Validate yaml configurations by comparing their structure - #516

detekt-api/src/main/kotlin/io/gitlab/arturbosch/detekt/api/internal/Validation.kt

@@ -1,5 +1,9 @@
 package io.gitlab.arturbosch.detekt.api.internal
 
+import io.gitlab.arturbosch.detekt.api.Config
+import io.gitlab.arturbosch.detekt.api.Notification
+import io.gitlab.arturbosch.detekt.api.YamlConfig
+
 private val identifierRegex = Regex("[aA-zZ]+([-][aA-zZ]+)*")
 
 /**
@@ -8,3 +12,47 @@ private val identifierRegex = Regex("[aA-zZ]+([-][aA-zZ]+)*")
 internal fun validateIdentifier(id: String) {
     require(id.matches(identifierRegex)) { "id must match [aA-zZ]+([-][aA-zZ]+)*" }
 }
+
+fun verifyConfig(config: Config, baseline: Config): List<Notification> {
+    if (config == Config.empty && baseline == Config.empty) {
+        return emptyList()
+    }
+
+    val notifications = mutableListOf<Notification>()
+
+    @Suppress("UNCHECKED_CAST")
+    fun testKeys(current: Map<String, Any>, base: Map<String, Any>, parentPath: String?) {
+        for (prop in current.keys) {
+
+            val propertyPath = "${if (parentPath == null) "" else "$parentPath>"}$prop"
+            if (!base.contains(prop)) {
+                notifications.add(doesNotExistsMessage(propertyPath))
+            }
+
+            val next = current[prop]?.let { it as? Map<String, Any> }
+            val nextBase = base[prop]?.let { it as? Map<String, Any> }
+
+            when {
+                next == null && nextBase != null -> notifications.add(nestedConfigExpectedMessage(propertyPath))
+                base.contains(prop) && next != null && nextBase == null ->
+                    notifications.add(unexpectedNestedConfigMessage(propertyPath))
+                next != null && nextBase != null -> testKeys(next, nextBase, propertyPath)
+            }
+        }
+    }
+
+    if (config is YamlConfig && baseline is YamlConfig) {
+        testKeys(config.properties, baseline.properties, null)
+    }
+
+    return notifications
+}
+
+internal fun doesNotExistsMessage(prop: String): Notification =
+    SimpleNotification("Property '$prop' is misspelled or does not exist.")
+
+internal fun nestedConfigExpectedMessage(prop: String): Notification =
+    SimpleNotification("Nested config expected for '$prop'.")
+
+internal fun unexpectedNestedConfigMessage(prop: String): Notification =
+    SimpleNotification("Unexpected nested config for '$prop'.")

detekt-api/src/test/kotlin/io/gitlab/arturbosch/detekt/api/internal/ConfigValidationSpec.kt

@@ -0,0 +1,60 @@
+package io.gitlab.arturbosch.detekt.api.internal
+
+import io.gitlab.arturbosch.detekt.test.yamlConfig
+import org.assertj.core.api.Assertions.assertThat
+import org.spekframework.spek2.Spek
+import org.spekframework.spek2.style.specification.describe
+
+internal class ConfigValidationSpec : Spek({
+
+    describe("validate configuration file") {
+
+        val baseline = yamlConfig("config_validation/baseline.yml")
+
+        it("passes for same config test") {
+            verifyConfig(baseline, baseline)
+        }
+
+        it("reports different rule set name") {
+            val result = verifyConfig(
+                yamlConfig("config_validation/other-ruleset-name.yml"),
+                baseline
+            )
+            assertThat(result).contains(doesNotExistsMessage("code-smell"))
+        }
+
+        it("reports different nested property names") {
+            val result = verifyConfig(
+                yamlConfig("config_validation/other-nested-property-names.yml"),
+                baseline
+            )
+            assertThat(result).contains(
+                doesNotExistsMessage("complexity>LongLongMethod"),
+                doesNotExistsMessage("complexity>LongParameterList>enabled"),
+                doesNotExistsMessage("complexity>LargeClass>howMany"),
+                doesNotExistsMessage("complexity>InnerMap>InnerKey"),
+                doesNotExistsMessage("complexity>InnerMap>Inner2>nestedActive")
+            )
+        }
+
+        it("reports different rule set name") {
+            val result = verifyConfig(
+                yamlConfig("config_validation/no-nested-config.yml"),
+                baseline
+            )
+            assertThat(result).contains(
+                nestedConfigExpectedMessage("complexity"),
+                nestedConfigExpectedMessage("style>WildcardImport")
+            )
+        }
+
+        it("reports unexpected nested configs") {
+            // note that the baseline config is now the first argument
+            val result = verifyConfig(baseline, yamlConfig("config_validation/no-value.yml"))
+            assertThat(result).contains(
+                unexpectedNestedConfigMessage("style"),
+                unexpectedNestedConfigMessage("comments")
+            )
+        }
+    }
+})

detekt-api/src/test/resources/config_validation/baseline.yml

@@ -0,0 +1,27 @@
+complexity:
+  LongMethod:
+    active: true
+    threshold: 20
+  LongParameterList:
+    active: false
+    threshold: 5
+  LargeClass:
+    active: false
+    threshold: 70
+  InnerMap:
+    Inner1:
+      active: true
+    Inner2:
+      active: true
+
+style:
+  WildcardImport:
+    active: true
+  NoElseInWhenExpression:
+    active: true
+  MagicNumber:
+    active: true
+    ignoreNumbers: '-1,0,1,2'
+
+comments:
+  active: false

detekt-api/src/test/resources/config_validation/no-nested-config.yml

@@ -0,0 +1,4 @@
+complexity: false
+
+style:
+  WildcardImport: false

detekt-api/src/test/resources/config_validation/no-value.yml

@@ -0,0 +1,3 @@
+complexity:
+style:
+comments:

detekt-api/src/test/resources/config_validation/other-nested-property-names.yml

@@ -0,0 +1,15 @@
+complexity:
+  LongLongMethod:
+    active: true
+    threshold: 20
+  LongParameterList:
+    enabled: false
+    threshold: 5
+  LargeClass:
+    active: false
+    howMany: 70
+  InnerMap:
+    InnerKey:
+      active: true
+    Inner2:
+      nestedActive: true

detekt-api/src/test/resources/config_validation/other-ruleset-name.yml

@@ -0,0 +1,15 @@
+code-smell:
+  LongMethod:
+    active: true
+    threshold: 20
+  LongParameterList:
+    active: false
+    threshold: 5
+  LargeClass:
+    active: false
+    threshold: 70
+  InnerMap:
+    Inner1:
+      active: true
+    Inner2:
+      active: true

detekt-cli/src/test/kotlin/io/gitlab/arturbosch/detekt/cli/DefaultConfigValidationSpec.kt

@@ -0,0 +1,19 @@
+package io.gitlab.arturbosch.detekt.cli
+
+import io.gitlab.arturbosch.detekt.api.internal.verifyConfig
+import io.gitlab.arturbosch.detekt.test.yamlConfig
+import org.assertj.core.api.Assertions.assertThat
+import org.spekframework.spek2.Spek
+import org.spekframework.spek2.style.specification.describe
+
+class DefaultConfigValidationSpec : Spek({
+
+    describe("default configuration is valid") {
+
+        it("is valid comparing itself") {
+            val baseline = yamlConfig("default-detekt-config.yml")
+            val result = verifyConfig(baseline, baseline)
+            assertThat(result).isEmpty()
+        }
+    }
+})