Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Jump to bottom

Fix false negative SafeCast with no braces #5479

Merged
merged 1 commit into from Oct 26, 2022
Merged

Fix false negative SafeCast with no braces #5479

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Jump to
Jump to file
Failed to load files.
Diff view
Diff view
18 changes: 13 additions & 5 deletions detekt-rules-style/src/main/kotlin/io/gitlab/arturbosch/detekt/rules/style/SafeCast.kt
View file
Open in desktop
Expand Up @@ -8,7 +8,9 @@ import io.gitlab.arturbosch.detekt.api.Issue
import io.gitlab.arturbosch.detekt.api.Rule
import io.gitlab.arturbosch.detekt.api.Severity
import io.gitlab.arturbosch.detekt.api.internal.ActiveByDefault
import io.gitlab.arturbosch.detekt.rules.safeAs
import org.jetbrains.kotlin.KtNodeTypes
import org.jetbrains.kotlin.psi.KtBlockExpression
import org.jetbrains.kotlin.psi.KtConstantExpression
import org.jetbrains.kotlin.psi.KtExpression
import org.jetbrains.kotlin.psi.KtIfExpression
Expand Down Expand Up @@ -61,13 +63,19 @@ class SafeCast(config: Config = Config.empty) : Rule(config) {
}
}

private fun isIfElseNull(thenClause: KtExpression?, elseClause: KtExpression?, identifier: String): Boolean {
val hasIdentifier = thenClause?.children?.firstOrNull()?.text == identifier
val elseStatement = elseClause?.children?.firstOrNull()
val hasNull = elseStatement is KtConstantExpression && elseStatement.node.elementType == KtNodeTypes.NULL
return hasIdentifier && hasNull
private fun isIfElseNull(thenClause: KtExpression?, elseClause: KtExpression?, identifier: String): Boolean =
thenClause.isIdentifier(identifier) && elseClause.isNullConstant()

private fun KtExpression?.isIdentifier(identifier: String): Boolean = singleExpression()?.text == identifier

private fun KtExpression?.isNullConstant(): Boolean {
val singleExpression = singleExpression() ?: return false
return singleExpression is KtConstantExpression && singleExpression.node.elementType == KtNodeTypes.NULL
}

private fun KtExpression?.singleExpression(): KtExpression? =
if (this is KtBlockExpression) children.singleOrNull()?.safeAs() else this

private fun addReport(expression: KtIfExpression) {
report(CodeSmell(issue, Entity.from(expression), "This cast should be replaced with a safe cast: as?"))
}
Expand Down
20 changes: 20 additions & 0 deletions detekt-rules-style/src/test/kotlin/io/gitlab/arturbosch/detekt/rules/style/SafeCastSpec.kt
View file
Open in desktop
Expand Up @@ -35,6 +35,26 @@ class SafeCastSpec {
assertThat(subject.compileAndLint(code)).hasSize(1)
}

@Test
fun `reports negated expression with no braces`() {
val code = """
fun test(element: Int) {
val cast = if (element !is Number) null else element
}
""".trimIndent()
assertThat(subject.compileAndLint(code)).hasSize(1)
}

@Test
fun `reports expression with no braces`() {
val code = """
fun test(element: Int) {
val cast = if (element is Number) element else null
}
""".trimIndent()
assertThat(subject.compileAndLint(code)).hasSize(1)
}

@Test
fun `does not report wrong condition`() {
val code = """
Expand Down