs +++ b/tests/ui/redundant_pattern_matching.rs @@ -11,6 +11,9 @@ )] fn main() { + let result: Result<usize, usize> = Err(5); + if let Ok(_) = &result {} + if let Ok(_) = Ok::<i32, i32>(42) {} if let Err(_) = Err::<i32, i32>(42) {} diff --git a/tests/ui/redundant_pattern_matching.stderr b/tests/ui/redundant_pattern_matching.stderr index 25d1476062e..d3c9ceaa3d7 100644 --- a/tests/ui/redundant_pattern_matching.stderr +++ b/tests/ui/redundant_pattern_matching.stderr @@ -1,73 +1,79 @@ error: redundant pattern matching, consider using `is_ok()` - --> $DIR/redundant_pattern_matching.rs:14:12 + --> $DIR/redundant_pattern_matching.rs:15:12 | -LL | if let Ok(_) = Ok::<i32, i32>(42) {} - | -------^^^^^--------------------- help: try this: `if Ok::<i32, i32>(42).is_ok()` +LL | if let Ok(_) = &result {} + | -------^^^^^---------- help: try this: `if result.is_ok()` | = note: `-D clippy::redundant-pattern-matching` implied by `-D warnings` +error: redundant pattern matching, consider using `is_ok()` + --> $DIR/redundant_pattern_matching.rs:17:12 + | +LL | if let Ok(_) = Ok::<i32, i32>(42) {} + | -------^^^^^--------------------- help: try this: `if Ok::<i32, i32>(42).is_ok()` + error: redundant pattern matching, consider using `is_err()` - --> $DIR/redundant_pattern_matching.rs:16:12 + --> $DIR/redundant_pattern_matching.rs:19:12 | LL | if let Err(_) = Err::<i32, i32>(42) {} | -------^^^^^^---------------------- help: try this: `if Err::<i32, i32>(42).is_err()` error: redundant pattern matching, consider using `is_none()` - --> $DIR/redundant_pattern_matching.rs:18:12 + --> $DIR/redundant_pattern_matching.rs:21:12 | LL | if let None = None::<()> {} | -------^^^^------------- help: try this: `if None::<()>.is_none()` error: redundant pattern matching, consider using `is_some()` - --> $DIR/redundant_pattern_matching.rs:20:12 + --> $DIR/redundant_pattern_matching.rs:23:12 | LL | if let Some(_) = Some(42) {} | -------^^^^^^^----------- help: try this: `if Some(42).is_some()` error: redundant pattern matching, consider using `is_some()` - --> $DIR/redundant_pattern_matching.rs:22:12 + --> $DIR/redundant_pattern_matching.rs:25:12 | LL | if let Some(_) = Some(42) { | -------^^^^^^^----------- help: try this: `if Some(42).is_some()` error: redundant pattern matching, consider using `is_some()` - --> $DIR/redundant_pattern_matching.rs:28:15 + --> $DIR/redundant_pattern_matching.rs:31:15 | LL | while let Some(_) = Some(42) {} | ----------^^^^^^^----------- help: try this: `while Some(42).is_some()` error: redundant pattern matching, consider using `is_none()` - --> $DIR/redundant_pattern_matching.rs:30:15 + --> $DIR/redundant_pattern_matching.rs:33:15 | LL | while let None = Some(42) {} | ----------^^^^----------- help: try this: `while Some(42).is_none()` error: redundant pattern matching, consider using `is_none()` - --> $DIR/redundant_pattern_matching.rs:32:15 + --> $DIR/redundant_pattern_matching.rs:35:15 | LL | while let None = None::<()> {} | ----------^^^^------------- help: try this: `while None::<()>.is_none()` error: redundant pattern matching, consider using `is_ok()` - --> $DIR/redundant_pattern_matching.rs:34:15 + --> $DIR/redundant_pattern_matching.rs:37:15 | LL | while let Ok(_) = Ok::<i32, i32>(10) {} | ----------^^^^^--------------------- help: try this: `while Ok::<i32, i32>(10).is_ok()` error: redundant pattern matching, consider using `is_err()` - --> $DIR/redundant_pattern_matching.rs:36:15 + --> $DIR/redundant_pattern_matching.rs:39:15 | LL | while let Err(_) = Ok::<i32, i32>(10) {} | ----------^^^^^^--------------------- help: try this: `while Ok::<i32, i32>(10).is_err()` error: redundant pattern matching, consider using `is_some()` - --> $DIR/redundant_pattern_matching.rs:39:15 + --> $DIR/redundant_pattern_matching.rs:42:15 | LL | while let Some(_) = v.pop() { | ----------^^^^^^^---------- help: try this: `while v.pop().is_some()` error: redundant pattern matching, consider using `is_ok()` - --> $DIR/redundant_pattern_matching.rs:55:5 + --> $DIR/redundant_pattern_matching.rs:58:5 | LL | / match Ok::<i32, i32>(42) { LL | | Ok(_) => true, @@ -76,7 +82,7 @@ LL | | }; | |_____^ help: try this: `Ok::<i32, i32>(42).is_ok()` error: redundant pattern matching, consider using `is_err()` - --> $DIR/redundant_pattern_matching.rs:60:5 + --> $DIR/redundant_pattern_matching.rs:63:5 | LL | / match Ok::<i32, i32>(42) { LL | | Ok(_) => false, @@ -85,7 +91,7 @@ LL | | }; | |_____^ help: try this: `Ok::<i32, i32>(42).is_err()` error: redundant pattern matching, consider using `is_err()` - --> $DIR/redundant_pattern_matching.rs:65:5 + --> $DIR/redundant_pattern_matching.rs:68:5 | LL | / match Err::<i32, i32>(42) { LL | | Ok(_) => false, @@ -94,7 +100,7 @@ LL | | }; | |_____^ help: try this: `Err::<i32, i32>(42).is_err()` error: redundant pattern matching, consider using `is_ok()` - --> $DIR/redundant_pattern_matching.rs:70:5 + --> $DIR/redundant_pattern_matching.rs:73:5 | LL | / match Err::<i32, i32>(42) { LL | | Ok(_) => true, @@ -103,7 +109,7 @@ LL | | }; | |_____^ help: try this: `Err::<i32, i32>(42).is_ok()` error: redundant pattern matching, consider using `is_some()` - --> $DIR/redundant_pattern_matching.rs:75:5 + --> $DIR/redundant_pattern_matching.rs:78:5 | LL | / match Some(42) { LL | | Some(_) => true, @@ -112,7 +118,7 @@ LL | | }; | |_____^ help: try this: `Some(42).is_some()` error: redundant pattern matching, consider using `is_none()` - --> $DIR/redundant_pattern_matching.rs:80:5 + --> $DIR/redundant_pattern_matching.rs:83:5 | LL | / match None::<()> { LL | | Some(_) => false, @@ -121,7 +127,7 @@ LL | | }; | |_____^ help: try this: `None::<()>.is_none()` error: redundant pattern matching, consider using `is_none()` - --> $DIR/redundant_pattern_matching.rs:85:13 + --> $DIR/redundant_pattern_matching.rs:88:13 | LL | let _ = match None::<()> { | _____________^ @@ -131,64 +137,64 @@ LL | | }; | |_____^ help: try this: `None::<()>.is_none()` error: redundant pattern matching, consider using `is_ok()` - --> $DIR/redundant_pattern_matching.rs:90:20 + --> $DIR/redundant_pattern_matching.rs:93:20 | LL | let _ = if let Ok(_) = Ok::<usize, ()>(4) { true } else { false }; | -------^^^^^--------------------- help: try this: `if Ok::<usize, ()>(4).is_ok()` error: redundant pattern matching, consider using `is_some()` - --> $DIR/redundant_pattern_matching.rs:93:20 + --> $DIR/redundant_pattern_matching.rs:96:20 | LL | let x = if let Some(_) = opt { true } else { false }; | -------^^^^^^^------ help: try this: `if opt.is_some()` error: redundant pattern matching, consider using `is_some()` - --> $DIR/redundant_pattern_matching.rs:99:20 + --> $DIR/redundant_pattern_matching.rs:102:20 | LL | let _ = if let Some(_) = gen_opt() { | -------^^^^^^^------------ help: try this: `if gen_opt().is_some()` error: redundant pattern matching, consider using `is_none()` - --> $DIR/redundant_pattern_matching.rs:101:19 + --> $DIR/redundant_pattern_matching.rs:104:19 | LL | } else if let None = gen_opt() { | -------^^^^------------ help: try this: `if gen_opt().is_none()` error: redundant pattern matching, consider using `is_ok()` - --> $DIR/redundant_pattern_matching.rs:103:19 + --> $DIR/redundant_pattern_matching.rs:106:19 | LL | } else if let Ok(_) = gen_res() { | -------^^^^^------------ help: try this: `if gen_res().is_ok()` error: redundant pattern matching, consider using `is_err()` - --> $DIR/redundant_pattern_matching.rs:105:19 + --> $DIR/redundant_pattern_matching.rs:108:19 | LL | } else if let Err(_) = gen_res() { | -------^^^^^^------------ help: try this: `if gen_res().is_err()` error: redundant pattern matching, consider using `is_some()` - --> $DIR/redundant_pattern_matching.rs:138:19 + --> $DIR/redundant_pattern_matching.rs:141:19 | LL | while let Some(_) = r#try!(result_opt()) {} | ----------^^^^^^^----------------------- help: try this: `while r#try!(result_opt()).is_some()` error: redundant pattern matching, consider using `is_some()` - --> $DIR/redundant_pattern_matching.rs:139:16 + --> $DIR/redundant_pattern_matching.rs:142:16 | LL | if let Some(_) = r#try!(result_opt()) {} | -------^^^^^^^----------------------- help: try this: `if r#try!(result_opt()).is_some()` error: redundant pattern matching, consider using `is_some()` - --> $DIR/redundant_pattern_matching.rs:145:12 + --> $DIR/redundant_pattern_matching.rs:148:12 | LL | if let Some(_) = m!() {} | -------^^^^^^^------- help: try this: `if m!().is_some()` error: redundant pattern matching, consider using `is_some()` - --> $DIR/redundant_pattern_matching.rs:146:15 + --> $DIR/redundant_pattern_matching.rs:149:15 | LL | while let Some(_) = m!() {} | ----------^^^^^^^------- help: try this: `while m!().is_some()` -error: aborting due to 28 previous errors +error: aborting due to 29 previous errors From e85b590936863e88da4ccd73af9f5da0787b9609 Mon Sep 17 00:00:00 2001 From: JarredAllen <jarredallen73@gmail.com> Date: Fri, 17 Jul 2020 10:40:01 -0700 Subject: [PATCH 2/2] Fix bug in lint --- clippy_lints/src/matches.rs | 14 +++++++++++--- 1 file changed, 11 insertions(+), 3 deletions(-) diff --git a/clippy_lints/src/matches.rs b/clippy_lints/src/matches.rs index bd474c20807..fe00a48adef 100644 --- a/clippy_lints/src/matches.rs +++ b/clippy_lints/src/matches.rs @@ -1512,6 +1512,10 @@ mod redundant_pattern_match { } } + let result_expr = match &op.kind { + ExprKind::AddrOf(_, _, borrowed) => borrowed, + _ => op, + }; span_lint_and_then( cx, REDUNDANT_PATTERN_MATCHING, @@ -1524,7 +1528,7 @@ mod redundant_pattern_match { // while let ... = ... { ... } // ^^^ - let op_span = op.span.source_callsite(); + let op_span = result_expr.span.source_callsite(); // while let ... = ... { ... } // ^^^^^^^^^^^^^^^^^^^ @@ -1589,17 +1593,21 @@ mod redundant_pattern_match { }; if let Some(good_method) = found_good_method { + let span = expr.span.to(op.span); + let result_expr = match &op.kind { + ExprKind::AddrOf(_, _, borrowed) => borrowed, + _ => op, + }; span_lint_and_then( cx, REDUNDANT_PATTERN_MATCHING, expr.span, &format!("redundant pattern matching, consider using `{}`", good_method), |diag| { - let span = expr.span.to(op.span); diag.span_suggestion( span, "try this", - format!("{}.{}", snippet(cx, op.span, "_"), good_method), + format!("{}.{}", snippet(cx, result_expr.span, "_"), good_method), Applicability::MaybeIncorrect, // snippet ); },