KON-312 Add Konsist Test Which Check If All Snippets Are Used

lib/src/konsistTest/kotlin/com/lemonappdev/konsist/core/SnippetKonsistTest.kt

@@ -0,0 +1,45 @@
+package com.lemonappdev.konsist.core
+
+import com.lemonappdev.konsist.api.Konsist
+import com.lemonappdev.konsist.core.filesystem.PathProvider
+import com.lemonappdev.konsist.core.util.KotlinFileParser
+import org.amshove.kluent.shouldBeEqualTo
+import org.junit.jupiter.api.Test
+import java.io.File
+
+class SnippetKonsistTest {
+    @Test
+    fun `every snippet is used in tests`() {
+        // given
+        val snippets = File("$rootProjectPath/lib/src/integrationTest/kotlin/com/lemonappdev/konsist/core/")
+            .walk()
+            .filter { it.isKotlinSnippetFile }
+            .map { it.name.removeSuffix(".kttxt") }
+            .toSet()
+
+        val r1 = Regex("""getSnippetFile\("(.+)"\)""")
+        val r2 = Regex("""arguments\("([^"]+)"""")
+        val withGetSnippetMethod = snippetNamesFromFiles(r1, "getSnippetFile(\"", "\")")
+        val withArgument = snippetNamesFromFiles(r2, "arguments(\"", "\"")
+        val snippetNamesUsedInTests = (withGetSnippetMethod + withArgument).toSet()
+
+        // then
+        val actual = snippets - snippetNamesUsedInTests
+        actual shouldBeEqualTo emptySet()
+    }
+
+    private fun snippetNamesFromFiles(regex: Regex, prefix: String, suffix: String) = snippetPackageScope
+        .files()
+        .map { it.text }
+        .flatMap { regex.findAll(it) }
+        .map { it.value }
+        .map { it.removePrefix(prefix) }
+        .map { it.removeSuffix(suffix) }
+
+    companion object {
+        private val snippetPackageScope = Konsist.scopeFromTest(sourceSetName = "integrationTest")
+        private val pathProvider: PathProvider by lazy { PathProvider.getInstance() }
+        private val rootProjectPath = pathProvider.rootProjectPath
+        private val File.isKotlinSnippetFile get() = isFile && name.endsWith(KotlinFileParser.KOTLIN_SNIPPET_FILE_EXTENSION)
+    }
+}

lib/src/main/kotlin/com/lemonappdev/konsist/core/filesystem/PathProvider.kt

@@ -36,6 +36,6 @@ class PathProvider(
     companion object {
         private val pathVerifier = PathVerifier()
 
-        internal fun getInstance() = PathProvider(KoFileFactory(), ProjectRootDirProviderFactory(pathVerifier))
+        fun getInstance() = PathProvider(KoFileFactory(), ProjectRootDirProviderFactory(pathVerifier))
     }
 }