refactor(scanner)!: Remove the unused ScannerConfigMatcher

The `ScannerConfigMatcher` was intended to support cases where the
`ScannerDetails.configuration` must not be matched exactly. As the
feature was not taken into use since its introduction three years ago,
replace it with a simpler approach to match either the whole
configuration or ignore the configuration to simplify code.

Signed-off-by: Martin Nonnenmacher <[email protected]>

Author: mnonnenmacher

scanner/src/main/kotlin/ScannerCriteria.kt

@@ -25,18 +25,6 @@ import org.ossreviewtoolkit.model.config.Options
 import org.semver4j.Semver
 import org.semver4j.Semver.VersionDiff
 
-/**
- * Definition of a predicate to check whether the configuration of a scanner is compatible with the requirements
- * specified by a [ScannerCriteria].
- *
- * When testing whether a scan result is compatible with specific criteria this function is invoked on the
- * scanner configuration data stored in the result. By having different, scanner-specific matcher functions, this
- * compatibility check can be made very flexible.
- *
- * TODO: Switch to a more advanced type than String to represent the scanner configuration.
- */
-typealias ScannerConfigMatcher = (String) -> Boolean
-
 /**
  * A data class defining selection criteria for scanners.
  *
@@ -69,17 +57,12 @@ data class ScannerCriteria(
     val maxVersion: Semver,
 
     /**
-     * A function to check whether the configuration of a scanner is compatible with this [ScannerCriteria].
+     * Criterion to match the [configuration][ScannerDetails.configuration] of the scanner. If `null`, all
+     * configurations are matched.
      */
-    val configMatcher: ScannerConfigMatcher
+    val configuration: String?
 ) {
     companion object {
-        /**
-         * A matcher for scanner configurations that accepts all configurations passed in. This function can be
-         * used if the concrete configuration of a scanner is irrelevant.
-         */
-        val ALL_CONFIG_MATCHER: ScannerConfigMatcher = { true }
-
         /**
          * The name of the property defining the regular expression for the scanner name as part of [ScannerCriteria].
          * The [scanner details][ScannerDetails] of the corresponding scanner must match the criteria.
@@ -99,10 +82,10 @@ data class ScannerCriteria(
         const val PROP_CRITERIA_MAX_VERSION = "maxVersion"
 
         /**
-         * A matcher for scanner configurations that accepts only exact matches of the [originalConfig]. This
-         * function can be used by scanners that are extremely sensitive about their configuration.
+         * The name of the property defining the configuration of the scanner as part of [ScannerCriteria]. The
+         * [scanner details][ScannerDetails] of the corresponding scanner must match the criteria.
          */
-        fun exactConfigMatcher(originalConfig: String): ScannerConfigMatcher = { config -> originalConfig == config }
+        const val PROP_CRITERIA_CONFIGURATION = "configuration"
 
         /**
          * Generate a [ScannerCriteria] instance that is compatible with the given [details] and versions that differ
@@ -122,7 +105,7 @@ data class ScannerCriteria(
                 regScannerName = details.name,
                 minVersion = minVersion,
                 maxVersion = maxVersion,
-                configMatcher = exactConfigMatcher(details.configuration)
+                configuration = details.configuration
             )
         }
 
@@ -138,8 +121,9 @@ data class ScannerCriteria(
             val minVersion = parseVersion(options[PROP_CRITERIA_MIN_VERSION]) ?: scannerVersion
             val maxVersion = parseVersion(options[PROP_CRITERIA_MAX_VERSION]) ?: minVersion.nextMinor()
             val name = options[PROP_CRITERIA_NAME] ?: details.name
+            val configuration = options[PROP_CRITERIA_CONFIGURATION] ?: details.configuration
 
-            return ScannerCriteria(name, minVersion, maxVersion, exactConfigMatcher(details.configuration))
+            return ScannerCriteria(name, minVersion, maxVersion, configuration)
         }
     }
 
@@ -160,7 +144,8 @@ data class ScannerCriteria(
         if (!nameRegex.matches(details.name)) return false
 
         val version = Semver(details.version)
-        return minVersion <= version && version < maxVersion && configMatcher(details.configuration)
+        return minVersion <= version && version < maxVersion &&
+            (configuration == null || configuration == details.configuration)
     }
 }
 

scanner/src/test/kotlin/ScannerCriteriaTest.kt

@@ -27,22 +27,6 @@ import org.ossreviewtoolkit.model.ScannerDetails
 import org.semver4j.Semver
 
