Rollup merge of #103405 - chenyukang:yukang/fix-103381-and-if, r=compiler-errors

Detect incorrect chaining of if and if let conditions and recover

Fixes #103381

src/test/ui/parser/issue-103381.fixed

@@ -0,0 +1,59 @@
+// run-rustfix
+
+#![feature(let_chains)]
+#![allow(unused_variables)]
+#![allow(dead_code)]
+#![allow(irrefutable_let_patterns)]
+
+fn err_some(b: bool, x: Option<u32>) {
+    if b && let Some(x) = x {}
+    //~^ ERROR unexpected `if` in the condition expression
+}
+
+fn err_none(b: bool, x: Option<u32>) {
+    if b && let None = x {}
+    //~^ ERROR unexpected `if` in the condition expression
+}
+
+fn err_bool_1() {
+    if true && true { true } else { false };
+    //~^ ERROR unexpected `if` in the condition expression
+}
+
+fn err_bool_2() {
+    if true && false { true } else { false };
+    //~^ ERROR unexpected `if` in the condition expression
+}
+
+fn should_ok_1() {
+    if true && if let x = 1 { true } else { true } {}
+}
+
+fn should_ok_2() {
+    if true && if let 1 = 1 { true } else { true } {}
+}
+
+fn should_ok_3() {
+    if true && if true { true } else { false } {}
+}
+
+fn shoule_match_ok() {
+    #[cfg(feature = "full")]
+    {
+        let a = 1;
+        let b = 2;
+        if match a {
+            1 if b == 1 => true,
+            _ => false,
+        } && if a > 1 { true } else { false }
+        {
+            true
+        }
+    }
+}
+
+fn should_ok_in_nested() {
+    if true && if true { true } else { false } { true } else { false };
+}
+
+fn main() {}

src/test/ui/parser/issue-103381.rs

@@ -0,0 +1,59 @@
+// run-rustfix
+
+#![feature(let_chains)]
+#![allow(unused_variables)]
+#![allow(dead_code)]
+#![allow(irrefutable_let_patterns)]
+
+fn err_some(b: bool, x: Option<u32>) {
+    if b && if let Some(x) = x {}
+    //~^ ERROR unexpected `if` in the condition expression
+}
+
+fn err_none(b: bool, x: Option<u32>) {
+    if b && if let None = x {}
+    //~^ ERROR unexpected `if` in the condition expression
+}
+
+fn err_bool_1() {
+    if true && if true { true } else { false };
+    //~^ ERROR unexpected `if` in the condition expression
+}
+
+fn err_bool_2() {
+    if true && if false { true } else { false };
+    //~^ ERROR unexpected `if` in the condition expression
+}
+
+fn should_ok_1() {
+    if true && if let x = 1 { true } else { true } {}
+}
+
+fn should_ok_2() {
+    if true && if let 1 = 1 { true } else { true } {}
+}
+
+fn should_ok_3() {
+    if true && if true { true } else { false } {}
+}
+
+fn shoule_match_ok() {
+    #[cfg(feature = "full")]
+    {
+        let a = 1;
+        let b = 2;
+        if match a {
+            1 if b == 1 => true,
+            _ => false,
+        } && if a > 1 { true } else { false }
+        {
+            true
+        }
+    }
+}
+
+fn should_ok_in_nested() {
+    if true && if true { true } else { false } { true } else { false };
+}
+
+fn main() {}

src/test/ui/parser/issue-103381.stderr

@@ -0,0 +1,50 @@
+error: unexpected `if` in the condition expression
+  --> $DIR/issue-103381.rs:9:12
+   |
+LL |     if b && if let Some(x) = x {}
+   |            ^^^^
+   |
+help: remove the `if`
+   |
+LL -     if b && if let Some(x) = x {}
+LL +     if b && let Some(x) = x {}
+   |
+
+error: unexpected `if` in the condition expression
+  --> $DIR/issue-103381.rs:14:12
+   |
+LL |     if b && if let None = x {}
+   |            ^^^^
+   |
+help: remove the `if`
+   |
+LL -     if b && if let None = x {}
+LL +     if b && let None = x {}
+   |
+
+error: unexpected `if` in the condition expression
+  --> $DIR/issue-103381.rs:19:15
+   |
+LL |     if true && if true { true } else { false };
+   |               ^^^^
+   |
+help: remove the `if`
+   |
+LL -     if true && if true { true } else { false };
+LL +     if true && true { true } else { false };
+   |
+
+error: unexpected `if` in the condition expression
+  --> $DIR/issue-103381.rs:24:15
+   |
+LL |     if true && if false { true } else { false };
+   |               ^^^^
+   |
+help: remove the `if`
+   |
+LL -     if true && if false { true } else { false };
+LL +     if true && false { true } else { false };
+   |
+
+error: aborting due to 4 previous errors
+