perfguard/_rules: add constErrorNew opt rule (#49)

quasilyte · Jan 10, 2022 · fb88f2c · fb88f2c
1 parent 5a95f50
commit fb88f2c
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Showing 3 changed files with 950 additions and 922 deletions.
diff --git a/perfguard/_rules/opt_rules.go b/perfguard/_rules/opt_rules.go
@@ -67,3 +67,11 @@ func rangeValueCopy(m dsl.Matcher) {
 		Where(m["v"].Type.Size > 128).
 		Report(`every iteration copies a large object into $v`)
 }
+
+//doc:summary Detects errors.New that can be allocated exactly once
+//doc:tags    o1 score3
+func constErrorNew(m dsl.Matcher) {
+	m.Match(`errors.New($x)`).
+		Where(m["x"].Const).
+		Report(`errors with const message can be a global var, allocated only once`)
+}
diff --git a/perfguard/rulesdata/opt_rules.go b/perfguard/rulesdata/opt_rules.go