 class ScannerCriteriaTest : WordSpec({
-    "ScannerCriteria" should {
-        "provide a config matcher that accepts every configuration" {
-            ScannerCriteria.ALL_CONFIG_MATCHER("") shouldBe true
-            ScannerCriteria.ALL_CONFIG_MATCHER("foo") shouldBe true
-            ScannerCriteria.ALL_CONFIG_MATCHER("Supercalifragilisticexpialidocious") shouldBe true
-        }
-
-        "provide a config matcher that accepts only exact configuration matches" {
-            val orgConfig = "--info --copyright --licenses"
-            val matcher = ScannerCriteria.exactConfigMatcher(orgConfig)
-
-            matcher(orgConfig) shouldBe true
-            matcher("$orgConfig --more") shouldBe false
-        }
-    }
-
     "ScannerCriteria.forDetails()" should {
         "create criteria that only match the passed details by default" {
             val criteria = ScannerCriteria.forDetails(testDetails)
@@ -73,20 +57,23 @@ class ScannerCriteriaTest : WordSpec({
             criteria.regScannerName shouldBe SCANNER_NAME
             criteria.minVersion.version shouldBe SCANNER_VERSION
             criteria.maxVersion shouldBe Semver(SCANNER_VERSION).nextMinor()
+            criteria.configuration shouldBe SCANNER_CONFIGURATION
         }
 
         "obtain values from the configuration" {
             val options = mapOf(
                 ScannerCriteria.PROP_CRITERIA_NAME to "foo",
                 ScannerCriteria.PROP_CRITERIA_MIN_VERSION to "1.2.3",
-                ScannerCriteria.PROP_CRITERIA_MAX_VERSION to "4.5.6"
+                ScannerCriteria.PROP_CRITERIA_MAX_VERSION to "4.5.6",
+                ScannerCriteria.PROP_CRITERIA_CONFIGURATION to "config"
             )
 
             val criteria = ScannerCriteria.create(testDetails, options)
 
             criteria.regScannerName shouldBe "foo"
             criteria.minVersion.version shouldBe "1.2.3"
             criteria.maxVersion.version shouldBe "4.5.6"
+            criteria.configuration shouldBe "config"
         }
 
         "parse versions in a lenient way" {
@@ -100,13 +87,6 @@ class ScannerCriteriaTest : WordSpec({
             criteria.minVersion.version shouldBe "1.0.0"
             criteria.maxVersion.version shouldBe "3.7.0"
         }
-
-        "use an exact configuration matcher" {
-            val criteria = ScannerCriteria.create(testDetails)
-
-            criteria.configMatcher(testDetails.configuration) shouldBe true
-            criteria.configMatcher(testDetails.configuration + "_other") shouldBe false
-        }
     }
 
     "ScannerCriteria.matches()" should {
@@ -144,26 +124,31 @@ class ScannerCriteriaTest : WordSpec({
             criteria.matches(testDetails) shouldBe false
         }
 
-        "detect a difference reported by the config matcher" {
-            val criteria = matchingCriteria.copy(
-                configMatcher = ScannerCriteria.exactConfigMatcher(testDetails.configuration + "_other")
-            )
+        "detect a scanner configuration that does not match" {
+            val criteria = matchingCriteria.copy(configuration = "${testDetails.configuration}_other")
 
             criteria.matches(testDetails) shouldBe false
         }
+
+        "ignore the scanner configuration if it is null" {
+            val criteria = matchingCriteria.copy(configuration = null)
+
+            criteria.matches(testDetails) shouldBe true
+        }
     }
 })
 
 private const val SCANNER_NAME = "ScannerCriteriaTest"
 private const val SCANNER_VERSION = "3.2.1-rc2"
+private const val SCANNER_CONFIGURATION = "--command-line-option"
 
 /** Test details to match against. */
-private val testDetails = ScannerDetails(SCANNER_NAME, SCANNER_VERSION, "--command-line-option")
+private val testDetails = ScannerDetails(SCANNER_NAME, SCANNER_VERSION, SCANNER_CONFIGURATION)
 
 /** A test instance which should accept the test details. */
 private val matchingCriteria = ScannerCriteria(
     regScannerName = testDetails.name,
     minVersion = Semver(testDetails.version),
     maxVersion = Semver(testDetails.version).nextPatch(),
-    configMatcher = ScannerCriteria.exactConfigMatcher(testDetails.configuration)
+    configuration = testDetails.configuration
 )

scanner/src/test/kotlin/storages/ClearlyDefinedStorageTest.kt

@@ -106,11 +106,7 @@ private val TEST_PACKAGE =
     )
 
 /** The scanner details used by tests. */
-private val SCANNER_CRITERIA =
-    ScannerCriteria(
-        "aScanner", Semver("1.0.0"), Semver("2.0.0"),
-        ScannerCriteria.exactConfigMatcher("aConfig")
-    )
+private val SCANNER_CRITERIA = ScannerCriteria("aScanner", Semver("1.0.0"), Semver("2.0.0"), "aConfig")
 
 /** The template for a ClearlyDefined definitions request. */
 private val DEFINITIONS_TEMPLATE = readDefinitionsTemplate()