fix #102806, suggest use .. to fill in the rest of the fields of Struct

src/test/ui/parser/issue-102806.rs

@@ -0,0 +1,22 @@
+#![allow(dead_code)]
+
+struct V3 {
+    x: f32,
+    y: f32,
+    z: f32,
+}
+
+fn pz(v: V3) {
+    let _ = V3 { z: 0.0, ...v};
+    //~^ ERROR expected `..`
+    //~| ERROR missing fields `x` and `y` in initializer of `V3`
+    let _ = V3 { z: 0.0, ... };
+    //~^ expected identifier
+    //~| ERROR missing fields `x` and `y` in initializer of `V3`
+
+    let _ = V3 { z: 0.0, ...Default::default() };
+    //~^ ERROR expected `..`
+    //~| ERROR missing fields `x` and `y` in initializer of `V3`
+}
+
+fn main() {}

src/test/ui/parser/issue-102806.stderr

@@ -0,0 +1,51 @@
+error: expected `..`, found `...`
+  --> $DIR/issue-102806.rs:10:26
+   |
+LL |     let _ = V3 { z: 0.0, ...v};
+   |                          ^^^
+   |
+help: use `..` to fill in the rest of the fields
+   |
+LL |     let _ = V3 { z: 0.0, ..v};
+   |                          ~~
+
+error: expected identifier, found `...`
+  --> $DIR/issue-102806.rs:13:26
+   |
+LL |     let _ = V3 { z: 0.0, ... };
+   |             --           ^^^ expected identifier
+   |             |
+   |             while parsing this struct
+
+error: expected `..`, found `...`
+  --> $DIR/issue-102806.rs:17:26
+   |
+LL |     let _ = V3 { z: 0.0, ...Default::default() };
+   |                          ^^^
+   |
+help: use `..` to fill in the rest of the fields
+   |
+LL |     let _ = V3 { z: 0.0, ..Default::default() };
+   |                          ~~
+
+error[E0063]: missing fields `x` and `y` in initializer of `V3`
+  --> $DIR/issue-102806.rs:10:13
+   |
+LL |     let _ = V3 { z: 0.0, ...v};
+   |             ^^ missing `x` and `y`
+
+error[E0063]: missing fields `x` and `y` in initializer of `V3`
+  --> $DIR/issue-102806.rs:13:13
+   |
+LL |     let _ = V3 { z: 0.0, ... };
+   |             ^^ missing `x` and `y`
+
+error[E0063]: missing fields `x` and `y` in initializer of `V3`
+  --> $DIR/issue-102806.rs:17:13
+   |
+LL |     let _ = V3 { z: 0.0, ...Default::default() };
+   |             ^^ missing `x` and `y`
+
+error: aborting due to 6 previous errors
+
+For more information about this error, try `rustc --explain E0063`.