fixup! Recover more expressions in patterns

rust-lang · Jul 15, 2024 · d2ca561 · d2ca561
1 parent 8513f07
commit d2ca561
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diff --git a/compiler/rustc_parse/src/parser/pat.rs b/compiler/rustc_parse/src/parser/pat.rs
@@ -346,7 +346,7 @@ impl<'a> Parser<'a> {
     /// 0..=1 + 2
     ///     ^^^^^
     /// ```
-    /// Only the end bound is spanned in this case, and this function have no idea if there were a `..=` before `pat_span`, hence the parameter.
+    /// Only the end bound is spanned in this case, and this function has no idea if there was a `..=` before `pat_span`, hence the parameter.
     ///
     /// This function returns `Some` if a trailing expression was recovered, and said expression's span.
     #[must_use = "the pattern must be discarded as `PatKind::Err` if this function returns Some"]
@@ -360,23 +360,34 @@ impl<'a> Parser<'a> {
             return None;
         }
 
-        // Returns `true` iff `token` is a `x.y` float.
-        let is_two_tuple_indexes = |that: &Self, token: &Token| -> bool {
+        // Returns `true` iff `token` is an unsuffixed integer.
+        let is_one_tuple_index = |_: &Self, token: &Token| -> bool {
             use token::{Lit, LitKind};
 
-            let token::Literal(Lit { kind: LitKind::Float, symbol, suffix: None }) = token.kind
-            else {
-                return false;
-            };
+            matches!(
+                token.kind,
+                token::Literal(Lit { kind: LitKind::Integer, symbol: _, suffix: None })
+            )
+        };
+
+        // Returns `true` iff `token` is an unsuffixed `x.y` float.
+        let is_two_tuple_indexes = |this: &Self, token: &Token| -> bool {
+            use token::{Lit, LitKind};
 
-            matches!(that.break_up_float(symbol, token.span), DestructuredFloat::MiddleDot(..))
+            if let token::Literal(Lit { kind: LitKind::Float, symbol, suffix: None }) = token.kind
+                && let DestructuredFloat::MiddleDot(..) = this.break_up_float(symbol, token.span)
+            {
+                true
+            } else {
+                false
+            }
         };
 
         // Check for `.hello` or `.0`.
         let has_dot_expr = self.check_noexpect(&token::Dot) // `.`
             && self.look_ahead(1, |tok| {
                 tok.is_ident() // `hello`
-                || tok.is_integer_lit() // `0`
+                || is_one_tuple_index(&self, &tok) // `0`
                 || is_two_tuple_indexes(&self, &tok) // `0.0`
             });
 

diff --git a/tests/ui/parser/recover/recover-pat-exprs.rs b/tests/ui/parser/recover/recover-pat-exprs.rs
@@ -12,6 +12,23 @@ fn field_access() {
     { let x.0e0; } //~ error: expected one of `:`, `;`, `=`, `@`, or `|`, found `.`
     { let x.-0.0; } //~ error: expected one of `:`, `;`, `=`, `@`, or `|`, found `.`
     { let x.-0; } //~ error: expected one of `:`, `;`, `=`, `@`, or `|`, found `.`
+
+    { let x.0u32; } //~ error: expected one of `:`, `;`, `=`, `@`, or `|`, found `.`
+    { let x.0.0_f64; } //~ error: expected one of `:`, `;`, `=`, `@`, or `|`, found `.`
+}
+
+// ArrayExpression
+fn array_indexing() {
+    match 0 {
+        x[0] => (), //~ error: expected a pattern, found an expression
+        x[..] => (), //~ error: expected a pattern, found an expression
+    }
+
+    { let x[0, 1, 2]; } //~ error: expected one of `:`, `;`, `=`, `@`, or `|`, found `[`
+    { let x[0; 20]; } //~ error: expected one of `:`, `;`, `=`, `@`, or `|`, found `[`
+    { let x[]; } //~ error: expected one of `:`, `;`, `=`, `@`, or `|`, found `[`
+    { let (x[]); } //~ error: expected one of `)`, `,`, `@`, or `|`, found `[`
+    //~^ missing `,`
 }
 
 // MethodCallExpression, CallExpression, ErrorPropagationExpression

diff --git a/tests/ui/parser/recover/recover-pat-exprs.stderr b/tests/ui/parser/recover/recover-pat-exprs.stderr
@@ -133,8 +133,90 @@ error: expected one of `:`, `;`, `=`, `@`, or `|`, found `.`
 LL |     { let x.-0; }
    |            ^ expected one of `:`, `;`, `=`, `@`, or `|`
 
