fix: Amend error message when deriving enums

miguelff · miguelff · commit dae2bb765f14 · 2022-08-26T16:57:42.000+02:00
Backported from v4. Original change: #4118
diff --git a/clap_derive/src/derives/value_enum.rs b/clap_derive/src/derives/value_enum.rs
@@ -84,7 +84,7 @@ fn lits(
                 None
             } else {
                 if !matches!(variant.fields, Fields::Unit) {
-                    abort!(variant.span(), "`#[derive(ValueEnum)]` only supports non-unit variants, unless they are skipped");
+                    abort!(variant.span(), "`#[derive(ValueEnum)]` only supports unit variants. Non-unit variants must be skipped");
                 }
                 let fields = attrs.field_methods(false);
                 let name = attrs.cased_name();
diff --git a/tests/derive_ui/value_enum_non_unit.stderr b/tests/derive_ui/value_enum_non_unit.stderr
@@ -1,4 +1,4 @@
-error: `#[derive(ValueEnum)]` only supports non-unit variants, unless they are skipped
+error: `#[derive(ValueEnum)]` only supports unit variants. Non-unit variants must be skipped
  --> tests/derive_ui/value_enum_non_unit.rs:5:5
   |
 5 |     Foo(usize),

Original file line number	Diff line number	Diff line change
`@@ -84,7 +84,7 @@ fn lits(`
`84`	`84`	`None`
`85`	`85`	`} else {`
`86`	`86`	`if !matches!(variant.fields, Fields::Unit) {`
`87`		- abort!(variant.span(), "`#[derive(ValueEnum)]` only supports non-unit variants, unless they are skipped");
	`87`	+ abort!(variant.span(), "`#[derive(ValueEnum)]` only supports unit variants. Non-unit variants must be skipped");
`88`	`88`	`}`
`89`	`89`	`let fields = attrs.field_methods(false);`
`90`	`90`	`let name = attrs.cased_name();`
Original file line number	Diff line number	Diff line change
`@@ -1,4 +1,4 @@`
`1`		-error: `#[derive(ValueEnum)]` only supports non-unit variants, unless they are skipped
	`1`	+error: `#[derive(ValueEnum)]` only supports unit variants. Non-unit variants must be skipped
`2`	`2`	`--> tests/derive_ui/value_enum_non_unit.rs:5:5`
`3`	`3`	`\|`
`4`	`4`	`5 \| Foo(usize),`