Unnamed repository; edit this file 'description' to name the repository.
Diffstat (limited to 'crates/ide-diagnostics/src/handlers/inactive_code.rs')
-rw-r--r--crates/ide-diagnostics/src/handlers/inactive_code.rs116
1 files changed, 116 insertions, 0 deletions
diff --git a/crates/ide-diagnostics/src/handlers/inactive_code.rs b/crates/ide-diagnostics/src/handlers/inactive_code.rs
new file mode 100644
index 0000000000..155bbc569d
--- /dev/null
+++ b/crates/ide-diagnostics/src/handlers/inactive_code.rs
@@ -0,0 +1,116 @@
+use cfg::DnfExpr;
+use stdx::format_to;
+
+use crate::{Diagnostic, DiagnosticsContext, Severity};
+
+// Diagnostic: inactive-code
+//
+// This diagnostic is shown for code with inactive `#[cfg]` attributes.
+pub(crate) fn inactive_code(
+ ctx: &DiagnosticsContext<'_>,
+ d: &hir::InactiveCode,
+) -> Option<Diagnostic> {
+ // If there's inactive code somewhere in a macro, don't propagate to the call-site.
+ if d.node.file_id.is_macro() {
+ return None;
+ }
+
+ let inactive = DnfExpr::new(d.cfg.clone()).why_inactive(&d.opts);
+ let mut message = "code is inactive due to #[cfg] directives".to_string();
+
+ if let Some(inactive) = inactive {
+ format_to!(message, ": {}", inactive);
+ }
+
+ let res = Diagnostic::new(
+ "inactive-code",
+ message,
+ ctx.sema.diagnostics_display_range(d.node.clone()).range,
+ )
+ .severity(Severity::WeakWarning)
+ .with_unused(true);
+ Some(res)
+}
+
+#[cfg(test)]
+mod tests {
+ use crate::{tests::check_diagnostics_with_config, DiagnosticsConfig};
+
+ pub(crate) fn check(ra_fixture: &str) {
+ let config = DiagnosticsConfig::default();
+ check_diagnostics_with_config(config, ra_fixture)
+ }
+
+ #[test]
+ fn cfg_diagnostics() {
+ check(
+ r#"
+fn f() {
+ // The three g̶e̶n̶d̶e̶r̶s̶ statements:
+
+ #[cfg(a)] fn f() {} // Item statement
+ //^^^^^^^^^^^^^^^^^^^ weak: code is inactive due to #[cfg] directives: a is disabled
+ #[cfg(a)] {} // Expression statement
+ //^^^^^^^^^^^^ weak: code is inactive due to #[cfg] directives: a is disabled
+ #[cfg(a)] let x = 0; // let statement
+ //^^^^^^^^^^^^^^^^^^^^ weak: code is inactive due to #[cfg] directives: a is disabled
+
+ abc(#[cfg(a)] 0);
+ //^^^^^^^^^^^ weak: code is inactive due to #[cfg] directives: a is disabled
+ let x = Struct {
+ #[cfg(a)] f: 0,
+ //^^^^^^^^^^^^^^ weak: code is inactive due to #[cfg] directives: a is disabled
+ };
+ match () {
+ () => (),
+ #[cfg(a)] () => (),
+ //^^^^^^^^^^^^^^^^^^^ weak: code is inactive due to #[cfg] directives: a is disabled
+ }
+
+ #[cfg(a)] 0 // Trailing expression of block
+ //^^^^^^^^^^^ weak: code is inactive due to #[cfg] directives: a is disabled
+}
+ "#,
+ );
+ }
+
+ #[test]
+ fn inactive_item() {
+ // Additional tests in `cfg` crate. This only tests disabled cfgs.
+
+ check(
+ r#"
+ #[cfg(no)] pub fn f() {}
+ //^^^^^^^^^^^^^^^^^^^^^^^^ weak: code is inactive due to #[cfg] directives: no is disabled
+
+ #[cfg(no)] #[cfg(no2)] mod m;
+ //^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ weak: code is inactive due to #[cfg] directives: no and no2 are disabled
+
+ #[cfg(all(not(a), b))] enum E {}
+ //^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ weak: code is inactive due to #[cfg] directives: b is disabled
+
+ #[cfg(feature = "std")] use std;
+ //^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ weak: code is inactive due to #[cfg] directives: feature = "std" is disabled
+"#,
+ );
+ }
+
+ /// Tests that `cfg` attributes behind `cfg_attr` is handled properly.
+ #[test]
+ fn inactive_via_cfg_attr() {
+ cov_mark::check!(cfg_attr_active);
+ check(
+ r#"
+ #[cfg_attr(not(never), cfg(no))] fn f() {}
+ //^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ weak: code is inactive due to #[cfg] directives: no is disabled
+
+ #[cfg_attr(not(never), cfg(not(no)))] fn f() {}
+
+ #[cfg_attr(never, cfg(no))] fn g() {}
+
+ #[cfg_attr(not(never), inline, cfg(no))] fn h() {}
+ //^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ weak: code is inactive due to #[cfg] directives: no is disabled
+"#,
+ );
+ }
+}