+error: expected one of `:`, `;`, `=`, `@`, or `|`, found `.`
+  --> $DIR/recover-pat-exprs.rs:16:12
+   |
+LL |     { let x.0u32; }
+   |            ^ expected one of `:`, `;`, `=`, `@`, or `|`
+
+error: expected one of `:`, `;`, `=`, `@`, or `|`, found `.`
+  --> $DIR/recover-pat-exprs.rs:17:12
+   |
+LL |     { let x.0.0_f64; }
+   |            ^ expected one of `:`, `;`, `=`, `@`, or `|`
+
+error: expected a pattern, found an expression
+  --> $DIR/recover-pat-exprs.rs:23:9
+   |
+LL |         x[0] => (),
+   |         ^^^^ arbitrary expressions are not allowed in patterns
+   |
+help: check the value in an arm guard
+   |
+LL |         val if val == x[0] => (),
+   |         ~~~ ++++++++++++++
+help: extract the expression into a `const` and refer to it
+   |
+LL +     const VAL: _ = x[0];
+LL ~     match 0 {
+LL ~         VAL => (),
+   |
+help: wrap the expression in a inline const (requires `#![feature(inline_const_pat)]`)
+   |
+LL |         const { x[0] } => (),
+   |         +++++++      +
+
 error: expected a pattern, found an expression
-  --> $DIR/recover-pat-exprs.rs:20:9
+  --> $DIR/recover-pat-exprs.rs:24:9
+   |
+LL |         x[..] => (),
+   |         ^^^^^ arbitrary expressions are not allowed in patterns
+   |
+help: check the value in an arm guard
+   |
+LL |         val if val == x[..] => (),
+   |         ~~~ +++++++++++++++
+help: extract the expression into a `const` and refer to it
+   |
+LL +     const VAL: _ = x[..];
+LL ~     match 0 {
+LL |         x[0] => (),
+LL ~         VAL => (),
+   |
+help: wrap the expression in a inline const (requires `#![feature(inline_const_pat)]`)
+   |
+LL |         const { x[..] } => (),
+   |         +++++++       +
+
+error: expected one of `:`, `;`, `=`, `@`, or `|`, found `[`
+  --> $DIR/recover-pat-exprs.rs:27:12
+   |
+LL |     { let x[0, 1, 2]; }
+   |            ^ expected one of `:`, `;`, `=`, `@`, or `|`
+
+error: expected one of `:`, `;`, `=`, `@`, or `|`, found `[`
+  --> $DIR/recover-pat-exprs.rs:28:12
+   |
+LL |     { let x[0; 20]; }
+   |            ^ expected one of `:`, `;`, `=`, `@`, or `|`
+
+error: expected one of `:`, `;`, `=`, `@`, or `|`, found `[`
+  --> $DIR/recover-pat-exprs.rs:29:12
+   |
+LL |     { let x[]; }
+   |            ^ expected one of `:`, `;`, `=`, `@`, or `|`
+
+error: expected one of `)`, `,`, `@`, or `|`, found `[`
+  --> $DIR/recover-pat-exprs.rs:30:13
+   |
+LL |     { let (x[]); }
+   |             ^
+   |             |
+   |             expected one of `)`, `,`, `@`, or `|`
+   |             help: missing `,`
+
+error: expected a pattern, found an expression
+  --> $DIR/recover-pat-exprs.rs:37:9
    |
 LL |         x.f() => (),
    |         ^^^^^ arbitrary expressions are not allowed in patterns
@@ -155,7 +237,7 @@ LL |         const { x.f() } => (),
    |         +++++++       +
 
 error: expected a pattern, found an expression
-  --> $DIR/recover-pat-exprs.rs:21:9
+  --> $DIR/recover-pat-exprs.rs:38:9
    |
 LL |         x._f() => (),
    |         ^^^^^^ arbitrary expressions are not allowed in patterns
@@ -177,7 +259,7 @@ LL |         const { x._f() } => (),
    |         +++++++        +
 
 error: expected a pattern, found an expression
-  --> $DIR/recover-pat-exprs.rs:22:9
+  --> $DIR/recover-pat-exprs.rs:39:9
    |
 LL |         x? => (),
    |         ^^ arbitrary expressions are not allowed in patterns
@@ -200,7 +282,7 @@ LL |         const { x? } => (),
    |         +++++++    +
 
