NamedArguments: fix false positive with varargs (#3294)

detekt · Dec 18, 2020 · 37f0a1d · 37f0a1d
1 parent 3409f39
commit 37f0a1d
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Showing 2 changed files with 40 additions and 9 deletions.
diff --git a/...complexity/src/main/kotlin/io/gitlab/arturbosch/detekt/rules/complexity/NamedArguments.kt b/...complexity/src/main/kotlin/io/gitlab/arturbosch/detekt/rules/complexity/NamedArguments.kt
@@ -9,6 +9,7 @@ import io.gitlab.arturbosch.detekt.api.Severity
 import io.gitlab.arturbosch.detekt.api.ThresholdRule
 import org.jetbrains.kotlin.psi.KtCallExpression
 import org.jetbrains.kotlin.resolve.BindingContext
+import org.jetbrains.kotlin.resolve.calls.callUtil.getParameterForArgument
 import org.jetbrains.kotlin.resolve.calls.callUtil.getResolvedCall
 
 /**
@@ -43,16 +44,22 @@ class NamedArguments(
     override fun visitCallExpression(expression: KtCallExpression) {
         if (bindingContext == BindingContext.EMPTY) return
         val valueArguments = expression.valueArguments
-        if (valueArguments.size > threshold &&
-            valueArguments.any { !it.isNamed() } &&
-            expression.getResolvedCall(bindingContext)?.candidateDescriptor?.hasStableParameterNames() == true
-        ) {
+        if (valueArguments.size > threshold && expression.canNameArguments()) {
             report(CodeSmell(issue, Entity.from(expression), issue.description))
         } else {
             super.visitCallExpression(expression)
         }
     }
 
+    private fun KtCallExpression.canNameArguments(): Boolean {
+        val resolvedCall = getResolvedCall(bindingContext) ?: return false
+        if (!resolvedCall.candidateDescriptor.hasStableParameterNames()) return false
+        val unnamedArguments = valueArguments.filter { !it.isNamed() }
+        return unnamedArguments.isNotEmpty() && unnamedArguments.all {
+            resolvedCall.getParameterForArgument(it)?.varargElementType == null || it.getSpreadElement() != null
+        }
+    }
+
     companion object {
         const val DEFAULT_FUNCTION_THRESHOLD = 3
     }

diff --git a/...lexity/src/test/kotlin/io/gitlab/arturbosch/detekt/rules/complexity/NamedArgumentsSpec.kt b/...lexity/src/test/kotlin/io/gitlab/arturbosch/detekt/rules/complexity/NamedArgumentsSpec.kt
@@ -117,14 +117,38 @@ class NamedArgumentsSpec : Spek({
 
         it("java method invocation should not be flagged") {
             val code = """
-            import java.time.LocalDateTime
-            
-            fun test() {
-                LocalDateTime.of(2020, 3, 13, 14, 0, 0)
-            }
+                import java.time.LocalDateTime
+                
+                fun test() {
+                    LocalDateTime.of(2020, 3, 13, 14, 0, 0)
+                }
+            """
+            val findings = namedArguments.compileAndLintWithContext(env, code)
+            assertThat(findings).hasSize(0)
+        }
+
+        it("invocation with varargs should not be flagged") {
+            val code = """
+                fun foo(vararg i: Int) {}
+                fun bar(a: Int, b: Int, c: Int, vararg s: String) {}
+                fun test() {
+                    foo(1, 2, 3, 4, 5)
+                    bar(1, 2, 3, "a")
+                }
             """
             val findings = namedArguments.compileAndLintWithContext(env, code)
             assertThat(findings).hasSize(0)
         }
+
+        it("invocation with spread operator should be flagged") {
+            val code = """
+                fun bar(a: Int, b: Int, c: Int, vararg s: String) {}
+                fun test() {
+                    bar(1, 2, 3, *arrayOf("a"))
+                }
+            """
+            val findings = namedArguments.compileAndLintWithContext(env, code)
+            assertThat(findings).hasSize(1)
+        }
     }
 })