Merge pull request #246 from yokotaso/Issue-238

Issues#238 Rule About package name

ktlint-ruleset-standard/src/main/kotlin/com/github/shyiko/ktlint/ruleset/standard/PackageNameRule.kt

@@ -0,0 +1,49 @@
+package com.github.shyiko.ktlint.ruleset.standard
+
+import com.github.shyiko.ktlint.core.KtLint
+import com.github.shyiko.ktlint.core.Rule
+import org.jetbrains.kotlin.com.intellij.lang.ASTNode
+import org.jetbrains.kotlin.psi.KtPackageDirective
+import org.jetbrains.kotlin.psi.stubs.elements.KtStubElementTypes
+import java.io.File
+
+/**
+ * @see [kotlin style guide](https://kotlinlang.org/docs/reference/coding-conventions.html#naming-rules)
+ * @see [android style guide](https://android.github.io/kotlin-guides/style.html#package-names)
+ * @author yokotaso <yokotaso.t@gmail.com>
+ */
+class PackageNameRule : Rule("package-name-rule") {
+    private var filePath: String? = null
+
+    override fun visit(
+        node: ASTNode,
+        autoCorrect: Boolean,
+        emit: (offset: Int, errorMessage: String, canBeAutoCorrected: Boolean) -> Unit
+    ) {
+        if (node.elementType == KtStubElementTypes.FILE) {
+            filePath = node.getUserData(KtLint.FILE_PATH_USER_DATA_KEY)
+        }
+
+        if (node.elementType == KtStubElementTypes.PACKAGE_DIRECTIVE) {
+            val qualifiedName = (node.psi as KtPackageDirective).qualifiedName
+            if (packageNameNotContainsDirectoryPath(qualifiedName)) {
+                emit(node.startOffset, "package name should match directory name.", false)
+            }
+
+            if (qualifiedName.contains('_', false)) {
+                emit(node.startOffset, "package names should be not contain underscore.", false)
+            }
+        }
+    }
+
+    private fun packageNameNotContainsDirectoryPath(qualifiedName: String): Boolean {
+        var filePathFromQualifiedName = qualifiedName.replace('.', File.separatorChar, false)
+        // Skip package name is empty
+        if (filePathFromQualifiedName.isEmpty()) {
+            return false
+        }
+
+        val actualFilePath = filePath.orEmpty()
+        return actualFilePath.contains(filePathFromQualifiedName).not()
+    }
+}

ktlint-ruleset-standard/src/main/kotlin/com/github/shyiko/ktlint/ruleset/standard/StandardRuleSetProvider.kt

@@ -10,6 +10,7 @@ class StandardRuleSetProvider : RuleSetProvider {
         CommentSpacingRule(),
         FilenameRule(),
         FinalNewlineRule(),
+        PackageNameRule(),
         UseWhiteSpaceInsteadOfTabRule(),
         IfElseMultiLineBlockWithCurlBraceRule(),
         // disabled until it's clear how to reconcile difference in Intellij & Android Studio import layout

ktlint-ruleset-standard/src/test/kotlin/com/github/shyiko/ktlint/ruleset/standard/PackageNameRuleTest.kt

@@ -0,0 +1,59 @@
+package com.github.shyiko.ktlint.ruleset.standard
+
+import com.github.shyiko.ktlint.core.LintError
+import com.github.shyiko.ktlint.test.lint
+import org.assertj.core.api.Assertions.assertThat
+import org.testng.annotations.Test
+import java.net.URI
+import java.nio.file.Paths
+
+/**
+ * @author yokotaso <yokotaso.t@gmail.com>
+ */
+class PackageNameRuleTest {
+
+    @Test
+    fun testPackageName_Success() {
+        lintSuccess("package hoge.fuga", "/hoge/fuga/A.kt")
+        lintSuccess("package hoge.fuga\nclass B{}", "/hoge/fuga/B.kt")
+        lintSuccess("package hoge.fuga\nclass C{}", "/var/tmp/hoge/fuga/C.kt")
+        lintSuccess("package hoge.fuga\nclass B{}\nclass C{}", "/var/tmp/hoge/fuga/Mix.kt")
+        lintSuccess("package hoge.fuga\nfun main() {}", "/var/tmp/hoge/fuga/main.kt")
+        lintSuccess("class A{}", "/var/tmp/hoge/fuga/A.kt")
+    }
+
+    @Test
+    fun testPackageName_Failed() {
+        lintFailed(
+            "package hoge.fuga",
+            "/hoge/moge/A.kt",
+            listOf(LintError(1, 1, "package-name-rule", "package name should match directory name.")
+        ))
+    }
+
+    @Test
+    fun testPackageName_UnderScoreContains() {
+        lintFailed(
+            "package hoge.moge.hoge_moge",
+            "/hoge/moge/hoge_moge/A.kt",
+            listOf(LintError(1, 1, "package-name-rule", "package names should be not contain underscore.")
+            ))
+    }
+
+    @Test
+    fun testPackageName_UpperCaseContains() {
+        lintSuccess(
+            "package hoge.moge.hogeMoge",
+            "/hoge/moge/hogeMoge/A.kt")
+    }
+
+    private fun fileName(fileName: String) = mapOf("file_path" to Paths.get(URI.create("file:///$fileName")).toString())
+
+    private fun lintSuccess(ktScript: String, fileName: String) {
+        assertThat(PackageNameRule().lint(ktScript, fileName(fileName))).isEmpty()
+    }
+
+    private fun lintFailed(ktScript: String, fileName: String, lintErrors: List<LintError>) {
+        assertThat(PackageNameRule().lint(ktScript, fileName(fileName))).isEqualTo(lintErrors)
+    }
+}