 error: expected a pattern, found an expression
-  --> $DIR/recover-pat-exprs.rs:23:9
+  --> $DIR/recover-pat-exprs.rs:40:9
    |
 LL |         ().f() => (),
    |         ^^^^^^ arbitrary expressions are not allowed in patterns
@@ -224,7 +306,7 @@ LL |         const { ().f() } => (),
    |         +++++++        +
 
 error: expected a pattern, found an expression
-  --> $DIR/recover-pat-exprs.rs:24:9
+  --> $DIR/recover-pat-exprs.rs:41:9
    |
 LL |         (0, x)?.f() => (),
    |         ^^^^^^^^^^^ arbitrary expressions are not allowed in patterns
@@ -248,7 +330,7 @@ LL |         const { (0, x)?.f() } => (),
    |         +++++++             +
 
 error: expected a pattern, found an expression
-  --> $DIR/recover-pat-exprs.rs:25:9
+  --> $DIR/recover-pat-exprs.rs:42:9
    |
 LL |         x.f().g() => (),
    |         ^^^^^^^^^ arbitrary expressions are not allowed in patterns
@@ -272,7 +354,7 @@ LL |         const { x.f().g() } => (),
    |         +++++++           +
 
 error: expected a pattern, found an expression
-  --> $DIR/recover-pat-exprs.rs:26:9
+  --> $DIR/recover-pat-exprs.rs:43:9
    |
 LL |         0.f()?.g()?? => (),
    |         ^^^^^^^^^^^^ arbitrary expressions are not allowed in patterns
@@ -296,7 +378,7 @@ LL |         const { 0.f()?.g()?? } => (),
    |         +++++++              +
 
 error: expected a pattern, found an expression
-  --> $DIR/recover-pat-exprs.rs:33:9
+  --> $DIR/recover-pat-exprs.rs:50:9
    |
 LL |         x as usize => (),
    |         ^^^^^^^^^^ arbitrary expressions are not allowed in patterns
@@ -317,7 +399,7 @@ LL |         const { x as usize } => (),
    |         +++++++            +
 
 error: expected a pattern, found an expression
-  --> $DIR/recover-pat-exprs.rs:34:9
+  --> $DIR/recover-pat-exprs.rs:51:9
    |
 LL |         0 as usize => (),
    |         ^^^^^^^^^^ arbitrary expressions are not allowed in patterns
@@ -339,7 +421,7 @@ LL |         const { 0 as usize } => (),
    |         +++++++            +
 
 error: expected a pattern, found an expression
-  --> $DIR/recover-pat-exprs.rs:35:9
+  --> $DIR/recover-pat-exprs.rs:52:9
    |
 LL |         x.f().0.4 as f32 => (),
    |         ^^^^^^^^^^^^^^^^ arbitrary expressions are not allowed in patterns
@@ -362,7 +444,7 @@ LL |         const { x.f().0.4 as f32 } => (),
    |         +++++++                  +
 
 error: expected a pattern, found an expression
-  --> $DIR/recover-pat-exprs.rs:42:9
+  --> $DIR/recover-pat-exprs.rs:59:9
    |
 LL |         1 + 1 => (),
    |         ^^^^^ arbitrary expressions are not allowed in patterns
@@ -383,7 +465,7 @@ LL |         const { 1 + 1 } => (),
    |         +++++++       +
 
 error: expected a pattern, found an expression
-  --> $DIR/recover-pat-exprs.rs:43:9
+  --> $DIR/recover-pat-exprs.rs:60:9
    |
 LL |         (1 + 2) * 3 => (),
    |         ^^^^^^^^^^^ arbitrary expressions are not allowed in patterns
@@ -405,7 +487,7 @@ LL |         const { (1 + 2) * 3 } => (),
    |         +++++++             +
 
 error: left-hand side of `@` must be a binding
-  --> $DIR/recover-pat-exprs.rs:56:9
+  --> $DIR/recover-pat-exprs.rs:73:9
    |
 LL |         x.sqrt() @ .. => (),
    |         --------^^^--
@@ -416,13 +498,13 @@ LL |         x.sqrt() @ .. => (),
    = note: bindings are `x`, `mut x`, `ref x`, and `ref mut x`
 
