Don't allow invalid Source Locations (#7030)

* Improve tests

* Don't add invalid values on SourceLocation

* Don't hide problems with coerce

* Fix wording in assertion messages

---------

Co-authored-by: Matthew Haughton <3flex@users.noreply.github.com>

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

@@ -60,7 +60,7 @@ class Location(
 
         private fun lineAndColumn(element: PsiElement, range: TextRange): PsiDiagnosticUtils.LineAndColumn {
             return getLineAndColumnInPsiFile(element.containingFile, range)
-                ?: PsiDiagnosticUtils.LineAndColumn(-1, -1, null)
+                ?: PsiDiagnosticUtils.LineAndColumn(1, 1, null)
         }
     }
 }
@@ -70,6 +70,11 @@ class Location(
  */
 @Poko
 class SourceLocation(val line: Int, val column: Int) {
+    init {
+        require(line > 0) { "The source location line must be greater than 0" }
+        require(column > 0) { "The source location column must be greater than 0" }
+    }
+
     override fun toString(): String = "$line:$column"
 }
 

detekt-core/src/test/kotlin/io/gitlab/arturbosch/detekt/core/suppressors/Builders.kt

@@ -21,7 +21,7 @@ private fun buildEmptyEntity(): Entity = Entity(
     name = "",
     signature = "",
     location = Location(
-        source = SourceLocation(0, 0),
+        source = SourceLocation(1, 1),
         text = TextLocation(0, 0),
         filePath = FilePath.fromAbsolute(Path("/"))
     ),

detekt-psi-utils/src/main/kotlin/io/github/detekt/psi/KtFiles.kt

@@ -83,10 +83,14 @@ fun PsiFile.toFilePath(): FilePath {
 
 // #3317 If any rule mutates the PsiElement, searching the original PsiElement may throw an exception.
 fun getLineAndColumnInPsiFile(file: PsiFile, range: TextRange): PsiDiagnosticUtils.LineAndColumn? {
-    return runCatching {
-        @Suppress("ForbiddenMethodCall")
-        DiagnosticUtils.getLineAndColumnInPsiFile(file, range)
-    }.getOrNull()
+    return if (file.textLength == 0) {
+        null
+    } else {
+        runCatching {
+            @Suppress("ForbiddenMethodCall")
+            DiagnosticUtils.getLineAndColumnInPsiFile(file, range)
+        }.getOrNull()
+    }
 }
 
 private fun buildPlatformSpecificSuffixes(platforms: List<String>): List<String> =

detekt-rules-empty/src/test/kotlin/io/gitlab/arturbosch/detekt/rules/empty/EmptyKotlinFileSpec.kt

@@ -9,29 +9,31 @@ import org.junit.jupiter.api.Test
 class EmptyKotlinFileSpec {
     private val subject = EmptyKotlinFile(Config.empty)
 
-    private val codeWithPackageStatement = """
-            package my.packagee
-    """.trimIndent()
-
-    private val codeWithFunction = """
-            package my.packagee
-            
-            fun myFunction() {}
-    """.trimIndent()
-
     @Test
     fun `reports empty if file is blank`() {
         val code = ""
-        assertThat(subject.lint(code)).hasSize(1)
+        assertThat(subject.lint(code))
+            .singleElement()
+            .hasSourceLocation(1, 1)
     }
 
     @Test
     fun `does report file with package statement`() {
-        assertThat(subject.compileAndLint(codeWithPackageStatement)).hasSize(1)
+        val codeWithPackageStatement = """
+            package my.packagee
+        """.trimIndent()
+        assertThat(subject.compileAndLint(codeWithPackageStatement))
+            .singleElement()
+            .hasSourceLocation(1, 1)
     }
 
     @Test
     fun `does not report file with code`() {
-        assertThat(subject.compileAndLint(codeWithFunction)).hasSize(0)
+        val code = """
+            package my.packagee
+
+            fun myFunction() {}
+        """.trimIndent()
+        assertThat(subject.compileAndLint(code)).isEmpty()
     }
 }