From 5877c4fea5558c902b0e2747bdf5215edc462c93 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Brais=20Gab=C3=ADn?= <braisgabin@gmail.com>
Date: Tue, 16 Aug 2022 21:18:08 +0200
Subject: [PATCH] Warn about enabled rules that are not going to run

---
 .../io/gitlab/arturbosch/detekt/core/Analyzer.kt | 16 ++++++++++++++++
 .../arturbosch/detekt/core/AnalyzerSpec.kt       |  8 ++++++--
 2 files changed, 22 insertions(+), 2 deletions(-)

diff --git a/detekt-core/src/main/kotlin/io/gitlab/arturbosch/detekt/core/Analyzer.kt b/detekt-core/src/main/kotlin/io/gitlab/arturbosch/detekt/core/Analyzer.kt
index d469dadcf86..2be31a21c3e 100644
--- a/detekt-core/src/main/kotlin/io/gitlab/arturbosch/detekt/core/Analyzer.kt
+++ b/detekt-core/src/main/kotlin/io/gitlab/arturbosch/detekt/core/Analyzer.kt
@@ -53,6 +53,9 @@ internal class Analyzer(
             } else {
                 runSync(ktFiles, bindingContext, compilerResources)
             }
+        if (bindingContext == BindingContext.EMPTY) {
+            warnAboutEnabledRequiresTypeResolutionRules(settings::info)
+        }
 
         val findingsPerRuleSet = HashMap<RuleSetId, List<Finding>>()
         for (findings in findingsPerFile) {
@@ -140,6 +143,19 @@ internal class Analyzer(
 
         return result
     }
+
+    private fun warnAboutEnabledRequiresTypeResolutionRules(log: (String) -> Unit) {
+        providers.asSequence()
+            .map { it to config.subConfig(it.ruleSetId) }
+            .filter { (_, ruleSetConfig) -> ruleSetConfig.isActive() }
+            .map { (provider, ruleSetConfig) -> provider.instance(ruleSetConfig) to ruleSetConfig }
+            .flatMap { (ruleSet, _) -> ruleSet.rules.asSequence() }
+            .filter { rule -> (rule as? Rule)?.active == true }
+            .filter { rule -> rule::class.hasAnnotation<RequiresTypeResolution>() }
+            .forEach { rule ->
+                log("The rule '${rule.ruleId}' requires type resolution but it was run without it.")
+            }
+    }
 }
 
 private fun filterSuppressedFindings(rule: BaseRule, bindingContext: BindingContext): List<Finding> {
diff --git a/detekt-core/src/test/kotlin/io/gitlab/arturbosch/detekt/core/AnalyzerSpec.kt b/detekt-core/src/test/kotlin/io/gitlab/arturbosch/detekt/core/AnalyzerSpec.kt
index 5ed0993ef36..952149dfcca 100644
--- a/detekt-core/src/test/kotlin/io/gitlab/arturbosch/detekt/core/AnalyzerSpec.kt
+++ b/detekt-core/src/test/kotlin/io/gitlab/arturbosch/detekt/core/AnalyzerSpec.kt
@@ -74,7 +74,9 @@ class AnalyzerSpec(val env: KotlinCoreEnvironment) {
             val analyzer = Analyzer(settings, listOf(StyleRuleSetProvider()), emptyList())
 
             assertThat(settings.use { analyzer.run(listOf(compileForTest(testFile))) }.values.flatten()).isEmpty()
-            assertThat(output.toString()).isEmpty()
+            assertThat(output.toString()).isEqualTo(
+                "The rule 'RequiresTypeResolutionMaxLineLength' requires type resolution but it was run without it.\n"
+            )
         }
 
         @Test
@@ -89,7 +91,9 @@ class AnalyzerSpec(val env: KotlinCoreEnvironment) {
             val analyzer = Analyzer(settings, listOf(StyleRuleSetProvider(30)), emptyList())
 
             assertThat(settings.use { analyzer.run(listOf(compileForTest(testFile))) }.values.flatten()).hasSize(1)
-            assertThat(output.toString()).isEmpty()
+            assertThat(output.toString()).isEqualTo(
+                "The rule 'RequiresTypeResolutionMaxLineLength' requires type resolution but it was run without it.\n"
+            )
         }
 
         @Test