 error: expected one of `)`, `,`, or `|`, found `+`
-  --> $DIR/recover-pat-exprs.rs:70:12
+  --> $DIR/recover-pat-exprs.rs:87:12
    |
 LL |         (_ + 1) => (),
    |            ^ expected one of `)`, `,`, or `|`
 
 error: expected a pattern, found an expression
-  --> $DIR/recover-pat-exprs.rs:54:9
+  --> $DIR/recover-pat-exprs.rs:71:9
    |
 LL |         u8::MAX.abs() => (),
    |         ^^^^^^^^^^^^^ arbitrary expressions are not allowed in patterns
@@ -443,7 +525,7 @@ LL |         const { u8::MAX.abs() } => (),
    |         +++++++               +
 
 error: expected a pattern, found an expression
-  --> $DIR/recover-pat-exprs.rs:59:17
+  --> $DIR/recover-pat-exprs.rs:76:17
    |
 LL |         z @ w @ v.u() => (),
    |                 ^^^^^ arbitrary expressions are not allowed in patterns
@@ -467,7 +549,7 @@ LL |         z @ w @ const { v.u() } => (),
    |                 +++++++       +
 
 error: expected a pattern, found an expression
-  --> $DIR/recover-pat-exprs.rs:61:9
+  --> $DIR/recover-pat-exprs.rs:78:9
    |
 LL |         y.ilog(3) => (),
    |         ^^^^^^^^^ arbitrary expressions are not allowed in patterns
@@ -491,7 +573,7 @@ LL |         const { y.ilog(3) } => (),
    |         +++++++           +
 
 error: expected a pattern, found an expression
-  --> $DIR/recover-pat-exprs.rs:63:9
+  --> $DIR/recover-pat-exprs.rs:80:9
    |
 LL |         n + 1 => (),
    |         ^^^^^ arbitrary expressions are not allowed in patterns
@@ -515,7 +597,7 @@ LL |         const { n + 1 } => (),
    |         +++++++       +
 
 error: expected a pattern, found an expression
-  --> $DIR/recover-pat-exprs.rs:65:10
+  --> $DIR/recover-pat-exprs.rs:82:10
    |
 LL |         ("".f() + 14 * 8) => (),
    |          ^^^^^^^^^^^^^^^ arbitrary expressions are not allowed in patterns
@@ -539,7 +621,7 @@ LL |         (const { "".f() + 14 * 8 }) => (),
    |          +++++++                 +
 
 error: expected a pattern, found an expression
-  --> $DIR/recover-pat-exprs.rs:68:9
+  --> $DIR/recover-pat-exprs.rs:85:9
    |
 LL |         f?() => (),
    |         ^^^^ arbitrary expressions are not allowed in patterns
@@ -563,7 +645,7 @@ LL |         const { f?() } => (),
    |         +++++++      +
 
 error: expected a pattern, found an expression
-  --> $DIR/recover-pat-exprs.rs:74:9
+  --> $DIR/recover-pat-exprs.rs:91:9
    |
 LL |     let 1 + 1 = 2;
    |         ^^^^^ arbitrary expressions are not allowed in patterns
@@ -575,7 +657,7 @@ LL +     1 + 1 = 2;
    |
 
 error: expected one of `)`, `,`, `@`, or `|`, found `*`
-  --> $DIR/recover-pat-exprs.rs:77:28
+  --> $DIR/recover-pat-exprs.rs:94:28
    |
 LL |     let b = matches!(x, (x * x | x.f()) | x[0]);
    |                            ^ expected one of `)`, `,`, `@`, or `|`
@@ -584,16 +666,16 @@ LL |     let b = matches!(x, (x * x | x.f()) | x[0]);
    = note: while parsing argument for this `pat` macro fragment
 
 error: expected a pattern, found an expression
-  --> $DIR/recover-pat-exprs.rs:48:5
+  --> $DIR/recover-pat-exprs.rs:65:5
    |
 LL |     1 + 2 * PI.cos() => 2,
    |     ^^^^^^^^^^^^^^^^ arbitrary expressions are not allowed in patterns
 
 error: expected a pattern, found an expression
-  --> $DIR/recover-pat-exprs.rs:56:9
+  --> $DIR/recover-pat-exprs.rs:73:9
    |
 LL |         x.sqrt() @ .. => (),
    |         ^^^^^^^^ arbitrary expressions are not allowed in patterns
 
-error: aborting due to 32 previous errors
+error: aborting due to 40 previous errors