1 files changed, 171 insertions, 0 deletions

diff --git a/src/test/ui/parser/issues/issue-35813-postfix-after-cast.rs b/src/test/ui/parser/issues/issue-35813-postfix-after-cast.rs
new file mode 100644
index 000000000..7bd4b3a16
--- /dev/null
+++ b/src/test/ui/parser/issues/issue-35813-postfix-after-cast.rs
@@ -0,0 +1,171 @@
+// edition:2018
+#![crate_type = "lib"]
+#![feature(type_ascription)]
+use std::future::Future;
+use std::pin::Pin;
+
+// This tests the parser for "x as Y[z]". It errors, but we want to give useful
+// errors and parse such that further code gives useful errors.
+pub fn index_after_as_cast() {
+    vec![1, 2, 3] as Vec<i32>[0];
+    //~^ ERROR: cast cannot be followed by indexing
+    vec![1, 2, 3]: Vec<i32>[0];
+    //~^ ERROR: type ascription cannot be followed by indexing
+}
+
+pub fn index_after_cast_to_index() {
+    (&[0]) as &[i32][0];
+    //~^ ERROR: cast cannot be followed by indexing
+    (&[0i32]): &[i32; 1][0];
+    //~^ ERROR: type ascription cannot be followed by indexing
+}
+
+pub fn cast_after_cast() {
+    if 5u64 as i32 as u16 == 0u16 {
+
+    }
+    if 5u64: u64: u64 == 0u64 {
+
+    }
+    let _ = 5u64: u64: u64 as u8 as i8 == 9i8;
+    let _ = 0i32: i32: i32;
+    let _ = 0 as i32: i32;
+    let _ = 0i32: i32 as i32;
+    let _ = 0 as i32 as i32;
+    let _ = 0i32: i32: i32 as u32 as i32;
+}
+
+pub fn cast_cast_method_call() {
+    let _ = 0i32: i32: i32.count_ones();
+    //~^ ERROR: type ascription cannot be followed by a method call
+    let _ = 0 as i32: i32.count_ones();
+    //~^ ERROR: type ascription cannot be followed by a method call
+    let _ = 0i32: i32 as i32.count_ones();
+    //~^ ERROR: cast cannot be followed by a method call
+    let _ = 0 as i32 as i32.count_ones();
+    //~^ ERROR: cast cannot be followed by a method call
+    let _ = 0i32: i32: i32 as u32 as i32.count_ones();
+    //~^ ERROR: cast cannot be followed by a method call
+    let _ = 0i32: i32.count_ones(): u32;
+    //~^ ERROR: type ascription cannot be followed by a method call
+    let _ = 0 as i32.count_ones(): u32;
+    //~^ ERROR: cast cannot be followed by a method call
+    let _ = 0i32: i32.count_ones() as u32;
+    //~^ ERROR: type ascription cannot be followed by a method call
+    let _ = 0 as i32.count_ones() as u32;
+    //~^ ERROR: cast cannot be followed by a method call
+    let _ = 0i32: i32: i32.count_ones() as u32 as i32;
+    //~^ ERROR: type ascription cannot be followed by a method call
+}
+
+pub fn multiline_error() {
+    let _ = 0
+        as i32
+        .count_ones();
+    //~^^^ ERROR: cast cannot be followed by a method call
+}
+
+// this tests that the precedence for `!x as Y.Z` is still what we expect
+pub fn precedence() {
+    let x: i32 = &vec![1, 2, 3] as &Vec<i32>[0];
+    //~^ ERROR: cast cannot be followed by indexing
+}
+
+pub fn method_calls() {
+    0 as i32.max(0);
+    //~^ ERROR: cast cannot be followed by a method call
+    0: i32.max(0);
+    //~^ ERROR: type ascription cannot be followed by a method call
+}
+
+pub fn complex() {
+    let _ = format!(
+        "{} and {}",
+        if true { 33 } else { 44 } as i32.max(0),
+        //~^ ERROR: cast cannot be followed by a method call
+        if true { 33 } else { 44 }: i32.max(0)
+        //~^ ERROR: type ascription cannot be followed by a method call
+    );
+}
+
+pub fn in_condition() {
+    if 5u64 as i32.max(0) == 0 {
+        //~^ ERROR: cast cannot be followed by a method call
+    }
+    if 5u64: u64.max(0) == 0 {
+        //~^ ERROR: type ascription cannot be followed by a method call
+    }
+}
+
+pub fn inside_block() {
+    let _ = if true {
+        5u64 as u32.max(0) == 0
+        //~^ ERROR: cast cannot be followed by a method call
+    } else { false };
+    let _ = if true {
+        5u64: u64.max(0) == 0
+        //~^ ERROR: type ascription cannot be followed by a method call
+    } else { false };
+}
+
+static bar: &[i32] = &(&[1,2,3] as &[i32][0..1]);
+//~^ ERROR: cast cannot be followed by indexing
+
+static bar2: &[i32] = &(&[1i32,2,3]: &[i32; 3][0..1]);
+//~^ ERROR: type ascription cannot be followed by indexing
+
+
+pub fn cast_then_try() -> Result<u64,u64> {
+    Err(0u64) as Result<u64,u64>?;
+    //~^ ERROR: cast cannot be followed by `?`
+    Err(0u64): Result<u64,u64>?;
+    //~^ ERROR: type ascription cannot be followed by `?`
+    Ok(1)
+}
+
+
+pub fn cast_then_call() {
+    type F = fn(u8);
+    // type ascription won't actually do [unique drop fn type] -> fn(u8) casts.
+    let drop_ptr = drop as fn(u8);
+    drop as F();
+    //~^ ERROR: parenthesized type parameters may only be used with a `Fn` trait [E0214]
+    drop_ptr: F();
+    //~^ ERROR: parenthesized type parameters may only be used with a `Fn` trait [E0214]
+}
+
+pub fn cast_to_fn_should_work() {
+    let drop_ptr = drop as fn(u8);
+    drop as fn(u8);
+    drop_ptr: fn(u8);
+}
+
+pub fn parens_after_cast_error() {
+    let drop_ptr = drop as fn(u8);
+    drop as fn(u8)(0);
+    //~^ ERROR: cast cannot be followed by a function call
+    drop_ptr: fn(u8)(0);
+    //~^ ERROR: type ascription cannot be followed by a function call
+}
+
+pub async fn cast_then_await() {
+    Box::pin(noop()) as Pin<Box<dyn Future<Output = ()>>>.await;
+    //~^ ERROR: cast cannot be followed by `.await`
+
+    Box::pin(noop()): Pin<Box<_>>.await;
+    //~^ ERROR: type ascription cannot be followed by `.await`
+}
+
+pub async fn noop() {}
+
+#[derive(Default)]
+pub struct Foo {
+    pub bar: u32,
+}
+
+pub fn struct_field() {
+    Foo::default() as Foo.bar;
+    //~^ ERROR: cannot be followed by a field access
+    Foo::default(): Foo.bar;
+    //~^ ERROR: type ascription cannot be followed by a field access
+}