diagnostic descriptor: redundant_assignment

Summary:
As title.

This also fully removes the now-empty `semantic_diagnostics` function

Reviewed By: robertoaloi

Differential Revision: D55740827

fbshipit-source-id: c207bcc6de2f33becccc341ac1c8112792344c1e

crates/ide/src/diagnostics.rs

@@ -514,7 +514,6 @@ pub fn native_diagnostics(
         config
             .lints_from_config
             .get_diagnostics(&mut res, &sema, file_id);
-        semantic_diagnostics(&mut res, &sema, file_id, file_kind, config);
         // @fb-only: meta_only::diagnostics(&mut res, &sema, file_id);
         syntax_diagnostics(&sema, &parse, &mut res, file_id);
         diagnostics_from_descriptors(
@@ -564,6 +563,7 @@ pub fn diagnostics_descriptors<'a>() -> Vec<&'a DiagnosticDescriptor<'a>> {
     vec![
         &unused_function_args::DESCRIPTOR,
         &trivial_match::DESCRIPTOR,
+        &redundant_assignment::DESCRIPTOR,
         &unused_macro::DESCRIPTOR,
         &unused_record_field::DESCRIPTOR,
         &mutable_variable::DESCRIPTOR,
@@ -655,21 +655,6 @@ fn widen_range(range: TextRange) -> TextRange {
     }
 }
 
-pub fn semantic_diagnostics(
-    res: &mut Vec<Diagnostic>,
-    sema: &Semantic,
-    file_id: FileId,
-    _file_kind: FileKind,
-    config: &DiagnosticsConfig,
-) {
-    if config.include_generated || !sema.db.is_generated(file_id) {
-        // TODO: disable this check when T151727890 and T151605845 are resolved
-        if config.experimental {
-            redundant_assignment::redundant_assignment(res, sema, file_id);
-        }
-    }
-}
-
 pub fn syntax_diagnostics(
     sema: &Semantic,
     parse: &Parse<ast::SourceFile>,

crates/ide/src/diagnostics/redundant_assignment.rs

@@ -29,14 +29,28 @@ use hir::Semantic;
 use hir::Strategy;
 
 use super::Diagnostic;
+use super::DiagnosticConditions;
+use super::DiagnosticDescriptor;
 use super::Severity;
 use crate::codemod_helpers::check_is_only_place_where_var_is_defined_ast;
 use crate::codemod_helpers::check_var_has_references;
 use crate::diagnostics::Category;
 use crate::diagnostics::DiagnosticCode;
 use crate::fix;
 
-pub(crate) fn redundant_assignment(diags: &mut Vec<Diagnostic>, sema: &Semantic, file_id: FileId) {
+pub(crate) static DESCRIPTOR: DiagnosticDescriptor = DiagnosticDescriptor {
+    conditions: DiagnosticConditions {
+        // TODO: disable this check when T151727890 and T151605845 are resolved
+        experimental: true,
+        include_generated: false,
+        include_tests: true,
+    },
+    checker: &|diags, sema, file_id, _ext| {
+        redundant_assignment(diags, sema, file_id);
+    },
+};
+
+fn redundant_assignment(diags: &mut Vec<Diagnostic>, sema: &Semantic, file_id: FileId) {
     if sema.db.is_generated(file_id) {
         // No point asking for changes to generated files
         return;