Add some requested tests

src/test/ui/parser/float-field-interpolated.rs

@@ -0,0 +1,17 @@
+struct S(u8, (u8, u8));
+
+macro_rules! generate_field_accesses {
+    ($a:tt, $b:literal, $c:expr) => {
+        let s = S(0, (0, 0));
+
+        s.$a; // OK
+        { s.$b; } //~ ERROR unexpected token: `1.1`
+                  //~| ERROR expected one of `.`, `;`, `?`, `}`, or an operator, found `1.1`
+        { s.$c; } //~ ERROR unexpected token: `1.1`
+                  //~| ERROR expected one of `.`, `;`, `?`, `}`, or an operator, found `1.1`
+    };
+}
+
+fn main() {
+    generate_field_accesses!(1.1, 1.1, 1.1);
+}

src/test/ui/parser/float-field-interpolated.stderr

@@ -0,0 +1,46 @@
+error: unexpected token: `1.1`
+  --> $DIR/float-field-interpolated.rs:8:13
+   |
+LL |         { s.$b; }
+   |             ^^
+...
+LL |     generate_field_accesses!(1.1, 1.1, 1.1);
+   |     ---------------------------------------- in this macro invocation
+   |
+   = note: this error originates in a macro (in Nightly builds, run with -Z macro-backtrace for more info)
+
+error: expected one of `.`, `;`, `?`, `}`, or an operator, found `1.1`
+  --> $DIR/float-field-interpolated.rs:8:13
+   |
+LL |         { s.$b; }
+   |             ^^ expected one of `.`, `;`, `?`, `}`, or an operator
+...
+LL |     generate_field_accesses!(1.1, 1.1, 1.1);
+   |     ---------------------------------------- in this macro invocation
+   |
+   = note: this error originates in a macro (in Nightly builds, run with -Z macro-backtrace for more info)
+
+error: unexpected token: `1.1`
+  --> $DIR/float-field-interpolated.rs:10:13
+   |
+LL |         { s.$c; }
+   |             ^^
+...
+LL |     generate_field_accesses!(1.1, 1.1, 1.1);
+   |     ---------------------------------------- in this macro invocation
+   |
+   = note: this error originates in a macro (in Nightly builds, run with -Z macro-backtrace for more info)
+
+error: expected one of `.`, `;`, `?`, `}`, or an operator, found `1.1`
+  --> $DIR/float-field-interpolated.rs:10:13
+   |
+LL |         { s.$c; }
+   |             ^^ expected one of `.`, `;`, `?`, `}`, or an operator
+...
+LL |     generate_field_accesses!(1.1, 1.1, 1.1);
+   |     ---------------------------------------- in this macro invocation
+   |
+   = note: this error originates in a macro (in Nightly builds, run with -Z macro-backtrace for more info)
+
+error: aborting due to 4 previous errors
+

src/test/ui/tuple/index-float.rs

@@ -4,6 +4,7 @@ fn main() {
     let tuple = (((),),);
 
     let _ = tuple. 0.0; // OK, whitespace
+    let _ = tuple.0. 0; // OK, whitespace
 
     let _ = tuple./*special cases*/0.0; // OK, comment
 }